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MN002000A © 2004 Navman NZ Ltd. All rights reserved. Proprietary information and specifications subject to change without notice.

Appendix B: References

This appendix provides a list of documents that 

may help a user of Navman’s GPS receivers to 

learn more about the way the GPS can be used. 

Not all of these documents have been referred to 

in the text of this document.

1. Global Position System Standard Positioning 

Service Signal Specification, United States 

Department of Defense.

2. Standard For Interfacing Marine Electronic 

Devices, NMEA 0183, National Marine Electronics 

Association.

3. RTCM Recommended Standards for Differential 

NAVSTAR GPS Service, Radio Technical 

Commission for Maritime Services.

4. Principle of Operation of NAVSTAR and 

System Characteristics, Milliken and Zoller, Global 

Positioning System, Vol 1, 1980, pp. 3-14.

5. Department of Defense World Geodetic System 

1984, DMA TR 8350.2.

6. Internet web site for the National Geophysical 

Data Centre (NGDC): “http://julius.ngdc.noaa.

gov/seq/potfld/geomag.html” 

APPENDIX C: NAVSTAR GPS 

operation

NAVSTAR GPS is a space-based satellite 

radio navigation system developed by the U.S. 

Department of Defense (DoD). GPS receivers 

provide land, marine, and airborne users with 

continuous 3D position, velocity, and time data. 

This information is available free of direct charge 

to an unlimited number of users. The system 

operates under all weather conditions, 24 hours 

a day, anywhere on Earth. There are three major 

segments: 

• space segment
• control segment
• user segment

The space segment

This segment consists of a nominal constellation 

of 24 operational satellites (including 3 spares). 

These satellites have been placed in 6 orbital 

planes (see Figure C-1) about 20 200 km 

(10 900 miles) above the Earth’s surface. The 

satellites are in circular orbits with a 12-hour orbital 

period and inclination angle of 55 degrees. This 

orientation normally provides a GPS user with a 

Figure C-1 NAVSTAR GPS operational satellite 

constellation 

minimum of 5 satellites in view from any point on 

Earth at any time. 

Each satellite continuously broadcasts an RF 

signal at a centre frequency of 1575.42 MHz 

(Ll band). This signal is modulated by a 10.23 MHz 

clock rate precise ranging signal and by a 

1.023 MHz clock rate coarse acquisition (C/A) 

code ranging signal. Each of these two binary 

signals has been formed by a precision code 

(p-code) or a C/A code which is modulo-2 added 

to 50 bps navigation data. 

This navigation data, which is computed and 

controlled by the GPS Control Segment, includes 

the satellite’s time, its clock correction and 

ephemeris parameters, almanacs, and health 

status for all GPS satellites. From this information, 

the user computes the satellite’s precise position 

and clock offset. Currently, the DoD encrypts the 

P-code ranging signal and thus denies access 

to the Precise Positioning Service (PPS) by 

unauthorised users. The Standard Positioning 

Service (SPS) uses the C/A code ranging signal 

and is intended for general public use. 

The control segment

This segment consists of a master control station, 

located in Colorado Springs, and a number of 

monitor stations at various locations around 

the world. Each monitor station tracks all the 

GPS satellites in view and passes the signal 

measurement data back to the master control 

station, where computations are performed to 

determine precise satellite ephemeris and satellite 

clock errors. The master control station generates 

the upload of user navigation data for each 

satellite. This data is subsequently re-broadcast by 

the satellite as part of its navigation data message. 

The user segment

This segment is the collection of all GPS receivers 

and their application support equipment such 

Содержание 12

Страница 1: ...oning DR Development kit TU10 D007 352 Jupiter Pico standard Development kit TU10 D007 361 Jupiter Pico timing Development kit TU10 D007 363 Related documents Jupiter T Product brief LA010039 Data she...

Страница 2: ...Message 1007 channel measurement 19 3 5 1 6 Message 1009 reduced ECEF position status output 20 3 5 1 7 Message 1011 receiver ID 21 3 5 1 8 Message 1012 user settings output 22 3 5 1 9 Message 1100 bu...

Страница 3: ...est command message IBIT 55 3 6 2 2 Navman proprietary log control essage ILOG 55 3 6 2 3 Navman proprietary receiver initialisation message INIT 56 3 6 2 4 Navman proprietary protocol message IPRO 57...

Страница 4: ...HPE validity criterion 67 4 6 4 5 Maximum EVPE validity criterion 67 4 6 5 Mean Sea Level MSL 67 4 6 6 Magnetic variation 67 4 7 Support functions 67 4 7 1 Serial communication interfaces 67 4 7 1 1 T...

