基于信号高阶统计矩分析的信噪比盲评估算法

Signal-to-Noise Rate Blind Estimation Algorithm Based on the High-Order Moment Analysis of Received Signals

正确地进行信噪比(SNR)评估是CDMA系统进行有效通信的基础,也是某些算法实施的基础,如功率控制、多径搜索与跟踪等。传统的方式中,往往以接收到的信号幅度(信号+噪声)的大小来判断接收信号质量,这在SNR较大的情况下是可行的,但在小信噪比条件下,由于噪声干扰严重,接收信号幅度的大小,不能反映接收信号质量水平。只有接收信号SNR的大小,才能反映接收信号的实际质量。本文提出了一种基于信号高阶统计矩分析的SNR盲评估算法,计算机仿真结果表明,该算法较其他算法有更好的适应性。

It is essential to estimate the Signal-to-Noise Rate correctly for CDMA systems, and for usages of some algorithms used in CDMA systems, such as transmission power-control, path searching and tracking. The receiving signal amplitude （signal ＋ noise） is usually used to measure the receiving signal quality. It is successful at high SNR, but not suitable for low SNR, because it is hard to indicate the receiving signal quality with receiving signal amplitude. It is only SNR that can denote the true level of signals. A new algorithm for blind SNR estimation based in high-order moments is proposed in this paper. The results of computer simulation show that the new algorithm has wider adaptability to SNR conditions.