Intelligent reflection surface auxiliary backscatter communication method and system

The invention discloses an intelligent reflection surface (RIS)-assisted backscatter communication method and system, and belongs to the technical field of wireless communication. The method comprises the following steps: 1) establishing an RIS auxiliary backscatter communication network model based on an actual phase shift model; 2) considering a receiving signal-to-noise ratio constraint, an energy collection constraint, a label reflection coefficient constraint and a phase shift amplitude constraint of an RIS reflection coefficient, and establishing a transmitting power optimization problem of a carrier transmitter (CE); and (3) performing transmitted beam forming by using a maximum ratio transmission (MRT) algorithm, and obtaining an optimal solution of RIS phase shift and a label reflection coefficient based on an alternating optimization (AO) algorithm. According to the method, the mapping relation between the RIS reflection coefficient amplitude and the phase shift is considered, the influence of the R