(An) energy efficient BFSK transmitter for UHF active RFID reader using 2-port dual polarized antenna

Abstract

In this paper, An energy efficient transmitter scheme for a RFID reader is presented. Conventionally, a RFID tag uses a linear polarized antenna, and a reader uses a circular polarized antenna. In this circumstance, the reader can read tags regardless of their orientation, but there is always 3dB loss of the power of the signal sent from the reader. To overcome this problem, we use a 2-port dual polarized antenna for a reader so that the reader can send linear polarized signal. Also, we propose to divide reading operation into 4 steps to cover every orientation of tags. With this operation, an energy required to read tags can be reduced by 0.6 times compared to the conventional way. The desired operation is verified through simulation.