Modelling a layout for UWB circuit design

[vaka85]

UWB circuit design

Hi all,
I need help for a small project that I'm doing. It's a microstrip circuit to connect an uwb antenna and a maxim chip (it's a switch), with a resistor and a capacitor.
Here is the schematic for the part of the circuit in question:

**broken link removed**

Since I have a very little knowledge in microwave office or any other design tool, could you help me? It would be helpful any tutorial or article or anything that can teach me how to do a design from the schematic...

Until now I've done this in microwave office, but I don't know how to go along with it...
**broken link removed**

I really need help because I have found almost nothing on the web..

Thank you very much (and sorry for my english)

 

[hanyahmedeg]

Re: UWB circuit design

hiii
Microwave office is simple and you can read the getting start of the Microwave office it's helpful and simple, has many examples and easy way to learn ......

 

[radiohead]

Re: UWB circuit design

First learn to understand what you are simulating. Then start using the simulator. Don't do it the other way around, that's useless.

 

[vaka85]

Re: UWB circuit design

I don't need to simulate...
I need to do the layout.
It seems that the only way it's the program help...

thanks

 

[Manjunatha_hv]

Re: UWB circuit design

Hello vaka85,

If you don't want to simulate & then only for Layout/Schematic design then
associte the footprints / artworks for the lumped elemnts & for the Chip components...

See the MWO getting started guide lumped Filter design example...

If you still have the problem then upload your MWO project file (*.emp) to guide you better...

---manju---

 

[vaka85]

Re: UWB circuit design

thank you, I'm trying with getting started guide. If I have some trouble I'll ask

 

[vaka85]

Re: UWB circuit design

Hi, I've read all the chapter about layout on getting started guide, but is absolutely useless.
There insn't a general example, but a specific one about a specific project.
So, I've to go on without the guide. Could you help me?

From the schematic in the first post, I've made this AWR schematic:
**broken link removed**

It's correct? (don't look at values, I haven't set them yet..)
Ah, another thing: is it correct to replace antenna and maxim chip with 50 ohm ports?

If everything is correct I can continue and study values and measurements...
Thank you very much

 

[Manjunatha_hv]

Re: UWB circuit design

Hello vaka85,

NO, it is not correct ...

The right way to model the layout is as shown below pictures...
When you use $ elements make sure you have connected nodes have W parameter otherwise use the regular microstrip elements such as MTEE with values instead of MTEE$...


---manju---

 

[vaka85]

UWB circuit design

thank you very very very much. You are very kind!

one last thing. Apart from measurement, infact I've to study that topic soon, can I put antenna and chip right where the track ends?

(sorry for my english)

and thanks again!

 

[Manjunatha_hv]

Re: UWB circuit design

Hello,

Yes, you can add Antenna em structure as a Subcircuit block & also the Maxim chip...
If you want to simulate then you need to have maxim chip model as S-parameters or Spice ckt...

See the attached picture...



---manju---

 

[vaka85]

Re: UWB circuit design

sorry but I haven't received the notification for the reply.
However... I think I've understood. Now I do some tries...

Thank you very much again


Valerio

 

[vaka85]

Re: UWB circuit design

new problem:

I've made some variations...

Since I have the evaluation board for the switch, I have to design only a small pcb in which there's a load for the rest of circuit.
This little pcb must have 2 sma connectors, one connected to ground and the other one connected to a resistor.

I've made this schematic:

**broken link removed**


but I suppose isn't correct because the 3d layout has some problems...
However, first of all: how can I assign a footprint to port1 and port2? Is it possible to assign to them a sma footprint?

very hard to find informations on this topic on the web...

thanks

 

[vaka85]

Re: UWB circuit design

some help please

 

[vaka85]

Re: UWB circuit design

up

 

[vaka85]

Re: UWB circuit design

Sorry, I haven't provided enough informations...

The goal of my little project is to design a load for an uwb switch.
I've made some changes since the first post.
Since the switch has to "switch" from an open position and a short-circuited position, I've to design this 2 loads, considering the (about) 5 GHz frequency and the 50 ohm impedance.

And since the switch has 2 sma connectors as outputs, they are the inputs of my circuit.
I've chosen to use coplanar wave guide instead of microstrip, and after calculating length and width of the line I've done this:

short circuited:
**broken link removed**

and open:
**broken link removed**

dimensions are not real and connector picture is only to understand where it is the sma connector...what do you think about them?

thanks