IS-GPS-200F (811524), страница 23
Текст из файла (страница 23)
Thetimeframe is defined by the CS.30.3.3 Message Content. Each message starts with an 8-bit preamble - 10001011, followed by a 6-bit PRN numberof the transmitting SV, a 6-bit message type ID with a range of 0 (000000) to 63 (111111), and the 17-bit messagetime of week (TOW) count. When the value of the message TOW count is multiplied by 6, it represents SV time inseconds at the start of the next 6-second message.An “alert” flag, when raised (bit 38 = “1”), indicates to the user that the signal URA components may be worse thanindicated in the associated message types and that he shall use at his own risk.
For each default message (MessageType 0), bits 39 through 276 shall be alternating ones and zeros and the message shall contain a proper CRC parityblock.139IS-GPS-200F21 Sep 2011Figure 30-1.Message Type 10 - Ephemeris 1140IS-GPS-200F21 Sep 20111915PRN6BITS8 BITS6BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS3850392183MESSAGETOW COUNT*toeΩ0-ni0-n17 BITS11 BITS33 BITS18 MSBsMESSAGE TYPE IDPREAMBLE"ALERT" FLAG - 1 BITMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS101133116148164180i0-n•∆Ωi0-n - DOTcis-ncic-ncrs-n15 LSBs17 BITS15 BITS16 BITS16 BITS21 MSBsMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS201204228270249crc-ncus-ncuc-n24 BITS21 BITS21 BITScrs-n - 3 LSBs277CRC7 BITS24 BITSRESERVED* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-2.Message Type 11 - Ephemeris 2141IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS5BITS"ALERT" FLAG - 1 BITtocaf0-n11 BITS26 BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS1011281189872URANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139141154167180193af1-naf2-nTGDISCL1C/AISCL2CISCL5I5ISCL5Q5α017 LSBs10 BITS13 BITS13 BITS13 BITS13 BITS13 BITS8 BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS201209217225233241257249α1α2α3β0β1β28 BITs8 BITS8 BITS8 BITS8 BITS8 BITSβ3WNOP8 BITS 8 BITS265277RESERVEDCRC12 BITS24 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-3.
Message Type 30 - Clock, IONO & Group Delay142IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS5BITS"ALERT" FLAG - 1 BITtocaf0-n11 BITS26 BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS1011281189872URANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139141149180af1-naf2-nWNa-ntoaReduced AlmanacPacket 1Reduced AlmanacPacket 217 LSBs10 BITS13 BITS8 BITS31 BITS21 MSBsDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS20110 LSBs211MSB FIRST273 277242Reduced AlmanacPacket 3Reduced AlmanacPacket 431 BITS31 BITSReduced Almanac Packet 2CRC4BITS24 BITSRESERVED* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-4.
Message Type 31 - Clock & Reduced Almanac143IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS5BITS"ALERT" FLAG - 1 BITtocaf0-n11 BITS26 BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS1011441281189872URANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139165180af1-naf2-ntEOPPM-X•PM-XPM-Y17 LSBs10 BITS16 BITS21 BITS15 BITS21 BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS201266247216•PM-Y∆UT1•∆UT115 BITS31 BITS19 BITS277RESERVEDCRC11 BITS24 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-5.Message Type 32 - Clock & EOP144IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS5BITS"ALERT" FLAG - 1 BITtocaf0-n11 BITS26 BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS1011281189872URANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139144157164172188af1-naf2-nA0-nA1-nA2-n∆tLStotWNot17 LSBs10 BITS16 BITS13 BITS7 BITS8 BITS16 BITS13 BITSDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDSWNLSF13 BITS277226214 218201∆tLSF4BITS 8 BITSDNMSB FIRSTRESERVEDCRC51 BITS24 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-6.Message Type 33 - Clock & UTC145IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS"ALERT" FLAG - 1 BIT101128118af1-naf2-n17 LSBs10 BITS5BITS9872tocaf0-n11 BITS26 BITSURANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139DIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS150139151top-D11 BITSMSB FIRST185tODCDCEDC11 BITS34 BITS16 MSBsDC DATA TYPE – 1 BITDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDSMSB FIRST277201EDCCRC76 LSBs24 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGECDC = Clock Differential CorrectionEDC = Ephemeris Differential CorrectionFigure 30-7.Message Type 34 - Clock & Differential Correction146IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS5BITS"ALERT" FLAG - 1 BITtocaf0-n11 BITS26 BITSDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS1011281189872URANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139144157 