Home

Firmware User Manual

Contents

1. 3 14 Channel Allocation and Signal Selection The receiver automatically allocates satellites to tracking channels up to the limit of the number of channels It is possible to override this automatic channel allocation by forcing a satellite to a given channel by using the setChannelAllocation command Also a subset of satellites or a whole constellation can be disabled with the setSatelliteTracking command For each satellite the receiver tries to track all signal types enabled with the setSignalTracking command For example if that command enables the GPSLICA GPSL2PY and GLOLICA signals GPS satellites will be tracked in dual frequency mode GPSLICA and GPSL2PY and GLONASS satellites will be tracked in single frequency mode GLOLICA only It is a good practice to only enable those signal types that are needed for your application to avoid wasting tracking channels 3 2 Generation of Measurements For each tracked GNSS signal the receiver generates a measurement set mainly consisting of the following observables a pseudorange in meters e a carrier phase in cycles a Doppler in Hertz e a carrier to noise ratio in dB Hz All data in a measurement set and all measurement sets are taken at the same time which is referred to as the measurement epoch All the measurement sets taken at a given measurement epoch are output in a MeasEpoch SBF block Several commands affect the way the receiver produces and outputs m
2. GPSUtc optional needed only if the header should contain UTC related data GLO Navigation G GLONav GPSUtc or GALUtc this is mandatory without at least one GPSUtc or GALUtc block in the file sb 2rin is unable to enerate a GLONASS navigation file Galileo Navigation L EN av GALIon optional GALUtc optional SBAS Navigation H GEONav SBAS Broadcast B GEORawL1 Meteo file M ASCIIIn 2 Use RxControl or any suitable communication program to log the raw bytes coming from the receiver Make sure that no character translation is applied by your logging program Let s call the log file LOG SBF It is possible that LOG S BF does not only contain SBF blocks since the receiver may output other data in between two SBF blocks replies to user commands NMEA Firmware User Manual for SSRC4 2 5 2 56 Septentrio APPENDIX B SBF2RIN UTILITY atellite navigation sentences This is not a problem the SBF header allows identifying the SBF blocks in the raw stream from the receiver 3 Use sbf2rin to generate a RINEX file from the log file LOG SBF sbf2rin f LOG SBF CR Note that the size of the SBF file must not exceed 2GBytes By default sb 2rin generates a RINEX v2 11 observation file Invoking sb 2rin without argument prints the list of options and their usage sbf2rin f input file o output file i interval b st
3. Septentrio atellite navigation Firmware User Manual Applicable to SSRC4 2 5 2 Firmware User Manual for SSRCA 2 5 2 Septentrio atellite navigation Firmware User Manual Revision 0 July 02 2013 Applicable to SSRC4 2 5 2 Copyright 2000 2013 Septentrio nv sa All rights reserved Septentrio Satellite Navigation Greenhill Campus Interleuvenlaan 15G B 3001 Leuven Belgium http www septentrio com support septentrio com Phone 32 16 300 800 Fax 32 16 221 640 Firmware User Manual for SSRCA 2 5 2 Septentrio LIST OF CONTENTS atellite navigation List of Contents LIST OF ACRONYMS 5 1 QUICK START 7 1 41 Quick Start Equipment eese ext I eR RE eR Rr ges 7 1 2 Omek Start Procedure oco Rd e SLE M etr lata das SEE Ra DE SORIA 7 2 How TO 9 2 1 Conmect to the Receiver eee e l e e REIR d RR RR RITE elo 10 2 1 1 Via COM Ports eR Gd isse RUE RR EET SAID 10 2 1 2 Via USB icc Roe e du Ed ed 10 21 3 Vaa TCP IP Port cO e 10 214 Viza Web Browser ior lane sta Is aaah eee aaa 11 ZES MIRLETPu Lii edane e a i cadens Ee erts needs ELE ed 12 2 1 0 Connection Descriptors sspe re eb eik Ie DI EEEE Qu 13 2 2 Understand the Output of the Receiver 00 cece cece cece cere m 14 2 2 1 Proprietary Binary Output SBF cee cece cee ence ee 14 2227 INMBA cote RD LR eels aE D as he tis 14 2 2 3 RT CM and CMR ices cc ceccedicneeehiite cee ceeded Seen ee hte dep
4. On Geodesy Vol 2 no 5 1968 Firmware User Manual for SSRCA 2 5 2 47 Septentrio 3 OPERATION DETAILS atellite navigation minimal detectable bias False Alarm Missed Detection Figure 3 4 Statistical test outcomes Samples corresponding to the four test outcomes are represented in Figure 3 4 samples A and B are from the unbiased measurement distribution while samples C and D are from a biased measurement distribution corresponding to an outlier Since sample A is larger than the test threshold it will be incorrectly flagged as an outlier false alarm Sample C is not detected as an outlier although it is part of the biased distribution missed detection The acceptable probability of false alarm and the probability of missed detection for the application must be determined and provided to the receiver This is the purpose of the setRAIMLevels command 3 5 1 Integrity Algorithm Two kinds of statistical tests are performed the detection step uses an overall model test to evalu ate the integrity of the position solution as a whole and the identification step uses the w test also known as datasnooping to evaluate the integrity of individual measurements Depending on the po sitioning mode the overall model test is computed for range range rate and or phase measurements simultaneously while the w test is computed for each range range rate and or phase measurement individually Both the overall m
5. Please refer to the SBF Reference Guide for a complete definition of SBF The benefit of SBF is compactness This format should be your first choice if you wish to receive detailed information from the receiver The list of supported SBF messages on your particular receiver and firmware version can be found in the Command Line Interface Reference Guide SBF Converter provided in the RxTools package is an intuitive GUI which allows SBF conversion into e g RINEX KML GPX or ASCII 2 2 2 NMEA The receiver can generate a set of approved NMEA sentences which conform to the NMEA Stan dard The benefit of the NMEA format is that it is standardized Many electronic devices and software packages support NMEA The drawback of NMEA is a relatively low level of detail Ap pendix A provides a short overview of selected NMEA sentences NMEA output can be invoked with the setNMEAOutput command RxControl Communication gt Output Settings gt NMEA Output gt NMEA Output Intervals NMEA 0183 Standard for Interfacing Marine Electronic Devices Version 2 30 National Marine Electronics Associa tion 1998 Firmware User Manual for SSRC4 2 5 2 14 Septentrio acm atellite navigation Web Interface Configuration Communication gt Output Settings gt NMEA Output gt NMEA Output Intervals 2 2 3 RTCM and CMR If this feature is enabled in your receiver the receiver can operate as DGPS and or RTK base station and output the co
6. RAIM may remove too many wrongly identified outliers see also section 3 5 This behaviour will be more visible if the ARP coordinates are not accurately set A measurement that has been identified as outlier in the base station will not be included in the RTCM and CMR messages For best performance it is recommended to use non default values for the RAIM probability of false alarm and model reliability The following settings are recommended SetRAIMLevels on 2 2 3 CR RxControl Navigation gt Receiver Operation gt Position gt Integrity Web Interface Configuration Navigation gt Receiver Operation gt Position gt Integrity 4 For RTCM 3 x the antenna information in message types 1007 1008 and 1033 can be specified using the setAntennaOffset command with the serial number as sixth argument and the antenna type called antenna descriptor in RTCM as fifth argument see also section 3 4 3 6 For instance setAntennaOffset Main AT2775 54SW 5684 CR RxControl Navigation gt Receiver Setup gt Antennas Web Interface Configuration Navigation gt Receiver Setup gt Antennas 5 Use the commands setRTCMv2Interval setRTCMv2IntervalObs set RTCMv3In terval or setCMRv2Interval to specify the message interval The default interval is given in the description of these commands in the Command Line Interface Reference Guide For instance to change the default interval at which RTCM 2 x message type 3 is genera
7. RINEX RTCA RTCM RTK A Posteriori Multipath Estimation Antenna Reference Point American Standard Code for Information Interchange Compact Measurement Record Central Processing Unit Carriage Return Differential Global Positioning System Dynamic Host Configuration Protocol Dilution of Precision European Geostationary Navigation Overlay System EGNOS System Test Bed Field Programmable Gate Array Global Orbiting Navigation Satellite System Russian alternative for GPS Global Navigation Satellite System Global Positioning System GPS eXchange Graphical User Interface Horizontal External Reliability Level Horizontal Protection Level International GNSS Service Inertial Measurement Unit Inertial Navigation System Keyhole Markup Language Least squares Ambiguity Decorrelation Adjustment Light Emitting Diode Minimal Detectable Bias Minimum Operational Performance Standards Message Type National Marine Electronics Association On the Fly Phase Center Precise Point Positioning Pulse Per Second Position Velocity Time Receiver Autonomous Integrity Monitoring Receiver Independent Exchange Format Radio Technical Commission for Aeronautics Radio Technical Commission for Maritime Services Real Time Kinematic Firmware User Manual for SSRC4 2 5 2 5 Septentrio fide OR ACRONTMS atellite navigation RTS SBAS SBF SD SDHC SIS SNMP TOW USB UTC VERL VPL WAAS WN XERL Request to Send Space Based
8. SBF CR RxControl Communication 7 Input Output Selection Web Interface Configuration Communication gt Input Output Selection Firmware User Manual for SSRCA 2 5 2 16 Septentrio i Howe atellite navigation 2 4 Save the Configuration in Non Volatile Memory The receiver configuration includes all the user selectable parameters such as the elevation mask the PVT mode the COM port settings By default the receiver starts up in its factory default configuration The factory defaults for each of the receiver parameters are underlined for each argument of each command in the Command Line Interface Reference Guide At any time it is possible to save the current receiver configuration into non volatile memory in order to force the receiver to always start up in that configuration To do so the following command should be entered exeCopyConfigFile Current Boot CR RxControl File gt Copy Configuration Web Interface Receiver Administration gt Copy Configuration To revert to the default setting where the receiver starts in the default configuration you should use exeCopyConfigFile RxDefault Boot CR Firmware User Manual for SSRCA 2 5 2 17 Septentrio T atellite navigation 2 5 Configure the Receiver in DGPS RTK Base Mode The receiver can generate and output DGPS corrections or RTK data in the RTCM and CMR formats The list of RTCM and CMR messages available on your particular receiver and
9. sn3000926 tcpip Download Internal Files 3 Help Name Size Locked EE 4 DSK1 15 GB 1 9 GB aj02185p 11_ 12 4MB no E aj021850 11_ 13 4MB no aj02185q 11_ 12 8 MB no aj02185r11_ 13 3 MB no 3j021855 11 117 MB no aj02185t 11 117 MB no aj02185u 11 12 1 MB no 3j02185411 12 8 MB no aj02185w 11 12 7 MB no Download to C sleewae all 4i Default File aj021850 11 We ooo 53 Total 0 of 2 file s 0 _ Remove Internal File after download Refresh File List Cancel Close Figure 2 2 Download Internal Files from RxControl Through FTP see section 2 1 5 Using the web interface The web interface allows you to view the contents of the memory card and to delete files select the Logging tab and then Remove Internal File For file download you will need to use FTP access By entering commands manually the command 1stDiskInfo prints the card contents and free space and the command exeRemoveFile can be used to remove a file Firmware User Manual for SSRC4 2 5 2 25 Septentrio i Row nO atellite navigation 2 10 Log RINEX Files on the SD Memory Card The receiver can log the following RINEX file types on its internal SD memory card O observation N GPS nav G GLONASS nav L Galileo nav and H GEO nav RINEX v2 10 v2 11 and 3 02 are supported Internal RINEX logging is typically configured as follows 1 The RINEX file names follow the RINEX naming conve
10. Augmentation System Septentrio Binary Format Secure Digital Secure Digital High Capacity Signal In Space Simple Network Management Protocol Septentrio variant Time Of Week Universal Serial Bus Coordinated Universal Time Vertical External Reliability Level Vertical Protection Level Wide Area Augmentation System Week Number External Reliability Levels Firmware User Manual for SSRC4 2 5 2 Septentrio iudei atellite navigation 1 Quick Start This chapter will help you to get quickly acquainted with your receiver by getting the first position fix 1 1 Quick Start Equipment You will need the following equipment to complete this quick start tutorial An active GPS antenna The standard antenna voltage compatible with the receiver is 5V An antenna cable The USB cable provided with your receiver The power adaptor A host computer which will be needed to operate your receiver and retrieve the data In these quick start instructions you will learn how to use the RxControl program to monitor and control your receiver through the USB cable The CD accompanying the receiver 1 2 Quick Start Procedure Step 1 Place the GNSS antenna horizontally in a place where the sky is not obstructed by buildings or trees Connect the antenna via the antenna cable to the antenna port of the receiver Step 2 Install the RxTools software suite which is to be found on the accompanying CD ROM and which includes various utili
