利用校验方程平均符合度的DVB_RCS协议中DB-CTC识别算法

Recognition Algorithm for DB-CTC in DVB_RCS Protocol Using Average Conformity of Parity-check Equation

信道编码参数分析是对编码参数进行逆向分析,在协作通信、智能通信和信息截获等领域具有重要作用。针对DVB_RCS协议中双二进制卷积Turbo码(DB-CTC)码长和删除模式的识别,提出一种基于校验方程平均符合度的匹配识别算法。文章首先给出了校验方程平均符合度的概念及计算方法,并推导出各删除模式下信息序列与校验序列之间所满足的校验方程;然后利用需依据码长和删除模式对接收序列进行分路,以及正确分路得到的序列可使得相应删除模式下的校验方程平均符合度取到最大值这两个事实,进行码长和删除模式的识别。仿真结果表明,所提算法能够快速有效地识别低信噪比条件下不同码率的码长和删除模式。

Channel coding parameter analysis meant reversely analyzing and estimating the coding parameters, and played an important role in applications like cooperative communication, intelligent communication and information interception. This paper presented an identification algorithm for the code lengths and puncturing patterns of the double binary convolu- tional turbo codes （DB-CTC） in DVB_RCS protocol, based on the average conformity of parity-check equation. Firstly, the concept and calculation method of the average conformity of parity-check equation were given, and the parity-check equa- tions between the information sequences and the check sequences of each puncturing pattern were also derived. Then, the DB-CTC parameters were identified, using the two truths that the separation of received sequences was performed according to these parameters and the correctly separated sequences could maximize the average conformity of parity-check equation. Simulation results show that the proposed algorithm can effectively identify the true code length and puncturing pattern under low signal-to-noise ratios for different code rates.