Yagi antenna analysis with the Yagi-Uda Project.

# Yagi antenna analysis with the Yagi-Uda Project

Written by Dr. David Kirkby, G8WRB. email david.kirkby@onetel.net
Homepage: http://www.medphys.ucl.ac.uk/~drkirkby/

Introduction

The Yagi-Uda project is a set of programmes for designing, analysing and optimising Yagi-Uda antennas, with 2 or more elements, such as shown below.

The programmes were developed by Dr. David Kirkby (G8WRB) and run on unix systems. They have been successfully compiled on Solaris 8 (SPARC), Red Hat linux (release 6.1 on a PC) and FreeBSD on a PC. In each case the gcc C compiler (2.95.1 or 2.95.1) were used. There are some old 32-bit DOS executables, but they are no longer updated. There are no executables for any version of Microsoft Windows (Win 3.1, 95, 88, NT or 2000).

Several programmes are included:

- first
- input
- yagi
- output
- optimise
- dipole

A few other programmes that were developed for test purposes are included, but there are not needed for normal use.

Download the latest (version 1.19) source file for unix

Here are the old source files - versions 1.15 1.16 1.17-

Building the programmes

Designing an antenna.

Several stages are needed to design a Yagi-Uda antenna using these tools

1) What you do first depends on whether you have an antenna design you wish to analyse (like one from a book) or if you want to design one using the tools in the Yagi-Uda project.

a) If you have an antenna you wish to analyse, use input to specify it in the form suitable for the programmes in the Yagi-Uda project.

OR

b) Assuming you don't know exactly what you wish to analyse, you can let the programme first design you an antenna. It wont be good, but it is sufficiently close to optimal that it can be optimised with optimise.

2) Calculate the currents in the antenna, using the programme yagi

3) Calculate the performance of the antenna using the programme output.

4) Look at the files created by output to see how good the antenna is. A file filename.gc can be read into gnuplot.

5) You may only want to do 1-4 above, but you will probably want to optimise the antenna, using optimise

For more informaiton
The programmes have on-line man pages, but there are available in html format too. There were converted to html format using the programme man2html

- first.1
- input.1
- yagi.1
- output.1
- optimise.1
- dipole.1

There are also some files describing the file formats.

- first.5
- input.5
- yagi.5
- output.5
- optimise.5

Dr. David Kirkby, G8WRB. email david.kirkby@onetel.net
homepage: http://www.medphys.ucl.ac.uk/~drkirkby/