11. Generate a Pulse Per Second Signal The receiver is able to generate an x pulse per second xPPS signal aligned with either GPS Galileo or GLONASS system time or with UTC or with the internal receiver time The interval between pulses can be set to 0 1 0 2 0 5 1 2 5 or 10 seconds By default the PPS is a positive pulse of which the leading edge is synchronous with the second boundaries of the time system selected with the set TimingSystem command GPS or Galileo Check the Hardware Manual for the voltage and the duration of the pulse The command setPPSParameters can be used to synchronize the PPS with UTC GLONASS or the internal time or to alter the PPS interval and polarity For instance to synchronize the PPS with UTC and have one pulse every ten seconds use setPPSParameters secl10 UTC CR RxControl Navigation 7 Receiver Operation 7 Timing Web Interface Configuration Navigation gt Receiver Operation gt Timing By default the PPS pulse is calibrated so that it arrives at the right time 10ns at the PPS output port of the receiver when there is no antenna delays no cable delays and when the receiver is at a temperature of 20 C In an actual setup the antenna and cable delays will cause the PPS to be offset from its correct position The third argument of the setPPSParameters command can be used to specify the overall antenna and cable delay in order to allow the receiver to compensate for them True PPS
12. OTF ambiguity fixing The RTK positioning engine of the receiver uses the LAMBDA method developed at Delft University department of Geodesy 3 4 3 4 Floating Ambiguities RTK float When data availability is low no L2 data or low number of satellites or when the data are not of sufficient quality high multipath the receiver will not fix the carrier phase ambiguities to their integer value but will keep them floating At the start of the RTK float convergence process the position accuracy is equal to that of code based DGPS Over the course of several minutes the positional gt Teunissen P J G and C C J M Tiberius 1994 Integer least squares estimation of the GPS phase ambiguities Pro ceedings of International Symposium on Kinematic Systems in Geodesy Geomatics and Navigation KIS 94 Banff Canada August 30 September 2 pp 221 231 Firmware User Manual for SSRC4 2 5 2 44 Septentrio 3 OPERATION DETAILS atellite navigation accuracy will converge from several decimeters to several centimeters as the floating ambiguities become more accurate 3 4 3 5 Datum Transformation RTK coordinates are expressed in the same reference frame as the one in which the base station coordinates are expressed For example if the base station coordinates relate to the ETRF frame the RTK coordinates reported in the PVTCartesian and PVTGeodetic SBF blocks will also relate to ETRF However in many cases RTK users must present the
13. Speed Time and Date CMR Message U Ne Message Name Observables Reference Station Coordinates Reference Station Description GLONASS Observables Firmware User Manual for SSRC4 2 5 2 51 Septentrio atellite navigation RTCM 2 x Message Message Name 1 3 9 16 18 19 20 21 22 23 24 31 32 59 Differential GPS Corrections GPS Reference Station Parameters GPS Partial Correction Set GPS Special Message RTK Uncorrected Carrier Phases RTK Uncorrected Pseudoranges RTK Carrier Phase Corrections RTK Hi Accuracy Pseudorange Corrections Extended Reference Station Parameters Antenne Type Definition Record Antenna Reference Point ARP Differential GLONASS Corrections GLONASS Reference Station Parameters Proprietary Message RTCM 3 x Message Message Name 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1015 1016 1017 1021 1022 1023 1033 1037 1038 1039 L1 Only GPS RTK Observables Extended L1 Only GPS RTK Observables L1 amp L2 GPS RTK Observables Extended L1 amp L2 GPS RTK Observables Stationary RTK Reference Station ARP Stationary RTK Reference Station ARP with Antenna Height Antenna Descriptor Antenna Descriptor and Serial Number L1 Only GLONASS RTK Observables Extended L1 Only GLONASS RTK Observables L1 amp L2 GLONASS RTK Observables Extended LI amp L2 GLONASS RTK Observables System Parameters GPS Ionospheric Co
14. Via COM Ports The most straightforward way to communicate with the receiver is to connect one of its COM ports to a COM port of your host computer You can use the provided COM cable for this purpose The operating system you are running on your PC is of no importance you should only be able to run a terminal emulation program like HyperTerminal on Windows or minicom on Linux with full access to the COM port to which the receiver is connected To get connected attach the serial cable power on the receiver and launch your terminal program Make sure that it uses the correct port settings The default settings are Parameter Value baud rate 115200 data bits 8 parity no stop bits 1 flow control none The baud rate can be modified at any time by using the setCOMSettings command RxControl Communication gt COM Port Settings Web Interface Configuration Communication gt COM Port Settings Since the receiver does not echo the incoming characters it is handy to enable the local echo feature of the terminal emulation program in order to see the characters you are typing The easiest way to find out whether your physical and logical connection is established is to press the lt Enter gt key If the connection is correctly established the receiver should reply with a prompt 2 1 2 Via USB The Windows USB driver provided with your receiver emulates two virtual serial ports which can be used as standard COM ports to acc
15. firmware version can be found in the Command Line Interface Reference Guide see the commands setRTCMv2Output setRTCMv3Output and setCMRv2Output 2 5 1 Static Base Station Mode To configure the receiver in static base station mode the following has to be done 1 Connect the receiver to a survey grade antenna at a fixed location 2 For accurate and repetitive absolute positioning you must provide the accurate coordinates of the antenna reference point ARP The ARP usually corresponds to the center of the bottom of the antenna see also section 3 4 3 6 For example assuming the WGS84 position of the ARP is 50 5 N 4 E and its altitude above the WGS84 ellipsoid is 100m use setStaticPosGeodetic Geodetic1 50 5 4 100 CR setPVTMode Static Geodeticl lt CR gt RxControl Navigation gt Positioning Mode gt PVT Mode Web Interface Configuration Navigation gt Positioning Mode gt PVT Mode If you are only interested in accurate determination of the base rover baseline with the absolute position of the rover being of lesser importance accurate positioning of the base station is not required and you may simply let the receiver determine its fixed position autonomously auto base mode by typing setPVTMode Static auto lt CR gt 3 When the PVT engine operates in static mode the PVT residuals are generally larger than in rover mode because only the clock term is estimated Depending on the selected RAIM thresholds
16. the knowledge of the current hour GPS carrier phase measurements behave in the same way we only know the current phase but do not know the total number of wavelengths which make up the range to the satellite the carrier Firmware User Manual for SSRCA 2 5 2 43 Septentrio 3 OPERATION DETAILS atellite navigation phase contains an ambiguity To actually use the carrier phase measurement as a satellite range this ambiguity has to be resolved Summing up pseudorange measurements are low accuracy absolute ranges to GPS satellites while carrier phase measurements are high precision relative ranges to satellites By estimating the am biguity the carrier phase measurements are turned into high accuracy satellite ranges and the low accuracy pseudoranges are not needed for positioning 3 4 3 2 Carrier Phase Positioning To use the high accuracy of the carrier phase measurements error sources such as broadcast ephemeris errors satellite clock errors and atmospheric delay must be eliminated as much as possible This is achieved by performing differential positioning by differencing the phase measurements with those of a receiver at a nearby location The common errors are eliminated and the position can be accu rately estimated with respect to this base station This requires two receivers which are connected by a data link One receiver the base is located at a known location and transmits its position and measurements to another recei
17. 1 Channel Allocation and Signal Selection eee 38 3 2 Generation of Measurements cece cece eee cnet ence e eme eme sees 38 3 2 1 Pilot vs Data Component 00 ccc cece ence eee meme eee 39 3 3 Time Management 0 ccc ccc ccc e e e eme he ehh eene 39 3 3 Pree Rumming Clock ee ope eee er erts 40 3 32 Clock Steering eine seceded Wace bees xn u bese ect dled Nae eren aun 40 3 4 Computation of Position Velocity and Time PVT Solution 0 eee eee 41 3 41 SBAS Positioning 00 cece cece eee e eee eee ees esee 42 3 4 2 DGPS Positioning Single and Multi Base sees 43 3 4 3 RIK Positioning RR Re Rex I Rr lh ren 43 3 4 3 1 Pseudorange versus carrier phase ambiguity 0065 43 3 4 3 2 Carrier Phase Positioning eee 44 Firmware User Manual for SSRC4 2 5 2 3 Septentrio LIST OF FIGURES atellite navigation 3 4 3 3 Integer Ambiguities RTK fixed 0 cece ee ee eee eee eee 44 3 4 3 4 Floating Ambiguities RTK float 0 ccc cece eee e eee e eee e eee eee 44 3 4 3 5 Datum Transformation cece cece ee 45 3 4 3 6 Antenria Effects accsusaseudes dee cody Pete E a 45 3 4 3 7 Practical Considerations eee 46 3 5 Receiver Autonomous Integrity Monitoring RAIM cece eee e eee eee ee eee 47 3 5 1 Integrity Algorithm ccc cece cece
18. 2 45 Septentrio 3 OPERATION DETAILS atellite navigation If no correction is applied the computed position refers to an average phase center with no easy link with the antenna physical element This average phase center fluctuates with time and cannot be used for accurate millimeter level positioning For high precision positioning the GNSS measurements need to be corrected in such a way that they all refer to a common and stable point in space That point is referred to as the antenna reference point ARP For convenience it is usually selected at the center of the bottom surface of the antenna The National Geodetic Survey has calibrated the offset from the PC to the ARP as a function of the elevation and of the frequency band for a large number of geodetic grade antennas NGS publishes calibration tables that can be downloaded from the following URL http www ngs noaa gov ANTCAL index shtml The antenna naming convention in such table is the one adopted by the IGS Central Bureau The receiver has a similar table in its non volatile memory This table can be upgraded following the standard upgrade procedure as described in section 2 17 the upgrade file is named ant info suf To let the receiver compensate for the phase center variations and compute the ARP position the user must specify the type of his her antenna using the setAntennaOffset command If the antenna is not specified or the antenna type is not present in the antenna c
19. 5 4 Up Time hours Figure 3 2 Effect of clock steering on the clock bias clock steering enabled at an up time of 1 hour Firmware User Manual for SSRCA 2 5 2 40 Septentrio 3 OPERATION DETAILS atellite navigation Bit 3 of the CommonF1ags field of the MeasEpoch SBF block indicates whether clock steering is active or not Note for the users of a GNSS constellation simulator When using a constellation simulator make sure to set the simulation time after January 01 2006 The receiver time will be incorrect before that date 3 4 Computation of Position Velocity and Time PVT Solution The receiver computes the position and velocity of its antenna and the time offset of the receiver based on the pseudoranges the Doppler measurements and if applicable the differential corrections The availability of the PVT depends on the number of available pseudoranges and Doppler measurements equal to the number of tracked satellites or a subset of them as specified by the setSatelliteUsage command the number of valid sets of broadcast ephemerides which are needed to compute the position velocity and clock bias for each tracked satellite the number of valid sets of fast and long term SBAS corrections and their age in the case of SBAS aided positioning the number of valid differential corrections and their age in the case of DGPS RTK positioning A position fix requires a minimum of 4 tracked satellites wit
