Simulation and design of a chipless passive RFID tag

RFID is an object identification and tracking technology worth several billion dollars today. Chipless technology doesn't require communication protocols and IC, making it cheaper. Passive RFID Tags use backscattering technique to send information to the Reader. In this paper, we present a passive RFID Tag based on Ultra-wide band technology. The chipless RFID tag modeled uses passive elements, namely antennas and transmission lines in different architectural orders by varying the lengths and the number of the transmission lines. The unique identities of the tags are characterized by the number and the lengths of the transmission lines and hence a large number of tags can be manufactured economically with a finite number of transmission lines. The technology involves transmission of nanosecond duration pulses which enables high precision time of arrival (TOA) estimation of signal. The software tool used to simulate this system is Linux based open source software development toolkit called GNURadio. It has a predefined set of signal processing blocks and has the provision to code user defined blocks and enables us to represent the RFID system using standard programming languages namely C++ and Python.