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公开(公告)号：US5081459A
公开(公告)日：1992-01-14
申请号：US614135
申请日：1990-11-16
IPC分类号： G01S13/52 , G01S7/292 , G01S7/41 , G01S13/524
CPC分类号： G01S7/415 , G01S13/5246
摘要： This Doppler radar for the detection and localization of helicopters through blade flashes works in a band located between 300 MHz and 20 GHz and identifies the blade flashes by the width of their frequency spectrum and their duration. It uses, at reception, a multilobe antenna associated with several parallel signal processing chains specialized in the detection of helicopters, enabling detection over a widened zone as well as precise localization. Each chain has a phase amplitude detector PAD (10, 10') followed by a Doppler filter MTI (20, 20') selecting the wide frequency spectrum, a module computing circuit (30, 30'), a contrast circuit (40, 40') eliminating excessively long echoes, a threshold circuit (50, 50') and a false alarm reduction circuit FAR (60, 60') eliminating excessively short echoes. The chains lead to a relative bearing computation circuit (100) performing angle measurements when this is possible.
摘要翻译： 这种用于通过叶片闪光检测和定位直升机的多普勒雷达在位于300MHz和20GHz之间的频带中工作，并且通过其频谱的宽度及其持续时间来识别叶片闪烁。 它在接收时使用与多个并行信号处理链相关联的多叶天线，专门用于检测直升机，使得能够在加宽区域上进行检测以及精确定位。 每个链具有相位幅度检测器PAD（10,10'），随后是选择宽频谱的多普勒滤波器MTI（20,20'），模块计算电路（30,30'），对比电路（40,40） '）消除过长的回波，阈值电路（50,50'）和消除过短的回波的假警报降低电路FAR（60,60'）。 当可能时，这些链通过执行角度测量的相对轴承计算电路（100）。
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公开(公告)号：US4308535A
公开(公告)日：1981-12-29
申请号：US86429
申请日：1979-10-19
IPC分类号： G01S7/292 , G01S13/22 , G01S13/528 , G01S7/04
CPC分类号： G01S13/225 , G01S13/528 , G01S7/2923
摘要： In a moving-target indicator in which the pulse-repetition period of an associated Doppler radar is subject to variation, incoming echo pulses appearing in the output of an i-f stage of the radar receiver are demodulated with the aid of two coherent reference signals in relative quadrature and the results are digitized for transmission over two parallel channels. In each channel, digitized signals corresponding to two consecutive echoes in a given range cell are subtracted from each other to provide a pair of difference signals which are passed through a weighting device for multiplication by factors which are trigonometric functions of a selected Doppler frequency and of the difference between the actual repetition period and a theoretical constant value of that period. The weighted signals are subjected to further filtering before being utilized for further processing or display.
摘要翻译： 在相关联的多普勒雷达的脉冲重复周期经历变化的移动目标指示器中，出现在雷达接收机的一级的输出中的输入回波脉冲借助于相对的两个相干参考信号进行解调 正交并将结果数字化以便在两个并行通道上传输。 在每个通道中，对应于给定范围单元中的两个连续回波的数字化信号彼此相减，以提供一对差分信号，该差信号通过加权装置，以乘以所选择的多普勒频率的三角函数和 实际重复期与该期间的理论常数值之间的差异。 加权信号在被用于进一步处理或显示之前经过进一步的滤波。
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3.发明授权Method and device for compensating for the speed of clutter in a coherent doppler radar with variable blind speed 失效用于补偿具有可变盲速度的相干多普勒雷达中的杂波速度的方法和装置
公开(公告)号：US4972194A
公开(公告)日：1990-11-20
申请号：US253108
申请日：1988-10-03
IPC分类号： G01S13/22 , G01S13/524
CPC分类号： G01S13/524 , G01S13/227
摘要： In a doppler radar, in order to compensate for the speed of moving clutter, one first establishes during a burst of order (i) the phase variation .phi.r.sub.i from one period to the next and which is due to clutter in a given range cell. Then, this phase variation .phi.r.sub.i is memorized and is used during the course of each of the periods of repetition of the next burst to modify the phase of the signal received from the clutter from the same range cell in a maner as to displace its Doppler frequency towards the zero frequencies band, and band which corresponds to the rejection zone of the fixed echoes eliminating filter.
摘要翻译： 在多普勒雷达中，为了补偿移动杂波的速度，首先在一个脉冲串期间（i）从一个周期到下一个周期的相位变化phi ri建立，并且这是由给定范围单元中的杂波造成的。 然后，存储该相位变化步骤，并且在下一个脉冲串的重复周期的每个周期的过程中使用，以修改从操纵器中的相同范围单元从杂波接收的信号的相位，以便移位其多普勒 频率朝向零频带，以及对应于固定回波消除滤波器的抑制区的频带。
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