详解NMEA数据格式
NMEA数据如下： $GPGGA,121252.000,3937.3032,N,11611.6046,E,1,05,2.0,45.9,M,-5.7,M,,0000*77 $GPRMC,121252.000,A,3958.3032,N,11629.6046,E,15.15,359.95,070306,,,A*54 $GPVTG,359.95,T,,M,15.15,N,28.0,K,A*04 $GPGGA,121253.000,3937.3090,N,11611.6057,E,1,06,1.2,44.6,M,-5.7,M,,0000*72 $GPGSA,A,3,14,15,05,22,18,26,,,,,,,2.1,1.2,1.7*3D $GPGSV,3,1,10,18,84,067,23,09,67,067,27,22,49,312,28,15,47,231,30*70 $GPGSV,3,2,10,21,32,199,23,14,25,272,24,05,21,140,32,26,14,070,20*7E $GPGSV,3,3,10,29,07,074,,30,07,163,28*7D $GPGGA,032648.00,2307.595860,N,11321.993373,E,1,09,0.9,30.7,M,-5.2,M,,*4C
$PSAT,HPR,032714.00,74.19,-23.16,,N*1F
说明：NMEA0183格式以“$”开始，常用语句有GPGGA，GPVTG，GPZDA等
1、 GPS DOP and Active Satellites（GSA）当前卫星信息
$GPGSA,<1>,<2>,<3>,<3>,,,,,<3>,<3>,<3>,<4>,<5>,<6>,<7>
<1>模式 ：M = 手动， A = 自动。 <2>定位型式 1 = 未定位， 2 = 二维定位， 3 = 三维定位。 <3>PRN 数字：01 至 32 表天空使用中的卫星编号，最多可接收12颗卫星信息。 <4> PDOP位置精度因子（0.5~99.9） <5> HDOP水平精度因子（0.5~99.9） <6> VDOP垂直精度因子（0.5~99.9） <7> Checksum.(检查位).
2、 GPS Satellites in View（GSV）可见卫星信息 $GPGSV, <1>,<2>,<3>,<4>,<5>,<6>,<7>,?<4>,<5>,<6>,<7>,<8>
<1> GSV语句的总数 <2> 本句GSV的编号 <3> 可见卫星的总数，00 至 12。 <4> 卫星编号， 01 至 32。 <5>卫星仰角， 00 至 90 度。 <6>卫星方位角， 000 至 359 度。实际值。 <7>讯号噪声比（C/No）， 00 至 99 dB；无表未接收到讯号。 <8>Checksum.(检查位).
第<4>,<5>,<6>,<7>项个别卫星会重复出现，每行最多有四颗卫星。其余卫星信息会于次一行出现，若未使用，这些字段会空白。
3、Global Positioning System Fix Data（GGA）GPS定位信息
$GPGGA,<1>,<2>,<3>,<4>,<5>,<6>,<7>,<8>,<9>,M,<10>,M,<11>,<12>*hh
<1> UTC时间，hhmmss（时分秒）格式 <2> 纬度ddmm.mmmm（度分）格式（前面的0也将被传输） <3> 纬度半球N（北半球）或S（南半球） <4> 经度dddmm.mmmm（度分）格式（前面的0也将被传输） <5> 经度半球E（东经）或W（西经） <6> GPS状态：0=未定位，1=非差分定位，2=差分定位，6=正在估算 <7> 正在使用解算位置的卫星数量（00~12）（前面的0也将被传输） <8> HDOP水平精度因子（0.5~99.9） <9> 海拔高度（-9999.9~99999.9） <10> 地球椭球面相对大地水准面的高度 <11> 差分时间（从最近一次接收到差分信号开始的秒数，如果不是差分定位将为空） <12> 差分站ID号0000~1023（前面的0也将被传输，如果不是差分定位将为空）
4、Recommended Minimum Specific GPS/TRANSIT Data（RMC）推荐定位信息
$GPRMC,<1>,<2>,<3>,<4>,<5>,<6>,<7>,<8>,<9>,<10>,<11>,<12>*hh
<1> UTC时间，hhmmss（时分秒）格式 <2> 定位状态，A=有效定位，V=无效定位 <3> 纬度ddmm.mmmm（度分）格式（前面的0也将被传输） <4> 纬度半球N（北半球）或S（南半球） <5> 经度dddmm.mmmm（度分）格式（前面的0也将被传输） <6> 经度半球E（东经）或W（西经） <7> 地面速率（000.0~999.9节，前面的0也将被传输） <8> 地面航向（000.0~359.9度，以真北为参考基准，前面的0也将被传输） <9> UTC日期，ddmmyy（日月年）格式 <10> 磁偏角（000.0~180.0度，前面的0也将被传输） <11> 磁偏角方向，E（东）或W（西） <12> 模式指示（仅NMEA0183 3.00版本输出，A=自主定位，D=差分，E=估算，N=数据无效）
5、 Track Made Good and Ground Speed（VTG）地面速度信息 $GPVTG,<1>,T,<2>,M,<3>,N,<4>,K,<5>*hh <1> 以真北为参考基准的地面航向（000~359度，前面的0也将被传输） <2> 以磁北为参考基准的地面航向（000~359度，前面的0也将被传输） <3> 地面速率（000.0~999.9节，前面的0也将被传输） <4> 地面速率（0000.0~1851.8公里/小时，前面的0也将被传输） <5> 模式指示（仅NMEA0183 3.00版本输出，A=自主定位，D=差分，E=估算，N=数据无效）
以下是英文手册摘要
-------------------------------------------------------------------------------------- $GPGST GPS Pseudorange Noise Statistics
Example: $GPGST,024603.00,3.2,6.6,4.7,47.3,5.8,5.6,22.0*58
