Design And Analysis Of Microstrip Antenna For 2.4 Ghz Applications

ABSTRACT

Communication systems require development of low cost, low profile and minimal weight. Microstrip antennas (MSA) are capable of maintaining high performance over a wide spectrum. Technological trends have focused much effort on the design of the microstrip patch antennas. In this study, square, circular and rectangular patches were designed and analyzed using two different substrates. High Frequency Structure Simulator (HFSS) software was used to simulate, model and analyze the MSAs. Simulation was done using FR4 substrate on square, rectangular and circular patches at a frequency of 2.4 GHz. At the same frequency, RT Duroid 5880 was used in the simulation of the square, circular and rectangular patches. The thickness of the substrate was kept constant at 1.6 mm. Simulation results that include bandwidth, efficiency, return loss curves and radiation patterns of all the MSAs from the software were compared. The resonant frequency for all simulated microstrip antenna was 2.4 GHz. A circular microstrip antenna on RT Duroid 5880 had the highest efficiency of 97.012% and front to back ratio of 77.74. The same MSA also had the highest realized gain hence it was considered for fabrication. Fabrication was done through a process of photolithography and wet etching on a printed circuit board using parameters of the results that were optimized. Testing of the fabricated MSA was done using scalar network analyzer. The resonant frequency of the fabricated microstrip antenna was 2.3966 GHz and the return loss was -24.965 dB. The measured data was validated with the simulated data. The measured data from the fabricated MSA deviated slightly from the simulated data. It was ascertained that the MSA can work efficiently at 2.4 GHz. Other than the shapes used in the research different shapes can be tried for example elliptical quarter circle can be studied. Substrates with lower directivity can be used which can give higher gain. To reduce the size of microstrip antenna a substrate with high dielectric constant like silicon can be tried. Array of antenna patches of these shapes should also be studied because they produce the higher overall gain.