本文讨论了采用锁相环路作为本振信号的混频器对本振锁相环路的影响。当混频器对已调频信号进行混频时,混频器中由于低频调制信号频率Ω的影响,使本振信号产生调幅,而这个调幅波又反过来影响了本振锁相环路,使其输出调频波。因而使混频器失真;甚至使本振锁相环路失锁。本文对上述现象产生的原因进行了定量的分析,并提出了防止的措施。 This article discusses the effects of a mixer that uses a phase-locked loop as the LO signal on the PLL. When the mixer frequency modulated signal is mixed, the mixer due to the low-frequency modulated signal frequency Ω, so that the local oscillator signal amplitude modulation, and this amplitude modulation wave in turn affect the LO PLL, so that Its output FM wave. Thus distorting the mixer; or even losing the lock to the phase locked loop of the local oscillator. In this paper, the reasons for the above phenomena were quantitatively analyzed and measures to prevent them were put forward.