This is just the velocity of the source relative to you at that Angle.

这是源在这个角度，向你们移动的速度。

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For the case of planar interception, the so called relative heading error angle between the relative velocity vector and the LoS (Line of Sight) is chosen as the output to be controlled to zero.

针对平面拦截问题，选择导弹和目标之间的相对速度矢量与导弹-目标视线之间的夹角（称为相对航向误差角）作为将要被控制到零的输出。

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The cost of the system is reduced and the structure is predigested, and it makes the detection system can measure distance, relative velocity and azimuth angle at the same time.

这样做既提高了系统的经济性，简化了结构，又使得系统具有了同时测量目标距离、相对速度和方位角的功能。

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