Reconfigurable Wideband Monopole Radiator using Paper Substrate for Bluetooth/ISM Band Applications

Reconfigurable antennas are required to be upgraded with the extensive utilisation for wireless and Internet of Things (IoT) applications. This works deals with compact and cost-effective antenna design that operates in multiple frequencies by the use of switching circuits. These switching circuits are the PIN diodes connected between the main radiator, the inverse L-shaped radiator and a U-shaped radiator. The four switching states of PIN diodes i.e., "ON-ON", "ON-OFF", "OFF-ON" and "OFF-OFF" connect and disconnect the radiators to provide multi-band frequencies. The non-radiating capacitive element of 10pF is used between the microstrip-line and the main radiator for frequency tuning. The antenna is designed on low-cost paper substrate that makes it inexpensive for production and covers an overall area of 43mm x 40mm x 0.44mm. The antenna efficiently work for bluetooth services, 5G mobile band and ISM band over a frequency range of 1.6GHz to 3.5GHz. The antenna gain and efficiency are 1.1 and more than 80% in the desire band respectively. All the simulated results such as reflection coefficient, gain, radiation pattern and efficiency proves the antenna to be in a favourable concurrence.