Coherent radar

摘要

A coherent radar including separate transmitting and receiving chains. The transmitting chain includes a master oscillator providing a signal at frequency F0. A multiplier multiplies F0 by a predetermined amount to produce a signal at a frequency F1. A second multiplier multiplies the signal at frequency F1 to produce a signal at frequency F2, F1 and F2 being coherent with F0. A first mixer mixes F1 with F0 and a second mixer mixes F2 with the product of the first mixer to produce a transmission signal. In the receiving chain, a received signal is amplified and filtered and then mixed in a third mixer with the second signal at frequency F2 from the transmitting chain. The mixing product of the third mixer is amplified and filtered and mixed in a fourth mixer with the first signal. The fourth mixer product is then coupled to a processor for producing a radar display.