The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	Microstrip zero-sum antenna; CAD and experimental study
Author:	Lam, Tuan H.
View Online:	njit-etd1997-031 (x,80 pages ~ 5.7 MB pdf)
Department:	Department of Electrical and Computer Engineering
Degree:	Master of Science
Program:	Electrical Engineering
Document Type:	Thesis
Advisory Committee:	Niver, Edip (Committee chair) Rosenstark, Sol (Committee member) Manikopoulos, Constantine N. (Committee member)
Date:	1997-10
Keywords:	Antennas (Electronics). Microwave transmission lines --Mathematical models.
Availability:	Unrestricted
Abstract:	A microstrip antenna array consisting of two elements combined with a stripline hybrid (rat-race) ring coupler is used to implement a zero-sum antenna. Numerical optimization of individual antenna elements in terms of feed location and patch size was achieved using IE3D (Zeland Software Inc., Fremont, CA), a fullwave 3-D planar electromagnetic simulation software. Further, design of a hybrid (rat-race) ring coupler in a stripline environment was carried out, yielding the sum and difference functions as 0.5 dB and 40 dB, respectively. A combination of a two-element antenna array and a hybrid (rat-race) ring coupler as a zero sum antenna has been studied numerically revealing that 40 dB differences can be expected between the sum and difference patterns in the forward direction at the operating frequency. Experimental results using MC5 material (εr=3.26 and thickness t=60 mils) (Glasteel Industrial Laminates, Colliervile, TN) have shown that satisfactory performance can be achieved at the chosen operating frequency f=2.254 GHz.