An RF-ID Reader Using SAW Dispersive Delay Lines For Wideband Synchronisation

Abstract

RF-ID systems are susceptible to frequency interference from other communcation systems particularly when the RF-ID tags transmit on a fixed carrier frequency. The RF-ID systems are less vunerable to frequency interference when frequency diversity is used by the RF-ID system. This paper proposes an architecture for an RF-ID receiver which allows a number of active RF-ID tags with oscillators of low frequency stability to be accommodated within the same RF-ID cell. The synchronisation technique used by the receiver contains a carrier frequency estimator which has been designed using SAW dispersive delay lines. The carrier frequency estimator uses the spectral properties of the received signal to estimate the carrier frequency. The analytic and simulated performance of the carrier frequency estimator has been examined for two peak search algorithms.