Characteristics of stacked rectangular and triangular patch antennas for dual band applications

Multi-band antennas have applications in radars and communication systems. For their light-weight low-cost properties, stacked microstrip patch antennas have recently gained increasing support as dual frequency antennas. The paper presents a general technique for the theoretical determination of the input impedances and the radiation patterns of stacked microstrip patch antennas of arbitrary shapes. It then investigates various cases of stacked rectangular and triangular patch antennas. For these antennas, some approximations are introduced in the modelling technique in order to make it efficient on personal computer. The investigations on the stacked rectangular patch antenna focus on antennas with dissimilar substrates, non-aligned patches or unequal patch sizes. The effects of some radomes on the characteristics of the stacked rectangular patch antennas are also included. As far as the stacked triangular patch antenna is concerned, its analysis is presented and its performance is compared against that of the rectangular counterpart. Some experimental results are also reported