| 摘要 |
A coherent-on-receive radar for determining the velocity of and distance to targets. The radar conventionally includes a transmitter of non-coherent pulses, an antenna for transmitting the pulses into space and receiving return signals from targets upon which the pulses impinge, a local oscillator and a phase detecting circuit responsive to the return signal and local oscillator signal for determining the phase difference between the respective signals. In accordance with the invention the radar includes a sample and hold circuit used in conjunction with the phase detecting circuit, prior to the receipt of any return signal, for storing for each transmitted pulse its phase difference from the local oscillator signal phase. The stored signal is used to modify the phase of one or the other of return signals sent to the phase detector or local oscillator signal as sent to the phase detector so the detector in effect detects the phase difference between each transmitted pulse and the return signals resulting therefrom.
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