基于欠采样随机共振的单频微弱信号检测新方法  

A Novel Weak Single Frequency Signal Detection Method Based on Under-Sampling Stochastic Resonance

作　　者：石盛超[1] 李广侠[1] 李志强[1] 冯少栋 张卫同[1] 

机构地区：[1]解放军理工大学通信工程学院 [2]解放军96610部队

出　　处：《电讯技术》2014年第5期605-610,共6页Telecommunication Engineering

基　　金：国家自然科学基金资助项目(61032004;91338201);国家高技术研究发展计划(863计划)项目(2012AA121605;2012AA01A503;2012AA01A510)~~

摘　　要：由于随机共振具有在特定条件下增强微弱信号信噪比的特性,近年来成为一种全新的微弱信号检测手段。为了克服随机共振绝热近似理论小参数条件的限制,提出一种基于欠采样随机共振的微弱信号检测方法。通过欠采样尺度变换与还原技术,实现了大参数信号的随机共振处理,突破了二次采样变尺度随机共振算法要求采样频率必须大于信号频率的50倍的限制。构建了基于欠采样随机共振的微弱信号检测模型,从理论上证明了方法的可行性。最后利用该方法对信噪比为-27 dB条件下的微弱单频信号检测进行了仿真,结果进一步验证了所提微弱信号检测方案的正确性。所提方法大大降低了信号的采样速率,为将随机共振应用于科斯塔斯(Costas)环的改进奠定了基础。Stochastic resonance is widely applied to detect weak signal in a strong noise background be-cause it can enhance the signal-to-noise ratio（SNR）. A weak single frequency signal detection method based on under-sampling stochastic resonance is proposed to solve the problem that traditional stochastic resonance can be only applied to deal with small parameter signals. Stochastic resonance is successfully ex-panded into the applications of the large parameter signals on the basis of scale-transformation and retrieve technology in the under-sampling stochastic resonance. Moreover,the algorithm overcomes the limit that signal frequency must be more than 50 times of the sampling frequency in the second sample algorithm. The model of weak signal detection based on under-sampling stochastic resonance is put forward. Finally, detecting the weak single frequency signal under SNR=-27 dB background by the method proposed in this paper is simulated. The result proves the validity of the method. The sampling frequency in the method is much less than that in the traditional methods and this is helpful to apply stochastic resonance in improving the performance of the Costas loop.

关 键 词：深空通信 微弱信号检测 随机共振 欠采样 尺度变换 

分 类 号：TN911.72[电子电信—通信与信息系统]