Field Example Comments Sentence ID $GPGST UTC Time 024603.00 UTC time of associated GGA fix RMS deviation 3.2 Total RMS standard deviation of ranges inputs to the navigation solution Semi-major deviation 6.6 Standard deviation (meters) of semi-major axis of error ellipse Semi-minor deviation 4.7 Standard deviation (meters) of semi-minor axis of error ellipse Semi-major orientation 47.3 Orientation of semi-major axis of error ellipse (true north degrees) Latitude error deviation 5.8 Standard deviation (meters) of latitude error Longitude error deviation 5.6 Standard deviation (meters) of longitude error Altitude error deviation 22.0 Standard deviation (meters) of latitude error Checksum *58
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$GPGSV GPS Satellites in view
eg. $GPGSV,3,1,11,03,03,111,00,04,15,270,00,06,01,010,00,13,06,292,00*74 $GPGSV,3,2,11,14,25,170,00,16,57,208,39,18,67,296,40,19,40,246,00*74 $GPGSV,3,3,11,22,42,067,42,24,14,311,43,27,05,244,00,,,,*4D
$GPGSV,1,1,13,02,02,213,,03,-3,000,,11,00,121,,14,13,172,05*62
1 = Total number of messages of this type in this cycle 2 = Message number 3 = Total number of SVs in view 4 = SV PRN number 5 = Elevation in degrees, 90 maximum 6 = Azimuth, degrees from true north, 000 to 359 7 = SNR, 00-99 dB (null when not tracking) 8-11 = Information about second SV, same as field 4-7 12-15= Information about third SV, same as field 4-7 16-19= Information about fourth SV, same as field 4-7
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$GPHDT Heading, True.
Actual vessel heading in degrees Ture produced by any device or system producing true heading.
$--HDT,x.x,T x.x = Heading, degrees True
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$GPMSK Control for a Beacon Receiver
$GPMSK,318.0,A,100,M,2*45
where: 318.0 Frequency to use A Frequency mode, A=auto, M=manual 100 Beacon bit rate M Bitrate, A=auto, M=manual 2 frequency for MSS message status (null for no status) *45 checksum
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$GPMSS Beacon Receiver Status
Example 1: $GPMSS,55,27,318.0,100,*66
where: 55 signal strength in dB 27 signal to noise ratio in dB 318.0 Beacon Frequency in KHz 100 Beacon bitrate in bps *66 checksum Example 2: $GPMSS,0.0,0.0,0.0,25,2*6D
Field Example Comments Sentence ID $GPMSS Signal strength 0.0 Signal strength (dB 1uV) SNR 0.0 Signal to noise ratio (dB) Frequency 0.0 Beacon frequency (kHz) Data rate 25 Beacon data rate (BPS) Unknown field 2 Unknown field sent by GPS receiver used for test Checksum *6D
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$GPR00 List of waypoint IDs in currently active route
eg1. $GPR00,EGLL,EGLM,EGTB,EGUB,EGTK,MBOT,EGTB,,,,,,,*58 eg2. $GPR00,MINST,CHATN,CHAT1,CHATW,CHATM,CHATE,003,004,005,006,007,,,*05
List of waypoints. This alternates with $GPWPL cycle which itself cycles waypoints.
