This dissertation presents you universal serially concatenated trellis-coded modulations (SCTCMs) that perform consistently close to the available mutual information for the periodic erasure channel (PEC), the periodic fading channel (PFC) and the 2 x 2 compound matrix channel. For the PEC and PFC, the universal SCTCMs extend the near-capacity performance of serially concatenated convolutional codes under AWGN to periodically time-varying channels. We use both maximum-likelihood decoding criteria and iterative-decoding criteria to design these universal SCTCMs. Each component of the SCTCM including the constituent codes, constellation, labeling, and interleaver are carefully chosen to achieve universality.; For the space-time channel, by de-multiplexing the symbols across the antennas, universal SCTCMs for the period-2 PFC deliver consistent performance over the eigenvalue skew of the matrix channel. Within the family of channels having the same eigenvalue skew, a time-varying linear transformation (TVLT) is used to mitigate the performance variation over different eigenvectors. Because of their consistent performance over all channels, the proposed codes will have good frame-error-rate (FER) performance over any quasi-static fading distribution.; A graph-conditioning algorithm called the approximate cycle extrinsic message degree (ACE) algorithm is used to construct high-rate (R ≥ 1/2) irregular LDPC codes. For high-rate LDPC codes, due to the large number of degree-2 variable nodes in the optimal degree distribution, it is more difficult to condition the graph. By constraining the number of degree-2 nodes, the ACE algorithm can dramatically lower the error floor with little compromise of the threshold. The same design criteria are suitable for rate-compatible applications using information-nulling.; Another rate-compatible technique uses row-combining, which combines rows of a lower-rate parity-check matrix to form one or more higher-rate parity-check matrices according to predefined combining rules. The resulting LDPC codes are called Constant Blocklength Multiple-Rate (CBMR) LDPC codes. This row-combining approach fits well with an efficient hardware architecture known as the irregular partitioned permutation (IPP) LDPC code. We identified all the constraints that the IPP codes and row-combining placed on the parity-check matrix and designed the row-combined IPP (RC-IPP) codes. The implementation issues of encoding and decoding for RC-IPP codes are exploited. As a result, the RC-IPP codes have FER as good as that of the stand-alone codes at each rate.
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机译：本文向您介绍了通用串行级联网格编码调制（SCTCM），它们的性能始终接近于周期性擦除通道（PEC），周期性衰落通道（PFC）和2 x 2复合矩阵通道的可用互信息。对于PEC和PFC，通用SCTCM将AWGN下的串行级联卷积码的近容量性能扩展到周期性时变信道。我们使用最大似然解码标准和迭代解码标准来设计这些通用SCTCM。 SCTCM的每个组成部分（包括组成代码，星座图，标签和交织器）都经过精心选择，以实现通用性。对于空时信道，通过在天线上对符号进行解复用，周期2 PFC的通用SCTCM在矩阵信道的特征值偏斜上提供了一致的性能。在具有相同特征值偏斜的信道族中，时变线性变换（TVLT）用于减轻不同特征向量上的性能变化。由于它们在所有信道上都具有一致的性能，因此在任何准静态衰落分布上，所提议的代码将具有良好的帧错误率（FER）性能。图条件处理算法称为近似循环外部消息度（ACE）算法，用于构造高速率（R≥1/2）不规则LDPC码。对于高速率LDPC码，由于处于最佳程度分布中的2级变量节点数量众多，因此调整该图更加困难。通过限制2级节点的数量，ACE算法可以在不影响阈值的情况下显着降低错误基底。相同的设计标准适用于使用零信息的速率兼容应用。另一种速率兼容技术使用行合并，该行合并根据预定的合并规则将较低速率的奇偶校验矩阵的行合并以形成一个或多个较高速率的奇偶校验矩阵。所得的LDPC码称为恒定块长多速率（CBMR）LDPC码。这种行组合方法非常适合称为不规则分区置换（IPP）LDPC码的有效硬件体系结构。我们确定了IPP代码和行合并对奇偶校验矩阵施加的所有约束，并设计了行合并IPP（RC-IPP）代码。利用了RC-IPP代码的编码和解码的实现问题。结果，在每个速率下，RC-IPP代码的FER都与独立代码的FER一样好。
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