but for the same reason, it have n't the same diversity feature as space-time block code, as well as it have n't the same error correction capability as convolutional code or trellis code modulation 由于空时格码兼顾了分集和信道编码,导致其分集特性不如空时分组码,纠错能力不如卷积码和格形编码调制。
in the third part, a new adaptive trellis coded modulation ( atcm ) solution was presented . we analysis the best coding scheme in different channel modes, different snr and different demodulation solution 仿真结果表明,在解调观测长度相同的情况下,其性能和多码元差分解调方式大致相同,但大大简化了接收机结构。
for its error correction performance extremely close to the shannon limit, from the beginning, turbo codes attracts the eyes of enormous professionals and researchers . in turn, it is called the greatest contribution after ungerboeck's trellis coded modulation ( tcm ) 因为它具有极其逼近香农极限的纠错性能,从一开始turbo码便吸引了通信领域无数专家学者的关注与研究,进而被誉为继ungerboeck提出格状编码调制(tcm)以来,信道编码领域最伟大的贡献。