160MSB FIRST189176af1-naf2-ntGGTOWNGGTOA0GGTOA1GGTO17 LSBs10 BITS16 BITS13 BITS16 BITS13 BITSA2GGTO7 BITS 5 BITSRESERVEDGNSS ID – 3 BITSDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS196MSB FIRST277201RESERVEDCRC76 BITS24 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-8.Message Type 35 - Clock & GGTO147IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS5BITS"ALERT" FLAG - 1 BITtocaf0-n11 BITS26 BITSDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS1019872URANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139MSB FIRST128118af1-naf2-n17 LSBs10 BITSTEXT MESSAGE (18 8-BIT CHAR)73 MSBsDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDSMSB FIRST272201276277TEXT MESSAGE (18 8-BIT CHAR)CRC4BITS71 LSBsTEXT PAGE24 BITSRESERVED – 1 BIT* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-9.Message Type 36 - Clock & Text148IS-GPS-200F21 Sep 2011192115PRN6BITS8 BITS6BITSMESSAGETOW COUNT*top17 BITS11 BITS5BITS"ALERT" FLAG - 1 BITtocaf0-n11 BITS26 BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS1011281189872URANED2 INDEX - 3 BITSURANED1 INDEX - 3 BITSaf1-n – 3 MSBsURANED INDEXMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS385055 58 6139149141af1-naf2-nWNa-n17 LSBs10 BITS13 BITStoa155 158180δiePRNa8 BITS 6 BITS16911 BITS11 BITS191•ΩA11 BITS10 MSBsL1 HEALTH – 1 BITL2 HEALTH – 1 BITL5 HEALTH – 1 BITMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS201240224208256277267AΩ0ωM0af0af1CRC7 LSBs16 BITS16 BITS16 BITS11 BITS10 BITS24 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-10.Message Type 37 - Clock & Midi Almanac149IS-GPS-200F21 Sep 20111915PR N8 BITS6BITS6BITS21M ESSAG ETOW CO UNT*13 BITS17 BITS91t oaReduced Alm anacPacket 18 BITS31 BITSW N a-n10 MSBsR educed Alm anac Packet 2M ESSAG E TYPE IDPREA MBLEM SB FIRSTDIREC TIO N O F DATA FLOW FR O M SV100 BITS4 SECO ND S38605239"ALERT" FLAG - 1 BITDIREC TIO N O F DATA FLOW FR O M SV100 BITS4 SECO ND S122101Reduced Alm anacPacket 221 LSBs153184R educed Alm anacPacket 4Reduced Alm anacPacket 3215Reduced Alm anacPacket 531 BITS31 BITSDIREC TIO N O F DATA FLOW FR O M SV100 BITS4 SECO ND S201M SB FIRST17 MSBsM SB FIRST277246R educed Alm anacPacket 5Reduced Alm anacPacket 6Reduced Alm anacPacket 7C RC14 LSBs31 BITS31 BITS24 BITS* MESSAG E TOW CO UNT = 17 MSB OF AC TUAL TOW CO U NT AT STAR T O F NE XT 12-SECO N D MESSAG EFigure 30-11.Message Type 12 - Reduced Almanac150IS-GPS-200F21 Sep 2011121159MESSAGETOW COUNT*PRN8 BITS6BITS6BITStop-D11 BITS17 BITS9697CDCtODMESSAGE TYPE IDPREAMBLEMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS613850396211 BITS34 BITSDC DATA TYPE – 1 BITDC DATA TYPE – 1 BITCDC - 4 MSBs"ALERT" FLAG - 1 BITMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS131166132167101CDCCDCCDC30 LSBs34 BITS34 BITSDC DATA TYPE – 1 BITDC DATA TYPE – 1 BITDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS236237201202CDCCDC34 BITS34 BITSMSB FIRST2712776BITSCRC24 BITSDC DATA TYPE – 1 BITDC DATA TYPE – 1 BITRESERVED* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGECDC = Clock Differential CorrectionFigure 30-12.Message Type 13 - Clock Differential Correction151IS-GPS-200F21 Sep 2011121159PRN8 BITS6BITSDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS38615039626BITSMESSAGETOW COUNT*17 BITStop-D11 BITSMESSAGE TYPE IDPREAMBLEEDCtOD11 BITSMSB FIRST39 MSBsDC DATA TYPE – 1 BIT"ALERT" FLAG - 1 BITDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS154155101MSB FIRSTEDCEDC53 LSBs46 MSBsDC DATA TYPE – 1 BITDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS247201MSB FIRST277EDCRESERVEDCRC46 LSBs30 BITS24 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEEDC = Ephemeris Differential CorrectionFigure 30-13.Message Type 14 - Ephemeris Differential Correction152IS-GPS-200F21 Sep 20111159PRN8 BITS6BITS6BITSMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS383921MESSAGETOW COUNT*TEXT MESSAGE (29 8-BIT CHAR)62 MSBs17 BITSMESSAGE TYPE IDPREAMBLE"ALERT" FLAG - 1 BITMSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS101TEXT MESSAGE (29 8-BIT CHAR)BITS 63-162MSB FIRSTDIRECTION OF DATA FLOW FROM SV100 BITS4 SECONDS271201275277TEXT MESSAGE (29 8-BIT CHAR)CRC4BITS70 LSBsTEXT PAGE24 BITSRESERVED – 2 BITS* MESSAGE TOW COUNT = 17 MSB OF ACTUAL TOW COUNT AT START OF NEXT 12-SECOND MESSAGEFigure 30-14.Message Type 15 – Text153IS-GPS-200F21 Sep 201130.3.3.1 Message Type 10 and 11 Ephemeris and Health Parameters.30.3.3.1.1 Message Type 10 and 11 Ephemeris and Health Parameter Content.
![](https://s.studizba.com/z.php?f=/templates/si/i/noavatar.png&w=100&h=100&t=1"){kind=avatar}
