中文摘要：

本文根据小波变换具有时频分析的特点,提出一种通信系统中QPSK（quadrature phase shift keying）信号解调的新方法。该信号解调新方法与传统的QPSK相干解调方式不同之处在于,首先它是直接对接收到的QPSK信号中的频率和相位（相当于瞬时值）进行提取和判决,是一种具有多分辨特性的时频分析检波方法;其次,发送端信号和接收端信号之间不需要严格同步,是一种“盲检测”方法。仿真结果表明：该新的信号解调方法在抗噪声性能和抗复杂信道的鲁棒性等方面具有比传统解调方法更优异的性能。

英文摘要：

According to the characteristics of the time-frequency analysis of the wavelet transform, a novel QPSK（quadrature phase shift keying） signal demodulation method in the communication system is proposed. The novel demodulation method for QPSK signal is different from the traditional demodulation method. First of all, it can directly extract and decide the frequency and phase （equivalent to the instantaneous value） of the received QPSK signal and it is a time-frequency detection method which has the multi-resolution properties; second, it is a ＂ blind detection＂ method without strict synchronization between the transmitter signal and receiver signal. The computer simulation results show that the novel signal demodulation method has better performance than the traditional one in antinoise property and robustness of anti complex channel.