rtcm 10403.3

（1）使用两台ubx接收机进行单天24h静态测试，rtcm格式，GPS+BDS双频数据，数据采样率1s； （2）01表示base端数据，02表示rover端数据； （3）进行RTK解算前，请使用rtkconv将rtcm格式转为rinex格式，近似时间请选择20220703零点，可以转换为obs和nav； （4）使用该数据进行RTK调试，优化代码前，即使用官方版本，模糊度固定率和定位精度较差；使用优化代码自测后，单频RTK模糊度固定率可以达到99.9%，定位精度在2cm左右；使用双频RTK模糊度固定率可以达到99.6%，定位精度在2cm左右；

BNC软件是由BKG开发的一款用于实时同步接收、解码及转换的GNSS数据流管理软件。采用BNC软件进行实时精密单点定位时，其主要功能是接收来自Ntrip Caster的由IGS提供的精密轨道和钟差的改正系数，以及实时广播星历数据流，并对其进行解码，同时通过TCP／IP、UDP通讯接收来自测站接收机的观测值，通过这些数据流完成精密单点定位。

RTCM官网文档，详解了RTCM数据的构成，对差分GPS的开发很有帮助。

u-blox M8 说明文档 V15 包括 NMEA/UBX/RTCM 三种协议 u-blox M8 Receiver Description Including Protocol Specification V15

This standard has been developed by RTCM Special Committee 104 as a more efficient alternative to Version 2 in various documents entitled "RTCM Recommended Standards for Differential Navstar GPS Service, Version 2.x”. Service providers and vendors represented on the SC-104 Committee requested the development of a new standard that would be more efficient, easy to use, and more easily adaptable to new situations. The main complaint was that the Version 2 parity scheme, which uses words with 24 bits of data followed by 6 bits of parity, was wasteful of bandwidth. Another complaint was that the parity was not independent from word to word. Still another was that even with so many bits devoted to parity, the actual integrity of the message was not as high as it should be. Plus, 30-bit words are awkward to handle. This standard, Version 3, is intended to correct these weaknesses.

官方售价340的协议RTCM3.3， RTCM STANDARD 10403.3 DIFFERENTIAL GNSS (GLOBAL NAVIGATION SATELLITE SYSTEMS) SERVICES – VERSION 3 DEVELOPED BY RTCM SPECIAL COMMITTEE NO. 104 OCTOBER 7, 2016 COPYRIGHT2016 RTCM Radio Technical Commission for Maritime Services

RTCM 3解码器/编码器 直至RTCM 3.3修订1（c10403.3）的所有RTCM 3消息类型的解码器/编码器。 正在安装 npm install -S @gnss/rtcm 基本用法 解码 let buffer : Buffer = ... ; // Raw bytes of message to be decoded let message : RtcmMessage ; // Decoded message let length : number ; // Length of decoded message in bytes [ message , length ] = RtcmTransport . decode ( buffer ) ; // ... buffer = buffer . slice ( length ) ; // Move to next message