?4? GPS?????

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?4? GPS?????

• GPS?????
• GPS?????
• ???????
• ???GPS???(??)

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????????????
???????????????????
??????? ?????????????
?????(????) ???????????
????????60km??1000km???????????????????????X??????
????????????????????
???
?????
?????,?????????????????????????????????????????
???
???(Troposphere)??,????????????????(?)????????????
8km?????????3km??????
?????
?????,???????????????????????????????????????????
?
???????
????????300ns???????????????
???????????????????2???????????????
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???????????

• GDOP(Geometric Dilution Of Position)
• (PDOP)2(TDOP)2
• (VDOP)2(HDOP)2(TDOP)2
• (VDOP)2(NDOP)2(EDOP)2(TDOP)2

DOP?????
DOP?????
??????
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???????????????
5
???????
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????????GPS(DGPS)???
GPS????????????????
???,??????????
?????????????????
?????? ???????
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DGPS???????????
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DGPS?????3??????
???
????? B,L,H
????? b, l, h

• ??????
• ??????
• ?????

????? B0, L0,H0
?? ?B, ?L, ?H
?? ?B, ?L, ?H
????? b-?B, l-?L, h-?H
??? ???
??????????????????????????
???
????
???
???
???
??????
????? b-?B, l-?L, h-?H
???
????? B,L,H
????? b, l, h
B, L, H
???? b-B, l-L, h-H
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DGPS????????
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DGPS?????????????
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??DGPS???
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GPS???????
???(?????) ???????? ?? L1? 1575.42Mhz C/A??? ?
???? 15410.23Mhz P??? (Y???) L2? 1227.6Mh
z P??? ??????? 12010.23Mhz (Y???) GPS?????
???? ???? ?????? ?? C/A??? 1.023Mbps 1023bit
1ms ??? P??? 10.23Mbps ?61012bit7days ????????
?? Y?????? ??????? 50bps ??????300bit6s
????????? ???????1500bit30s ?????????? 5?
?????1??????? ??????? 25???????1???????? ????
????? ? C/A??? Clear and Acquisition???Coarse
and Access?? (S???) Standard Code (S
Code)????? P??? Precision???Protect??
???????
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GPS????????
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GPS?????????

• RTCM
• DGPS?RTK??????
• NMEA
• ?????????????????????????
• RINEX
• GPS???????????????????????????????????????????????
  ????

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NMEA-0183??????

• NMEA???????????(National Marine Electronics
  Association)????????????????????????????????????
• ????NMEA-0183??GPS????????????????????????????????
  ??????NMEA-0183?????????????ASCII?????????????????
  ?
• GPS????????NMEA-0183??????????????????????????????
  ????????????????????????????????????NMEA??????????
  ???
• GPS????????????????????NMEA???????????????????????
  ??????????????NMEA??????????????????????????

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NMEA???????????
GGA - Global Positioning System Fix Data GLL -
Geographic Position, Latitude and Longitude GSA
- GNSS DOP and Active Satellites GSV -
Satellites in View RMC - Recommended Minimum
Specific GNSS Data VTG - Course Over Ground and
Ground Speed ZDA - Time Date
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NMEA????????
??? Pathfinder Pro XR (Trimble)?????????? GPGGA
,050945.00,3504.227794,N,13545.810149,E,1,06,1.4,1
51.00,M,34.53,M,,6AGPGLL,3504.227794,N,13545.81
0149,E,050945.00,A,A68GPVTG,57.1,T,,,000.0,N,00
0.0,K,A73GPGSV,2,1,06,07,36,310,49,11,46,047,48
,20,65,123,46,28,63,258,447FGPGSV,2,2,06,31,16,
109,36,04,16,252,37,,,,,,,,75GPGSA,M,3,07,11,20
,28,31,04,,,,,,,2.2,1.4,1.635GPZDA,050945.09,14
,03,2002,00,0064GPRMC,050945.00,A,3504.227794,N
,13545.810149,E,000.0,57.1,140302,6.5,W,A12 Pathf
inder Pro XR (Trimble)??????DGPS GPGGA,050608.0
0,3504.223942,N,13545.808370,E,2,06,1.4,145.98,M,3
4.53,M,3.0,0694F GPGLL,3504.223942,N,13545.80837
0,E,050608.00,A,D6BGPVTG,322.2,T,,,000.0,N,000.
1,K,D45GPGSV,2,1,06,07,35,309,49,11,47,046,45,2
0,64,126,47,28,63,263,4474GPGSV,2,2,06,31,17,10
7,33,04,15,251,38,,,,,,,,70GPGSA,M,3,07,11,20,2
8,31,04,,,,,,,2.1,1.4,1.737GPZDA,050608.10,14,0
3,2002,00,006AGPRMC,050608.00,A,3504.223942,N,1
3545.808370,E,000.0,322.2,140302,6.5,W,D23
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??????GPS
(a)GARMIN?? ????GPS
(b) NTT???????????????????????????GPS???
(c)???????GPS??????STEL-9300/EP PPS-SM