Reducing Dynamic Range in Bistatic Backscatter Communication via Beamforming Design

TL;DR

This paper introduces a novel beamforming approach for bistatic backscatter communication systems to reduce direct link interference and enhance signal power, thereby improving performance for massive IoT deployments.

Contribution

The paper proposes a new transmit beamforming design that mitigates direct link interference and boosts backscatter device signal strength in bistatic backscatter communication systems.

Findings

Proposed beamforming reduces direct link interference compared to maximum-ratio transmission.

The design improves the probability of error performance in backscatter communication.

Simulation results confirm the superiority of the proposed method over benchmark scenarios.

Abstract

Considering the exponential growth of Internet-of-Things devices and the goals toward sustainable networks, the complexity should be focused on the infrastructure side. For a massive number of passive devices, backscatter communication (BC) is a promising technology that reduces cost and increases energy efficiency by enabling transmitting information by backscattering radio frequency signals. Two main limitations that restrict the performance of BC are the round-trip path loss effect and the direct link interference (DLI) from the carrier emitter (CE). To circumvent this, we propose a novel transmit beamforming design for a multiple antenna bistatic BC (BiBC) system that realizes both purposes: mitigation of the DLI and increasing the power towards the backscatter device (BD). Additionally, we provide a detector design and the performance is evaluated in terms of the probability of error, for which we also provide a closed-form expression. Finally, simulation results show the superiority of the proposed beamforming design in decreasing DLI over a benchmark scenario that considers maximum-ratio transmission.