Sequential Decoding of Trellis Codes

网格编码调制（TCM）已被证明是一种非常有效的带宽高效通信调制技术。使用这种技术可以在给定信道上获得更高的数据速率。通常，这种调制格式的解码器是维特比解码器，它对从接收信号中提取的软判决数据执行最大似然序列估计。维特比解码器的复杂性随着编码约束长度呈指数增长，从而限制了实际操作的适度编码增益和解码速度。顺序解码技术提供了一种独立于代码约束长度的性能，从而允许使用更长的代码来获得更大的编码增益。本项目涉及：1；选择合适的顺序解码算法，以使用栅格编码调制。2. 时序解码的性能评估，同时使用分析和仿真技术，当使用网格编码调制。3. 构造用于顺序解码的良好的长约束长度网格码。

Trellis-coded modulation (TCM) has proved to be very effective as a modulation technique for bandwidth-efficient communication. Higher data rates over a given channel are obtainable using this technique. Typically, the decoders for this modulation format are Viterbi decoders, which perform a maximum-likelihood sequence estimation upon soft-decision data extracted from the received signal. The complexity of the Viterbi decoders grows exponentially with code constraint length, thus limiting practical operation to moderate coding gains and decoding speeds. The sequential decoding technique gives a performance which is independent of code constraint length thereby permitting the use of longer codes to obtain a greater coding gain. This project is concerned with: 1. The selection of an appropriate sequential decoding algorithm for use with trellis-coed modulation. 2. The performance evaluation of sequential decoding, using both analytical and simulation techniques when used with trellis-coded modulation. 3. The construction of good long-constraint-length trellis codes for use with sequential decoding.