A digitally tuned reconfigurable patch antenna for IoT devices

In this paper, a reconfigurable patch antenna design operating at 868MHz for Low Power Wide Area Network (LoRa), 1.58 GHz for Global Positioning System (GPS) and 2.4 GHz for Bluetooth is presented. The design is reconfigurable thanks to the integration of a digitally tunable capacitor (DTC). The DTC capacitance changes according to a 5 bits' sequence command. A microcontroller is used to assign the required sequence, and thus leading to frequency reconfiguration. The antenna is a circular patch with a gain that varies from 0.2 dB to 6 dB based on the desired frequency of operation and the reconfiguration state. The antenna is designed for internet of things (IoT) applications.