Improvement of the read range of a chipless RFID for MPSK UWB system in outdoor and farm NLOS environment using receiver diversity with maximal ratio combining

An analytic approach is presented to evaluate the Bit Error Rate (BER) and read range of a UWB chipless RFID network using diversity technique at the reader receiver for Rayleigh fading over the channels. The analysis is carried out with multiresonator based chipless RFID tags for a UWB system of frequency range from 3GHz - 6GHz and bandwidth of 500MHz in an outdoor and farm non line of sight (NLOS) environment. SISO configuration is used to communicate from reader to tag and SIMO configuration is used to communicate from tag to reader. Maximal ratio combining technique is used in the reader for diversity reception of the tag. BPSK, QPSK and M-ary PSK are considered with coherent demodulation to evaluate the BER performance and a read range of 548.00m at the BER of 10^-06 could be achieved. The analyzed approach not only gives an improved result compared to the previous research works but also gives a clear insight regarding the interrelationship between BER, detection ranges, reader received power, number of receiving antenna and read range improvement.