本文探讨了雷达波束在目标场上扫描时对理想点散射体的响应特性。当雷达视线对准散射体时，其响应达到最大；反之，响应会减弱。若两个散射体距离很近，则它们的响应可能融合成一个峰值。此过程受散射体间相对相位的影响，会产生不同的复合响应。
雷达在目标场的方位角度上扫描，此时，理想点散射阵列被雷达波束照射。
An array of idealpoint scatterers is illuminated by a radar that scans in azimuth across thetarget field.
当雷达视线对准任何一个散射体时，则该散射体的响应最大；当雷达视线移开时，由于发射波束指向散射体的能量较少，回波强度降低，接收天线对非视线方向返回的回波信号不太敏感。
The response to anyone scatterer is maximum when the radar boresight is aimed at that scatterer;as the radar boresight moves away, the strength of the echo declines becauseless energy is directed to the scatterer on transmission, and the antenna isalso less sensitive to echoes from directions other than the boresight onreception.
因此，接收信号的图形类似于天线的双程方位电压方向图。
Thus, a graph of thereceived signal mimics the antenna two-way azimuth voltage pattern.
假设采用一个线性接收机，则对两个近距离点散射体的响应分别与天线方向图成比例，二者相叠加以获得接收机输出的复合响应。
Assuming a linearreceiver so that superposition applies, the response to two closely spacedpoint scatterers is proportional to two replicas of the antenna pattern,overlapped and added to get a composite response.
如果两个散射体之间足够接近，则单个独立响应不会被分辨，而是模糊成一个峰值，如图2.26所示。
If the two scatterersare close enough together, the individual responses are not resolved, but insteadblur together into a single peak as illustrated in Fig. 2.26.
这种散射体叠加组合响应的细节取决于两个单独响应的相对相位；它们可以在相位内或相位外组合，产生明显不同的复合响应输出。
The details of thecombined response depend on the relative phase of the two individual responses;they may combine in or out of phase, yielding significantly differentcomposites.
——本文译自Mark A. Richards所著的《Fundamentals of Radar Signal Processing（Second edition）》
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