Steps involved in building(analog) a microstrip patch ant.

steps involved in antenna design

Hey, guys. I'm an electrical engineering student and I'm designing a microstrip patch antenna for my antenna class. I've already completed the actual design and simulation of the antenna. Now, I have to building the antenna (mill it). Do anybody know the steps involved in doing this--especially if you're using HFSS to design it?

Any help would be very much appreciated. Thanks!

dxf hfss import height

if you are using hfss the easy way is to build a negative and then you can either etch it in you home like a regular pcb or get some professional service to make it.


BUILD A NEGATIVE: you can download macromedia freehand demo and in freehand draw 2 rectangles one being the patch itself and the other the feed line, put the feed line next to the feed point and as yhou complete the geometry you have to save it as pdf so you can print it and not to worry about scale.

whether you build it yourself or not you have to be absolutely sure your manufactured the antenna in the correct substrate you simulated it.
mainly substrate height and relative permitivity (relative epsilon) are the main substrate parameters you have to take into account.

isopro software

pabloec said:

if you are using hfss the easy way is to build a negative and then you can either etch it in you home like a regular pcb or get some professional service to make it.


BUILD A NEGATIVE: you can download macromedia freehand demo and in freehand draw 2 rectangles one being the patch itself and the other the feed line, put the feed line next to the feed point and as yhou complete the geometry you have to save it as pdf so you can print it and not to worry about scale.

whether you build it yourself or not you have to be absolutely sure your manufactured the antenna in the correct substrate you simulated it.
mainly substrate height and relative permitivity (relative epsilon) are the main substrate parameters you have to take into account.

Click to expand...

We actually have a milling machine at school. It's connected to a computer with HFSS on it. I just have no idea where to start to get my antenna produced.

build a analog antenna

i think that in designer you can export to gerber files but i have not used that feature.

what is microstrip ant

I recently had to figure this out myself. There are several ways to get to the end result, but they're all heavily dependent on your antenna and milling machine.

I used a T-Tech milling machine with an outdated version of Isopro software. I’ll tell you how I would accomplish your problem using this software, and hope that it generalizes to your case.

If your antenna is a basic rectangle without any cut-outs or curves, then you can export a DXF of your patch layer from HFSS. Bear in mind that a DXF only takes a cross-section of the xy-plane at z=0. Open your milling software, and import the DXF, making certain that all of the units and trailing/leading zeroes match the HFSS output. Orient the imported patch to efficiently fit on your board. Words in quotes correspond to buttons in Isopro. Create an “isolation” layer using the tool size of the bit you plan to put in the machine. It’s important to use the right size because your antenna dimensions will be off by a few mils if you don’t. Create a “rubout” layer to show the milling machine what’s supposed to be cut away. “Initialize” the milling machine. Put your material on the mill, and make sure it’s secured with either pins or a lot of tape. “Run” the rubout layer, inserting the bit you specified earlier. If you need to drill holes for a through-hole coax feed, then you can switch bits and tell the machine to do it. Or you can just remove it and use a drill press.

For some reason, most CAD software can’t properly read curves from DXF files created with HFSS, so you’ll have to use another method. I assume that you probably have access to Ansoft Designer since you’re at a university (by the way, which one, if you don’t mind my asking?). Designer has no issues with curves from HFSS, so open Designer and create a new Planar EM design. I think you can directly import an HFSS geometry, but I generally just import a DXF. Next export a gerber of the layer with your patch, and import it into your milling software. Proceed as described above.

Without a detailed manual or an experienced user to guide you in person, the intricacies of milling are tricky at best. I recommend that you befriend a graduate student or a worker in your department’s machine shop who knows how to use the milling machine. Most of the graduate students will empathize with your situation if they’re not total jerks (or if they don’t have papers due the day you ask them).

Good luck.

Oh yeah, I don't quite understand what you were getting at with the "analog" in your title. Care to share?

Re: Steps involved in building(analog) a microstrip patch an

analog: instead of building it in software alone i'm actually building a tangible antenna.