Implementation of Low-Cost Multi-Antenna AmBC Receivers.

We implement several low-cost ambient backscatter communication (AmBC) receivers for the first time in practice. Multi-antenna AmBC receivers have been actively investigated theoretically. Practical implementations face a challenge as low-cost antennas are prone to suffer from wideband effect and/or hardware impairments and propagation environment is complicated. For a successful implementation, we propose a signal processing method which avoid the wideband signal but extracts the reference signal which is narrowband. We evaluate the method using the data measured in a complicated environment. Measurement results show that the proposed signal processing tackles the above issues and gives acceptable bit-error-rate (BER) performance of AmBC systems. The implementation of low-cost multi-antenna AmBC receivers paves the way for realizing ubiquitous green communication systems.