SCCPM的非相干接收机设计与仿真

串行级联连续相位调制(SCCPM)的相干迭代接收机需要知道载波相位信息和精确的信道信息,然而这些信息在低信噪比下难以获得.针对此问题,研究了SCCPM非相干接收机,通过连续观察多个码元计算得到非相干解调的CPM信道转移概率,利用修正的CPM软输入软输出(SISO)算法实现迭代的解调和解码.仿真了码元速率为1/2外卷积码,通过随机交织器级联调制指数h=1/2的二进制 CPM组成的SCCPM系统.仿真结果表明,在AWGN信道中,所提出的非相干接收机比相干接收机的性能在误比特率为10-3时大约仅下降0.4dB.与SCCPM相干迭代接收机相比,此非相干接收机有着相似的迭代接收机结构,实现较容易.

Design and Simulation of Non-coherent Receiver for Serially Concatenated Continuous Phase Modulation

The coherent receiver of serially concatenated continuous phase modulation(SCCPM) requires carrier phase recovery and perfect channel information,but such information is difficult to obtain at low Eb/N0.For this reason,a non-coherent receiver for SCCPM is studied in this paper.By using a multiple-symbol observation,the non-coherent CPM demodulator calculates the channel transition probability,and the modified soft-in soft-output(SISO) algorithm is used by the CPMSISO module to iteratively demodulate and decode.The paper simulates the SCCPM scheme which consists of a convolutional code encoder with a rate of 1/2 through a random interleaver and binary CPM with modulation index h=1/2.Simulation results show that the proposed non-coherent receiver for SCCPM has an approximately performance degradation of only 0.4dB at the bit error rate of 10-3 from the corresponding coherent receiver in a AWGN channel.Compared with the coherent iterative receiver,the proposed non-coherent receiver has a similar iterative receiver structure and can be realized easily.