Abstract:
A micro strip antenna with multiple parasitic patches for Cognitive Radio Network applications is presented to enhance the bandwidth. Multiple resonances are used for the design of antenna, with a view to broaden bandwidth. Microstrip antennas are widely used in many applications due to their low profile, low cost and ease of fabrication .In some applications it is required to have a dual band characteristics instead of single band. These characteristics can be obtained by coupling multiple radiating elements. The proposed antenna is designed and efficiently operates at 1 GHZ and 3 GHZ resonant frequencies for Cognitive radio applications; the antenna and design with pre-determined and calculated parameters by using specific equations. The desired resonant frequencies and dielectric constant of the substrate are known or selected initially based on the applications which this antenna will be used in its (WLAN).After that the calculated or selected dimensions and parameters were simulated by CST simulator. Throughput, return loss, VSWR, input impedance, Gain and radiation pattern have been improved, a model of antenna has been fabricated and its radiation patterns, return losses were achieved which shows fine consistency with simulated results then these theoretical results were compared with the desired results, The simulation results were evaluated in term of and the dimensions are optimized to achieve the exact operating frequencies.
