Indoor Backscattering Communication by Using Commercial LTE Pilots

The Long Term Evolution (LTE) is a promising can-didate to be used as a signal source in the Ambient Backscatter Communications (AmBC). LTE provides ubiquitous coverage, and LTE User Equipment (UE), such as mobile phone, can be used as the reader of a Backscatter Device (BD) signal with small firmware modifications. In this paper we measure a BD signal indoor coverage with commercial LTE base station as the illuminating ambient signal. The reader is synchronized to the LTE BS and estimates the BD signal from the LTE signal pilots. The BD is fully passive powered by a solar panel. The BD locations are distributed spatially along the corridor and for each BD location we measure the AmBC reader signal Bit Error Ratio (BER). The signal is uncoded. For each BD location the BER is measured from different directions with respect to the BD position. The measurement results show that along the corridor in most location, the observed BER is in order one percent. The results shed light on the feasibility of applications where the UE is in close proximity to the BD.