A signal modulation method for a receiving-end module of an induction type power supply system includes configuring a plurality of modulation periods corresponding to a modulation signal; performing modulation on a first terminal of an induction coil of the receiving-end module during the ith modulation period among the plurality of modulation periods, wherein i is an odd number; and performing modulation on a second terminal of the induction coil of the receiving-end module during the jth modulation period among the plurality of modulation periods, wherein j is an even number; wherein the second terminal does not undergo modulation when the first terminal is being modulated, and the first terminal does not undergo modulation when the second terminal is being modulated.