Signal Detection for Batteryless Backscatter Systems with Multiple-Antenna Tags

Ambient backscatter, one type of batteryless backscatter, is a new technology that utilizes environmental wireless signals to enable battery-free devices to communicate with each other. Most existing studies on ambient backscatter are based on the assumption of a single antenna at each tag. In this paper, we investigate signal detection in ambient backscatter communication systems with multiple-antenna tags. The use of multiple antennas results in multiple channel parameters between the tag and the reader, which constitutes the main challenge for signal detection because the tag has limited power and can transmit few training symbols. We show that traditional detection algorithms can not be directly applied into these Batteryless Backscatter systems with multiple-antenna tags. New detectors are to be designed for such systems, which is a good topic for future research.