createFeed

Create feed location for custom antenna

Since R2023b

Syntax

createFeed(antenna)

createFeed(antenna,FeedLocation,NumEdges)

createFeed(___,Name=Value)

Description

createFeed(antenna) opens an interactive figure window, where you can select the edges for assigning the feed. To specify a region for the feed point, select two points, inside triangles on either side of the air gap or inside triangles that share a common edge. You can interactively add multiple single-edge and multi-edge feed points to the custom antenna or array.

createFeed(antenna,FeedLocation,NumEdges) creates the feed at the specified location and using specified number of edges.

createFeed(___,Name=Value) creates the feed with additional properties specified by the name-value argument.

Examples

Create Feed to Custom Antenna

This example shows how to create the feed point for a custom antenna in multiple ways.

Create Feed Edge on Shape

Create a rectangle with length 2 m and width 0.1 m. Assign it as a shape to a custom antenna.

r = shape.Rectangle(Length=2,Width=0.1);
c = customAntenna(Shape=r);

Create feed at [0 0 0] with number of edges as 1.

createFeed(c,[0 0 0],1);
show(c)

Create Feed Using 2-D Shapes

Create a waveguide shape.

wg_height = 0.0102;
wg_length = 0.024;
wg = shape.Box(Length=wg_length,Width=0.0229,Height=wg_height);
removeFaces(wg,3);

Create feed rectangle.

feedrect = shape.Rectangle(Length = 6e-3,Width = 6.0000e-05);
offset = -(0.5*wg_length)+6e-3;
[~] = translate(feedrect,[offset 0 -wg_height/2+(feedrect.Length/2)]);

Rotate feed rectangle by 90 degrees.

 [~] = rotate(feedrect,90,[offset 0 -wg_height/2+(feedrect.Length/2)],[offset 1 -wg_height/2+(feedrect.Length/2)]);

Create custom antenna.

ant = customAntenna(Shape=wg);

Pass feed location, number of feed edges, and feed shape to create the feed.

createFeed(ant,[offset 0 -wg_height/2],1,FeedShape=feedrect);
show(ant)
view([-24.0 -48.9])

Create Multi-Edge Feed

Create a waveguide shape.

wg_height = 0.0102;
wg_length = 0.024;
wg = shape.Box(Length=wg_length,Width=0.0229,Height=wg_height,Center=[0,0,0.5*wg_height]);
removeFaces(wg,3);

Create custom antenna.

s = shape.Circle;
s.NumPoints = 6;
s.Radius = 0.001;
wg = extrude(wg,s,Height=0.005);
ant = customAntenna(shape=wg);

Pass feed location and number of feed edges to create the feed.

createFeed(ant,[0 0 0],6);
show(ant)
view([-19.3 -18.8])

Input Arguments

antenna — Custom antenna

customAntenna object (default)

Custom antenna to create the feed, specified as a customAntenna object.

Example: customAntenna(Shape=shape.Custom3D)

FeedLocation — Location of feed

[0 0 0] (default) | N-by-3 real matrix

Locations of the feed points, specified as a N-by-3 matrix of Cartesian coordinates in meters. N represents the number of feed points. See Feed Model for more details on the feed.

Example: [0 0 1]

Example: [0.01 -0.0065 2e-3;0.045 -0.0065 2e-3]

Data Types: double

NumEdges — Number of edges for feed

1 (default) | 1-by-N vector of positive integers

Number of edges for the feed, specified as a 1-by-N vector of positive integers. N represents the number of feed points.

Example: 2

Example: [1 1]

Data Types: double

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: FeedShape=shape.Rectangle

FeedShape — Shape of feed

shape object

Shape of feed, specified as a shape object.

Example: shape.Rectangle

Version History

Introduced in R2023b

R2024b: Interactively select multiple feed points

The createFeed function now enables you to interactively add multiple single-edge and multi-edge feed points to the custom antenna or array.

Provide customAntenna object as the only input argument to the createFeed function to open an interactive window. Click the feed edges to select them. After selecting the edges, click OK in the interactive window to create feed points.