双LT码防窃听方案设计

Double LT Code Anti-Eavesdropping Scheme Design

针对传统LT码在窃听信道中窃听者截获效率较高的问题,提出一种双LT码编码的防窃听方案。该方案在传统LT编码的基础上,将第一次LT编码得到的部分码字作为第二次LT编码的信源再次进行LT编码,推迟接收者译码开始时间,致使合法接收者先于窃听者译码概率增加,窃听者无法继续接收LT码并对所接收到的LT符号进行译码,进而使其截获效率降低。实验结果表明,双LT码防窃听方案与其它防窃听LT码相比,仅增加少量译码开销,但是却使窃听者的截获效率大幅度降低。

Aiming at the problem of the high efficiency of interception of eavesdropper in eavesdropping channel with traditional LT code, a double LT code anti-eavesdropping scheme is proposed. Based on the traditional LT code, this scheme uses part of the code words obtained from the first LT code as the source of the second LT code to encode again, delaying the receiver’s decoding start time, increasing the probability of decoding by legitimate receiver before eavesdropper, the eavesdropper cannot continue to receive the LT codes and decode the received LT symbols, thus reducing the interception efficiency. Experimental results show that compared with other anti-eavesdropping LT codes, double LT code anti-eavesdropping scheme only adds a small amount of decoding overhead, but it greatly reduces the interception efficiency of eavesdropper.