Страница 5: ...ve Availability designed for passive or active antennas for lowest system cost adaptive threshold based signal detection for improved reception of weak signals maximum navigation accuracy achievable w...

Страница 6: ...irst Fix TTFF under all start up conditions The best TTFF performance is normally achieved when time of day and current position estimates are provided to the receiver However the exible Jupiter signa...

Страница 7: ...receiver with an application processor that drives peripheral devices such as a display and keyboard The interface between the application s processor and the Jupiter receiver is through the serial da...

Страница 8: ...are incorporated in the message description tables the most convenient speci cation of memory layout in application implementation is likely to be a structure de nition If the item is a xed point quan...

Страница 9: ...ehaviour With this approach the user can con gure requests only to be NAKed alerting the user when a problem arises without incurring the overhead necessary to continuously process ACKs The lower six...

Страница 10: ...ds thereafter When the trigger eld is set to on update the speci ed message will be output only when the data is updated e g when satellite almanac is collected 3 3 Binary message data The data portio...

Страница 11: ...s between the starting delimiter and the terminating CR and LF Since the number of data elds can vary from sentence to sentence it is important that the listener or application software locate elds by...

Страница 12: ...d for hours minutes and seconds to maintain xed length the decimal point and associated decimal fraction are optional if full resolution is not required De ned eld Some elds are speci ed to contain pr...

Страница 13: ...y criteria 1217 Built in test results 1100 User entered altitude Input 1219 UTC time mark pulse output 1108 Application platform control 1220 Frequency standard parameters in use 1110 Nav con guration...

Страница 14: ...he poles should use the ECEF position status output message See Table 3 5 Message ID 1000 Rate variable defaults to 1 Hz Message length 55 words Word No Name Type Units Range 1 4 Message header 5 Head...

Страница 15: ...d for output The T10 range is approximately 71 weeks Note 2 The sequence number is a count that indicates whether the data in a particular binary message has been updated or changed since the last mes...

Страница 16: ...et time is an internal 10 millisecond T10 count since power on initialisation enabled the processor interrupts It is not used to derive GPS time but only serves to provide a sequence of events knowled...

Страница 17: ...wer on initialisation enabled the processor interrupts It is not used to derive GPS time but only serves to provide a sequence of events knowledge The set time or T10 count references the receiver s i...

Страница 18: ...tellite bad j 11 Corrections stale Bit 1 received stale corrections j 12 lODE mismatch Bit 1 lODE mismatch j 13 j 15 Reserved 25 Data checksum Note 1 Set time is an internal 10 millisecond T10 count s...

Страница 19: ...tion enabled the processor interrupts It is not used to derive GPS time but only serves to provide a sequence of events knowledge The set time or T10 count references the receiver s internal time at w...

Страница 20: ...Note 1 Set time is an internal 10 millisecond T10 count since power on initialisation enabled the processor interrupts The set time indicated is at the time the message is submitted to the output que...

Страница 21: ...references the receiver s internal time at which the message was created for output The T10 range is approximately 71 weeks Note 2 The sequence number is a count that indicates whether the data in a p...

Страница 22: ...Number of satellites in track required UI 0 to 12 17 18 Minimum expected horizontal error UDI m 0 to 1000 10 2 19 20 Minimum expected vertical error UDI m 0 to 1000 10 2 21 Application platform UI 0...

Страница 23: ...ed to derive GPS time but only serves to provide a sequence of events knowledge The set time or T10 count references the receiver s internal time at which the message was created for output The T10 ra...

Страница 24: ...Set time is an internal 10 millisecond T10 count since power on initialisation enabled the processor interrupts It is not used to derive GPS time but only serves to provide a sequence of events knowle...

Страница 25: ...ce of events knowledge The set time or T10 count references the receiver s internal time at which the message was created for output The T10 range is approximately 71 weeks Note 2 The sequence number...

Страница 26: ...me or T10 count references the receiver s internal time at which the message was created for output The T10 range is approximately 71 weeks Note 2 The sequence number is a count that indicates whether...

Страница 27: ...ts 10 Port 1 stop bits Bit 0 1 1 2 11 Port 1 parity Bit 0 no parity 1 odd parity 2 even parity 12 Port 1 bps rate Note 3 Bit 0 custom 1 300 2 600 3 1200 4 2400 5 4800 6 9600 7 19200 8 38400 9 57600 10...

Страница 28: ...Data checksum Note 1 Set time is an internal 10 millisecond T10 count since power on initialisation enabled the processor interrupts It is not used to derive GPS time but only serves to provide a sequ...

