Wideband gap-coupled suspended rectangular microstrip antenna

In this paper, we present the bandwidth enhancement of microstrip antenna using microstripline feed, suspended and gap-coupled configuration. First, the bandwidth of suspended microstrip antenna (SRMSA) is enhanced by gap coupling the parasitic patch to the radiating edge of fed patch of the antenna. Using this technique, an optimum bandwidth of 22.24% is obtained. Later, two parasitic patches are gap-coupled to the non-radiating edges of fed patch of SRMSA. This enhances the bandwidth of antenna and a maximum bandwidth of 53.25% is obtained. The air gap is kept same in both cases. The enhancement of impedance bandwidth is achieved without affecting the nature of broadside radiation characteristics. The proposed antenna may find applications in radar communications. Design concept of the proposed antennas is described and their experimental results are discussed.