Characteristics of a large bandwidth rectangular microstrip-fed inserted triangular patch in a circular slot antenna

The characteristics of a rectangular microstrip-fed triangular patch in a circular slot antenna have been analyzed using the finite-difference time domain (FDTD) method. The impedance and bandwidth of the proposed antenna greatly depend on the design parameters. The normalized radiation resistance values of a triangular patch in a circular slot antenna varies less in the usable frequency band than for a square, or a circular patch. It means that the antenna shows a wider bandwidth than the other types, and although the use of a high relative permittivity (epsilon(r) = 4.3) substrate usually restricts the operating bandwidth, the radiation resistance also has a low value. The measured bandwidth is approximately 96.3 percent for a SWR less than or equal to 2.0.