Hi,
To get the desired results you would be like to do parametric sweeping and optimization.
1) Parametric: Define one or more variable sweep definitions, each specifying a series of variable values within a range, and HFSS solves the design at each variation.
2) Optimization: Identify the cost function and the optimization goal. Optimetrics changes the design parameter values to meet that goal.
Most probably doing parametric sweeping will give you the satisfied results. I am briefing procedure to do the same. Let me assume you are interested in varying the resonating length of patch antenna to get the target frequency.
First step is create a variable, go to Project-à Project Variables, window will popup like this.
Add the variable (say Patch_Length), this will be sweeped later in parametric analysis.
Right click optimetric-->Add--> Parametric Setup Sweep Analysis will open
In sweep Definitions Tab, Click ADD button.
Select the variable you want optimize for eg. $Patch_Length, Mention the variation you want in start, stop, step. Press ok.
Then goto optimetrics --> Analyze all parametric.
During the parametric analysis, Optimetrics will solve the design at each variation.
You will compare the results to determine how each design variation affects the S-parameters and return loss the patch. These results will help to determine a
reasonable parameter variation to achieve desired resonant frequency.
Hope this helps...