20. Analyser functionality of RxControl The spectrum is computed from baseband samples taken at the output of the receiver s analog to digital converters These samples are available to the users in the BBSamples SBF block Firmware User Manual for SSRCA 2 5 2 31 Septentrio aki atellite navigation 2 16 Manage Users When connecting to the receiver users can remain anonymous or can log in using the login command What anonymous users can do depend on the connection type By default anonymous users have full control of the receiver This default configuration can be changed with the command setDefaultAccessLevel For example to prevent anonymous access to the web interface and to the ftp server you would use setDefaultAccessLevel none none CR RxControl File User Management Web Interface Receiver Administration gt User Management To perform actions not allowed to anonymous users you first need to authenticate yourself by entering a user name and a password through the Login command The list of user names and passwords and their respective access level is managed with the setUserAccessLevel command Login fails if the provided user name or password is not in that list Logged in users are granted one of the following access levels User or Viewer The User level allows full control of the receiver while the Viewer level only allows to view the configura tion The following explains how to add or
21. CMv2Output For instance to send only message types 1 and 3 to the NtripCaster use setRTCMv20utput NTR1 RTCM1 RTCM3 CR RxControl Communication gt Output Settings gt Differential Corrections gt RTCMv2 Web Interface Configuration Communication gt Output Settings gt Differential Corrections gt RTCMv2 3 Enable the output of RTCMv2 data on the NTR1 connection setDataInOut NTR1 RTCMv2 lt CR gt RxControl Communication gt Input Output Selection Web Interface Configuration Communication gt Input Output Selection 4 Closing the NTRIP connection is done with the following command setNTRIPSettings NTR1 off CR RxControl Communication gt NTRIP Settings Web Interface Configuration Communication gt NTRIP Settings See also section 2 5 for more information on configuring the receiver as a base station Firmware User Manual for SSRC4 2 5 2 20 Septentrio T atellite navigation 2 Configure an IP Server Port In this example we show how to configure the receiver such that any client connecting to TCP IP port 28785 will receive the NMEA GGA message at a 1 second interval 1 Configure one of the IP server connections see section 2 1 6 to listen to port 28785 Here we assume that the first IP server connection IPS1 is free setIPServerSettings IPS1 28785 CR RxControl Communication 7 Network Settings Web Interface Configuration Communication 7 Network Settings 2 Output th
22. EventA High2Low CR RxControl Navigation 7 Receiver Operation 7 Timing Web Interface Configuration Navigation gt Receiver Operation gt Timing Upon detection of a transition the receiver can output the time and or the position at the instant of the event see the external event SBF blocks in the SBF Reference Guide The following constraints must be observed to ensure proper event detection There must be no more than four events in any interval of 50 milliseconds all event pins con sidered The minimum time between two events on the same Event X input must be at least 5ms Missed events are flagged by the MISSEDEVENT bit in the ReceiverStatus SBF block Firmware User Manual for SSRCA 2 5 2 30 Septentrio jose atellite navigation 2 15 Monitor the RF Spectrum You can monitor the RF spectrum using the spectral analyzer in RxControl go to the View gt Spectral View menu This allows to detect the presence of interferences in the GNSS bands In the example shown below a narrowband interference at 1180 MHz is clearly visible r H usb3 serial Spectrum View bo la X View History Help 3T NE fale Continuous averaging 15 gt MAIN 1 212GHz v Stop Spectrum Samples e e LLL La L un e La Power 2 l LLLI 1 180 1 200 1 220 1 240 1 260 Frequency MHz Samples 1 MeanI0 64 Mean Q 0 21 RMSI 3 37 RMS Q 3 31 Figure 2 4 Spectral
23. IP17 Capabilities SBAS DGPSRover DGPSBase RTKRover RTKBase RTCMv23 RTCMv3x CMRv20 xPPSInput xPPSOutput TimedEvent InternalLogging APME RAIM INS PPP LBAND LBAS1 Meas Interval 10 ms PVT Interval 10 ms INS Interval 20 ms Figure 2 5 Example of receiver capabilities Firmware User Manual for SSRC4 2 5 2 35 Septentrio ee atellite navigation 2 19 Check or Change the Permission File The permission file lists which optional features such as GLONASS Galileo RTK are permitted on your receiver for how long they are permitted and in which region they are permitted The permission file is stored in the receiver s non volatile memory and can be checked with the command lstInternalFile Permissions or with RxControl by clicking Help gt Receiver Permissions or with the web interface select the Receiver tab and then Permissions Note that for a given feature to be enabled in the receiver it must be permitted and the hardware and firmware version must support it See also section 2 18 Each receiver is delivered with a permission file applicable to that receiver only To enable new options the user can order a new permission file to Septentrio and install it on his her receiver using the standard upgrade procedure see section 2 17 Firmware User Manual for SSRC4 2 5 2 36 Septentrio ee atellite navigation 2 20 Manage the Processor Load The processor load also referred to as the CPU us
24. PPS as generated position by receiver D xPPSOffset Receiver digital clock Figure 2 3 xPPS output granularity Although the position of the PPS pulse is computed accurately by the receiver the actual pulse is generated at the nearest tick of the internal receiver digital clock as illustrated in the figure above This leaves an offset noted D in the figure between the true xPPS pulse and the one actually generated by the receiver This offset can reach a few nanoseconds It is available in real time in the xPPSOffset SBF block To be able to align its xPPS output with the GNSS system time the receiver needs a fresh estimate of the GNSS time from its PVT solution If the last PVT solution is older than a prescribed timeout set by the setPPSParameters command no PPS pulse is generated In addition to align its PPS with UTC the receiver needs to have received the UTC offset parameters from the satellite navigation messages If these parameters are not available and the user has requested to align the xPPS with UTC no xPPS pulse is generated too Firmware User Manual for SSRCA 2 5 2 29 Septentrio Bowne atellite navigation 2 14 Time Tag External Events The receiver can time tag electrical level transitions on its Event X inputs with an accuracy of 20ns By default the receiver reacts on low to high transitions You can use the setEventParameters command to react on falling edge instead setEventParameters
25. SRC4 2 5 2 53 Septentrio atellite navigation APPENDIX A NMEA RTCM AND CMR OVERVIEW PSSN RBP Septentrio Proprietary Sentence Rover Base Position Field Description PSSN RBP Start of sentence hhmmss ss UTC of RBP HoursMinutesSeconds DecimalSeconds XXXXXX Date ddmmyy X X North True baseline component positive when base is north of rover meters X X East baseline component positive when base is east of rover meters X X Up baseline component positive when base is higher than rover meters XX Number of satellites used for baseline computation Quality indicator 0 Invalid X 2 DPGS 4 RTK Float RTK ase motion indicator X 0 Static base 1 Moving base X X Correction Age seconds cc Rover serial number XXXX Base station ID hh Checksum delimiter and checksum field lt CR gt lt LF gt End of sentence PSSN RBD Septentrio Proprietary Sentence Rover Base Direction Field Description PSSN RBD Start of sentence hhmmss ss UTC of RBD HoursMinutesSeconds DecimalSeconds XXXXXX Date ddmmyy X X Azimuth of the base as seen from rover 0 to 360 increasing to wards east degrees True X X Elevation of the base as seen from rover 90 to 90 degrees XX Number of satellites used for baseline computation Quality indicator 0 Invalid X 2 DPGS 4 RTK Float RTK ase motion in
26. SSRCA 2 5 2 Septentrio i Bown atellite navigation 2 How To This chapter contains step by step instructions to help you with typical tasks It does not provide a complete overview of the receiver s operations but rather an introduction to different operation modes Please refer to the Command Line Interface Reference Guide for a complete description of the command set You can enter user commands in many different ways You can enter commands manually through one of the receiver input ports see section 2 1 In this chapter user commands are referred to by their full name for readability When typing the command you can always use the short mnemonic equivalent to save typing effort For instance instead of typing setCOMSettings you can type scs See the Command Line Interface Reference Guide to know the mnemonic equivalent of a given command e You can type commands or mnemonics in the console window of RxControl menu Tools gt Expert Console You can also type commands or mnemonics from the web interface Receiver Administration gt Expert Console All commands can also be accessed graphically through menus in RxControl and in the web interface Depending on the capabilities of your particular receiver see section 2 18 some of the features A described here may not be supported Firmware User Manual for SSRC4 2 5 2 9 Septentrio aw atellite navigation 2 1 Connect to the Receiver 2 1 1
27. age is reported in the ReceiverStatus SBF block and can be viewed on the main window of RxControl and of the web interface Receiver operation becomes unreliable when the CPU usage gets higher than 90 CPU overload may lead to software errors and it is typical that the SOFTWARE error bit in the ReceiverStatus SBF block be set if that happens use the command 1stInternalFile Error to reset that bit High processor load is typically observed during high rate RTK or multi base DGPS operation A number of actions can be undertaken to free up CPU resources Lower the output rate of SBF blocks see the setSBFOutput command and only enable those blocks needed for your application Limit the number of satellites being tracked for instance by increasing the elevation mask setElevationMask command Disable SBAS or GLONASS tracking if SBAS or GLONASS is not required for your applica tion using the setSatelliteTracking command Disable the tracking of signals not needed for your application e g GPS L2C using the set SignalTracking command Disable the ASCIIDisplay output with the setDataInOut command this display is pri marily meant for temporary inspection of the receiver operation and for debugging Firmware User Manual for SSRCA 2 5 2 37 Septentrio 3 OPERATION DETAILS atellite navigation 3 Operation Details This Chapter describes the key processes implemented in the receiver and explains how they can be configured
28. al ports and log the replies from that sensor In the following example we show how to retrieve meteo data every 10 seconds from a meteo sensor connected to the receiver s COM2 port 1 Tell the receiver which command to use to query the external sensor and the interval at which this command must be sent to the sensor For instance for a MET3 MET4 compatible sensor the command 0100P9 CR LF queries the meteo data Assuming you want to get meteo data at a 10 second interval enter the following command setPeriodicEcho com2 A x0100P9 CR LF seclO0 CR RxControl Communication gt Output Settings gt Periodic Echo Message Web Interface Configuration Communication gt Output Settings gt Periodic Echo Message 2 Enable unformatted ASCII input on COM2 to receive the replies from the meteo sensor setDataInOut COM2 ASCIIIn lt CR gt RxControl Communication gt Input Output Selection Web Interface Configuration Communication gt Input Output Selection The replies from the meteo sensor containing the temperature pressure and humidity are available in the ASCIIIn SBF block Refer to section 2 3 to know how to output and log SBF blocks You can convert a SBF file containing ASCII In SBF blocks to RINEX using the sb 2rin program or the SBFConverter graphical tool These tools support MET3 MET4 compatible sensors Firmware User Manual for SSRC4 2 5 2 28 Septentrio i Bowne atellite navigation 2 13
29. alibration file the receiver cannot make the distinction between phase center and ARP and the position accuracy is slightly degraded especially in the height component The point to be positioned is the marker see figure 3 3 The offset between the ARP and the marker is a function of the antenna monumentation It must be measured by the user and specified with the setAntennaOffset command The absolute position reported in the PVTCartesian and PVTGeodetic SBF blocks is always the marker position The base to rover baseline coordinates in the BaseVectorCart and BaseVectorGeod SBF blocks is from ARP to ARP unless the receiver is not able to properly compensate for the phase center variation at base or rover Details on this is to be found in the description of these blocks in the SBF Reference Guide 3 4 3 7 Practical Considerations The reasons for possible low accuracy or availability of the RTK position are Multipath Ionosphere decorrelation Loss of lock e L2 availability e RTCM CMR availability To ensure high accuracy and availability care must be taken that the above error sources have as little impact as possible This can be achieved by using survey grade antennas and choosing a suitable location for the base station with an unobstructed view of the sky Since low elevation satellites are more prone to loss of lock and multipath it is also recommended to use an elevation mask of 10 degrees In moving base app
