通用PSK和QAM解调接收机

在航天和卫星通信领域的CCSDS,DVB等多个标准中,都采用PSK和QAM调制方式,此外PSK和QAM调制也在其他商用标准中予以采用,因而通用PSK和QAM解调接收机的研究是十分必要的.本文基于通用的正交解调结构,根据模块共用和参数通用的设计原则,提出一种数据率可变的通用PSK和QAM解调接收机.接收机PSK解调的载波恢复采用Costas环,QAM解调的载波恢复采用减星座的Costas环,而PSK和QAM解调的定时恢复采用Gardner算法.解调性能的仿真结果表明:与理论值相比,BPSK、QPSK的解调性能恶化在1dB以内,16QAM的性能恶化在2dB以内,通用接收机可以较好地实现PSK和QAM解调.

Universal PSK and QAM demodulation receiver

The paper proposes a variable data-rate receiver on universal PSK(phase shift keying) and QAM(quadrature amplitude modulation) receiver by based on general quadrature architecture,and according to design principle of module sharing and same parameter.In universal receiver,PSK demodulations achieve carrier recovery by Costas loop,and QAM demodulations achieve carrier recovery by constellation-reduced Costas loop.PSK and QAM demodulations achieve timing-recovery by Gardner algorithm.The simulation results of demodulation performance show that: the demodulation performance degrades in 1 dB for BPSK and QPSK,and 2 dB for 16QAM,compared with theoretical values.It is obvious that the universal receiver preferably fulfils PSK and QAM demodulations.