Using monopole elements to increase pattern versatility in television slot antennas

The Tau shaped monopole element can alter and improve the antenna´s radiation pattern without affecting mutual coupling between elements or the impedance bandwidth, in cylindrical slot television antennas. It is applicable to omnidirectional, peanut, trilobe, and cardioid arrays. Under the vertical Tau configuration, more control is afforded to the H-pol slot pattern and a vertically polarized pattern component is generated. The dimensions of the elements control the amplitude, phase and pattern width. Use of this monopole shape in different arrays and in cylindrical and rectangular waveguide structures as well as coaxial structures provides great pattern versatility. Examples are given with predicted and measured results