Radiation properties of triplate-type tapered slot antenna and its array

A tapered slot antenna (TSA) has been investigated by many researchers, since the TSA has several advantages such as high gain, wide bandwidth and simple configuration. A TSA fed by a microstrip line or a coplanar waveguide shows a high cross-polarization characteristic because of the unwanted radiation from its feeding system. A triplate-type tapered slot antenna (T-TSA) has a low cross-polarization characteristic, since the T-TSA element is fed by a center conductor of the shielded triplate line to avoid the influence of such unwanted radiation. This paper presents a basic design technique of the T-TSA element and its array antenna.