GPS探空系统通信模块的DSP设计

Communication Module Design for GPS Radiosonde System Based on DSP

GPS高空气象探测技术比常规雷达探空技术性能更优。由于频段(国际电联规定的400MHz气象频段)的限制,其信道重用、邻频干扰和其它干扰情况极为严重,令GPS探空系统通信信道的质量极差。为此,采用RSCC级联编码方式进行信道编码。Matlab仿真结果表明,在400MHz载波频率、2400bit/s、5dB信噪比的条件下,传输误码率降低到10-3,数据接收率能够满足气象探空的要求。最后给出了采用TMS320VC5402的通信模块硬件实现的编、译码核心部分。

Meteorological sounding using GPS technology performs better than conventional radar sounding. Channel muse, adjacent channel interfemnce and other interference are very serious as the limits of band of 400 MHz regulated by ITU, which leads to the poor quality of communication channel. Therefore, RSCC cas- cade code is used for channel coding. Matlab simulation results show that, in the condition of 400 MHz carrier frequency,2400 baud rate,SdB SNR, the BER reduces to 10-3 ,and the data receiving rate is able to meet the requirements of meteorological sounding. Finally, DSP TMS320VC5402 is adopted in hardware to realize the core part of encoding and decoding of the communicating module.