Frequency-Spectra-Based High Coding Capacity Chipless RFID Using an UWB-IR Approach

Area of Science:

• Electrical Engineering
• Electromagnetics
• Radio Frequency Identification Technology

Background:

• Chipless RFID tags offer a cost-effective alternative to traditional RFID systems.
• Accurate prediction of resonant characteristics is crucial for reliable chipless tag performance.
• Existing methods often require calibration tags and are sensitive to tag orientation.

Purpose of the Study:

• To propose a novel methodology for reliably predicting the resonant characteristics of multipatch backscatter-based RFID chipless tags.
• To differentiate between informative and non-informative components of backscattered signals.
• To develop an orientation-independent and calibration-free prediction technique.

Main Methods:

• Utilizing an ultra-wideband impulse radio (UWB-IR) reader to interrogate the chipless tag with a UWB pulse.
• Analyzing the backscattered signal in the time domain to identify structural and antenna modes.
• Evaluating the spectral quality of different backscatter components.
• Validating simulation findings with experimental measurements using a 6-bit multipatch chipless RFID tag.

Main Results:

• The antenna-mode backscatter component was identified as carrying essential information for tag identification.
• The structural-mode backscatter component was found to be devoid of tag-specific information.
• The proposed technique demonstrated successful prediction of resonant characteristics without the need for calibration tags.
• Experimental validation confirmed the simulation results in an anechoic chamber.

Conclusions:

• The novel methodology reliably predicts resonant characteristics of multipatch chipless RFID tags.
• The technique effectively distinguishes informative antenna-mode signals from non-informative structural-mode signals.
• The developed method is calibration-free and allows for free orientation of tags relative to the reader, enhancing practical applicability.