Chaos Synchronization Based on Phase-Locked Loops

The experimental confirmation about the synchronization between two similar phase-locked loops is provided. The pair of PPLs is driven by a common chaotic signal which is derived from a master PLL. The parameters of the PLLs must be properly and particularly chosen to ensure the robustness of this synchronization system. Firstly, in order, the characteristics of PLL are discussed in detail. Then the synchronization model is given and the mathematic model of the system is built. The simulation results prove the anticipated purpose to synchronize between 2 PLLs. Then circuit model is built also and the simulation results also prove to be feasible. Experimental observations are qualitatively consistent with both math simulations and with the recent synchronization criterion due to Pecora and Carrol. The robustness of this synchronization scheme suggests the intriguing possibility of using chaos as the scrambling codes or spread spectrum communications.