分析了BICM-ID系统下的几种CE-8-ary (Cross Equalization-8-ary)的映射算法, 并且采用LDPC码代替了传统的卷积码, 从而省去交织器的设计, 降低系统的复杂度和时延。同时从互信息中的信道容量和欧式距离的设计准则出发, 对基于LDPC-BICM-ID系统中的CE-8-ary映射算法进行了理论对比分析。仿真分析表明: 在平均功率相等的受限信道情况下的中高信噪比区, 该CE-8-ary映射算法的信道容量比传统映射算法高出2.73bit/channel, 同时其信噪比增益最大也高达3dB。因而该CE-8-ary映射方案可作为8PSK下LDPC-BICM-ID系统中的一种优越备选方案。

Several CE-8-ary(Cross Equalization-8-ary) mapping algorithms in BICM-ID (Bit-interleaved coded modulation with iterative decoding) systems were analyzed, and the LDPC(Low Density Parity check) code was used to replace the convolutional code so as to omit the design of the interleaver and reduce the complexity and time-delay of the system. At the same time, starting from the design criterion of the channel capacity and Euclidean distance in the mutual information, the CE-8-ary mapping algorithm was systematically and theoretically analyzed. The simulation analysis shows that the channel capacity of the CE-8-ary mapping algorithm is 2.73bit/channel more than that of the traditional mapping algorithm and the maximum of the corresponding signal noise ratio(SNR) gain also is up to 3dB in medium-to-high SNR region under the condition of the equal average power limited channel, so the CE-8-ary mapping scheme can be taken as one excellent alternative scheme in 8PSK LDPC-BICM-ID systems.