30. artepoch ndepoch n type MET s D v R3 R210 x systems a antenna V f input file mandatory Name of the SBF file o output fil Name of the RINEX file If not provided the RINEX convention is applied ssssdddf yyt With the o copy option the name of the RINEX file is a copy of the name of the SBF file with the last character being set to O N Gor L according to the RINEX file type With the o copybase option the name of the RINEX file is a copy of the name of the SBF file with the last 3 characters being set to yyt 2 digit year and type according to the RINEX convention R3 Generate a RINEX version 3 02 file instead of version 2 11 R210 Generate a RINEX version 2 10 file instead of version 2 11 i interval Interval in the RINEX obs and meteo file in seconds by default the interval is the same as in the SBF file b startepoch Time of first epoch to insert in the RINEX file Format yyyy mm dd hh mm ss or hh mm ss e endepoch Last epoch to insert in the RINEX file Format yyyy mm dd hh mm ss or hh mm ss s Add the Sx obs types for the SNRs in dB Hz Allow comments in the RINEX file from the Comment block only applicable for RINEX v2 11 and v2 10 C commentstr Add the specified comment string to the RINEX obs header The comment string must not be longer than 240 characters Enclose the string between quotes if it con
31. cece cece eee esee esee 48 3 5 2 Internal and External Reliability Levels 0 e cece e ee eee 49 A NMEA RTCM AND CMR OVERVIEW 51 A l Proprietary NMEA Sentences cee cece eee ce eee eI heme 53 B sBF2RIN UTILITY 56 List of Figures 1 1 RxControl main window 0 ccc cece e eee e e ee e memes 8 2 1 Web interface main window sssssssseeeee I eene 12 2 2 Download Internal Files from RxControl 00 0 cece e ence eee cee ee eee en ennee eens 25 2 3 XPPS output eranularity ss isi epe rex PINNAE UP RR veda bebe Linh tee as 29 2 4 Spectral Analyser functionality of RxControl seseee een ennee eens 31 2 5 Example of receiver capabilities csse eem 35 3 1 Example of the evolution of the receiver time offset with respect to the GNSS time in free running MOdE cense bi eunea eee ence e eee e e memes sees 40 3 2 Effect of clock steering on the clock bias clock steering enabled at an up time of 1 NOUT TH 40 3 9 Antenna mount ood e elaine hated UU RED ANNO ie 45 3 4 Statistical test outcomes iiis aeee rie aap rE teen Rr ebeb EY gx REY TE IPIE ERE cee beUa 48 Firmware User Manual for SSRCA 2 5 2 4 Septentrio LIST OF ACRONYMS atellite navigation List of Acronyms APME ARP ASCII CMR CPU CR DGPS DHCP DOP EGNOS ESTB FPGA GLONASS GNSS GPS GPX GUI HERL HPL IGS IMU INS KML LAMBDA LED MDB MOPS MT NMEA OTF PC PPP PPS PVT RAIM
32. ct which SBAS satellite should provide the corrections to the PVT and override the automatic selection by the receiver and how to deal with subtleties of the SBAS navigation message This is done by the setSBASCorrections command For instance to only accept corrections from EGNOS PRN126 use setSBASCorrections S126 lt CR gt RxControl Navigation gt Positioning Mode gt SBAS Corrections Web Interface Configuration Navigation gt Positioning Mode gt SBAS Corrections 5 Optionally it is possible to include the range to SBAS satellites as an additional ranging source for the PVT This is not done by default as the SBAS ephemeris accuracy is poor 100 m error However to do so use setSatelliteUsage SBAS lt CR gt RxControl Navigation gt Advanced User Settings gt PVT gt Satellite Usage Web Interface Configuration Navigation gt Advanced User Settings gt PVT gt Satellite Usage To compute a fully SBAS aided position the receiver has to receive and decode the following infor mation Long term corrections corrections to the satellite orbit and clock as specified in the GPS ephemerides Fast corrections short term satellite clock error Vertical ionospheric delays over the SBAS ionosphere grid surrounding the receiver position Due to the structure and order of the SBAS messages it can take up to 2 5 minutes before the long term and fast corrections are available to the receiver and up to 5 minutes before th
33. de described below If you need to upgrade several components at once e g the GNSS firmware and the FPGA config uration you will need to repeat the upgrade procedure for each of the components The following upgrade order is recommended 1 GNSS firmware 2 FPGA configuration 3 permission file To manually upgrade the receiver follow this procedure 1 Connect to the receiver through one of its serial ports only serial ports support the manual upgrade procedure 2 Power cycle the receiver When booting the receiver outputs the following prompt STE Septentrio SSRC4 SN lt serialnr gt is booting r n where lt serialnr gt is the serial number of your particular receiver 3 After the above prompt is output you have one second to break the automatic boot sequence This is done by sending the following sequence of characters to the receiver GARx saub CR 4 If the boot is effectively interrupted the receiver outputs the U Boot gt prompt At that prompt enter the following command loads CR 5 Transfer the srec upgrade file in text mode to the receiver Typically on Windows use Hyperterminal select the Transfer gt Send Text File menu The receiver outputs a series of dots then a summary of the transfer Firmware User Manual for SSRCA 2 5 2 33 Septentrio ee atellite navigation 6 When the file transfer is done issue the following command to permanently write the data into the non v
34. default configuration you can reconfigure it as follows 1 If you want to use the SBAS corrections to improve the PVT accuracy you need to configure the PVT in SBAS mode For instance the following command instructs the receiver to compute a PVT using the SBAS corrections when available and to fall back to the standalone mode otherwise setPVTMode Rover StandAlone SBAS lt CR gt RxControl Navigation gt Positioning Mode gt PVT Mode Web Interface Configuration Navigation gt Positioning Mode gt PVT Mode 2 Make sure that the troposphere model is as prescribed by the RTCA DO 229 standard This is the default setting but in case the receiver is not in its default configuration you should use setTroposphereModel MOPS MOPS lt CR gt RxControl Navigation gt Receiver Operation gt Position gt Atmosphere Web Interface Configuration Navigation gt Receiver Operation gt Position gt Atmosphere 3 It is recommended to leave the ionospheric model selection to auto In particular using the Klobuchar model in SBAS mode will lead to degraded performance and is not recommended setIonosphereModel auto lt CR gt RxControl Navigation gt Receiver Operation gt Position gt Atmosphere Web Interface Configuration Navigation gt Receiver Operation gt Position gt Atmosphere 4 By default the receiver selects the SBAS satellite with the most SBAS corrections available It is possible to force the receiver to sele
35. delete a user 1 Check the current user list by entering the following command getUserAccessLevel CR RxControl File User Management Web Interface Receiver Administration gt User Management The reply to this command looks like UserAccessLevel Userl admin R46NCG User UserAccessLevel User2 Viewer UserAccessLevel User3 Viewer 2 In the example shown above only one user is defined User1 with user name admin For security reasons the password shown here R46NCG is random and does not correspond to the actual password It can be seen that the level of access of the admin user is User that particular user has full control of the receiver To add a new user john with password abc123 and to give full access to that user select a free user index e g User2 in the above example and type setUserAccessLevel User2 john abci23 User CR 3 You can add up to eight users in this way Deleting a user involves entering an empty string as user name and password For example to delete the admin user from the above list use setUserAccessLevel Userl1 CR The user list also applies to FTP accesses FTP users having the User access right are allowed to delete files from the SD memory card via FTP while Viewer FTP users can only download files Firmware User Manual for SSRCA 2 5 2 32 Septentrio jw atellite navigation 2 17 Upgrade the Rece
36. dicator X 0 Static base 1 Moving base X X Correction Age seconds c c Rover serial number XXXX Base station ID hh Checksum delimiter and checksum field lt CR gt lt LF gt End of sentence Firmware User Manual for SSRC4 2 5 2 54 Septentrio atellite navigation APPENDIX A NMEA RTCM AND CMR OVERVIEW PSSN RBV Septentrio Proprietary Sentence Rover Base Velocity Field Description PSSN RBV Start of sentence hhmmss ss UTC of RBV HoursMinutesSeconds DecimalSeconds XXXXXX Date ddmmyy X X Rate of change of baseline vector rover to base north compo nent m s X X Rate of change of baseline vector rover to base east component m s X X Rate of change of baseline vector rover to base up component m s XX Number of satellites used for baseline computation Quality indicator 0 Invalid X 2 DPGS 4 RTK Float RTK ase motion indicator X 0 Static base 1 Moving base X X Correction Age seconds cc Rover serial number XXXX Base station ID hh Checksum delimiter and checksum field lt CR gt lt LF gt End of sentence Firmware User Manual for SSRC4 2 5 2 55 Septentrio atellite navigation Appendix B sb 2rin Utility APPENDIX B SBF2RIN UTILITY sbf2rin converts a binary SBF file to the widely used RINEX ASCII format RINEX v2 10 v2 11 and v3 02 are supported An SBF file is a file containing a s
37. e GGA NMEA message to the IPS1 connection at a 1 Hz rate setNMEAOutput Streaml IPS1 GGA secl CR RxControl Communication gt Output Settings gt NMEA Output gt NMEA Output Intervals Web Interface Configuration Communication gt Output Settings gt NMEA Output gt NMEA Output Intervals 3 Make sure that NMEA output is enabled on the IPS1 connection It is enabled by default but in case your receiver is not in its default configuration you should invoke setDataInOut IPS1 NMEA CR RxControl Communication 7 Input Output Selection Web Interface Configuration Communication 7 Input Output Selection 4 You will need to reset the receiver for the new IP server configuration to take effect exeResetReceiver Soft none CR RxControl File gt Reset Receiver Web Interface Receiver Administration gt Reset Receiver A way to check the IP server functionality is to enter the URL http ssrc snxxxxxxx 28785 in your preferred web browser replace ssrc snxxxxxxx by the hostname of your particular re ceiver You should see the NMEA GGA message coming every second Note that up to eight clients can concurrently connect to the same IP server port Firmware User Manual for SSRCA 2 5 2 21 Septentrio i Bown atellite navigation 2 8 Configure the SBAS Operation Your receiver is by default configured to make optimal use of the wide area corrections sent by these satellites In case the receiver is not in its
38. e ionospheric grid Minimum Operational Performance Standards for Global Positioning Wide Area Augmentation System Airborne Equipment RTCA DO 229C November 28 2001 Firmware User Manual for SSRCA 2 5 2 22 Septentrio oe atellite navigation is available Hence it is normal that the receiver cannot yield an SBAS aided position immediately after the lock on an SBAS satellite For more details on SBAS positioning refer to section 3 4 1 Firmware User Manual for SSRC4 2 5 2 23 Septentrio jw atellite navigation 2 9 Log SBF or NMEA on the SD Memory Card Enabling SBF or NMEA logging on the internal memory card involves the following steps 1 By default the receiver logs SBF blocks into a file named 10g sb and NMEA sentences into a file named log nma You can specify any other fixed or auto incrementing file name or you can select the IGS RINEX naming convention where the file name automatically changes every fifteen minutes hour six hours or day For instance to let the receiver create daily files use setFileNaming DSK1 1GS24H CR RxControl Logging gt Internal Logging Settings Web Interface Logging Internal Logging Settings If the file name you selected already exists the receiver will append new data at the end of the existing file 2 Use the command setSBFOutput to define which SBF blocks need to be logged for NMEA use setNMEAOutput instead and at which interval see also secti
39. e week number is decoded from the GPS or Galileo SIS which can be either simultaneously with the time of week or several seconds later the WNc counter is set and starts counting After the first position and time fix has been computed for which measurements from at least 4 satellites are required TOW is set to within X milliseconds of GNSS time This is done by introducing a jump of an integer number of milliseconds in the TOW counter X is the maximal allowed offset between the receiver time and GNSS time and is set by the setClockSyncThreshold command by default X 0 5ms This initial clock synchro nization leads to a simultaneous jump in all the pseudorange and carrier phase measurements The level to which the receiver time is synchronized with the GNSS system time is given by three status bits TOWSET WNSET and FINETIME available both in the ReceiverTime SBF block and the ReceiverStatus SBF block The receiver clock can be configured in free running mode or in steered mode using the command setClockSyncThreshold Firmware User Manual for SSRCA 2 5 2 39 Septentrio 3 OPERATION DETAILS atellite navigation 3 3 4 Free Running Clock In free running mode the receiver time slowly drifts with respect to GNSS time The receiver contin uously monitors this time offset this is the clock bias term computed in the PVT solution as provided in the RxC1kBias field of the PVTCartesian and PVTGeodetic SBF bl
