Application-Adaptable Chipless RFID Tag: Design Methodology, Metrics, and Measurements

The field of chipless radio frequency identification (RFID) is growing due to cost-effectiveness, simplicity, and versatility of the technology. Typically, the chipless RFID tags use a single type of resonator in their design and are designed for a singular application. These design practices are limiting both in terms of versatility and practicality. This article builds on previous work and proposes a new application-adaptable tag design methodology. This methodology revolves around the use of combinations of multiple types of resonators in backscatter-based frequency-coded tag designs for the purpose of enhancing the versatility and utility of the chipless RFID technology. From this novel design methodology, an original tag design presented previously that achieves a high bit density of 27.54 bits/cm
²
is further analyzed and optimized for two applications. Furthermore, this article presents a method for associating tag response characteristics to tag geometry and develops new tag metrics that can be used more effectively to compare the merits of sensing-based tags. The measurements of the manufactured tags are also presented, and the associated measurement challenges are discussed.