摘要:Two novel multiband patch antennas operating at centimetre band are proposed for a novel orthogonal frequency division multiplexing (OFDM) based radio-frequency identification (RFID) reader. Here, the first one is a dual band antenna with centre frequencies of 7.30 GHz and 9.50 GHz, while the second one is a triple band antenna centred at 7.75 GHz, 9.70 GHz and 11.90 GHz. Both the patch antennas are designed with equal-width horizontal arms as radiating elements and a microstrip feeding line as the feeder. The antennas are moderately small sized with dimensions of 40.30 mm by 35.10 mm. Simulations with Computer Simulation Technology (CST) Microwave Studio tool indicate that competitive values of different antenna parameters are achieved when compared with centimetre band antennas described in the literature. With the use of MATLAB tool, the bit error rate (BER) performance of the multiband antennas are simulated for outdoor Rayleigh and Rician fading channels. Simulation results for the proposed two antennas indicate that for a given number of OFDM subcarriers, the larger the bandwidth of the signals received by the RFID reader, larger the BER degradation. These results have confirmed the usability of the designed antenna in commercial OFDM based RFID readers.
关键词:Bandwidth;Bit Error Rate (BER);centimetre- wave;multipath fading;Orthogonal Frequency Division Multiplexing (OFDM);patch antenna;Radio Frequency Identification (RFID)