Ansoft High Frequency Structure Simulator (HFSS) is an interactive software package for calculating the electromagnetic behavior of a structure. The software also includes post-processing commands for analyzing the electromagnetic behavior of a structure in more detail. Using Ansoft HFSS, you can compute:

· Basic electromagnetic field quantities and, for open boundary problems, radiated near and far fields.

· Characteristic port impedances and propagation constants.

· Generalized S-parameters and S-parameters renormalized to specific port impedances.

· The eigenmodes, or resonances, of a structure.

Ansoft HFSS, a commercial full wave finite element simulation package. This package uses an iterative adaptive meshing technique1 which divides the structure into a number of tetrahedra and then solves for the fields in these tetrahedra. The number of tetrahedra is then increased and the process is repeated in an iterative fashion until a desired convergence is achieved.

We can analyze antennas, microwave transitions, launchers, waveguide components, RF filters, and three-dimensional discontinuities, just drawing the structure, specifying material characteristics, and identifying ports and special surface characteristics in HFSS. HFSS automatically generates field solutions, port characteristics, and s-parameters.

The finite element method (FEM) is used for finding approximate solutions of partial differential equations (PDE) as well as of integral equations. The solution approach is based either on eliminating the differential equation completely, or rendering the PDE into an equivalent ordinary differential equation, which is then solved using standard techniques such as finite differences, etc.

The ansoft hfss window has several optinional panels:

1. A Project Manager which contains a design tree which lists the structure of the project.

2. A Message Manager that allows us to view any errors or warnings that occur before we begin the simulation.

3. A Property Window that displays and allows us to change model parameters or attributes.

4. A Progress window that displays solution progress.

5. A 3D Modeler Window which contains the model and model tree for the active design.

The Ansoft HFSS provides an intutive, easy to use interface for developing various models. Creating designs, involve the following:

1. Parametric Model Generation – creating the geometry, boundaries and excitations.

2. Analysis Setup – defining solution setup and frequency sweeps.

3. Results – creating 2D reports and field plots.

4. Solve Loop – the solution process is fully automated.