摘要
从通用正交解调的基本思想出发,提出一种PSK非相干差分解调方法,将载波频率的频偏转化为点积和差积的相位偏移,同时采用包络平方滤波的定时同步方法,因此具有很强的抗频漂能力。通过理论分析,推导出解调算法公式,给出了解调器结构,并得到解调算法的抗频漂门限。针对BPSK、DPSK、QPSK和DQPSK四种常用的PSK调制模式进行了仿真,验证了算法的正确性。
A non-coherent differential demodulation method is presented. The frequency deviation is translated into the phase deviation of the dot product and cross product, and the timing clock is recovered from the square of the signal envelope. Thus the demodulation method is not sensitive to frequency drift. The demodulation formula is deduced, and the structure of the demodulator given. Based on theoretical analysis, the threshold of the anti-frequency deviation capability is achieved. Finally, the simulation model is built and the four modulations, including BPSK, DPSK, QPSK and DQPSK, are simulated. The simulation results shows that the demodulation method is correct and effective.
出处
《通信技术》
2009年第9期12-15,共4页
Communications Technology
关键词
PSK
非相干差分解调
点积
差积
PSK
non coherent differential demodulat
dot product
cross product
