A low gain and narrow bandwidth of single microstrip antenna element will not accomplish a good performance in wide applications. In this paper, the design and simulation of microstrip antenna with an arrays for gain enhancement were made. The suggested design is made up of four elements of microstrip antenna in rectangle shape which associated with an array pattern. The antenna is operating at 5.8 GHz. Each element is created with truncated-edge of rectangular shape which had an inclined slot on each patch which realize circular polarized capability. The design of the 2×1 and 2×2 of rectangular microstrip array antenna was implemented from the designed of single rectangular element of patch antenna as the basic building element. The designed 2×1 and 2×2 array were fed by microstrip transimmision line which applied a technique of quater wave impedance matching. The antenna design was etched on Rogers RT 5880 substrate which have dielectric constant of 2.2 and have a thickness of 1.53. All the designed structure were simulated in CST software. The proposed antenna finally will compared between both 2×1 and 2×2 design in terms of gain, axial ratio and reflection coefficient. The simulated antennas resonated exactly at the desired frequency of 5.8 GHz with reflection coefficient below than -10 dB which indicates good antenna designs. The 2×1 and 2×2 arrays obtained gain of 10.8 dB to 13.3 dB respectively. The results show that the proposed designed have an improved gain performance over the single patch antenna.
