We proposed a novel wideband super-heterodyne receiver based on nonlinear blind identification and compensation processing.This process was specifically designed as follows.Firstly,we extracted small signals,mainly consisting ofnonlinear distortion component,and large signals (high power frequency component) of output signal of receiver front-end in time domain respectively.In addition,we designated a blind identification criterion of the nonlinear behavior model---to minimize the residual sum of squares between the small signals and nonlinear model of large signals.Moreover,the improved weighted iterative algorithm was applied to extract and update the parameters of the nonlinear behavior model.The effect of the updated model kernel coefficients,finally,can achieve to compensate online the nonlinear distortion of the receiver in real time.The experimental results demonstrate that,this processing could make the entire receiver nearly achieve above 20 dB improvement of Spurs-Free-Dynamic-Range (SFDR) under the circumstances of receiving multi-signals simultaneously,and the ability of the novel receiver to receive and detect weak signals could be improved significantly when it comes to strong interference.%提出了一种基于非线性盲辨识补偿处理的新型宽带超外差接收机.在时域,分别提取接收前端输出信号的大信号成分(大功率频率分量)和小信号成分(主要包含非线性失真分量),并以大信号的非线性模型与小信号的残差平方和最小作为其非线性行为模型参数的辨识准则,利用加权迭代改善算法实现模型参数的自适应提取和更新,最后在线实时地对接收机输出信号进行数字域后补偿处理.实测结果表明,在同时多信号接收的情况下,该非线性盲辨识补偿处理可将整机的无杂散失真动态范围提高超过20 dB,极大地提高了在强干扰存在时对微弱信号接收与检测的能力.
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