JPS55140180A - Pulse duration lengthening device - Google Patents

Abstract

PURPOSE:To automatic obtain pulse duration lengthening outut of phase continuity and free of deviation in the carrier frequency by providing a delay feedback composite loop having an automatic phase controlling circuit automatically controlling the phase shift quantity of the loop. CONSTITUTION:The phase discontinuity within the pulse of an output 103 generated by mismatching between the delay time of a delay feedback composite loop RL consisting of a pulse width limiter 1, a delay line 2, a superimposition circuit 3, a gate switch 5 and a variable phase shifter 6 and the carrier frequency of an input signal 101, is detected by phase-detecting the side band component of the spectrum of an output pulse wave in a phase detector 7 on the basis of the carrier component and thereafter synchronous-demodulating the same in a synchronous demodulator 12 in the delay circulation synchronizing. The variable phase shifter 6 within the loop RL is controlled so that the above described phase discontinuity becomes zero. By this procedure, the automatic phase control of the loop RL can be carried out with respect to noise generated in the loop RL and external noise.