Abstract:The fast frequency hopping principle, composition and implementation of a simple and reliable digital phase-locked frequency synthesizer is introduced. A resistance switching network is adopted for Phase-Locked Loop(PLL) presets. The hopping speed is improved under the premise of keeping the phase noise, spurs and other indicators unchanged. The actual tests indicate that the proposed method can realize the fast frequency hopping process preset of phase-locked circuit, and accelerate the frequency hopping speed.