A pulse compression system employing a linear FM Gaussian signal

Some of the factors involved in the design of a radar pulse compression system are discussed. These include the compression ratio, the detailed characteristics of the signal, the sidelobe level of the receiver output waveform (signal autocorrelation function), the sensitivity of the sidelobe level to Doppler frequency shift in the signal, and the relative complexity of the equipment required to generate and receive the signal. A signal of Gaussian envelope and linear frequency modulation is shown to have an autocorrelation function of Gaussian shape. When the receiver is designed to autocorrelate the linear FM Gaussian signal, it is shown that the shape of the receiver output waveform does not change when the input signal has a Doppler frequency shift. The design and construction of equipment used to generate and receive the signal are discussed. In operating equipment with a compression ratio of about 50 to one, sidelobe levels 40 db below the peak amplitude of the receiver output waveform are achieved, and the shape of the receiver output wave-form does not change appreciably until the Doppler frequency shift exceeds 25 per cent of the 3-db signal bandwidth.     

线性调频脉冲压缩雷达杂波统计模型分析

对线性调频脉压雷达杂波进行建模与仿真以及统计性分析,在雷达信号模拟领域中是非常重要的.给出了线性调频脉压雷达杂波模型以及仿真方法,并在以往对杂波特性研究的基础上,分析了杂波的分布特性、时间相关特性以及空间相关特性.对比常规脉冲雷达杂波,由于叠加效应,杂波统计特性有所不同.     

Pulse compression with very low sidelobes in an airborne rainmapping radar

Pulse compression allows a substantial reduction in the peak transmitted power of a radar and is attractive for spaceborne remote sensing applications. In the case of a downward looking rain measuring radar, however, the range sidelobes associated with surface return can mask return from rain and must be kept to a minimum. The authors describe the pulse compression system for the NASA/JPL Airborne Rain Mapping Radar. This system uses time-domain weighting of the transmitted pulse and is able to achieve a range sidelobe level of -55 dB or better in flight tests. This is significantly lower than other values reported in the open literature     

The design of FM pulse compression signals

This paper gives a procedure for designing an FM signal of arbitrary envelope shape so that it will have a specified spectral modulus and hence, a specified autocorrelation function. The design procedure, which is based upon an approximate analysis, gives best results when the duration-bandwidth product of the signal is large, and it is therefore useful in the design of pulse compression signals. Examples are given to illustrate the design procedure and to show in a general way how the quality of the approximate solution depends upon the duration-bandwidth product of the signal and upon the shape of the signal envelope and the modulus of the signal spectrum.     

Suppression of range sidelobes in bistatic radars

Conventional weighting schemes give little or no suppression of some of the range sidelobes of a linear-FM rectangular pulse passed through a matched filter.     

脉冲压缩技术在相干激光雷达中的应用研究

脉冲压缩技术在微波雷达、无线通讯领域有着广泛的应用,但在相干激光雷达特别是相干激光测距领域应用较少。本文将脉冲压缩技术应用于相干激光雷达系统中,对脉冲压缩相干激光雷达进行理论分析和性能分析,分析可见脉冲压缩技术可显著提升相干激光雷达的性能。     

脉冲压缩在超宽带雷达中的应用

超宽带（UWB）雷达是一种新体制的雷达系统,其极大的带宽和分辨率使它具有广泛的应用前景。典型的超宽带雷达系统发射的是冲激脉冲信号,具有很大的带宽,但限制了系统的作用距离。为了解决这一矛盾,本文将脉冲压缩应用于超宽带雷达系统中,并进行了仿真研究,结果证明了脉冲压缩使系统性能得到较大提高。     

脉冲压缩及相参积累在激光雷达中的应用

将现代微波雷达中的脉冲压缩及相参积累技术应用到激光雷达中,通过搭建激光雷达实验系统,对目标回波数据进行采集分析,数据处理结果表明,激光雷达应用脉冲压缩及相参积累技术后,可以显著提升激光雷达系统的性能。     

Comments on `Sidelobe suppression in low and high time-bandwidthproducts of linear FM pulse compression filters' [and reply]

