Impact of the Polarization over the Read Range in Chipless RFID

This paper presents a fair comparison between the read range of chipless RFID in co-polarization and cross-polarization in real environments. This comparison is a direct consequence of the bound on the read range for the chipless technology presented in [1]. The approach is based on an analytical model and validated by simulations and measurements. Results are mainly function of the considered residual environment. In static environments (such as anechoic chambers), co-polarization offers the highest read range due to the higher Radar Cross-Section (RCS) of the resonators with identical residual environments. However in dynamic environments (which include all real environments), cross-polarization is more robust since, even if resonators RCS is 6 dB lower than co-polarized tags, the associated residual environment is 10 dB lower. Thus read range in cross-polarization outperforms by a factor of 26% the one obtained in co-polarization in almost all real applications.