40. easurements The setHealthMask command can be used to filter out measurements from unhealthy satel lites these measurements will not be used by the PVT algorithm nor will they be included in the MeasEpoch SBF block To further reduce the code measurement noise the receiver can be ordered to smooth the pseu dorange by the carrier phase This technique sometimes referred to as a Hatch filtering al lows to reduce the pseudorange noise and multipath It is controlled by the setSmoothingIn terval command and is disabled by default The setMultipathMitigation command can be used to enable or disable the mitigation of multipath errors in the pseudorange It is enabled by default For advanced applications or in depth signal analysis the MeasExtra SBF block contains various additional data complementing the MeasEpoch SBF block Among other things this block reports the multipath correction applied to the pseudorange allowing one to recompute the original pseudor ange and the observable variances Firmware User Manual for SSRCA 2 5 2 38 Septentrio 3 OPERATION DETAILS atellite navigation 3 2 1 Pilot vs Data Component Most modern GNSS signals consist of two components a so called pilot component and a data com ponent For such signals the measurements are based on the pilot component for optimal perfor mance In particular the reported C N value is that of the pilot component only The table below indicates wh
41. ect when it is located outside the service area and adjust the PVT accuracy accordingly Without these messages the receiver has no means of knowing the extent of the service area The DO 229 standard defines two operation modes for SBAS positioning en route and precision approach As the integrity requirements for precision approach are significantly higher the HPL VPL values in this mode are higher and more importantly the time out interval of the corrections is shorter which can lower the availability of a position The default operation of the receiver is en route and the user has the choice to select precision approach using the setSBASCorrections command An SBAS provider can transmit MTOO to reset the data transmission in case of severe errors However this message is also transmitted for test purposes For proper operation during a test phase such as ESTB it is recommended to ignore the MTOO which can be done using the set SBASCorrections command The GEOCorrections SBF block contains all the corrections and their variances as used in the PVT computation This block allows for a detailed analysis of the SBAS PVT computation in the receiver Firmware User Manual for SSRCA 2 5 2 42 Septentrio 3 OPERATION DETAILS atellite navigation 3 4 2 DGPS Positioning Single and Multi Base DGPS Differential GPS reduces the effect of GNSS system errors by the use of range corrections GNSS system errors such as orbit and atmo
42. ess the receiver The Windows USB diver can be installed through the RxTools software suite On Linux the standard Linux CDC ACM driver can be used to emulate one serial port Most terminal emulation programs will make no distinction between virtual and native COM ports Note that the port settings baud rate etc for virtual serial ports are not relevant and can be left in their default configuration in the terminal emulation program The main advantage of the USB connections with respect to the native COM ports is that they support a much larger bandwidth 2 1 3 Via a TCP IP Port TCP IP connections allow remote control of the receiver and are potentially much faster than serial connections Up to eight independent TCP IP connections can be opened in parallel through port 28784 the port number can be changed with the command set IPPortSettings The receiver can be configured for dynamic or fixed IP address allocation The default is dynamic ad dress allocation using the DHCP protocol The hostname is ssrc snxxxxxxx where xxxxxxx Firmware User Manual for SSRCA 2 5 2 10 Septentrio i Bowne atellite navigation consists of the last seven digits of the serial number of the receiver The hostname is also printed on a label on the bottom side of the receiver Dynamic IP address allocation requires the availability of a DHCP server in your local network In the absence of a DHCP server or when a fixed IP address is desirable it
43. face Configuration Communication gt Input Output Selection To stop transmitting RTCM messages enter the following command setDataInOut COM2 none CR RxControl Communication 7 Input Output Selection Web Interface Configuration Communication 7 Input Output Selection Note that even in static mode the receiver computes a PVT solution to estimate the clock bias Dis abling the PVT for example by using the setSatelliteUsage command prevents the receiver from outputting RTK corrections Firmware User Manual for SSRCA 2 5 2 19 Septentrio i Bown atellite navigation 2 6 Configure the Receiver as a NTRIP Server In the example below we show how to configure the receiver to send RTCMv2 corrections to a NtripCaster using the following parameters NtripCaster hostname ntrip example com NtripCaster port 2101 User name password for basic authentication SEPT PASSWD Mount Point LEUV1 1 Configure one of the NTRIP connections see section 2 1 6 for communication with the Ntrip Caster Here we assume that the first NTRIP connection NTR1 is free and can be used for that purpose SetNTRIPSettings NTR1 Server ntrip example com 2101 SEPT PASSWD LEUV1 CR RxControl Communication 7 NTRIP Settings Web Interface Configuration Communication 7 NTRIP Settings 2 By default for RTCMv2 the receiver is configured to send message types 1 3 18 19 and 22 This can be changed by using the command set RT
44. h associated ephemerides When only 3 satellites are available or in case of bad satellite geometry large DOP the receiver will compute a 2D position fix assuming that the ellipsoidal height is the same as for the latest 3D fix The mode of position fix is reported by the Mode field in the PVT related SBF blocks If less than 3 satellites are available the receiver does not compute a position When a PVT solution is not available PVT related SBF blocks are still output with all the numeric fields set to Do Not Use values and with the Error field set to indicate the source of the problem The accuracy of the PVT depends on The signal level measurements with a C N of 32 dB Hz will exhibit considerably more noise than measurements with a C N of 52 dB Hz Hence it is recommended to use a high quality antenna The geometry of the satellite constellation expressed in the DOP values these values indicate the ratio of positional errors to range errors and are computed on the basis of the error propaga tion theory When the DOP is high the accuracy of positioning will be low The number of available satellites the more satellites are available the lower the DOP Mea surement redundancy also enables better outlier detection Multipath errors on the pseudorange measurements multipath errors can be largely attenu ated by enabling the APME multipath mitigation method see setMultipathMitigation and or using code smoothing see setSmoothingInte
45. he sb 2rin program or the SBFConverter graphical tool Firmware User Manual for SSRCA 2 5 2 26 Septentrio aki atellite navigation 2 11 FTP Push SBF and RINEX files Itis possible to configure the receiver to automatically send internally logged SBF or RINEX files to a remote FTP server FTP Push This is done with the setFTPPushSBF and setFTPPushRINEX commands respectively For example to automatically FTP RINEX files to the directory mydata rin on the remote server myftp com with username myname and password mypwd you would enter the following com mand SetFTPPushRINEX myftp com mydata rin myname mypwd CR RxControl Logging gt Internal RINEX Logging gt RINEX FTP Push Options Web Interface Logging Internal RINEX Logging gt RINEX FTP Push Options To FTP push SBF files to the same location you would use setFTPPushSBF myftp com mydata rin myname mypwd lt CR gt RxControl Logging gt Internal RINEX Logging Web Interface Logging Internal RINEX Logging Note that all files are put in the same remote directory mydata rin in this example even if they are internally logged in daily directories FTP push does not create daily folders on the remote server Firmware User Manual for SSRC4 2 5 2 27 Septentrio jw atellite navigation 2 12 Communicate with a Meteo Sensor The receiver can send periodical queries to an external sensor such as a meteo sensor connected to one of its seri
46. ich signal component is used for all signals having a pilot and data component Signal component being used for measurement generation Galileo L1 L1 C Galileo E5a E5a Q Galileo E5b E5b Q Galileo ESAItBOC ESAItBOC Q GPS QZSS L2C L2C L GPS QZSS L5 L5 Q 3 3 Time Management All time tags in the receiver refer to the receiver time scale The receiver is designed in such a way that the receiver time is kept as close as possible to the selected GNSS system time GPS or Galileo as prescribed by the setTimingSystem command Internally the receiver time is kept in two counters the time of week counter in integer milliseconds TOW and the week number counter WNc WNc counts the number of complete weeks elapsed since January 6 1980 even if the selected GNSS system time is Galileo The TOW and WNc counters are reported in all SBF blocks The synchronization of TOW and WNc with the GNSS system time involves the following steps Upon powering up the receiver TOW and WNc are assumed unknown and set to a Do Not Use value in the SBF blocks The transmission time of week and week number are coded in the GPS or Galileo navigation messages As soon as the first time of week is decoded from the GPS or Galileo signal in space SIS the TOW counter is initialized to within 20 ms of GNSS system time and starts counting This is also the time when the receiver starts generating measurements As soon as th
47. ir results in the coordinates of local datums instead of global or regional datums If your RTK service provider transmits coordinate transformation parameters in RTCM v3 x message types 1021 to 1023 the receiver can compute coordinates in the applicable local datum Local datum coordinates are reported in the PosLocal SBF block while the PVTCartesian and PVTGeodetic SBF blocks always contain untransformed coordinates The following conditions must be met for the receiver to provide a valid position in the PosLocal SBF block the receiver must be in RTK positioning mode e the usage of RTCM v3 x MT1021 1023 must be enabled by the command setRTCMv3Usage these messages are enabled by default complete datum transformation parameters must have been received from the RTCM stream the position must be in the area of validity of the transformation parameters 3 4 3 6 Antenna Effects To achieve the highest precision in RTK operations it is essential to take antenna effects into account PC Marker Figure 3 3 Antenna mount The GNSS measurements pseudoranges and carrier phases observables refer to a theoretical point in space called the phase center noted PC in figure 3 3 The position of this point is dependent on the elevation of the satellite and on the frequency band It varies with time and it is different for L1 and L2 The phase center variation can reach a few centimeters Firmware User Manual for SSRC4 2 5
48. is defined as explained in section 2 1 3 For example if your receiver s hostname is ssrc sn1234567 simply use the following URL in your preferred web browser http ssrc sn1234567 Firmware User Manual for SSRCA 2 5 2 11 Septentrio Howtos atellite navigation N z I ot logged in status Login Product AsteRx3_OEM Mode RTK Fixed CPU 49 DiffCorr Platform SSRC3 System GPS GLO Uptime 0d 00 42 30 SN 2003871 Info Logging x Connected Configuration Logging Help Week Number 1642 Time Of Week 126016 gt Receiver Interface Mode RIK Fixed b Administration Value Standard Deviation m Velocity m s Velocity Standard Deviation m s Latitude N50 50 53 6202 0 00 0 00 0 02 Longitude 4 43 54 3945 0 00 0 00 0 01 Height 128 71 0 01 0 00 0 03 Figure 2 1 Web interface main window From the main window you can select one of the following tabs Receiver select this tab for receiver administration tasks such as checking the receiver capabilities upgrading the receiver firmware managing the configuration files managing the users etc Status select this tab to monitor the status of the receiver current position satellite tracking status DOP etc Configuration select this tab to configure the communication ports and network settings or to change the GNSS and navigation settings Logging select this tab t