Страница 29: ...ction 1 position 15 user entered altitude 2 UTC iono 16 DGPS control 3 frequency standard cubic parameters 17 host port protocol selection 4 host port communication con guration 18 auxiliary port prot...

Страница 30: ...ps where the LSB PRN 1 and the MSB PRN 32 Note 4 The failure and status words are bit maps with values as follows 0 status 16 DGPS control 1 position 17 host port protocol selection 2 UTC lono 18 auxi...

Страница 31: ...receiver s internal time at which the message was created for output The T10 range is approximately 71 weeks Note 2 The sequence number is a count that indicates whether the data in a particular binar...

Страница 32: ...iting for a command Table 3 21 Message 1180 ash boot status Message ID 1190 Rate variable Message length 13 words Word No Name Type Units Range 1 4 Message header 5 Header checksum 6 7 Set time Note 1...

Страница 33: ...17 18 Latitude DI rad 0 to 2 10 9 19 20 Longitude DI rad 0 to 10 9 21 22 Altitude DI m 0 to 50000 10 2 23 24 Ground speed UI m s 0 to 1000 10 2 25 Course UI rad 0 to 2 10 3 26 Climb rate i m s 300 10...

Страница 34: ...age length 8 words Word No Name Type Units Range 1 4 Message header 5 Header checksum 6 Sequence number Note 1 I 0 to 32767 7 Datum ID Note 2 UI 0 to 188 and 300 to 304 8 Data checksum Note 1 The sequ...

Страница 35: ...included 7 15 Satellite PRN 16 Bit 1 included 8 0 Satellite PRN 17 Bit 1 included 8 15 Satellite PRN 32 Bit 1 included 9 0 Non volatile storage select Bit 1 store in non volatile memory 9 1 9 15 Reser...

Страница 36: ...sage 1216 cold start control 3 5 2 6 Message 1214 DGPS control This message allows the user to control the behavior of the receiver s differential capability Storage of this message s parameters requi...

Страница 37: ...uired Note 3 Bit 1 required 7 4 GPS only solution required Note 4 Bit 1 required 7 5 7 15 Reserved 8 Minimum number of satellites used UI 0 to 12 9 10 Maximum expected horizontal position error UDI m...

Страница 38: ...nsor that is supplying data in real time the OEM must ensure that bits 7 2 and 7 3 are set to zero so the attitude value will not be stored continuously in memory RAM or EEPROM Table 3 31 Message 1219...

Страница 39: ...4 Message header 5 Header checksum 6 Sequence number Note 1 I 0 to 32767 7 Platform UI 0 default 1 static 2 pedestrian 3 marine lakes 4 marine sea level 5 land auto 6 air 8 Data checksum Note 1 The se...

Страница 40: ...te as required maximum rate approximately 0 1 Hz Message length 8 words Word No Name Type Units Range 1 4 Message header 5 Header checksum 6 Sequence number Note 1 I 0 to 32767 7 Reserved 8 Data check...

Страница 41: ...indicates whether the data in a particular binary message has been updated or changed since the last message input Note 2 1 invalidate all RAM address space before restart Note 3 1 invalidate all dat...

Страница 42: ...inary message has been updated or changed since the last message input Note 2 Unique identi cation of each update This allows a different set of data to be in use while newer data are only stored to E...

Страница 43: ...ode the RF power may be switched off to reduce power consumption The digital circuitry may be gated off and the processor idled when not needed This eld gives the measurement engine permission to turn...

Страница 44: ...ost scale Note 2 UI 0 to 7 14 Port 2 character width Bit 0 7 bits 1 8 bits 15 Port 2 stop bits bit 0 1 1 2 16 Port 2 parity Bit 0 no parity 1 odd parity 2 even parity 17 Port 2 bps rate Bit 0 custom 1...

Страница 45: ...o 85 0 01 8 9 Oscillator frequency error I ppm 0 to 51 0 01 10 Data checksum Note 1 The sequence number is a count that indicates whether the data in a particular binary message has been updated or ch...

Страница 46: ...ssage input Note 3 Raw demodulated data must conform to the 6 of 8 format described in the RTCM SC 1 04 standard The data must also be packed into one or more 16 bit words and should be ordered chrono...

Страница 47: ...8 1 8 15 Reserved 9 Offset error estimate Note 4 I ppm 0 to 51 0 002 10 Aging rate estimate Note 5 I ppm yr 0 to 5 0 0002 11 last rate update week Note 6 I weeks 0 to 32767 1 12 267 Frequency standar...

Страница 48: ...ary Jupiter channel status ZCH Input Message Name Message lD Navman proprietary built in test command IBIT Navman proprietary log control message ILOG Navman proprietary receiver initialisation INIT N...

