Workshop Rectangular Patch Antenna

Introduction to ANSYS HFSS

Demo - Rectangular Patch Antenna Simulation

Principle :Design A micro-strip patch antenna for 5.2 GHz application and study s-parameter, Gain and field animations

Problem Statement : Micro-strip patch antenna of solution frequency F0 with FR4 Epoxy material as substrate.

Ansys HFSS is used for the simulation

Find the value of return loss for a given frequency range. Why it is minimum at the designed frequency?

Create the E-Field and J-Surface plots and Animate. Study the Fringing field effect of the antenna by using field

animations.

Plot the Radiation pattern in 2D and 3D format and find the peak gain, Directivity , efficiency, and Half power beam

width of the antenna.

Design a micro-strip patch antenna at 2.4 GHz with the same FR4 Epoxy substrate and calculate the parameters

mentioned above.

Analytical Approach- Design Equations

The Performance of the microstrip patch antenna depends on its resonant

frequency, dimension. Depending on the dimension, the operating frequency,

radiation efficiency, directivity, return loss are influenced. For an efficient

radiation, the practical width of the patch can be calculated by using the

following.

And the length (L) of the antenna becomes,

where

Where is the wave length, fr is the resonant frequency, L and W are the length and width of the patch element respectively and

r is the dielectric constant.

Analytical Approach- Design Equations

Characteristic impedance of the patch can be found by

Impedance of transition section:

Width of transition line WT:

Length of transition line:

Width of 50 microstrip transmission line:

Where Z0= 50

Length of the microstrip transmission line

Width of Edge Feed

Width of Feed Line

Length of Edge Feed

Length of Feed Line

Rectangular Patch Antenna Geometry

Creating the Design

Opening a New Project

In HFSS Desktop, click the On the Standard toolbar, or

select the menu item File > New.

From the Project menu, select Insert HFSS Design.

Set Solution Type

Select the menu item HFSS > Solution Type

Choose Driven Terminal

Choose Network Analysis

Click the OK button

Set Model Units

Select the menu item Modeler > Units

Select Units: mm

Click the OK button

Substrate Creation

Dielectric substrate material

Attribute Option

Creating the Patch Geometry

Creating the patch

Patch

Create Feed line & Edge feed

Edge Feed

Feed line

Creating the Ground Geometry

Uniting the Patch, Feed line and Edge feed

Note: The resulting united object name will depend on the order selected

(i.e. if patch is selected first, the final name will be patch)

Select Patch, Feed and Edge feed

Assigning Boundary Conditions: Perfect ESelect the objects named: patch (or feed), ground

Note: Your object names may differ depending on the order they

were selected in the previous unite operation. Select the object feed

or patch

Create Air Box

Assigning Boundary Condition -Radiation

ExcitationsPort Definitions

Wave Port

Represents 2D Cross Section of a transmission line

Can handle multiple modes or terminals

Defined on planar surface or face

Must encompass all fields that impact transmission line behavior

Computes these TL quantities

Characteristic Impedance

Propagation Constant

Field Configurations

Simulation Setup: Driven Modal, Driven Terminal

Lumped Port

Represents a voltage source placed between conductors

Can only handle a single TEM mode or terminal

Defined on planar surface or face

Must be placed between conductor

User must specify Characteristic Impedance

Simulation Setup: Driven Modal, Driven Terminal

Port SetupCreate Rectangle Used for Lumped Port

Set the Drawing Grid Plane

Select the menu item Modeler > Grid Plane > ZX

Dimensions of Lumped portPort Name: 1

Conductor: ground

Use as Reference:

Checked

Highlight Selected

conductors: Checked

Click the OK button

Analysis Setup

Adaptive Frequency

Basis Order

Iterative Solver

Note : -

The Solution Frequency sets:

The frequency used to create the adaptive mesh.

Defines the spatial resolution of the mesh through the

Lambda Refinement step

Lambda Refinement is wavelength dependant.

Determines the frequency used to evaluate the meshs

convergence.

Typically choose the highest frequency of interest or for

resonant antennas, the resonant frequency

Analysis Setup

Add Sweep

HFSS Frequency Sweep Type: Overview

Discrete Solves using adaptive mesh at every frequency

Matrix Data and Fields at every frequency in sweep

Fast - ALPS

Matrix Data and Fields at every frequency in sweep

Interpolating Adaptively determines discrete solve

points using the adaptive mesh

Matrix Data at every frequency in sweeps

Fields at last adaptive solution

Adding a Frequency Sweep

Analyze

Model Validation

Select the menu item HFSS > Validation Check

Click the Close button

Note: To view any errors or warning messages, use the Message Manager.

Analyze

Select the menu item HFSS > Analyze All

ValidateAnalyze All

Post Processing: 2D Rectangular Plot, S-Parameters

Minimum Return loss at 5.2GHz

Generate the Report

Post Processing Field Overlay, E-Field

Fringing field

Select the FaceRight Click

Generate the Report

Post Processing: 3D Radiation Pattern, Gain

Create a Radiation Setup

Post Processing: 2D Radiation Pattern, GainFor selecting E-Plane and H-Plane pattern

THANK YOU