Self-interference noise limitations of RFID readers

In this contribution we compute the read range limits of RFID readers also modelling the often ignored self-interference and leakage cancellation effects. The forward link limit is defined by the sensitivity of the tag, while the reverse link limit depends on the ability of the reader to decode the tag message. We will express the reverse link limit and the receiver Signal to Noise Ratio (SNR), whose dominating expression is the self-interference noise. Further, we will introduce two Figures Of Merits (FOMs) relevant for the reverse link limit. In a broad range of these FOMs, the receiver SNR is independent of the transmit power and reader noise figure. Further, we calculate the average suppression gain of leakage cancellers which enables us to upper-bound the noise effective cancellation gain which directly relates with the reverse link limit.