Ambient Backscatter Communication in LTE Uplink Sounding Reference Signal

TL;DR

This paper proposes an ambient backscatter communication scheme integrated into LTE uplink, enabling low-power AIoT data transmission with validated theoretical analysis and practical prototype experiments.

Contribution

It introduces a novel AmBC method leveraging LTE uplink channel estimation, with detailed error analysis and a working prototype demonstrating feasibility.

Findings

Achieves BER of around 10^{-2} within four wavelengths

Theoretical error probability matches Monte Carlo simulations

Prototype confirms practical viability of the approach

Abstract

Ambient Internet of Things (AIoT), recently standardized by the 3rd Generation Partnership Project (3GPP), demands a low-power wide-area communication solution that operates several orders of magnitude below the power requirements of existing 3GPP specifications. Ambient backscatter communication (AmBC) is considered as a competitive potential technique by harvesting energy from the ambient RF signal. This paper considers a symbiotic AmBC into Long Term Evolution (LTE) cellular system uplink. Leveraging by LTE uplink channel estimation ability, AIoT conveys its own message to Base Station (BS) by modulating backscatter path. We explore the detector design, analyze the error performance of the proposed scheme, provide exact expression and its Guassian approximation for the error probability. We corroborate the receiver error performance by Monte Carlo simulation. Analysis of communication range reveals AmBC achieves a reasonable BER of order of magnitude $10^{-2}$ within four times wavelength reading distance. In addition, a AmBC prototype in LTE uplink confirms the its feasibility. The over-the-air experiment results validate theoretical analysis. Hence, the proposed AmBC approach enables AIoT deployment with minimal changes to the LTE system.