الفهرس 
Computer aided design of microstrip circuits I Review.Only 14 pages are availabe for public view
 |  | from | 232 |  |  |
| | | from | 232 | | |
Abstract
Realization of masks is the most im ortant
step in
production of microstrip circuits. It is also the most critical
and time - consuming one . Up to now there are two ways to make
the mask
1) from a large-scale drawing, the mask is cut by hand or by
hand - driven coordinograph on a cut ”n” strip fi m
2) With the help of a powerful computer running analysis and
synthesis program and driving the coordinograph via a graphic
program. This approach is the most complete one but is very
expensive , in both software and hardware
In this thesis we produced a program written in BASIC and
running on a micro-computer connected to a plotter
The program
is interactive and self documented and all necessary informations
and instructions appear on a screen . The desgin data such as
permittivity and thickness of the substrate, input impedance
frequency, ...etc. are entered
The program computes all
necessary parameters using formulas which yield an excellent
approximation
taking into
account
metal
thickness and
dispersion. After indicating the final dimensions, the plotter
draws automatically the mask on a paper - sheet.
A circuit of the balanced mixer is chosen as an application
example that contains many components all connected together. The
mixer is realized and measured to illustrate the applicability of
the design procedure and compatibility with the theoretical
behaviour ,
The material of the thesis is divided into seven chapters and
fi ve appendi ces
Chapter (1) presents an introduction about the computer aided
design approach with its three important segments namely modeling,
analysis and optimization .It also introduces a brief summary
about the available programs, microstrip technology
and the
scope of this thesis .
Chapter (2) describes the design and synthesis of a single
microstrip line, the design of symmetric coupled lines and hybrid
junctions namely the branch line coupler and the rat race
junction. Design examples for these types of elements are given
by the aid of subroutine programs .
Chapter (3) presents different types of microstrip filters
namely low pass using single and coupled microstrip lines high
pass filter and parallel coupled band pass filter
Design
examples for each type of filter are also presented and drawn
using the subroutine program and the plotter
Chapter (4) describes representation of discontinuities such
as : open end, short circuit ends, right angled bends, steps in
widths, T- junctions ,...etc. Some matching sections are also
presented namely tapered lines
edge coupled impedance
transformers , open ended coupled microstrip stubs
shorted
coupled microstrip stubs and microstrip radial stub.
Chapter (5) introduces the design of a single balanced mixer
.....
circuit . This circuit is chosen as an example that contains many
elements such as branch-line coupler
matching sections
transformers and low pass filter. The mask of the mixer is drawn.