First please make sure the useful signal has very good snr before you input it to amplifiers chain , then you can calculate how much gain and nf you need to get the targeted signal amplitude and noise level , based on this you can choose the right components to design amplifiers chain 后才将其输入放大器链，接着计算获得目标信号振幅和噪声水平所需的增益与nf的大小，最后根据这些数据选择合适的器件设计放大器链路。
Theoretical analyze and computer simulation prove that the side lobe canceller system using polarization radar can depress jammer while not damaging the signal , the overall performance is better than that of the system using polarization radar only in the auxiliary antenna 理论分析和仿真实验表明使用全极化雷达的旁瓣对消系统,可以在抑制干扰的同时尽量不损失目标信号,系统整体性能优于主天线为单极化时系统的性能。
This paper depicts a signal processing system for lfmcw radar . this system is mainly used to eliminate noise interference in the sampled signal , check out the objective signal , and send the processing results to a computer via networks 本论文着重叙述了一种基于lfmcw雷达信号处理系统,该系统主要用于从采样后得到的信息中消除噪声干扰,检测出目标信号,并能将最终的处理结果数据通过网络接口传给计算机,经计算机处理后显示出来。
With the theory of wavelet analysis , the decomposition of the signal is localized . the characteristic of the signal can be analyzed in different levels , conforming to the basic methods of human brains " work style . wavelet analysis is becoming a useful tool in radar signal processing now 小波分析理论对信号的分解具有良好的局域化特性，运用小波分析理论可以在多尺度下分析目标特征，符合人脑对信息加工的基本特点，成为雷达目标信号处理强有力的数学工具。
Within one single source echo , both doa and time - delay can be estimated simultaneously by this algorithm via high - resolution rotational invariance technique and high - resolution time - delay frequency ( tdf ) technique . the esprit - tdf algorithm has features of low computation , good precision , and high resolution both in doa and time - delay . it is suitable for multiple source exact localization 该方法利用高分辨旋转不变技术和高分辨时延频率技术，可在单次目标回波内实现多目标信号的方位和时延参数的高分辨联合估计，具有运算量小、分辨能力强、估计精度高等特点，能够对多目标进行高分辨精确定位。
A kind of mathematical model about the output signal of the millimeter wave radiometer sensor is established . through analyzing and abstracting the output signal , we devised the target template . after previous transaction , use the fuzzy theory to calculated the target recognition probability , including the low speed scan and the high speed scan 建立了毫米波辐射计输出信号波形的数学模型，通过波形特征分析和提取，分别设计了高、低速扫描条件下的目标模板，提出了一套对目标信号进行预处理的方法，并运用模糊目标识别理沦，分别计算了高、低速扫描条件下的目标识别概率。
Then compound - gaussian distribution model is been introduced and the three adaptive algorithms been derived from the model . by using simulation data and ipix radar sea clutter data that is been added target signals the performances of the detection algorithms are been simulated and analyzed . the same conclusion and the adaptive algorithms " effectiveness are been shown 接着介绍了复合高斯分布模型,在此模型基础上推导得到了三种自适应检测算法,通过使用仿真数据和ipix雷达实测海杂波数据加入目标信号对三种算法检测性能进行了仿真分析和比较,得到了相一致的结果,证明该算法的有效性。
Through the analysis of the test data and the new development in the relevant literature , some more realistic models for sea - clutter and multipath propagation is concluded and the simulation is accomplished in the software . they provide the foundation for low - altitude radar target detection & tracking techniques research . in the second part , radar low - altitude target detection & parameters ( elevation - azimuth - range delay - doppler shift ) measure are studied (海)杂波和目标信号的多径传播严重影响了雷达低空目标探测与跟踪的性能，通过分析国内外的有关试验数据和最新的研究进展，总结出比较接近实际的海杂波和多径传播模型，并在有关软件中实现了海杂波与多径传播的仿真，为进一步研究各种低空目标探测与跟踪测量算法提供了保证。
High accuracy correlative detection technology of object signal is to search and detect objects by optical correlation , and it can detect real - timely , recognize automatically and orientate precisely , optical correction processes images at light speed and its device is simple , and fourier transformation can be realized 高精度光学目标信号相关测试技术，利用光学相关探测方法，对要搜索、探测的目标进行实时探测，自动识别，高精度定位。光学相关是以光速进行的，处理速度快，结构简单，利用由空间域到频率域的傅立叶变换来实现的，本文针对如何设计傅立叶变换系统实现光学相关进行研究。
The feature parameter extraction methods of the underwater target are studied which can improve the performance of the underwater acoustic countermeasure equipments . several feature extraction methods such as the scale invariance feature extraction , target pole extraction fourier - mellin transform etc are investigated by computer simulations . the experimental results demonstrated the efficiency of these feature extraction methods in the applications of underwater target recognition 对多种特征提取方法如目标相对不变尺度特征提取、目标极点特征提取、目标信号的傅里叶?梅林变换特征提取等进行了仿真研究，结果表明了这些特征参数提取方法的有效性，具有良好的应用前景。
