spiral antenna

Hi all,

I'm designing the spiral antenna (microstrip type). I don't know how to have the negatives of PCB drawing (for etching process). Can we use Protel or some PCB design tool like that to draw the spiral model. A suggestion is to use autoCAD because we can draw the spiral by programming the spiral function.
(I use CST to design the antenna.)
Does anybody have experiences about this problem? Please give me some suggestions.
Thanks for u help!

To design a spiral antenna using microstrip, I prefer using CST Microstripes. This simulator has a feature that is "law". This tool is used to specify the parametric definition of a curve using mathematical functions, so that we can draw a spiral easily. You no need to export or import the spiral, you can simulate it directly.

If you face the problem in drawing the spiral, you can use antenna magus. It has template of spiral antenna. But if you use antenna magus to design the spiral antenna, you need the latest software of feko or CST to open it.

Hi there,

I've drawn the spiral model in CST MWS and simulated this type of antenna in CST. Now I want to manufacture this antenna but I don't know how to have the negative draw of the spiral to do the etching process. I wonder that if it is possible to draw the spiral using some well-known PCB design tools such as Protel, OrCAD or not.
A suggestion is using AutoCAD to draw the spiral, then convert the file .DXF to GERBER file type which is accessed by photoplotter machine. The photoplotter then makes the negative draw (for etching). I'm so confused because I.m not familiar with AutoCAD (perhaps I have to write a macro in autoCAD to draw the spiral).
Any suggestion is appreciated.

Thanks so much.

hi , i suggest to use momentum in Agilent ADS , you can draw your spiral antenna and simulate the S parameters and the radiation pattern of the spiral antenna easily.

In my country, I can make a negative film for etching with a corel draw format. I don't know the process but that is what I do to make a negative film. I'm not doing that by myself, but I send the corel draw format file to the place (third party) that can make a negative film and then etching the antenna.

Hi thephuong07

the simple way to do it is to export the spiral to gerber, from cst. go to file -> export to gerber then send the file to the photoplotter manufacturer and he will do it for you. this is the standard and common way to do it.
normally the photoplotter designed to have the negative draw for manufacturing. it is the manufacturer job you just give him the positive spiral drawing saying what you need and he will do it for you.
usually they need gerber file. dxf can be good too. but I think that the input file to the
photoplotter is gerber file.

I hope you have the license for gerber export in cst. if not export from cst to dxf it is
default export from cst.

pl