Backscatter communication system and method

The invention provides a backscatter communication system and method, and belongs to the technical field of wireless communication. A first device circularly sends a frequency modulation signal to a second device at a first frequency point; after receiving the frequency-modulated signal sent by the first device, the second device modulates a data signal on the frequency-modulated signal in a backscattering form, shifts the data signal to a second frequency point, and reflects the modulated signal to the first device; and the first device receives and processes the modulated signal reflected by the second device at the second frequency point so as to obtain second device data. According to the method, low-power-consumption long-distance communication between equipment is realized by utilizing the frequency modulation signal and the backscattering principle, the reflected signal is demodulated at a signal-to-noise ratio lower than that of a conventional modulation scheme, the implementation scheme is simple, th