Energy Efficiency Performance Analysis of Single and Multi-Receive Antenna Backscatter Communication System

Ambient backscatter communication (AmBSC) via ambient energy harvesting passive tags is helpful in the passive internet of things (IoT). Since energy is a limited resource, energy-efficient BSC is essential in passive IoT and could provide long-term profitability. We first consider a simple three-node BSC system set up with a single tag node. In it, all nodes have a single transceiving antenna. We analyze the BSC link's energy efficiency performance over the frequency-flat Rayleigh fading channels for this model. Specifically, we derive analytical expressions for average energy efficiency for the ambient BSC. We then consider an ambient BSC system having a receiver with multiple antennas with antenna selection. For this complex BSC system model, we analyze and evaluate average energy efficiency. We validate derived analytical results using Monte-Carlo simulations. In addition to exact energy efficiency, we also derive its upper bound. The detailed analysis and new insightful results that we present are helpful to design and optimize ambient BSC systems in terms of energy efficiency.