Non-Coherent Detection and Bit Error Rate for an Ambient Backscatter Link in Time-Selective Fading

This paper focuses on the non-coherent detection in ambient backscatter communication, which is highly appealing for systems where trade-off between signaling overhead and actual data transmission very critical. Modeling time-selective fading channel as a first-order autoregressive (AR) process, we propose new receiver architecture based direct averaging of received signal samples detection, departs significantly from energy averaging-based receivers considered literature. For proposed setup, characterize exact asymptotic bit error rate (BER) both single-antenna (SA) multi-antenna (MA) receivers, demonstrate robustness to timing errors. Our results that while direct-link (DL) interference power source leads BER floor SA receiver, MA can remove this by estimating angle arrival (AoA) DL. The analysis further quantifies effect improved angular resolution function number receive antennas. A key intermediate result our derivation concentration general sum sequence central conditional distributions signal.