基于分离信源信道码的相关信源在有噪广播信道下的可靠和安全传输

摘要

The problem of secure transmission of correlated sources over broadcast channel was studied from the pers-pective of information-theoretic security. Each source is only for its intended receiver, but to be kept secret from the un-intended receiver. Sufficient condition was provided for secure transmission of correlated sources over broadcast channels from separate source-channel coding perspective. If the mutual information was chosen as common information, optimal compression and partial perfect secrecy were both achieved for two correlated sources. Sufficient and necessary condi-tions were provided for two special cases:a broadcast channel with degraded source sets and a more capable broadcast channel, and thus it could be seen that the separate source-channel code is optimal.%从信息论的角度对相关信源在离散无记忆广播信道下可靠和安全传输的问题进行研究。2个信源经过有噪信道分别到达各自指定的目的节点并被无损恢复，同时还要保证信源信息对于非指定的目的节点要有一定的保密性。采用信源信道分离的随机码策略，得到相关信源在一般广播信道下能够可靠和安全传输的充分条件。当2个信源的公共信息为二者的互信息时，可获得最佳压缩传输效率，并且能够做到信源信息传输的部分绝对保密。当广播信道采用退化信源集或满足more capable广播信道性质时，得到了可靠和安全传输的充分必要条件，此时分离信源信道码为最优码。