49. is iterative process continues until either the overall model test along with the associated w tests are accepted or until the w tests for each individual measurement are accepted with a rejected overall model test In the latter case an integrity loss is declared in the former case integrity is available Note that under extreme circumstances the interactive D I A process can also halt due to insufficient available measurements for testing after removal of outliers In this case the too many outliers error is reported in the PVT related SBF blocks For the evaluation of the w test statistic the following inequality is verified i EE lt Wi lt Hk Ce i where e w is the w test statistic for the ith satellite e ej is the residual for the ith satellite Ge is the standard deviation of the residual for the ith satellite kl is the test threshold yielding a probability o of false alarm The probability of false alarm of the w test is selectable by the user with the Pfa argument of the SetRAIMLevels command The test threshold is computed by the receiver with the assumption that the w test statistic is dis tributed as a Normal distribution For instance if Pfa is set to 10 residuals larger than 1 64 sigma are flagged as outliers If Pfa is 0 0196 the threshold will be 3 89 3 5 2 Internal and External Reliability Levels To assess the impact of undetected measurement errors on the computed position the mi
50. is possible to disable the DHCP client and use a fixed address Switching between fixed and dynamic IP address allocation is typically done as follows taking the fictitious example of setting the static IP address to 192 168 2 2 the netmask to 255 255 255 0 and the gateway to 192 128 2 1 1 Specify the new IP settings with the command set IPSettings setIPSettings Static 192 168 2 2 255 255 255 0 192 128 2 1 CR RxControl Communication 7 Network Settings Web Interface Configuration Communication 7 Network Settings 2 Reset the receiver for the new settings to take effect exeResetReceiver soft none CR RxControl File gt Reset Receiver Web Interface Receiver Administration gt Reset Receiver A simple way to check the TCP IP connection is to use the telnet program specifying port number 28784 For example if your receiver has serial number 1234567 communication with port 28784 can be established by using telnet ssrc sn1234567 28784 From that moment on everything that is typed is sent to the receiver and the replies from the re ceiver are displayed on the screen To suspend the connection and return to the telnet prompt type Ctrl J RxControl can communicate with remote receivers over a TCP IP connection select TCP IP Connec tion option when opening the connection to the receiver 2 1 4 Via a Web Browser The receiver can be controlled and configured using a web browser The hostname or fixed IP address
51. iver Upgrading the receiver is the process of installing a new GNSS firmware a new FPGA configuration a new permission file see section 2 19 or a new antenna calibration file see section 3 4 3 6 Upgrading the GNSS firmware can clear the receiver configuration stored in non volatile memory see section 2 4 Please make sure to reconfigure your receiver e g baud rate settings elevation masks LBAS1 access code etc after an upgrade There are several ways to upgrade the receiver 1 By using the RxControl graphical interface go to the Tools menu Upgrading over USB or TCP IP is supported from firmware versions 2 3 Older versions only supported upgrading over serial ports 2 From the web interface go to Receiver Administration 7 Upgrade Firmware This requires to log in as a user with the User access level see section 2 16 3 By commanding the receiver to upgrade itself by fetching the upgrade file from a remote FTP server This is done with the command exeFTPUpgrade RxControl File gt Upgrade Receiver from FTP Web Interface Receiver Administration gt Upgrade Receiver from FTP 4 By manually uploading upgrade files via one of the serial ports This upgrade procedure is explained below Upgrade files are provided by Septentrio in two different formats suf and srec The suf file must be used for RxControl web and FTP based upgrades while the srec file must exclusively be used for the manual upgra
52. lection Web Interface Configuration Communication gt Input Output Selection 2 Scheduling SBF blocks for output is done by defining so called SBF streams Up to 10 SBF streams can be defined by the user A stream consists of a set of SBF blocks that need to be output at a given rate on a given connection descriptor By default all streams are empty and no SBF blocks are output For our example we will need to use two streams the first one for the MeasEpoch and PVTCartesian SBF blocks at a 10 Hz rate and the second one for the GPSNav at the OnChange rate Defining these SBF streams involves the setSBFOut put command setSBFOutput Stream1 USB2 MeasEpoch PVTCartesian msec100 CR setSBFOutput Stream2 USB2 GPSNav OnChange CR RxControl Communication gt Output Settings gt SBF Output Web Interface Configuration Communication gt Output Settings gt SBF Output If you want to output the same SBF blocks at the same rate on another connection say COM1 you will need to use two additional streams for instance St ream3 and Stream4 setSBFOutput Stream3 COM1 MeasEpoch PVTCartesian msec100 CR setSBFOutput Stream4 COM1 GPSNav OnChange CR 3 To stop outputting SBF on a given connection you can either redefine or empty the correspond ing streams setSBFOutput Streaml USB2 none CR setSBFOutput Stream2 USB2 none CR A second possibility is to disable all SBF messages on that connection setDataInOut USB2
53. lications it is recommended to keep the baseline length short lt 1km The availability of fixed ambiguities increases significantly with the use of L2 carrier phase measure ments When in single frequency operation it is advised to force the receiver to remain in RTK float mode using the setPVTMode command Firmware User Manual for SSRCA 2 5 2 46 Septentrio 3 OPERATION DETAILS atellite navigation 3 5 Receiver Autonomous Integrity Monitoring RAIM The receiver features RAIM to ensure the integrity of the computed position solution provided that sufficient satellites are available The RAIM algorithm consists of three steps detection identification and adaptation or shortly D I A Detection an overall model statistical test is performed to assess whether an integrity problem has occurred Identification statistical w tests are performed on each individual measurement to assess whether it should be marked as an outlier Adaptation measurements marked as an outlier are removed from the position computation to restore the integrity of the position solution This step is only applied if outliers have been detected in the detection step If the overall model statistical test fails the RAIM module attempts to recover from the integrity failure by removing the responsible measurement s identified in the second step As a consequence the RAIM module will generally increase the continuity of integrity The Integri
54. lti base DGPS can quickly overload the receiver processor if the number of base stations is large 3 4 3 RTK Positioning RTK which stands for Real Time Kinematic is a carrier phase positioning method where the carrier phase ambiguities are estimated in a kinematic mode it does not require static initialization To work in RTK mode the receiver requires the reception of RTK messages Both the RTCM and the CMR message formats are supported The base station providing these RTK messages can be either static or moving Multiple base RTK is not supported by default the receiver selects the nearest base station if more than one base station is available In RTK mode the absolute position is reported in the PVTCartesian or PVTGeodetic SBF blocks and the baseline vector is reported in the BaseVectorCart and BaseVectorGeod SBF blocks 3 4 3 1 Pseudorange versus carrier phase ambiguity Pseudoranges typically have a thermal noise in the decimeter range The resulting position accuracy is in the meter range if multipath and orbit errors are taken into account On the other hand the phase measurements from the carrier signal are very precise with a millimeter level precision However phase measurements are by nature ambiguous Consider the dial of a clock as an analogue if only the big hand would be available on the dial we would only know how many minutes have gone by Only by counting the hour crossovers every 60 minutes we could gain
55. nd so forth The S option has no effect if the o option is used v Run in verbose mode V Display the sbf2rin version Firmware User Manual for SSRC4 2 5 2 58
56. ng and Measurements gt Smoothing Web Interface Configuration Navigation 7 Receiver Operation 7 Tracking and Measurements 7 Smoothing 9 According to the RTCM standard an RTK base station must keep its clock error under 1 1 milliseconds The CMR standard is even more stringent with a prescribed maximum clock error of 0 5ms which is the receiver default In case the receiver is not in its default configuration you can restore the default setting by using setClockSyncThreshold usec500 CR RxControl Navigation gt Receiver Operation gt Timing Web Interface Configuration Navigation gt Receiver Operation gt Timing 10 By default the receiver is configured to output all RTCM and CMR messages necessary for DGPS and RTK operation In case the default has been modified use the commands set RTCMv2Output setRTCMv3Output or setCMRv2Output to specify which types of messages to enable for output For instance to output RTCM2 x messages 1 and 3 on COM2 use setRTCMv2Output COM2 RTCM1 RTCM3 CR RxControl Communication gt Output Settings gt Differential Corrections gt RTCMv2 Web Interface Configuration Communication gt Output Settings gt Differential Corrections gt RTCMv2 11 The connection which needs to output the RTCM stream must be configured to do so For instance to enable RTCM 2 x output through COM2 use setDataInOut COM2 RTCMv2 CR RxControl Communication gt Input Output Selection Web Inter
57. nimal de tectable bias MDB in the range domain is computed and propagated to the position domain The MDB describes the internal reliability of the corresponding w test It is a measure of the range error that can be detected with a given probability of missed detection It is computed as follows for each satellite neglecting the probability that the biased measurement falls on the left hand side of the non biased distribution shown in Figure 3 4 1 2 where oy is the standard deviation of the range measurement of the 7th satellite og is the standard deviation of the estimator for the measured range of the ith satellite Firmware User Manual for SSRCA 2 5 2 49 Septentrio 3 OPERATION DETAILS atellite navigation Ag is the non centrality parameter which depends upon the probability of false alarm of the w test and the probability of missed detection The user can select the probability of missed detection acceptable for his her application with the Pmd argument of the setRAIMLevels command The external reliability is defined as the influence of a model error of size MDB on the user position It is computed by propagating the MDB for each satellite to the position domain taking the satellite geometry into account The receiver computes a distinct external reliability level XERL for the horizontal and the vertical components referred to as HERL and VERL respectively These values should be compared to the alarm
58. ntion ssssdddf yyt with the 4 character station name designator ssss being the first four characters of the marker name as specified with the setMarkerParameters command For example to set the station name designator to LEUV use setMarkerParameters LEUV lt CR gt RxControl Navigation gt Receiver Setup gt Station Settings Web Interface Configuration Navigation gt Receiver Setup gt Station Settings 2 Use the command setRINEXLogging to specify the file duration fifteen minutes one hour six hours or one day the observation interval and the type of observables to include in the RINEX file For example to generate daily RINEX files with the observation file containing only GPS L1CA data at a 30 s interval use SetRINEXLogging DSK1 Hour24 sec30 GPSL1CA CR RxControl Logging gt Internal RINEX Logging gt RINEX Logging Options Web Interface Logging Internal RINEX Logging gt RINEX Logging Options In this command DSK1 refers to the internal SD memory card 3 The command setDiskFullAction specifies what to do when the SD memory card be comes full For example you could ask the receiver to automatically delete the oldest file to free up disk space To do so use setDiskFullAction DeleteOldest CR RxControl Logging gt Internal Logging Settings Web Interface Logging Internal Logging Settings Instead of logging RINEX files inside the receiver you can also convert a SBF file to RINEX using t
59. o atellite navigation Q9 usb6 serial RxControl File View Communication Navigation Tools Logging Help EB ih r Q M GS 6 E El Y Position Information Position Geodetic WGS84 Velocity Q As h N 50 5201 05297 ox E004 4248 55207 oz 115 516m gu 1 544m 1 058m 2 235m GPS r Y Satellite Status GLONASS Galileo seas moo 0 a aw zn min aun on mn mm neos arm man zn mm n Search Sync 5 1G 2R 2E 0S Track 0 OG OR OE OS PVT 22 11G 8R OE 3S 9 9G OR OE 0S WNc TOW Bias Drift Y Receiver Status Time RxClock 1 539 120 270 1s 497 889us 0 971ppm DOP pL RAM PVT Status Integ Mode EGNOS 5124 System GPS Info LC4FC H Corr Age 2 88s L SEF Status DiffCor ExEvent ExSensor Bxdcszc SSRC1 Figure 1 1 RxControl main window QUICK START The central part of the RxControl main window shows the tracking status of the satellites in the different constellations supported by the receiver Hover mouse over satellite buttons to see Tool Tips with more details The position computed by the receiver is shown in the upper panel of the main window The accuracy estimate for each position component is shown in the middle column Please consult the RxControl on line help under the Help menu for more information Firmware User Manual for
