Automatic frequency control circuit for frequency agile radar

摘要

An automatic frequency control circuit for frequency agile radar systems. Fundamentally, the invention utilizes two oscillators of different frequencies and which are controlled by the IF pulse envelope. The outputs of the oscillators are monitored until such time that corresponding transition points of the outputs coincide. A counter, receiving the output of one of the oscillators, is then decoded at the time of coincidence and the resulting value, being a function of deviation of the IF pulse from a desired frequency, is applied to the radar system as an error correction signal.