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$GPRMA Recommended minimum specific Loran-C data
eg. $GPRMA,A,lll,N,lll,W,x,y,ss.s,ccc,vv.v,W*hh A = Data status lll = Latitude N = N/S lll = longitude S = W/E x = not used y = not used ss.s = Speed over ground in knots ccc = Course over ground vv.v = Variation W = Direction of variation E/W hh = Checksum
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$GPRMB Recommended minimum navigation information (sent by nav. receiver when a destination waypoint is active)
eg1. $GPRMB,A,0.66,L,003,004,4917.24,N,12309.57,W,001.3,052.5,000.5,V*0B
A Data status A = OK, V = warning 0.66,L Cross-track error (nautical miles, 9.9 max.), steer Left to correct (or R = right) 003 Origin waypoint ID 004 Destination waypoint ID 4917.24,N Destination waypoint latitude 49 deg. 17.24 min. N 12309.57,W Destination waypoint longitude 123 deg. 09.57 min. W 001.3 Range to destination, nautical miles 052.5 True bearing to destination 000.5 Velocity towards destination, knots V Arrival alarm A = arrived, V = not arrived *0B mandatory checksum
eg2. $GPRMB,A,4.08,L,EGLL,EGLM,5130.02,N,00046.34,W,004.6,213.9,122.9,A*3D 1 2 3 4 5 6 7 8 9 10 11 12 13 1 A validity 2 4.08 off track 3 L Steer Left (L/R) 4 EGLL last waypoint 5 EGLM next waypoint 6 5130.02 Latitude of Next waypoint 7 N North/South 8 00046.34 Longitude of next waypoint 9 W East/West 10 004.6 Range 11 213.9 bearing to waypt. 12 122.9 closing velocity 13 A validity 14 *3D checksum
eg3. $GPRMB,A,x.x,a,c--c,d--d,llll.ll,e,yyyyy.yy,f,g.g,h.h,i.i,j*kk 1 = Data Status (V=navigation receiver warning) 2 = Crosstrack error in nautical miles 3 = Direction to steer (L or R) to correct error 4 = Origin waypoint ID# 5 = Destination waypoint ID# 6 = Destination waypoint latitude 7 = N or S 8 = Destination waypoint longitude 9 = E or W 10 = Range to destination in nautical miles 11 = Bearing to destination, degrees True 12 = Destination closing velocity in knots 13 = Arrival status; (A=entered or perpendicular passed) 14 = Checksum
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$GPRMC Recommended minimum specific GPS/Transit data
eg1. $GPRMC,081836,A,3751.65,S,14507.36,E,000.0,360.0,130998,011.3,E*62 eg2. $GPRMC,225446,A,4916.45,N,12311.12,W,000.5,054.7,191194,020.3,E*68
225446 Time of fix 22:54:46 UTC A Navigation receiver warning A = Valid position, V = Warning 4916.45,N Latitude 49 deg. 16.45 min. North 12311.12,W Longitude 123 deg. 11.12 min. West 000.5 Speed over ground, Knots 054.7 Course Made Good, degrees true 191194 UTC Date of fix, 19 November 1994 020.3,E Magnetic variation, 20.3 deg. East *68 mandatory checksum
eg3. $GPRMC,220516,A,5133.82,N,00042.24,W,173.8,231.8,130694,004.2,W*70 1 2 3 4 5 6 7 8 9 10 11 12
1 220516 Time Stamp 2 A validity - A-ok, V-invalid 3 5133.82 current Latitude 4 N North/South 5 00042.24 current Longitude 6 W East/West 7 173.8 Speed in knots 8 231.8 True course 9 130694 Date Stamp 10 004.2 Variation 11 W East/West 12 *70 checksum
eg4. for NMEA 0183 version 3.00 active the Mode indicator field is added $GPRMC,hhmmss.ss,A,llll.ll,a,yyyyy.yy,a,x.x,x.x,ddmmyy,x.x,a,m*hh Field # 1 = UTC time of fix 2 = Data status (A=Valid position, V=navigation receiver warning) 3 = Latitude of fix 4 = N or S of longitude 5 = Longitude of fix 6 = E or W of longitude 7 = Speed over ground in knots 8 = Track made good in degrees True 9 = UTC date of fix 10 = Magnetic variation degrees (Easterly var. subtracts from true course) 11 = E or W of magnetic variation 12 = Mode indicator, (A=Autonomous, D=Differential, E=Estimated, N=Data not valid) 13 = Checksum
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$GPRTE Routes
eg. $GPRTE,2,1,c,0,PBRCPK,PBRTO,PTELGR,PPLAND,PYAMBU,PPFAIR,PWARRN,PMORTL,PLISMR*73 $GPRTE,2,2,c,0,PCRESY,GRYRIE,GCORIO,GWERR,GWESTG,7FED*34 1 2 3 4 5 .. Number of sentences in sequence Sentence number ''''c'''' = Current active route, ''''w'''' = waypoint list starts with destination waypoint Name or number of the active route onwards, Names of waypoints in Route
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$GPTRF Transit Fix Data
Time, date, position, and information related to a TRANSIT Fix.
$--TRF,hhmmss.ss,xxxxxx,llll.ll,a,yyyyy.yy,a,x.x,x.x,x.x,x.x,xxx hhmmss.ss = UTC of position fix xxxxxx = Date: dd/mm/yy llll.ll,a = Latitude of position fix, N/S yyyyy.yy,a = Longitude of position fix, E/W x.x = Elevation angle x.x = Number of iterations x.x = Number of Doppler intervals x.x = Update distance, nautical miles x.x = Satellite ID