60. o manage the internal SD memory card or to configure internal SBF and or RINEX logging All set and exe user commands described in the Command Line Interface Reference Guide can be accessed from the web interface You can also go to Receiver gt Administration gt Expert Console to manually enter commands and view replies By default the web interface provides unrestricted read and write access to the receiver This can be changed as further explained in section 2 16 of this document 2 1 5 Via FTP FTP access allows to download and delete if you have sufficient access rights log files stored on the internal SD memory card The hostname or fixed IP address is defined as explained in section 2 1 3 For example if your receiver s hostname is ssrc sn1234567 you could type the following URL in your preferred web browser to open a FTP session as anonymous user ftp ssrc sn1234567 The log files are found under the directory ssn SSRC4 By default anonymous FTP users can download and delete files This can be changed as explained in section 2 16 Firmware User Manual for SSRCA 2 5 2 12 Septentrio ENN atellite navigation See also section 2 9 for more details on internal logging 2 1 6 Connection Descriptors To direct output data to a given connection the user has to specify the corresponding connection descriptor Available connection descriptors are COMkx one of the native serial ports USBx one of the vir
61. ocks A clock jump of an integer number of milliseconds is imposed on the receiver clock each time the clock bias exceeds X milliseconds by an absolute value X is set by setClockSyncThreshold This typically results in a saw tooth profile similar to that shown in Figure 3 1 In this example X 0 5ms and each time the clock bias becomes greater than 0 5ms a jump of 1ms is applied 0 0 5 1 1 5 2 2 5 3 3 5 4 Up Time hours tax tanss MS eo RxCIkBias Figure 3 1 Example of the evolution of the receiver time offset with respect to the GNSS time in free running mode When a receiver clock jump occurs all measurements jump simultaneously For example a clock jump of 1ms will cause all the pseudoranges to jump by 0 001s velocity of light 299792 458m The jump is applied on both the pseudoranges and the carrier phase measurements and hence will not be seen on a code minus phase plot The cumulated clock jumps since the last reset of the receiver is reported in the CumC1kJumps field of the MeasEpoch SBF block 3 3 2 Clock Steering In steered mode the receiver time is continuously steered to GNSS time to within a couple of nanosec onds In the example of Figure 3 1 if the user would have enabled clock steering one hour after start up of the receiver the clock bias would have been like in Figure 3 2 below 0 5 T T T T tactongg MS o T RxCIkBias ap I 1 1 ll ll l i 0 0 5 1 1 5 2 2 5 3 3
62. odel and the w tests are of the Generalized Likelihood Ratio Test type The overall model test uses the weighted sum of the squared residuals as test statistic This test statistic is distributed as a x distribution with r degrees of freedom where r is the redundancy number equal to the number of satellites used in the position computation minus 4 The test reads o eT Qye gt x2 r 0 where e g is the overall model test statistic e is the vector of residuals e Qy is the variance covariance matrix of the measurements x2 r 0 is the test threshold yielding a probability a of false alarm The probability of false alarm of the overall model test is selectable by the user with the ModelRelia bility argument of the setRAIMLevels command If the overall model test statistic is lower than the test threshold the test is passed and the integrity is guarantueed under the statistical assumptions specified by the setRAIMLevels command If the overall model test statistic is higher than the threshold the test is rejected In this case the identification step will attempt to identify the measurement responsible for the rejection using the Firmware User Manual for SSRCA 2 5 2 48 Septentrio 3 OPERATION DETAILS atellite navigation t test discussed below After removal of the responsible outlier s the overall model test statistic is recomputed to verify the integrity of the solution without the outlier present Th
63. olatile memory of the receiver select the command applicable to your particular receiver On AsteRx1 receivers autoscr 0x10000000 CR On all other receivers autoscr 0x20000000 CR 7 The previous step can take several seconds When it is completed the receiver outputs the U Boot gt prompt You can now power cycle the receiver or reset it by entering reset lt CR gt 8 The receiver restarts with the new firmware version You can check the firmware version by entering the following command lif Identification CR Firmware User Manual for SSRC4 2 5 2 34 Septentrio i Bown atellite navigation 2 18 Check the Capabilities of your Receiver The capabilities of your receiver are defined by the set of enabled features The capabilities depend on the hardware the current firmware version and the current set of permissions Permissions are further explained in section 2 19 The command getReceiverCapabilities lists the capabilities You can also check them using the web interface go to Receiver Receiver Interface gt Permitted Capabilities or RxControl go to Help gt Receiver Interface and select the Permitted Capabilites tab wm Receiver Interface ES Interface Version j Permitted Capabilities Antennas Main Signals GPSL1CA GPSL2PY GPSL2C GPSLS GLOL1CA GLOL2P GLOL2CA GLOL3 GALL1BC GALESa GALESb GALES GEOL1 Ports DSK1 COM1 COM2 COM3 COM4 USB1 USB2 IP 10 IP11 IP12 IP13 IP14 IP15 IP16
64. omputed from a dataset recorded over a continental area and disseminated via a geostationary satellite The operation of SBAS is documented in the RTCA DO 229 standard SBAS improves over DGPS corrections in that it pro vides system corrections ionosphere corrections and ephemeris long term corrections next to range corrections the fast corrections in the DO 229 terminology The receiver provides an SBAS aided position when it has sufficient satellites with at least fast and long term corrections The corrections are used as long as their applicability has not timed out During the time out interval the receiver applies correction degradation using the information received in message type MT 07 and 10 The receiver will attempt to optimize the selection of the SBAS correction provider based on the number of corrections available For example when it has only 4 corrections from EGNOS but 8 corrections from WAAS the receiver will use the WAAS satellite even though it may be located in the EGNOS service area The PVT propagates the correction variances into a horizontal protection level HPL and a vertical protection level VPL These protection levels indicate the expected user error with an integrity of 1077 Note that these protection levels only refer to the signal in space errors Local effects such as severe multipath are not considered into the HPL VPL computation If the service provider transmits MT27 and MT28 the receiver can det
65. on 2 3 For instance to log all SBF blocks necessary to build RINEX files with the measurements and positions being output at a 10 s interval use setSBFOutput Stream1 DSK1 rinex sec10 CR RxControl Communication gt Output Settings gt SBF Output Web Interface Configuration Communication gt Output Settings gt SBF Output The connection descriptor see section 2 1 6 associated to the memory card is DSK1 3 Start the logging by enabling SBF and NMEA output to the DSK1 connection it is enabled by default setDataInOut DSK1 SBF NMEA CR RxControl Communication gt Input Output Selection Web Interface Configuration Communication gt Input Output Selection 4 Once the logging session is finished stop the logging by invoking setDataInOut DSK1 SBF NMEA CR RxControl Communication gt Input Output Selection Web Interface Configuration Communication 7 Input Output Selection On receivers with a log button you can press the log button to toggle SBF and NMEA logging on and off each time the button is pressed step 3 or 4 above is executed in turn There are different ways to download or delete files from the memory card Using RxControl Select Logging gt Download Internal Files to download files to your com puter and Logging gt Remove Internal File to remove a file from the memory card Firmware User Manual for SSRCA 2 5 2 24 Septentrio AOD atellite navigation
66. re Re ee tous 15 2 3 Output and Log SBF 2 ccc cece eee eee esee eese se sese 16 2 4 Save the Configuration in Non Volatile Memory 2 cce 17 2 5 Configure the Receiver in DGPS RTK Base Mode eeesse 18 25 1 Static Base Station Mode i sco bee RENE Eder enun 18 2 6 Configure the Receiver as a NTRIP Server sssssssssssee m 20 2 7 Configure an IP Server Ports wero ree oo a Lor R EE e eNO de odore dee edes 21 2 8 Configure the SBAS Operation sess eee 22 2 9 Log SBF or NMEA on the SD Memory Card seseees ee eens 24 2 10 Log RINEX Files on the SD Memory Card esse 26 2 11 FIP Push SBF and RINEX files ssssseeeee I memet 27 2 12 Communicate with a Meteo Sensor cece eee ence erence eem 28 2 13 Generate a Pulse Per Second Signal 0 ccc cee cece eee n cece ee ee eee enenneeeeees 29 2 14 Time Tag External Events eroe deer x dennase be setae cease ENEAN ERGS 30 2 15 Monitor th RE Spectrum 2 mai oeste Fe uod oet Ue epebtuts Pe Ret i reb ue utu ia 31 2 16 Manage Users i Lose esi e oi e a a a aide E A A 32 2 17 Upgrade the Recelver i c iori anoe aE a e D EAE 33 2 18 Check the Capabilities of your Receiver cesses 35 2 19 Check or Change the Permission File essssssesee cece ee eee eee eneanee eens 36 2 20 Manage the Processor Load cece cece eee ee cee ee eee meme 37 3 OPERATION DETAILS 38 3
67. rrection Differences GPS Geometric Correction Differences GPS Combined Geometric and Ionospheric Correction Differ ences Helmert Abridged Molodenski Transformation Parameters Molodenski Badekas Transformation Parameters Residuals Ellipsoidal Grid Representation Receiver and Antenna Descriptors GLONASS Ionospheric Correction Differences GLONASS Geometric Correction Differences GLONASS Combined Geometric and Ionospheric Correction Differences APPENDIX A NMEA RTCM AND CMR OVERVIEW Firmware User Manual for SSRC4 2 5 2 52 septentrio APPENDIX A NMEA RTCM AND CMR OVERVIEW si atellite navigation A 1 Proprietary NMEA Sentences PSSN HRP Septentrio Proprietary Sentence Heading Roll Pitch Field Description PSSN HRP Start of sentence hhmmss ss UTC of HRP HoursMinutesSeconds DecimalSeconds XXXXXX Date ddmmyy X X Heading degrees True X X Roll degrees X X Pitch degrees X X Heading standard deviation degrees X X Roll standard deviation degrees X X Pitch standard deviation degrees XX Number of satellites used for attitude computation Mode indicator X 0 No attitude available 5 Estimated attitude dead reckoning X X a Magnetic variation degrees E East W West see also the setMagneticVariance command hh Checksum delimiter and checksum field lt CR gt lt LF gt End of sentence Firmware User Manual for S
68. rresponding RTCM or CMR messages The instructions to set the receiver in base station mode can be found in section 2 5 Appendix A provides a short overview of supported RTCM and CMR messages Note that the receiver supports the CMR and CMR W format as input but not as output It is possible to simultaneously output RTCM messages on one port and CMR data on another port Firmware User Manual for SSRC4 2 5 2 15 Septentrio T atellite navigation 2 3 Output and Log SBF The easiest way to log SBF blocks on your PC is to use the RxControl or RxLogger graphical pro grams which are part of the Rx Tools suite Under RxControl go to the Logging gt RxControl Logging menu to access the logging configuration window Logging on the receiver s internal SD Memory Card is described in section 2 9 of this document In the following example we show how to output SBF blocks using the command line interface The example shows how to configure the receiver to output the MeasEpoch and PVTCartesian SBF blocks at 10 Hz and the GPSNav SBF block at its natural OnChange rate i e when new GPS navigation data is available from a satellite In this example we will assume that these three blocks must be output to the USB2 connection 1 First make sure that the USB2 connection is configured for SBF output this is the default In case this is not so you should invoke setDataInOut USB2 SBF CR RxControl Communication 7 Input Output Se
69. rval The PVT mode as set by the set PVTMode command the user can select between the follow ing modes listed in the order of increasing accuracy standalone SBAS DGPS and RTK The data available to compute ionospheric delays see setIonosphereModel The choice of the dynamics model if the dynamics parameter set by the setReceiverDyna mics command does not correspond to the actual dynamics of the receiver platform the posi tion estimation will be sub optimal Firmware User Manual for SSRCA 2 5 2 41 Septentrio 3 OPERATION DETAILS atellite navigation The a posteriori accuracy estimate of the computed position is reported in the variance covariance matrix which comes in the PosCovCartesian and PosCovGeodetic SBF blocks This accu racy estimate is based on the assumed measurement noise model and may differ from actual errors due to many external factors most of all multipath By default the pseudoranges from the geostationary SBAS satellites are not used in the PVT solution due to the lower quality of the SBAS ephemerides and pseudoranges However for applications where satellite availability is expected to be low it could be beneficial to allow their use in the PVT computation This can be done by using the setSatelliteUsage command 3 4 4 SBAS Positioning SBAS which stands for Space Based Augmentation System enables differential operation over a large area with associated integrity information System errors are c
