该文提出低密度奇偶校验(LDPC)码自适应调制编码正交频分复用(AMC-OFDM)系统,并详述了该系统的原理。针对传统AMC系统中调制编码方案(MCS)的选择准则对性能提升有限的问题,提出可用于该AMC系统的两种MCS选择准则,根据接收到的所有单元信号的后验SNR确定相应自适应块采用的MCS。文章分析了这两种准则的吞吐量性能。仿真结果表明,把这两种准则应用于LDPC编码的AMC-OFDM系统中,能够带来比传统选择方法更高的吞吐量。
A Low Density Parity Check (LDPC) coded Adaptive Modulation and Coding-Orthogonal Frequency Division Multiplexing (AMC-OFDM) system is proposed, and its theory is given in detail, In order to solve the problem that the traditional Modulation and Coding Scheme (MCS) selecting rule improves the performance limitedly, two MCS selecting rules are proposed for the AMC system, in which MCS for an adaptive block is determined by the posteriori Signal-to-Noise-Ratio (SNR) of units in the block. Throughput performance is analyzed for the two rules. Simulation results show that they can bring to much higher throughput than the traditional method when applied in LDPC coded AMC-OFDM system,