Signal Detection Scheme in Ambient Backscatter System With Multiple Antennas

The ambient backscatter technique is a communication technology that uses ambient radio frequency signals to enable battery-free devices to communicate with other device. This paper proposes the ambient backscatter technique using multiple antennas. Since the tag only plays a role of reflecting signals, a signal is transmitted with a power allocation in the case of multiple antennas. At the receiving end, the higher power signal is detected first via the received signal. Next, signal from other antenna is detected by using the first detected signal. Since the backscatter technique generally uses energy detection, it has a low data rate using a single antenna. The proposed method can obtain a higher data rate than conventional methods by using multiple antennas. Also, it can be usefully used for the Internet of Things system, which requires high data rate through the proposed backscatter method.