This work studies four carrier phase synchronizers (CPS) or carrier Phase Lock Loop (CPLL). The synchronizers are based in a loop with VCO (Voltage Controlled Oscillator) that synchronizes the output feedback with the input. We consider four carrier synchronizers namely the analog, hybrid, combinational and sequential. The difference between them is in the phase comparator. The main objective is to study the synchronizers output jitter UIRMS (Unit Interval Root Mean Square) versus input SNR (Signal to Noise Ratio).