Multi-h CPM信号的减少状态多符号差分非相干检测

Reduced-state Multi-symbol Differential Non-coherent Detector for Multi-h CPM

针对多指数连续相位调制(Multi-h CPM)载波恢复困难且实现复杂度高的难题,提出了一种适用于Multi-h CPM信号的减少状态多符号差分非相干检测算法。该算法利用多符号差分信息进行分支度量计算的同时引入参考相位信号,实现了具有残留载波频偏校正的非相干序列检测,并且结合逐幸存处理技术,利用幸存路径上的假设判决信息减少了网格状态数。通过计算和搜索接收信号所有可能调制指数序列所对应的分支度量信息实现了调制指数的估计与同步。计算机仿真结果表明,与相干最大似然序列检测相比,该算法能够以较小的性能损失获得其实现复杂度的降低,而且当存在残留载波频偏时,该算法的检测性能也较为稳健。

To solve the difficulty and complexity of carrier recovery problem of Multi-h CPM, an algorithm of reduced-state multi-symbol differential non-coherent detector for Multi-h CPM is proposed. Non-coherent sequence detection of residual carrier frequency offset amendment is realized through the calculation of multi-symbol differential information branch metric and the inductive reference phase signal. Using per-survivor processing technology, the number of states is reduced by surviving path tentative decision information. Modulation index estimation and synchronization is realized by calculation and searching branch metrics according to possible modulation index sequence. Simulation analysis shows that, compared with coherent maximum likeli- hood sequence detection, the proposed algorithm can get small performance loss complexity and its implementation complexity is reduced, and when ex- isting residual carrier frequency offset, its detection performance is also robust.