Antennas Currently there is large scope in wireless applications due to increased scalability and mobility. Users need these technologies to improve data accessing information from anywhere along with high data speed giving rise to 5G technology. Today’s recent growth increased by huge capacity, data rate and high throughput with single antenna system fulfilling the given requirement more likely to do multipath fading and had low data rate. The drawbacks can be overcome by the MIMO antenna in the wireless communication system.In this paper we designed a rectangular patch antenna with semicircle defective ground substrate which improves the efficiency and reduce interference. These might have wide range of applications in WLAN and WiMAX. This has an advantage of less interference using MIMO antenna. The proposed antenna will be working at frequency of 4-6GHZ (c-band) and frequency (x-band) applications mainly satellite and WiMAX applications.

Wireless technology is one of the main areas of research in the world of communication systems today and a study of communication systems is incomplete without an understanding of the operation and fabrication of antennas. A simple and compact printed ultra-wideband antenna with dual-band-notched characteristics is presented. The proposed antenna is composed of a rectangular patch and a modified ground plane. The rectangular patch is etched onto a lossy FR4 substrate. A circular ring strip parasitizes the rectangular patch embedded by a U-shaped slot. Two Inverted-L slits and a rectangular slit are embedded onto the ground plane. Some bandwidth enhancement and band notched techniques are applied in the antenna structure for broadening the bandwidth and generating notches. The simulated and measured results show that the proposed antenna offers a very wider bandwidth ranging from 3.04 to 17.30 GHz, defined by the return loss less than −10 dB, with dual-notched bands of 3.30–4.20 and 5.10–5.85 GHz covering the 3.3/3.7 GHz WiMAX, 3.7/4.2 GHz C-band, and 5.2/5.8 GHz wireless local area network systems.