摘要
使月小波分析的方法,时星间激光通信中接收系统接收到的带噪信号进行降噪研究。由于背景光噪声的影响,导致系统接收到的有用信号功率下降。使用小波函数和小波包的分析方法对带噪信号进行分解,将其转换为小波系数;采用软阈值门限法去掉信号小波系数中小于设定阈值的较小值,通过得到的系数重构信号就可以达到降噪的目的。仿真结果表明选用1 GHz的信号时,用小波降噪的方法对带噪信号进行处理,可以把信噪比提高1.5～2.5 dB。
This paper proposes a method of wavelet analysis for denoising the noisy signal at the receiver system in inter-satellites laser communication.Background noises make the received signal power reduce.The noisy signal is decomposed using wavelets and wavelet packets,then it is transformed into wavelet coefficients and the lower order coefficients are removed by applying a soft threshold.Denoised signal is obtained by reconstructing with the remaining coefficients.Simulation results indicate that if wavelet denoising method is used to process the noisy signal,the Signal to Noise Ratio(SNR)will be improved by 1.5 dB to 2.5 dB when the signal frequency is 1 GHz.
出处
《电子科技大学学报》
EI
CAS
CSCD
北大核心
2007年第S2期1092-1094,共3页
Journal of University of Electronic Science and Technology of China
关键词
背景光噪声
降噪
星间激光通信
接收系统
小波变换
background noise
denoising
inter-satellites laser communication
receiver system
wavelet transform
