Relay selection scheme for cooperative backscatter communications networks

Abstract

Backscatter communications has become an emerging alternative to replace conventional radio frequency (RF) communications, especially for the internet of things (IoT) networks. Due to its low power and low complexity operations, it is well suited for the implementation of IoT in next generation communications networks. Since backscatter devices operate on the principle of reflecting RF signals, the transmission range of such devices is very small. Relaying has been commonly adopted for extending the communication range of distant devices. An efficient relay selection scheme can significantly improve the signal to noise ratio at the base station. In this paper, we propose a relay selection scheme for an IoT network, where backscatter devices relay information to the base station. The proposed scheme enables out-of-coverage devices to communicate with the base station via backscatter relay devices. We also explain the procedure for obtaining the channel state information for efficient beamforming of signals at the base station in order to achieve improved data rates. Simulation results show that acquiring accurate channel state information can significantly improves the overall data rates of the proposed backscatter relay network. We also show the effect of various system parameters on overall system performance.