The steps which is used for designing any microwave Microstrip circuits is the same which in general includes:-

Put the design specifications required for your target (in your case antenna gain over the band-radiation pattern, input impedance,.....)

Use the available software (CST, HFSS, COMSOL,.....) tool for the design that covers the specifications required.

Carry out the sensitivity analysis to see the critical parameters for the design.

Go to the fabrication process, may be some dimensions may not realized.

Return again for the simulation to cover the fabrication requirements.

Measure the antenna performance. 

Fill the gaps between the measurements and the simulation.

I enclose for you a very useful paper that covers the antenna design tools and measurements.

Good Luck.

Prof. S. EL-Rabaie

Dear Mr. Patel,

Fabrication of Microstrip Antenna depends on the machine you are using for fabrication. In case of an LPKF machine, it is recommended to draw the design according to scale in Corel Draw then take inverted black and white image. White being the region of copper and black the region that is etched. Keep the resolution higher than 600dpi and print it on the image negatives. After that, place the substrate between the top and bottom separately printed plastic sheet negatives. Use "+" sign markers equi-distant from the four ends of the printed copper part on the top and bottom surface in order to allign top and bottom surfaces properly. I have attached a Corel draw file for your assistance. LPKF machine provides accuracy upto 0.5mm.

The other method is simple one but the accuracy may be compromised. You will need a gerber file. If you are using HFSS software, export using HFSS -> SAT export -> AutoCad import of SAT -> DXF export -> ADS/Momentum DXF import -> Gerber export.

After this, import the gerber file in Autocad. Then print it on sticker sheet or Epson's picture paper using a laser printer. Then its the simple PCB etching procedure using ferric chloride.

http://hackaday.com/2008/07/28/how-to-etch-a-single-sided-pcb/

Hope this helps.

Practically, there are things to consider before going on to fabrication. Do you have a reliable PCB lab facility?

Because, small size antennas are hard to realize while minimizing errors using unreliable facility. How many layers does your antenna have? Alignment of printed designs on the copper layers during lamination stage is very sensitive part (such as misplacing the ground plane), where you must do it with careful attention. Finally, removing all unwanted copper after etching stage is also an important practice. Many of unexpected results form measurement are caused by copper remains from etching stage.

Hope this gives you a clear idea

Thanks  El-Sayed Mahmoud El-Rabaie,

Zeeshan Ahmed ,

Waddah Al ashwal .

Well ,Specifically  I would like to know if  it is possible to model the imperfections of the PCB fabrications  in the Software itself. Like we model in case of CMOS VLSI design for IC do we have  any  process aware simulation softwares for the design of   MSA design also.

For printed antennas designed using HFSS following are the steps for antenna fabrication:-

* Click Modeler in the Menu bar of HFSS and then click Export.

*  Select the file type to be .dxf and provide name to the file and location.

* Keep in mind that HFSS will export 2D design of the antenna which means whatever is at z = 0 mm. If you want to the top patch design also then you have to shift that to z = 0 mm and export it as  a separate file.

* Then the dxf file can be opened using some CAD software or Corel Draw.

* Fill the region where you want conductor and rest to be white. So that it can be etched.

* Follow the conventional PCB fabrication process i.e. screen printing, masking, etching etc.

The whole process is also explained in the Tutorial video:

https://www.youtube.com/watch?v=ros0ugjv1qQ