Applications Of Genetic Algorithms To The Design Of Microstrip Antennas

In recent years, the demand for miniaturization, multiband and broadband antennas have been presented with rapid development for mobile communications. Therefor, the size of the antenna is required to be as small as possible. Microstrip antennas have several advantages over conventional monopole-like antenna for mobile bandsets. They are less prone to be damaged,compact in total size and aesthetic from the appearance point of view.This thesis presents an introduction and overview of advances in the design of both the compact and broadband microstrip antennas. The shorting-pin-loaded microstrip antenna and L-shape slots loaded antenna, E-shape antenna are studied and simulated by High Frequency Structure Simulator (HFSS) as well.Another part of work is the optimization of microstrip antenna by Genetic Algorithms(GA) combined with High Frequency Structure Simulator. HFSS is used to calculate the S11 parameter of the antenna and GA is applied to optimization of the antenna on the basis of S11.The mixed optimization program for GA and HFSS is investigated under the environment of Matlab. By utilizing this set of optimization program, several antennas including 2.4GHz PIFA,1.8GHz/2.4GHz PIFA with L slot, wideband E shape microstip antenna and two patch antennas with many windows cuts on them are designed. The final antennas we get at last have the desired S11 parameters we want. As to different antenna configurations, different coding methods and different fitness functions are adopted.