A rectangle semicircular antenna is developed for mobile communication systems. The antenna is made up of a pair of folded semicircular dipoles which are coupling fed by a micro strip line. The planar antenna achieves a bandwidth of 53% for dB, covering the frequency range 1.25–2.1 GHz for mobile applications. The antenna gain of the broadband antenna element is about 7dBi. Gain and bandwidth enhancement is achieved using fabry perot cavity between reflector and planar antenna. The FR4 dielecric is used which is low in cost, simple to fabricate and easily available, while presence of air between feed antenna and parasitic patches increases the efficiency of the structure. Effects of variation in various parameters like dimensions of feed, parasitic patches, feed point, inter-element spacing and reflector height are analyzed. By decreasing the reflector at 120mm the gain of about 7dBi is obtained. Various gain flattening techniques are also proposed in this project. The proposed antenna with modified dimensions and spacing between the elements is fabricated and tested..