Страница 49: ...eparation metres m M 13 DGPS_AGE Age of differential GPS data Note 5 x x 7 14 STA_ID Differential reference station ID 0000 to 1023 Note 6 xxxx 0000 CKSUM Checksum hh 41 CR LF Sentence terminator CR L...

Страница 50: ...ote 2 Xx 60 6 AZ Azimuth in true degrees 000 to 359 Note 2 Xxx 216 7 SNR SNR C No 00 to 99 dB null when not tracking Xx 50 8 11 2nd satellite PRN number elevation azimuth SNR Note 1 xx xx xxx xx 12 15...

Страница 51: ...d CKSUM Checksum hh 40 CR LF Sentence terminator CR LF Note 1 The options list is a bit encoded con guration word represented as a four digit hexadecimal number Bit 0 minimises ROM usage bit 1 minimis...

Страница 52: ...ion degrees x x 13 8 11 MAG_REF Magnetic variation E east W west Note 2 a E CKSUM Checksum hh 55 CR LF Sentence terminator CR LF Note 1 The position status ag will be set to V data invalid until the r...

Страница 53: ...M Magnetic course indicator m M 5 SPD_N Speed over the ground knots x x 0 784 6 N Nautical speed indicator N knots n N 7 SPD_K Speed km x x 1 452 8 K Speed indicator K km hr k K CKSUM Checksum hh 4F C...

Страница 54: ...llite PRN number and status indication xx hh 23 24 Channel 12 satellite PRN number and status indication xx hh CKSUM Checksum hh 37 CR LF Sentence terminator Note 1 Channel number xx is implied by pos...

Страница 55: ...lF Sentence terminator CR lF Note 1 NMEA message pre x P proprietary message indicator RWI Navman Systems Inc mnemonic ILOG log control message ID Note 2 A special form of this eld disables all output...

Страница 56: ...mnemonic INIT Initialisation message ID Note 2 this function is enabled by default Each of the elds 1 through 14 may be null to indicate that the previous setting for the data item should be left unc...

Страница 57: ...ote 1 The identi er of the device from which data is being requested refer to paragraph 5 4 4 of this chapter must be GP GPS device for the Jupiter receiver to recognise the message otherwise the mess...

Страница 58: ...the required data is not available from SRAM see section 4 7 for more information about the EEPROM 4 1 4 Read Only Memory ROM On board ROM is only used as a data source if SRAM and EEPROM are unavail...

Страница 59: ...s 4 3 3 Satellite selection Jupiter GPS receivers provide two con guration features related to satellite selection elevation mask angle and candidate satellite speci cation Satellite elevation mask an...

Страница 60: ...metacommands that can override or complement an existing set of con guration data Note These straps are only read once at initialisation time so a power cycle or hardware or software reset must be exe...

Страница 61: ...le satellite lists are generated by events that could cause a change in satellite list membership or could indicate a signi cant change in a satellite position relative to the antenna These events inc...

Страница 62: ...iver s ability to acquire and track satellites under these conditions Conversely this scheme sets a higher threshold when strong signals are received This method results in more reliable acquisition o...

Страница 63: ...63 MN002000A 2004 Navman NZ Ltd All rights reserved Proprietary information and speci cations subject to change without notice Figure 4 1 Jupiter search process...

Страница 64: ...ether with their identi cation codes are listed in Appendix E of this document All of the pre de ned datums are taken from the US Government document Department of Defense World Geodetic System 1984 4...

Страница 65: ...gating and a velocity has been established by the Kalman lter it will be used to propagate the state forward in the absence of further measurements for a limited time period until the estimated errors...

Страница 66: ...sers should leave it enabled One reason for disabling it would be to compare the solution with a point solution from another receiver or a solution calculated off line Ground track smoothing can be di...

Страница 67: ...ipsoid and is referred to as geodetic altitude Altitude referenced to the geoid usually referred to as altitude MSL can be computed as the geodetic altitude minus the geoid separation 4 6 6 Magnetic v...

Страница 68: ...2 4 7 3 RTC services The RTC services provide for the storage of time date data maintained while the system is in an idle state As long as external power is provided to the RTC device it will keep the...

Страница 69: ...l RTCM messages not all messages are necessary for DGPS operation The Data Sheet for each of the Jupiter GPS receivers shows which of the messages de ned in the RTCM standard are used by the receiver...

Страница 70: ...es for these words are received within a DGPS control message that also contains a reset then the new values will be in effect after the reset However after a DGPS reset all other DGPS parameters will...

Страница 71: ...e 1100 indicates the results of a time rollover test of the RTC A failed status indicates that the RTC test failed and that the RTC chip may be defective PORT 1 host port and PORT 2 aux port error and...

