Sona O. Kundukulam

Compact arrow shaped antenna with embedded rectangular slot for dual frequency dual polarisation operation

A compact arrow shaped microstrip antenna with a rectangular slot is proposed. By embedding a rectangular slot in the patch an additional resonance frequency having opposite polarization compared to the TM/sub 10/ mode is generated This new frequency is much lower than the TM/sub 01/ mode frequency of the patch without a slot. The ratio between the two resonant frequencies can be tuned in a wide range by changing the slot length. These two orthogonal modes can also be combined to achieve circularly polarized radiation. The antenna offers an area reduction /spl sim/75% compared to a rectangular patch antenna designed for the same frequency.

A circular-sided compact microstrip antenna

A microstrip patch with considerable reduction in antenna size is presented. The proposed design uses curved edges so as to increase the effective resonating length. An area reduction of /spl sim/80% compared to a standard rectangular patch is obtained without much reduction in gain. Simple formulae are suggested for calculating the resonant frequency of the new geometry, and its validity is established by experimental results.