A Miniaturized Frequency Reconfigurable Patch Antenna for IoT Applications

This work presents a novel frequency reconfigurable patch antenna design for Internet of Things (IoT) applications. The proposed antenna structure has hexagonal patch element. Frequency reconfiguration is realized by employing a varactor diode in the microstrip feedline. The miniaturization in the proposed antenna design is obtained by incorporating defected ground structure (DGS) in the ground plane along with reactive loading employing varactor diode. These miniaturization techniques result in size reduction with an overall antenna size of 40 × 40 mm 2 . The results achieved show that the presented antenna produces frequency reconfigurable feature with continuous tunability from 1.4 to 2.9 GHz, thus covering several wireless communication technologies like WiFi, Bluetooth, ZigBee, GPS, and other 2G/3G/4G cellular standards. The proposed antenna has stable gain patterns with maximum measured gain of 2.4 dBi. To prove the concept, proposed antenna is fabricated and measured. The simulations and measurements exhibit good agreement. The antenna design is compact, simple, planar and low-profile making it suitable for wireless handheld applications including IoT.