摘要
提出的ＭＴＩ雷达模拟相干补偿理论，是以声表面波存贮相关卷积器作为中央处理单元，将每一周期的发射脉冲与其回波做复共轭相关处理，并做幅度归一化，因而消除或减小由于发射系统不稳定对改善因子的限制，从而使老式ＭＴＩ雷达的性能达到或接近全相参雷达的水平．这是一种新型接收相参体制，可用于老雷达的改造与新雷达的设计．
The low improvement factor of coherentonreceive moving target indication (MTI ) radars restricts their capability to detect lowflight objects .System instabilities place a limit on MTI performance. These instabilities come from the transmitter pulsetopulse frequency change, from pulsetopulse phase change or instabilities to lock the coho perfectly to the phase of reference pulse, and from time jitters and amplitude jitters on the pulses .Many efforts have been made to improve the characteristics of video canceler, but are insignificant to increase improvement factor, for video cancellation can not eliminate instabilities of transmitting system .In this paper, we present the theory of analog cherent compensation for MTI radars, the theory utilizes surface acoustic wave (SAW) memory correlators as a central processing unit, and through coherent compensation, the limit on improvement factor caused by system instabilities is eliminated or greatly reduced, so the attainable improvement factor can be more than 40 dB.The procedure of coherent compensation is as follows : for each repetition cycle, the intermediatefrequency sample of transmitted pulse is stored onto SAW memory correlators; and when the reflected signals arrived, a complex correlation of the sample and each received pulse is then performed by the SAW correlators. These signals are of intermediate frequencies, and then amplitude of each correlation output is subsequently normalized. Thus the pulsetopulse jitters are removed from the processed signals, the limit on improvement factor caused by system instabilities is eliminated or greatly reduced. This coherent compensation is a new coherentonreceive regime, and can be used for the modification and design of coherentonreceive MTI radars.
出处
《南京大学学报（自然科学版）》
CAS
CSCD
1998年第1期64-70,共7页
Journal of Nanjing University（Natural Science）
关键词
相干补偿
动目标雷达
声表面波
存贮相关卷积器
coherent compensation
coherentonreceive MTI radar
improvement factor
SAW memory correlator
