基于缓变信号消除的数字通信系统信噪比盲估计算法

Blind SNR Estimation of the Digital Communication Systems Based on Slowly Changing Signal Elimination

针对认知无线电中的频谱分析问题,在软件无线电构架下给出一种数字通信系统信噪比盲估计模型。分析了数字通信系统中缓变区的存在性,并根据数字通信信号的循环平稳特性给出了信号缓变区的选择方法。提出了一种基于缓变消除的信噪比盲估计算法,该方法不需要通信系统发送目标波形。仿真分析表明,所提方法能够准确找到数字通信信号的缓变区,对各种数字通信系统都具有较好的信噪比估计性能。

The blind SNR estimation model of the digital communication systems based on software radio technology is given to approach spectrum analysis problem for cognitive radio systems.The slowly changing regions in digital communication waveforms are analyzed to be existent,and the method to find these regions is given according to digital communication signal＇s cyclostationarity.A new blind SNR estimation algorithm based on slowly changing signal elimination is presented without any reference waveform transmitted by the communication system.Simulations show that the methods proposed by this paper can find the slowly changing regions exactly,and can estimate different digital communication system＇s SNR with preferable precision.