Demo: UE Assisted Ambient IoT in LTE Downlink, in real-time and open source

Abstract

Ambient power enabled Internet of Things a.k.a. Ambient IoT is a novel concept connecting battery-free energy autonomous devices to the Internet. In this paper, we demonstrate the feasibility of using the channel estimator at the user equipment (UE) as a receiver for backscatter signals in LTE downlink. Our real-time demonstrator system consists of signal generator that mimics the operation of a base station (BS), a backscatter device (BD) modulating the incidence signal, and a software defined radio receiver that plays the role of the user equipment. The UE channel estimator and BD demodulation software is implemented with C++ and Python, respectively and made open source. Our results indicate that UE can demodulate the BD signal with bit error less than 10-3 when the downlink signal-to-noise ratio is larger than 10 dB when the pathloss between the BD and UE is less than 13 dB.