在激光惯性约束聚变(ICF)受激散射光能量信号的检测中，背景噪声的存在严重影响了有用信息的提取。针对该问题，设计了一种新型的可变参数放大滤波电路(VPAFC)，并在降噪源分离(DSS)技术的基础上提出了一种信号降噪方法。采用硬件程控放大、带宽可调滤波以及软件降噪处理相结合的方式，既实现了微弱信号的增益可调放大，又有效抑制了有用信号频带外的噪声和频带内的结构化噪声。为测试所设计电路及噪声抑制算法的有效性，构建了微弱光能量信号检测装置和相关的数据采集系统。实验结果表明，该检测方法不但能程控放大微弱信号，而且当信号低至2 μV时仍能在输出端使信噪比保持在不低于40 dB的水平。

In stimulated scattering energy signal detection of inertial confinement fusion (ICF), background noise has a serious impact on the extraction of useful information. Aiming at this issue, a new variable parameters amplification and filtering circuit (VPAFC) is designed, and a denoising method based on denoising source separation (DSS) is proposed. By using variable gain amplifier, bandwidth-adjustable filter and signal noise reduction software, the whole system can not only adapt to the amplitude change of signal in weak signal detection, but also restrain the noise both outside useful signal band and structural interference inside. In order to test the new circuit and the efficiency of the algorithm, a system with weak scattering light energy signal detection device and data acquisition is constructed. Experimental result shows that the system can fit the amplitude change quickly by adjusting parameters online, and its output can keep a signal-to-noise ratio above 40 dB when the input voltage drops to 2 μV.