Страница 72: ...command is received from the application processor The 3D calculated altitude used in this way is called an auto hold altitude B Boolean Baud See bps BIT Built In Test Block I satellite satellites des...

Страница 73: ...the effect of the satellite geometry on the position and time accuracy of the GPS receiver solution The lower the value of the GDOP parameter the less the error in the position solution Related indic...

Страница 74: ...solution using the measurements from all GPS satellites it can track instead of the four necessary for a three dimensional position solution P Code Precision Code a spread spectrum direct sequence cod...

Страница 75: ...one pulse per second lPPS output synchronised to UTC when the receiver is in its Navigation Mode TOW Time Of Week see GPS time TTFF Time To First Fix The actual time required by a GPS receiver to achi...

Страница 76: ...face The satellites are in circular orbits with a 12 hour orbital period and inclination angle of 55 degrees This orientation normally provides a GPS user with a Figure C 1 NAVSTAR GPS operational sat...

Страница 77: ...a pseudorange Changes in each of these pseudo ranges over a short period of time are also measured and processed by the receiver These measurements referred to as delta pseudoranges are used to comput...

Страница 78: ...e of the receiver s position velocity and time Four other DOP components indicate how the geometry speci cally affects errors in horizontal position HDOP vertical position VDOP position PDOP and time...

Страница 79: ...m but they could be more than 30 m under SA Satellite clock errors differences between the satellite clock time and that predicted by the satellite data The oscillator that times the satellite signal...

Страница 80: ...transparent to the GPS receiver whether the data is transmitted continuously or in bursts or whether protocol overhead is added For example each message or multiple messages or any fraction of a messa...

Страница 81: ...rily a function of the quality and latency of the corrections used 6 What is the difference between the two models for position determination used in GPS WGS 84 and Earth Centred Earth Fixed ECEF ECEF...

Страница 82: ...78249 145000 293 465000 7 Everest 1830 6377276 345000 300 801700 8 Everest 1948 6377304 063000 300 801700 9 Fischer 1960 6378166 000000 298 300000 10 Modi ed Fischer 1960 6378155 000000 298 300000 11...

Страница 83: ...iland 6 134 105 295 19 Arc 1950 Zaire 6 169 19 278 20 Arc 1950 Zambia 6 147 74 283 21 Arc 1950 Zimbabwe 6 142 96 293 22 Arc 1960 MEAN FOR Kenya Tanzania 6 160 6 302 23 Ascension Island 1958 Ascension...

Страница 84: ...raq Israel Jordan Lebanon Kuwait Saudi Arabia Syria 15 103 106 141 52 European 1950 Cyprus 15 104 101 140 53 European 1950 Egypt 15 130 117 151 54 European 1950 England Channel Islands Ireland Scotlan...

Страница 85: ...ia Eritrea 4 639 405 60 93 Merchich Morocco 6 31 146 47 94 Midway Astro 1961 Midway Islands 15 912 58 1227 95 Minna Cameroon 6 81 84 115 96 Minna Nigeria 6 92 93 122 97 Montserrat Island Astro 1958 Mo...

Страница 86: ...FOR Hawaii Kauai Maui Oahu 5 61 285 181 126 Old Hawaiian Hawaii 5 89 279 183 127 Old Hawaiian Kauai 5 45 290 172 128 Old Hawaiian Maui 5 65 290 190 129 Old Hawaiian Oahu 5 58 283 182 130 Oman Oman 6...

Страница 87: ...tina Bolivia Brazil Chile Colombia Ecuador Guyana Paraguay Peru Trinidad Tobago Venezuela 17 57 1 41 163 South American 1969 Argentina 17 62 1 37 164 South American 1969 Bolivia 17 61 2 48 165 South A...

Страница 88: ...21 Carthage 70 NAD 27 Mexico 22 Chatham 1971 71 North America 1983 23 Chua Astro 72 Observatorio 1966 24 Corrogo Alegre 73 Old Egyptian 1960 25 Djakarta Batavia 74 Old Hawaiian 26 DOS 1968 75 Oman 27...

Страница 89: ...r Typical Speci cation for RG 316 I Electrical Characteristics Nominal impedance 50 Nominal inductance 0 065 micro h ft Nominal capacitance conductor to shield 29 0 pf ft Nominal velocity of propagati...

Страница 90: ...RELATING TO FITNESS FOR A PARTICULAR PURPOSE CONSEQUENTIAL OR INCIDENTAL DAMAGES MERCHANTABILITY OR INFRINGEMENT OF ANY PAT ENT COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT NAVMAN FURTHER DOES NOT...

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