During the energy transmission process of wireless charging, a transmitting terminal needs to detect an input signal transmitted by a receiving terminal firstly; however, in practice, the input signal is disturbed by various noises and thus detection and determination on the receiving terminal signal by the transmitting terminal are affected. According to the invention, dual detection is carried out on an input signal by the transmitting terminal, thereby eliminating the disturbance and thus guaranteeing execution of the wireless charging function.