SCCPM的非相干接收机设计与仿真

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

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。

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.