摘要
自动调制方式识别是非协作通信研究中的重要内容。本文研究了基于决策理论的数字通信信号调制方式识别技术,并给出了一种基于检测理论的调制方式识别算法,用于加性高斯白噪声信道内PSK(相移键控)与QAM(正交幅相键控)信号的识别。算法首先对接收到的信号进行幅度归一化处理,提取其中的相位信息,由接收信号的似然函数公式推导出不同信号的似然比,将2种信号的分类问题转化为门限检测问题。该算法步骤简单,可在低信噪比情况下实现对PSK/QAM信号进行分类。仿真结果表明:在4dB信噪比时,识别成功率可达到90%。
Automatic modulation classification is an important research area in the non-cooperative communication systems. In this paper, the modulation recognition technology for communication signals based on testing theory is studied and an algorithm for modulation classification is proposed, which is used to distinguish PSK/QAM signals embedded in additive white Gaussian noise（AWGN）. The reeeived signal is processed, and phase information is picked up, different signals＇ likelihood ratio is deduced from the likelihood function formula for received signals. The matter of two signals classification is thus transformed to a threshold-checking problem. The step of this algorithm is simple and high computation effieiency can be achieved. The classification for PSK/QAM in low signal noise ratio （SNR） can be achieved. Simulation results show that the scheme can achieve 90% recognition accuracy when SNR is above 4 dB.
出处
《电子测量技术》
2007年第2期6-7,14,共3页
Electronic Measurement Technology
