Exploring Polymer Substrate-based Frequency Reconfigurable Antenna for Cognitive Radio Applications: Design and Analysis

Cognitive Radio (CR) provides an intelligent solution to address spectrum scarcity in wireless communication systems. This research work deals with the designing, simulation, and fabrication of a frequency reconfigurable microstrip patch antenna for Cognitive Radio Networks (CRN). The frequency reconfigurability of this antenna is established using a Polyvinyl Alcohol (PVA) and Activated Carbon (AC) composite substrate exhibiting flexibility and possessing a dielectric constant of 3.2. To achieve frequency reconfigurability, two PIN diodes are integrated in the design for smooth frequency switching. The designed antenna has a novel circular-rhombus shape and attains resonance at 6 GHz. Performance results indicate a return loss of -27 dB, a gain of 4.6 dB, and a VSWR of 1.07. A VNA is used to measure the fabricated antenna without PIN diodes, showing strong agreement with the simulation results. This design points out its potential for efficient, cost-effective, and flexible communication systems in dynamic spectrum environments.