高效网格编码调制TC-MQAM的构造

The Construction of High-Efficiency TCM with MQAM

将网格编码和多值正交幅度调制（MQAM）相结合，利用于集旋转来分割十字型32QAM，构造了两种最优8状态4／5TC－32QAM高效网格编码。同时还给出了在加性白高斯噪声信道下以平方欧氏距离为度量准则的最大似然译码。最后对几种不同调制方式下接收机的误码率进行了数值模拟。

In this paper trellis - coding combined with multi - value quadrature amplitude modulation (MQAM) is formed by partitioning of the signal set rotationally. Two optimum trellis-coded modulations (TCM ) of 8 states with bandwidth and power efficiency are construct ed. One of them has the characteristic of 180° phase rotation invariant. The performances of the TCM and the corresponding uncoded systems in additive white Gaussian noise (AWGN)channel are studied in detail by numerical simulations as well as theoretital analysis. Finally,the performance improvements of the coded systems over the uncoded systems are given.