Abstract: In this paper a microstrip rectangular patch antenna using different permittivity of duroid substrate is designed and analysed. The antenna is designed at a resonant frequency of 5.8 GHz. The dielectric substrate used for antenna designed is duroid having a dielectric constant of 2.2. It is observed that the gain of the designed antenna increases on increasing the relative permittivity of the duroid substrate and decreases on increasing the permittivity of the substrate. The return loss of the designed antenna also decreases on reducing the permittivity of the substrate. Voltage standing wave ratio for the design antenna for different permittivity of the substrate is below 2.The designed antenna is energized using microstrip line feeding technique. The different characteristics of the antenna such as gain, bandwidth, return loss, directivity and VSWR is carried out for different values of the permittivity .The antenna is designed and analysed with the software High Frequency Structure Simulator (HFSS).

Keywords: Microstrip antenna, VSWR, Bandwidth, High Frequency structure simulator.