A U slotted H-shaped Micro strip antenna with capacitive feed for broadband application

A H-shaped Microstrip patch antenna with u slot and capacitive feed is presented here. To overcome the various problems in the feeding, a capacitive feeding scheme has used which consist of a radiator patch and a small coplanar feed strip very near to it. The design of antenna incorporates the capacitive feed strip which is fed by a coaxial probe by using equivalent approach. Two slots are used in the radiating patch of the proposed microstrip antenna to increase fringing field results the improved bandwidth. U slot is made at the center of radiating patch to increase the radiating edges which will help in increasing the bandwidth. A constant radiation pattern with improved VSWR bandwidth of nearly 46% and return loss up to -20 dB, for an operating frequency of 5.1 GHz can be easily achieved by using this simple geometry. The effects of key design parameters such as air gap between the substrate and the ground plane, the separation distance between the radiator patch and feed strip, probe diameter and dimensions of the feed strip on the performance of the antenna are studied and discussed.