该文档详细介绍了基于M-285 GPS模块组的功能，以及如何解析标准协议NEMA0813相应的GPS数据。同时详细讲解了IPPS授时原理和如何精度。是系统运行更加准确。
在T-285 Warm start 33 seconds Hot start I second Reacquisition <1 second accura Position:3 m/2.5 m with dgps Ⅴ elocity:0.1m/s Time: ImS rms Maximum altitude < 18.000 meter Maximum vclocity 515 meter/second Maximum acceleration <4G Update rate 5 HZ DGPS WAAS EGNOS. MSAS RTCM IO Pins 6-pin connector Dimensions 25.4x254x7mm Power Suppl oly 33~5Vdc±5% Backup voltage 1.2Vdc±10% Power Consumption Acquisition: 52mA Tracking. 27mA Power down:14mA humidity range 5%to 95%o non-condensing Operation temperature 30℃1085℃ Storage Temperature 40C to 125C Page 3 of 28 在T-285 Block Diagram 点 YY Fite RI 32-Channel Correlators Optional StARTS ⅹ0Rⅹ0 RTO flasl SPI ⅹ1RX1 Power TX2 RX2 Battery GND TLXTΔL Page 4 of 28 在T-285 Module pin assignment Pin6 卫iL Pin name Description ⅤCC5V 3.3-55Vdc power input 2 TXA Scrial data output port a 3 RXA Serial Data input port A 4 RXB Serial data input port b 5 GND Power ground 6 Default: TIMEMARK Default: IPPS Time mark output or Option: RESET Option: Reset Input(Active Low) Page 5 of 28 在T-285 Application circuit YY CY Frequency: 1575.42+2 MHZ Axial ratio: 3 dB Typical output Impedance: 50Q2 Polarization: rhCP Amplifier gain: 20-26dB Typical Output VSWR: 2.0 Max Noise Figure: 2.0 dB Max Page 6 of 28 在T-285 Dimensions 15C0 5.4C±03 PIN 25,40±0.30 100±1 Page 7 of 28 在T-285 Preamble TalkerID PktType DataField CHKI CHK2 CR LF Page 8 of 28 在T-285 Page 9 of 28 在T-285 Page 10 of 28