Study on the reader baseband receiver structure for the demodulation of subcarrier signal in a passive RFID environment

In this article, we present a subcarrier demodulation structure to eliminate an undesirable DC‐offset phenomenon, which may appear in the baseband of the reader receiver under passive radio frequency identification environment.To achieve the requirement, the primary feature of the proposed demodulation structure is to reconstruct the signal corrupted by the DC‐offset phenomenon by creating peak signals from the corrupted signal. In the case of the Miller subcarrier signal, the phase inversion information in the symbol duration is used for generating the peak signal. It is shown that the proposed method can successfully detect valid data from the received signal, even when the received baseband signal is distorted by the DC‐offset phenomenon. In addition, the performance of the proposed method is slightly better than or comparable to that of the well‐known‐matched filter‐type baseband receiver in the band‐limited channel environments. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1264–1272, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25995