AbstractsBiology & Animal Science

Microstrip antennas have been in limelight ever since their lineage in early sixties. These antennas are in great demand because of their many advantages over the conventional antennas which makes them suitable for a wide variety of applications. The microstrip antennas have features like small size, low cost, conformability and high performance over a wide spectrum of frequencies. These features make them suitable for mobile communication, satellite communication, phased arrays, Global Positioning System and radar applications. However, a major drawback of these antennas is low bandwidth. Various techniques have been proposed by researchers to enhance the bandwidth of these antennas. newlineThe research presented in this thesis principally investigates the influence of defected ground structure (DGS) on the bandwidth of microstrip antennas. The effect of DGS on the antenna gain, directivity, side lobe level and cross polar radiations is also investigated. Defected ground structure is one of the effective methods to enhance the bandwidth of microstrip antennas. Various types of DGS are introduced to enhance the bandwidth of circular patch antenna, circular ring antenna and stacked antenna respectively.%%%