Fast Algorithm for Leaking Carrier Canceller Adjustment

RFID readers for passive tags generally suffer from self-interference. The transmitter of the RFID reader is also in operation during receive periods to power the tag and enable backscatter modulation. The state-of-the-art solution employs a leaking carrier canceller, which needs to be adjusted. The proposed fast algorithm provides a starting point for conventional gradient based approaches, which already improves isolation by 7.2 dB at least. It is based on three scalar measurements, and does not demand for special hardware. The algorithm was tested on our RFID test bed and experiments show a significant decrease of steps necessary to reach the final leaking carrier canceller setting.