A mixer oscillator with a phase-locked loop control loop for a radio receiver is described in which a digital loop filter in the control loop includes which an integrator for digital output signals of a phase discriminator which is preprogrammed frequency jumps. The digital loop filter includes two switchable...http://www.google.com.tw/patents/US6091943?utm_source=gb-gplus-share專利 US6091943 - Combining oscillator with a phase-indexed control circuit for a radio receiver
