Monostatic Backscatter System with Multi-Tag to Reader Communication

In this work, we consider a monostatic backscatter communication system employing successive interference cancellation where a reader simultaneously serves multiple backscatter tags or nodes (BNs). To minimise collisions, each BN randomly chooses a sub-frame to backscatter the continuous wave signal transmitted by the reader only if its received power is above a backscatter threshold. The reader then employs successive interference cancellation technique to resolve the resulting smaller number of collisions. Using stochastic geometry, we derive an approximate yet accurate expression for the average number of successfully decoded BNs. Our derived expression allows the system performance to be predicted numerically and also allows us to determine the backscatter threshold to maximize the system performance.