Pseudo-doppler direction finding antenna adaption for RFID applications

摘要

We propose a method and a system which allows to define areas of coverage as well as find out the direction in which an RFID transponder is located. The solution features an artificially generated Doppler effect (aka pseudo-Doppler). The Doppler Effect is a change in the phase and frequency of a signal due to the relative change in the distance between the sender and receiver. In a first step, a phase difference determination between the phase of transmitted signal and the phase of received signal for each of the coupled antennas is provided. In a second step, a calculation of the receiving angle by comparison of the multiple phase differences determined in the first step is conducted.