For the original article see ibid., vol.MTT-35, no.9, p.807-11 (1987). K.M. El-Shennaway, et al. computed the sidelobe suppression of linear FM pulse compression filters using Hamming weighting functions. The commenter states that the authors' claim of achieving lower insertion loss in higher time-bandwidth products is wrong, and that the research is itself only a repetition of 20-year-old work. In replying the author maintains the validity of the original claim     

基于DDS技术的线性调频脉冲信号的产生

随着数字信号处理技术的发展,DDS技术被越来越广泛的应用于各种数字系统中,它是一种基于数字电路的频率合成方法,随着各种大规模数字可编程芯片的出现,使用DDS有效地解决了模拟电路频率合成技术对相位和频率控制的复杂性和误差较大的特性.首先介绍了DDS技术的基本工作原理和结构,然后用Verilog硬件编程语言实现了基于DDS的信号发生,在此基础上设计了一种基于DDS技术的多路线性调频信号,并给出了其仿真结果,验证了其正确性.     

基于FPGA的雷达脉冲压缩系统设计

脉冲压缩技术是指对雷达发射的宽脉冲信号进行调制(如线性调频、非线性调频、相位编码),并在接收端对回波宽脉冲信号进行脉冲压缩处理后得到窄脉冲的实现过程.脉冲压缩有效地解决了雷达作用距离与距离分辨率之间的矛盾,可以在保证雷达在一定作用距离下提高距离分辨率.     

脉冲压缩激光雷达多普勒补偿方法北大核心CSCD

激光雷达动目标引起的多普勒频移较大,无法有效进行脉冲压缩且距离与速度耦合严重,严重影响激光雷达动目标检测性能及测距精度,针对上述问题,本文提出一种多普勒补偿方法,该方法采用双频共轭处理求解速度模糊,然后对目标进行多普勒补偿,同时解决激光雷达动目标距离速度耦合及脉压性能问题,提高目标检测性能和测距精度。采用目标回波仿真数据进行实验,实验结果表明了本文方法的有效性。     

Implementation of nonlinear FM pulse compression filters using surface wave delay lines

The synthesis of a surface wave pulse compression filter with a non-linear FM dispersion relation to reduce time sidelobes is described. The significance of this synthesis is discussed and a comparison of the use of nonlinear FM and amplitude weighting of linear FM is made with regard to surface wave synthesis.     

基于移频滤波的脉压雷达抗干扰方法

针对线性调频(LFM)脉冲压缩雷达易受移频欺骗干扰影响的问题,提出了基于移频检测的起始频率捷变LFM雷达抗干扰方法.通过分析匹配滤波器参考函数、目标回波信号和干扰信号在频域的相对位置,利用脉间LFM信号起始频率不同的特点,将接收信号进行移频,使得目标回波信号分量无脉压输出,从而确定干扰信号分量在时域的位置,通过时域选通对未进行移频的接收信号脉压结果中的干扰进行滤除达到抗干扰目的.仿真分析了移频检测抗干扰性能,结果验证了所提方法的有效性.     

New ideas in FM radar

FM radars represent one of the oldest and simplest-yet at the same time one of the most versatile types of radar. The author presents a tutorial review of the basic principles of FM radars and introduces a number of new ideas, including digital generation of wideband linear FM waveforms, and aperture synthesis with FM radar     

大时宽带宽雷达信号高速脉压技术研究

以大时宽带宽雷达应用为背景,提出利用FPGA完成高速脉冲压缩的方案。对双通道正交和FPGA实现频域脉压作了详细分析。结果表明,该技术对大时宽带宽雷达实时得到高分辨一维距离像（HRRP）有重要意义。     

基于APC技术的空间分集MIMO雷达目标检测

为有效地抑制样本随机性的影响,改善MIMO雷达的检测性能,通过分析已有的基于迭代最小均方误差(RMMSE)估计和迭代最大化输出信噪比(RMSNR)准则的APC技术,指出样本随机性是影响以迭代APC技术为基础的检验统计量检测性能的重要因素。提出基于RMMSE和RMSNR的多通道多脉冲平均APC(MMA-APC)技术,并以此为基础构造检验统计量。基于自适应脉冲压缩(APC)技术研究了空间分集MIMO雷达相参脉冲串条件下的目标检测问题。