yagiUda over a ground plane

How do I create a yagiUda antenna over a ground plane? How do you add height (above a ground plane) to the yagiUda?

How do you add a ground plane to a dipole (not a reflector as a reflector cannot be used as the Exciter for a yagiUda)?

Answer 1

[Vishwanath Iyer]

Hi Dean,

You can add the yagiUda as an exciter to a reflector. The same holds true for the dipole backed by a reflector. The following example illustrates this with a spiral: http://www.mathworks.com/help/antenna/examples/reflector-backed-equiangular-spiral.html?prodcode=AA&language=en

Some sample code for the yagiUda: r = reflector; y = yagiUda; r.GroundPlaneLength = 0.5; r.GroundPlaneWidth = 0.5; r.Spacing = 0.5; r.Exciter = y; %% See the geometry figure show(r) %% Calculate and visualize radiation pattern figure pattern(r,300e6)

Hope this helped.

[DeanW]

Thanks! Here's my working code:

% 20 meter, 14.000 to 14.350 MHz, 3-Element Yagi

clc; % Clear Command Window clear all; % Or just "clear" deletes all variables close all; % Close anything open format compact; % Suppress extra line feeds format short; % Integers, 4 decimal places

d = dipole; d.Tilt = 90; d.TiltAxis = [0,1,0]; d.Length = 10.171; d.Width = .0254; % 1 Inch Diameter

y = yagiUda; y.NumDirectors = 1; y.Exciter = d; y.DirectorLength = 9.569; y.DirectorSpacing = 4.026; y.ReflectorLength = 10.774; y.ReflectorSpacing = 4.026; y.Tilt = 90; y.TiltAxis = [1,0,0];

r = reflector; r.GroundPlaneLength = inf; r.GroundPlaneWidth = inf; r.Spacing = 10.576; r.Exciter = y;

fig = figure; fig.Name = '20 meter 3 element Yagi'; show(r); fig = figure; fig.Name = 'Directivity, dBi'; pattern(r,14.175e6,'Type','directivity'); fig = figure; fig.Name = 'Power, Watts'; pattern(r,14.175e6,'Type','power'); fig = figure; fig.Name = 'Pattern Aximuth'; patternAzimuth(r,14.175e6,[15 30 45]); fig = figure; fig.Name = 'Pattern Elevation'; patternElevation(r, 14.175e6, [270], 'Elevation', -180:5:180);