Extraction of Aspect-Independent Parameters Using Spectrogram Method for Chipless Frequency-Coded RFID

In this paper, a novel method for the extraction of aspect-independent parameters (that are analogous to complex natural resonances) chipless radio frequency (RF) identification (RFID) tags is presented. This based on short-time Fourier transform (STFT). The concept proved by utilizing classical depolarizing tags. Owing proposed spectrogram approach, reading success rate RFID tag improved accurate (ID) quality factors. With single measurement (i.e., without empty measurement) in practical environment, performance characterized: 1) at various misalignments reader and tag. 2) distances mounted numerous objects. 3) displacements within 3D zone interrogation. technique computationally fast due inherent nature (FFT) STFT.