Design and Simulation of Microstrip Patch Array Antenna for Polarization Diversity

Abstract

With the rapid growth of wireless communication, the antennas with polarization diversity performance are widely studied and adopted, especially using Microstrip patch antenna. In the urban or indoor environments, the radio wave will propagate through complicated re ections or scattering process.In order to reduce signal fading caused by multipath e ects, diversity techniques are applied to the antenna system at the receiving site. Such type of antenna is particularly suitable for mitigating fading in multi-path propagation environments. The proposed design of inset-fed microstrip patch array antenna work in the ISM band with 2.4 GHz center frequency. A design of the broadband dual-polarized mi- crostrip antennas is proposed by using inset feed technique but slant at desired ro- tation. Here, +45 and -45 rotation is provided to the patch geometry, which gives dual polarization. First, the design parameters for single element of rectangular patch antenna have been calculated from the transmission line model equation and extended the antenna design into the array geometry. Single element +45 and -45 ,+45 1 2 patch array, -45 1 2 patch array and 45 1 2 patch array geometry have been design and simulated using FR4 ( r=4.7) and RT/DUROID 5880 ( r=2.2). From the simulation results, it is found that the RT/DUROID 5880 has very low loss compare to FR4. Further to meet the high gain and directivity demand 45 1 4 and 45 2 2 patch array antenna has been design and simulated. Bandwidth is improvised by increasing height of the substrate, increasing substrate height of 6.35 mm, 9% band- width has been achieved at the operating frequency range.