70. spheric errors are highly correlated within an area of sev eral kilometers This can be exploited by computing the pseudorange errors with respect to one or more known locations and by transmitting these errors to nearby users The receiver can be config ured as a DGPS rover in which it accepts range corrections or as base in which it computes range corrections Local errors at base stations such as multipath will propagate into the rover position Hence a high quality antenna should be used and care should be taken in the choice of the location of the base station s Furthermore any error in the base coordinates will translate in the rover position To work in DGPS rover mode the receiver requires the reception of differential corrections The format of these corrections is standardized in RTCM Note that the receiver takes the 754 parameter transmitted by the GPS satellites into account dur ing the computation of the pseudorange corrections as prescribed in v2 2 and v2 3 of the RTCM standard The RTCM standard version 2 1 is ambiguous in this respect it does neither prescribe nor discourage the use of 7 4 The receiver can be configured in both modes using the command setRTCMv2Compatibility If the received RTCM stream contains corrections from multiple base stations the receiver will com pute a multi base DGPS solution unless the user has forced the usage of a particular base station with the command setDiffCorrUsage Be aware that mu
71. tains whitespaces D Add the Dx obs types for the Doppler in Hz X systems Exclude one or more satellite systems from the obs file systems may be G GPS R Glonass E Galileo S SBAS C Compass J QZSS or any combination thereof For instance xERSC produces a GPS only observation file n type Generate a RINEX navigation file default is observation type may be N for GPS G for GLONASS E for Galileo v3 only H for GEO B for broadcast SBAS MET Generate a RINEX meteo file a antenna Convert data from the specified antenna antenna is 1 2 or 3 The default is 1 corresponding to the main antenna ma Insert a start moving event right after the header if the RINEX file contains kinematic data mf Force inserting a start moving event right after the header S Automatically increase the file sequence character in the output file name This is useful when converting several SBF files collected on the same day and on the same marker For each file to be converted first call sbf2rin to make the O file then call it again with the option nN if needed then again with the option nG if needed and finally with the option nE When the O N Firmware User Manual for SSRCA 2 5 2 57 Septentrio APPENDIX B SBF2RIN UTILITY atellite navigation G and L files are ready from the first SBF file repeat the same sequence for the second SBF file to be converted a
72. ted to 6 seconds type SetRTCMv2Interval RTCM3 10 CR Firmware User Manual for SSRCA 2 5 2 18 Septentrio T atellite navigation RxControl Communication gt Output Settings gt Differential Corrections gt RTCMv2 Web Interface Configuration Communication gt Output Settings gt Differential Corrections gt RTCMv2 6 Use the commands setRTCMv2Formatting setRTCMv3Formatting or setCMRv2 Formatting to specify the base station ID If you are setting up multiple base stations make sure to select a unique ID for each of them For instance SetRTCMv2Formatting 496 CR RxControl Communication gt Output Settings gt Differential Corrections gt RTCMv2 Web Interface Configuration Communication gt Output Settings gt Differential Corrections gt RTCMv2 7 Specify the baud rate of the serial port over which the RTCM or CMR messages have to be sent For instance if the differential correction stream needs to be output on COM2 at 9600 baud use setCOMSettings COM2 baud9600 CR RxControl Communication 7 COM Port Settings Web Interface Configuration Communication gt COM Port Settings 8 Itis recommended to enable code smoothing in order to mitigate propagation of multipath at the base station into the DGPS corrections and RTK data For instance to smooth all pseudoranges with a smoothing length of 900s use setSmoothingInterval all 900 CR RxControl Navigation gt Receiver Operation gt Tracki
73. threshold of your specific application in order to verify if the position solution is adequate for that application Detailed results of the RAIM algorithm are available in the RAIMStatistics and the PVT Residual SBF blocks and in the GBS NMEA message Firmware User Manual for SSRC4 2 5 2 50 APPENDIX A NMEA RTCM AND CMR OVERVIEW Septentrio atellite navigation Appendix A NMEA RTCM and CMR Overview The following tables provide a list of supported NMEA RTCM and CMR messages For a full description of these messages please refer to the respective standard NMEA Sentence Type Short Description ALM AVR DTM GBS GGA GLL GNS GRS GSA GST GSV HDT HRP LLQ PUMRD RBD RBP RBV RMC ROT VTG ZDA GPS Almanac Data Trimble Navigation proprietary PTNL AVR sentence Datum Reference GNSS Satellite Fault Detection GPS Fix Data Geographic Position Latitude Longitude GNSS Fix Data GNSS Range Residuals GNSS DOP and Active Satellites GNSS Pseudorange Error Statistics GNSS Satellites in View Heading True Heading Roll Pitch Septentrio proprietary see section A 1 Leica Local Position and Quality Septentrio proprietary undocumented Rover Base Direction Septentrio proprietary see section A 1 Rover Base Position Septentrio proprietary see section A 1 Rover Base Velocity Septentrio proprietary see section A 1 Recommended Minimum Specific GNSS Data Rate of Turn Course Over Ground and Ground
74. ties to control the receiver and process the GNSS data It is recommended to install all components of the installer USB Driver RxControl Data Link SBF Converter and RxLogger Step 3 Follow the instructions on the screen to install the USB driver After a few seconds the Windows USB driver will automatically create two virtual serial COM ports on your PC If your operating system is Linux only one virtual serial port is created by the default Linux driver Step 4 Start RxControl 1 Open RxControl from the Start menu or by opening the shortcut on your desktop 2 In the Connection Setup dialog from the Serial Connection drop down menu select Create New and click the Next button 3 Select one of the two Septentrio Virtual USB COM ports 4 Enter any connection name and click the Finish button 5 Wait a few seconds for the connection to take place Steps 2 to 4 have to be done only once the next time you will restart RxControl it will connect automatically by using previously entered connection parameters Please always allow a few seconds between connecting the receiver and starting RxControl in order for the USB driver to properly start up To reconfigure your connection select Change Connection from the File menu and repeat steps 2 5 or click New Connection if you see a Connection Error dialog Step 5 After a few seconds you will see the RxControl main window Firmware User Manual for SSRCA 2 5 2 7 1 Septentri
75. tual serial ports built on top of the USB interface DSKx one of the internal disks or SD memory card IP1x one of the TCP IP connections NTRx one of the NTRIP connections IPSx one of the IP Server connections For instance to output the ASCII textual status screen to COMI use setDataInOut COM1 ASCIIDisplay CR Firmware User Manual for SSRCA 2 5 2 13 Septentrio i Howe atellite navigation 2 2 Understand the Output of the Receiver The receiver outputs proprietary and standardized messages Each proprietary message begins with a two character identifier which identifies the message type Proprietary messages First two characters ASCII command replies and command error notification SR ASCII transmissions e g periodic output of the status screen terminated by ST a prompt Two sub types are defined STD ASCII display generated by the receiver STE event notification e g receiver is shutting down Formatted information blocks e g formal command description SNMP binary command replies Septentrio proprietary amp Proprietary binary data SBF se Standardized messages NMEA sentences RTCM v2 x RTCM v3 x CMR v2 0 2 2 1 Proprietary Binary Output SBF The binary messages conform to the Septentrio Binary Format SBF definition The data are arranged in SBF blocks identified by block IDs All the blocks begin with the SBF identifier
76. tyFlag field of the RAIMStatistics SBF block reports an integrity failure if insufficient measurements remain after outlier removal after several D I A steps or if the overall model statistical test fails while no outliers can be identified In the latter case the sum of squared residuals too large error is reported in the Error field of the PVT related SBF blocks The statistical tests assume an a priori model of the measurement error probability distribution As such these tests can have the four classical outcomes in hypothesis testing as shown in the table below the letters A B C and D refer to the samples in Figure 3 4 no outlier outlier present False Alarm Correct outlier detected type I error A D Correct Missed Detection no outlier detected type II error B C The RAIM module makes a correct decision in two cases an outlier present in the data is indeed detected and no outlier is detected when none is present However when no outlier is present and the RAIM module declares an outlier is present a false alarm is triggered When an outlier remains undetected a missed detection occurs The probability computations are based on the assumption that the residuals are distributed as a Nor mal distribution central if there is no outlier and non central if there is one as illustrated in Figure 3 4 Baarda W A Testing Procedure For Use in Geodetic Networks Netherlands Geodetic Commission Publ
77. uccession of SBF blocks possibly inter spersed with other data NMEA sentences for instance The following RINEX file types can be generated Observation file extension yyO GPS navigation file extension yyN GLONASS navigation file extension yyG Galileo navigation file extension yyL SBAS navigation file extension yyH SBAS broadcast data extension yyB Meteo file extension yyM In order to generate a RINEX file the following procedure is recommended Use the setAntennaOffset setMarkerParameters and setObserverParame ters commands to specify the contents of the ReceiverSetup SBF block The contents of this blocks is transferred to the RINEX header The receiver has to be instructed to output the SBF blocks needed for the generation of the RINEX file see section 2 3 The needed SBF blocks depend on the type of RINEX file RINEX file type Mandatory and optional SBF blocks Observation O MeasEpoc PVTCartesian or PVTGeodet ic optional if not available the APPROX POSITION XYZ line will be absent from the RINEX header ReceiverSetup optional if not available a default header will be generated with most fields replaced by unknown Comment optional if available user comments can be inserted GPS Navigation N in the RINEX file GPSNav GPSIon optional needed only if the header should contain the alpha and beta Klobuchar parameters
78. ver the rover which is placed at the location of interest Standardized data format for this measurement exchange are RTCM 2 2 and higher or CMR Thanks to this stan dardization measurements from publicly available reference stations can also be used eliminating the need for a second receiver The distance between the roving receiver and the reference station will be the driving factor to make the choice between a dedicated and a public base station as the baseline length increases the common errors will start to decorrelate Due to the differential nature of phase positioning the unknown ambiguities of phase measurements become integer This is the key to the accuracy of carrier phase positioning if the exact integer value of the ambiguity is known phase measurements can be used as highly accurate satellite ranges If the ambiguity cannot be estimated as an integer the ambiguity will absorb errors that did not completely cancel in the differential application such as multipath 3 4 3 3 Integer Ambiguities RTK fixed Under normal circumstances the receiver will compute the integer ambiguities within several seconds and yield an RTK fixed solution with centimeter level accuracy The less accurate pseudorange mea surements will not be used As long as no cycle slips or loss of lock events occurs the carrier phase position is readily available RTK with fixed ambiguities is also commonly referred to as phase positioning using On The Fly

Download Pdf Manuals

Related Search

Related Contents

Rabbit ® 3000 Microprocessor User`s Manual  サイエンス株式会社 来 歴 記 事 通知番号 年月日氏名 承認 審査 設計  Mise en page 1  TURBO SPEED  SECCION GENERAL - Archivo Nacional del Ecuador  anhang - Hearing Direct  Core Mix-3 USB  PRO FC Installation Users Manual v1.2.docx    

Copyright © All rights reserved. Failed to retrieve file