Platform-Tolerant Nested-Slot RFID Tag Antenna Based on Jigsaw-Shaped Metasurface

A novel low-profile (<0.005 λ) jigsaw-shaped metasurface for platform-tolerant nested-slot radio frequency identification (RFID) tag antenna is proposed in this letter. It consists of a 4 × 4 array of rippled-edged patch units with a central through-via. Compared with the widely used patch-unit artificial magnetic conductor structure, the proposed jigsaw-shaped metasurface is proved to suppress the surface waves effectively and reflect the electromagnetic waves in phase in the industrial scientific medical band of 902–928 MHz, therefore, it could improve the frequency and radiation stability of the nested slot RFID tag antenna on different platforms, and enhance the radiation performance of the tag antenna. The prototype of the metasurface was fabricated and measured as an interlayer of the nested-slot RFID tag and different platforms. The measured operation frequency band remains stable, and the measured reading range has a range deviation of less than 8.7% on different platforms.