衰落信道中等增益分集用于调制分类

针对在Rayleigh和Rician慢衰落信道下的QAM信号的调制分类问题,提出一种新的基于等增益分集的调制分类算法。给出等增益分集用于调制分类的模型,对合并器输出信号的归一化四阶累积量进行估计作为分类特征,并推导了用于判决的等增益合并器输出信号的四阶累积量理论值。计算复杂度仅为N阶(N为样本个数),数值仿真实验结果以及与已有方法的比较证明了理论分析的正确性和算法的实用性。

Equal Gain Combining for Modulation Classification in Fading Channel

To study the modulation classification problem for M-ary quadrature amplitude modulation(QAM) signals traveled slowly over Rayleigh and Rician fading channels,a new algorithm based on equal gain combining is proposed in the paper.The equal gain diversity model for modulation classification is given in which equal gain combining is used to combine the signals received by multiple antennas.The normalized fourth-order cumulents of the signal at the output of the combiner are estimated,which can be used as modulation classification features.The theoretical values of the normalized fourth-order cumulents of the signal at the output of the combiner for various constellations are derived as the classification criterions.The computational complexity of the developed algorithm is order N,where N is the number of the complex base-band data samples.The theoretical arguments and the practicability of the algorithm are verified via extensive simulations and comparisons with the existing approaches.