Radar cross-section and electric field analysis of backscattering elements of chipless RFID tag

Radio identification (RFID) systems based on chipless tags, outperforms traditional RFID systems in terms of costs, and the actual challenge in the former systems is to improve the quantity of bits written in a tag. Actually, the main information encoding technique is based on the generation of a particular signature in the spectrum of the backscattered signal. Chipless tags based spectral signature encode data using resonant structures, to work like band reject filters, designed to resonate at certain frequencies. Information is written as a combination of nulls in the frequency domain. Based in the idea of simultaneously use the horizontal and vertical polarization of an antenna, in this paper we analyze the radar cross-section (RCS) and electric field of elements of chipless RFID tags based on biostatic RCS. Using electromagnetic simulation software for electric field and RCS analysis, it was observed that it is possible to write data to improve the number of bits using two simultaneous polarizations.