一种频域RS-LT级联码在短波通信中的应用研究

Application Research of Novel Frequency Domain RS-LT Concatenated Code in HF Communication

针对短波通信中同时存在误码和丢包的特点,提出了一种频域RS码与数字喷泉码串行级联的纠错纠删编码算法,并在FPGA芯片及短波电台终端上予以实现。频域RS码作为外码,LT码作为内码,使RS码和LT码互相促进,同时实现纠删和纠错,这是单独采用两种编码方法都无法达到的。仿真表明RS-LT级联编码可提高LT码译码成功概率。同时短波信道实测结果表明,编码模块的应用可有效提高短波电台正确接收概率。

According to the problem of bit error and frame loosing in HF communication, a serial concatenated forward error and erasure correcting coding method was proposed, which was realized in the FPGA and HF receiving end. The Frequency Domain RS code was employed as outer code, rateless erasure code （LT code） was employed as inter code. The Frequency Domain RS code and LT code promoted each other, realizing error correcting and erasure correcting at the same time. It is hard to be realized using any of RS code or LT transform. Simulation indicates that the RS-LT concatenated encoding method can improve the LT correctly decoding probability. Finally, practical test in HF channel indicates that the RS-LT code can effectively improve the system receiving performance.