瑞利信道下基于信号采样自相关的信号检测技术

Signal detection based on sample autocorrelation in Rayleigh fading channel

摘要:

信号检测技术是认知无线电中的首要及关键技术之一。为了提高低信噪比条件下的信号检测性能，采用基于接收信号采样自相关的检测方法来进行授权用户信号检测，并用捕获的数字电视信号以及随机产生的二相相移键控信号作为信号源，在MATLAB中进行信号检测仿真。仿真结果表明，在瑞利衰落信道以及低信噪比(特别是信噪比≤–14 dB)情况下，该检测方法与传统的能量检测方法相比，有较好的检测性能。此外，该检测方法中被检测信号相关性程度对检测概率也有一定影响。

Abstract:

Signal detection is the primary job and the key technology in cognitive radio. In this paper，in order to get a superior detection performance under low Signal Noise Ratio(SNR)，a method based on the sample autocorrelation of received signals is adopted to detect the existence of authorized users’ signals. Then Binary Phase Shift Keying(BPSK) signals and the captured digital television signals are adopted as signal sources to simulate the detection algorithms in MATLAB simulation. The detection results demonstrate that the adopted method outperforms energy detection in Rayleigh fading channel and under low SNR(RSN≤–14 dB) conditions. Moreover，the overall correlation degree of received signals show some effects on detection probability.