High Code Density and Humidity Sensor Chipless RFID Tag

Abstract

This article presents a low cost, miniaturize, flexible, high code density chipless sensor tag. The tag is designed on polyethylene terephthalate (PET) substrate with a compact size of 1cm radius operating in ultra-wideband, ranging from 3.5 to 16GHz. The overall structure and results have been significantly improved in comparison to the latest research. It has high code density of 6.92bits/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , regular geometry, larger sensitivity for the humidity of 60MHz/%RH variation, high magnitude frequency dips, angular stability up to 60°, high radar cross-section, low cost, and compact size are distinctive outcomes of the suggested sensor tag. It is simulated in computer simulation technology microwave studio (CST-MW). The tag can provide information about biomass locomotion, available weight in storage and combust. It has robustness, grind-bile, and combustible properties during combustion and pyrolysis process. This paper provides a pathway for biomass pellets tracking and humidity monitoring by using a battery-free chipless RFID sensor tag in real-time.