Reconfigurable antenna for cognitive radio application using slot and parasitic patch

This paper presents an analysis of frequency reconfigurable micro strip patch antennas for multi-band, multimode wireless communication systems, incorporating Radio Frequency-PIN diodes as switches. Two configurations are discussed with double-band characteristics: a patch antenna with modifiable and reconfigurable switchable slots; and a rectangular patch with a electronically controllable parasitic patch element. The objective is to evaluate the feasibility of the active antenna to be used in cognitive radio applications and predict the functional performance of frequency reconfigurable antennas integrated as RF switching elements. These microstrip antennas were simulated with CAD tools and the obtained results show acceptable radiation performance. Each of the simulated microstrip antennas allow electronic tuning of the operating resonant frequency, while maintaining optimum input impedance match and stable radiation characteristics over the frequency band of interest.