Engineering Commons^™

Linearly Tapered Slot Antenna, Luis Alberto Tumialan

Theses

Design procedure for Linearly Tapered Slot Antennas (LTSA) has been developed and implemented using High Frequency Structure Simulator (HFSS) code based on a finite-element analysis.

A CAD study of two variations of a LISA based on either a stripline or a microstrip feed has been carried out. Circular and radial stubs have been considered in these designs for an antenna operating at 10 Ghz. LTSA on a Duroid substrate fed by a stripline has been designed to operate with better than 12 dB return loss. Fabricated antenna was characterized and had even a wider response than the CAD design. Radiation …

Cad Study Of Linear Tapered Slot Antenna, Anthony W. Kwan

Theses

Linear Tapered Slot Antenna (LTSA) is an attractive candidate as a radiating element in frequency scanning arrays. LTSA element backed by a rectangular cavity had been investigated and is proven to posses various physical design parameters suitable to optimize its performance. This study is focused on the feed position variation to optimize the performance while maximum of the current density variation is maintained in the slot region. It was observed that if the stub base of the microstrip feed structure is located in the middle of the slot region, current maximum can be obtained within the slot region at the …

Radiation From A Tapered Dielectric Rod Antenna, Anil Prabhakar

Theses

The radiation fields from a cylindrical dielectric taper is studied. The numerical results of a theoretical model for a taper excited by the dominant HEn mode is compared with experimental measurements. A theoretical mode] for the next propa¬gating mode in the structure. the TE01 mode. is investigated and numerical results based on this proposed model are generated. The theoretical models are based upon the combination of the exact modal field solutions for a step profile cylindrical dielectric rod waveguide. local mode Hum-T. and the equivalence principle for the determination of equivalent current densities.

The far-zone radiation field is considered to …

Rigorous Te Solution To The Staircase Model Of The Dielectric Wedge Antenna, Wan-Yu Chen

Theses

The rigorous TE solution to the staircase model of the dielectric wedge antenna is presented. The fundamental, even TE surface wave mode of the dielectric slab waveguide is taken to excite a dielectric wedge which is formed by symmetrically tapering the slab. The method of solution is based on Marcuse's step-transition method. Radiation patterns of power gain are presented which show increased maximum power gains and narrower main lobe beamwidths for longer wedges. For higher dielectric constant material, the main lobe beamwidth is increased. In all cases examined, negligible sidelobes were obtained.

A Study Of The Properties Of The Biconical Antenna, Kurt Frank Hafner Jr.

Theses

Expressions are found for the fields produced by TM and TEM modes along a finitely conducting biconical antenna. Expressions are also found for the TM and TEM fileds along a biconical antenna having a lossy dielectric coating. It is shown that the antenna losses produce an anntenuation of the the fields along the antenna. It is found that because there is a dispersion of the fields along the biconical antenna, the attenuation produced by the losses is, in genaral, not characterized by simple exponential.

A solution is obtained for the fields of the TEM wave along a biconical antenna coated …