Nope or else I would know how to do it
With your lack of RF design knowledge, all I can suggest is go with the 2.54mm wide trace and keep it as short as possible.
Since the antenna is 50-ohms (or so it claims), a 112mil trace from the SMA to the Bluetooth device should do the trick (you may need to taper the trace at the SMA interface). Make sure that you have good vias connecting top ground to bottom ground. Do not run long traces/wires to connect ground points. You want ground planes, and vias connecting the ground plane to the required tie-points (as close as possible).
This is, of course, assuming the Bluetooth device is already matched to 50-ohms. If it isn’t, you must then make a matching circuit (the device datasheet should provide you good guidance on this). This could be as easy as a 50-ohm pad (i.e. lossy match / attenuator - sacrifice loss for efficiency), or a reactive matching network (either LCs or microstrip matching - little loss, more complexity).
I didn’t get it if I have a top ground plane and a bottom ground plane they shouldn’t be connected automatically? Or should I connect them using vias? How to do that?
They might be connected by, for instance, component grounds, or they might not. Adding several vias is important, additionally, otherwise they won’t be at the same potential to RF at every point. Adding vias will be in the Eagle documentation.
So I place vias anywhere on the top and the bottom of the board and name them all to GND?
You should distribute them evenly over the area, of course.
ElieGW:
I didn’t get it if I have a top ground plane and a bottom ground plane they shouldn’t be connected automatically? Or should I connect them using vias? How to do that?
If you need help with laying copper pours, watch my video on doing that in Eagle. The video is part of a tutorial series I did on Eagle, starting with the very basics and going right through the creation of an actual board.
Is this example good?
You don’t have any vias.
Well I draw the microstrip line connecting the middle pad of the SMA edge to the RF pin of the bluetooth module then I added a ground plane on both top and bottom layer and used the auto route button so apparently one via was added automatically and I don’t have any idea how I can connect the top layer to the bottom layer if I add other vias.
It’ll be in the documentation somewhere.
In fact, there is nothing about that in the documentation
It’s called a free pad, with the software I use.
I dunno if you ever checked the Eagle help but there is nothing in there you can’t make a search even
I meant the documentation, not the on-line help. I’ve always tried to avoid using Eagle.
I don’t have any. Anyway I added some vias named them to GND. If I click on view/info then choose a via I recieve this:
Can anyone see something suspicious in this schematic?
Don’t know if the schematic question is a trick one or not. But I guess it looks ok.
Look at the layout of [this module. I would think you can have more vias in there, but if nothing else; it’s a working module.](http://www.sparkfun.com/commerce/product_info.php?products_id=158)
Well no the schematic question is not a trick that’s the circuit I am trying to do I just wanted to verify if I missed something. My problem is the vias where, how and why place them? Also how to connect top ground plane to bottom ground plane using vias (just place vias anywhere on the board and name them GND where my bottom an top ground planes are also named GND?)