Tutorial: Bent Patch Antenna


 * Download the latest matlab file using gitweb: Bent_Patch_Antenna.m



Requirements

 * openEMS v0.0.31 or later

This tutorial covers

 * setup of a Bent Patch Antenna (see for comparison: Tutorial: Simple Patch Antenna)
 * setup of a cylindrical FDTD mesh
 * calculate the S-Parameter and input impedance
 * calculate far-field pattern 2D/3D

Matlab Simulation Script

 * Start the script within an empty environment:


 * Specify drawing units


 * Specify the patch size, substrate properties, and feed point


 * Set up the simulation

Note that the coordinate system is set to cylindrical.


 * '''Calculate angular sizes

Calculate angular sizes (in radians) for the patch width, substrate width, and position of the feed point.


 * Now create the objects

Note that although the patch and substrates are curved objects, the function  is used. In a cylindrical coordinate system the start/stop coordinates are in the form .


 * Add a dump box for the surface current on the patch


 * A ground plane is placed on the backside of the substrate

Note that this metal structure has zero thickness.


 * Add an excitation port


 * Define the mesh

The simulation space is a C-shaped extrusion which extends from -135° to +135° in azimuth.




 * Create a NF2FF box

Again, even though this is called a box, because the coordinate system is set to cylindrical, the arguments will be assumed as.


 * Save and run the simulation

Post Processing

 * Plot the feed-point impedance and reflection coefficient

This is done by finding the frequency index for the minimum value of s11, and then using the index to determine the frequency.
 * Determine the resonant frequency and save the current distribution for plotting


 * Calculate and plot the far-field patterns etc.

Results