(一) 引言频率综合在通讯、控制及精密守时系统的电子设备中起着重要作用。通常要求综合出一个与给定基准频率偏移小的新频率,并且,使它具有非常高的频谱纯度和稳定度。一般,采用双平衡混频器或环形调制器来完成上述任务。这些技术要求仔细地进行相位与振幅的平衡,以达到高的频谱纯度,可是,用简单的方法是难以实现上述要求的。近年 (A) Introduction Frequency synthesis plays an important role in the electronic equipment of communication, control and precision punctuality systems. It is often desirable to synthesize a new frequency that is less offset from the given reference frequency and to have a very high spectral purity and stability. In general, dual balanced mixers or ring modulators are used to accomplish this. These techniques require careful phase and amplitude balance in order to achieve high spectral purity, however, with simple methods it is difficult to achieve the above requirements. in recent years