International Journal of Computer Applications (0975 – 8887) Volume 85 – No 17, January 2014 31 Subsequently 90 0 Repositioned Triple E Shaped Microstrip Patch Antenna Design for Multiband Application Razin Ahmed Islamic University of Technology (IUT) Gazipur- 1704 Shahriar Rahman American International University Bangladesh (AIUB) Banani, Dhaka Tanver Ahmed American International University-Bangladesh (AIUB) Banani, Dhaka ABSTRACT Wireless communication system and technology opened a new horizon around the world through electromagnetic spectrum. As the technology evolving demand for high and continuous data connectivity in satellite and radar communication has been growing faster, researchers are facing challenges to integrate cost efficient, miniature size and multiband operating antenna in wireless devices. Microstrip Patch Antenna can fulfill all requirements but there is always a trade-off between the performance and design. In this paper modified slots with reconfigured E shapes Microstrip Patch antenna is designed and analyzed for multiband wireless application. The probe feeding technique and design structure provides the antenna to operate in five different frequencies. The antenna resonates at 7.81 GHz in C band, 8.31 GHz, 9.65 GHz and 11.86 GHz in X band, and 13.2GHz and 14.79 GHz in Ku band with return loss of -19.26 dB, -24.82 dB, -13.18 dB, -33.61 dB, -12.46 dB and -12.04 dB respectively of proposed antenna have been examined and discussed. Keywords Microstrip Patch Antenna (MPA), Rectangular Microstrip Patch Antenna (RMPA), Electromagnetic (EM), 1. INTRODUCTION The contemporary theory of electromagnetic wave properties has come from one of the greatest pioneer in history Science: James Clerk Maxwell. His famous equations enabled us to take leaps in the field of electromagnetism resulting wireless technology to grow exponentially over decades to come. Numerous ranges of frequency band for diverse communication system are present in the modern time and are allocated to use in various purposes. Therefore integration of multiband‟ in wireless communication devices became more dependable in most social, scientific, commercial and other contexts. To enable multiband operation, antenna should have the option to transmit and receive multiple frequencies. Among all the different types of antennas [1 & 2], Microstrip Patch Antenna (MPA) has become well accepted around the world. The fundamental structure is made up of a conducting patch of any non-planar or planar geometry on one side of a dielectric substrate and a ground plane on other side [3]. It has higher multilateral lead for planer profile, capacity to function in microwave frequency range, economic to manufacture and simple to construct in integrated circuit technology when contrasted with conventional antenna. Due to their light weight, low volume and low fabrication cost, they can be produced in huge quantities [4-6]. However beside all advantages of MPA there are disadvantages also such as low efficiency, single frequency operation and narrow impendence bandwidth. In recent years, several scientists from industries and universities are investigating and have come up with several multiband antenna techniques, among them are loading the patch with shorting pins [7-9], using two feeding ports [10], loading slits [11], using stacked patches [12-15], PIN diodes, switches and varactor diodes have been used. Major shortcoming of the design is the requirement for controlling turn ON/OFF switch for reconfigurable frequency operations [16-18] using slots in the patch [19 & 20]. Many structures like Square Slot, U-Slot, T-Slot, V-Slot and many other shapes are incorporated into the patch of antenna. Now, to improve impedance bandwidth some techniques may be applied such as increasing the substrate thickness [21], covering the patch by additional dielectric layers [22 & 23], introducing parasitic element either in coplanar or in multilayer configuration [24], and performing slots in radiator patch [25]. The slots help to perturb the surface current path on the patch that generates local inductive effect which is responsible for multiband operation. Among all the approach slot technique is very promising because it can provide excellent bandwidth improvement and maintain a single-layer radiating structure with multiband feature. From above literature authors are motivated to design an MPA which operates in multiband application. 2. ANTENNA DESIGN The antenna configuration has been made on the conventional Rectangular Microstrip Patch Antenna (RMPA). The whole design of the proposed antenna is developed in IE3D EM simulator software using low cost FR4 substrate material of thickness h=1.6 mm and permittivity r  = 4.31. The antenna consists of radiating patch, ground plane and dielectric substrate between them. Figure 1 represents the basic structure of proposed antenna. The initial parameters are determined from the following equation [26]. 1 2 2   r r f o W   (1) 2 1 12 1 2 1 2 1             W h r r eff    (2)                       8 . 0 258 . 0 264 . 0 3 . 0 421 . 0 h W h W h L eff eff   (3)