基于数据冗余的BDS长报文传输机制改进算法∗

摘要

Beidou Navigation Satellite System ( BDS ) only supports byte⁃limited short message transmitting. For long message transmitting, BDS adopts a sub⁃packeting and multiple retransmission method to improve the success rate of packet transmission, which may cause data delay and network congestion. In this paper, a data redundancy based packet transmis⁃sion mechanism is proposed. In this mechanism, the date packets are processed using XOR⁃based algorithm to obtain redun⁃dant packets. This mechanism features in simple and efficient coding and encoding. Through Matlab simulation, it is proved that the single transmission⁃reception success rate based on redundancy mechanism is 15% higher than that without redun⁃dancy, and the twice retransmission method helps to improve the sucess rate of multiple packet reception.%北斗卫星导航系统（ Beidou Satellite Navigation System，BDS）只能传输字节受限的短报文，对于长报文需要通过分包和多次重传改善报文传输的成功率，这样会造成系统平台数据发送延误和网络拥塞。提出一种基于数据冗余的数据分包传输机制，该传输机制以数据包为处理对象，采用异或运算得到冗余包，编码简单，编码解码速度快。通过Matlab仿真，证明基于冗余编码机制比无冗余编码单次发送机制的数据接收成功率高15％以上，两次发送对多包的数据接收成功率有较大提高。