AnsweredAssumed Answered

Design a Spiral Antenna using Momentum

Question asked by keldoud on Jul 19, 2006
Latest reply on Jul 25, 2006 by ELTZ

Like • Show 0 Likes0
Comment • 3

ADS 2004A. OS: Windows

Hi,

I am new to using ADS, and I am trying to design & simulate a microstrip circular Archimedian spiral antenna using Momentum.

I had the problem of how to draw a spiral on Schematic. I found in the Component Palette List, under â€œTLines-Microstripâ€

No one else has this question

Outcomes

3 Replies

keefe Jul 21, 2006 1:39 AM
Mark Correct
Correct Answer
If the component looks like what you want, then you can absolutely use it! Since you want to run Momentum on this antenna, you could even just place this component from the same palette library in a layout window if you want. If you place it in a schematic first, make sure that you also place a MSUB substrate definition component. Then use the "Layout-->Generate/update Layout" menu in the schematic window. Then you can use the "Momentum-->Substrate-->Update From Schematic" menu in layout to bring over the substrate stack-up information.

The rest of your effort will be in setting up the Momentum simulation (proper ports, meshing, and frequency sweep).

Enjoy!
Like • Show 0 Likes0
Actions
keldoud Jul 21, 2006 5:45 AM
Mark Correct
Correct Answer
Thanks Keefe, that was really helpful. Cheers!

keldoud
Like • Show 0 Likes0
Actions
ELTZ Jul 25, 2006 1:42 AM
Mark Correct
Correct Answer
MSIND sure can be used to generate a spiral layout from schematic. I did that for simulation of stripline spiral inductors, for which there is no such thing as an analytical model.

The Microstrip substrate definition in the schematic of the spiral design is only a dummy in this case, it's only needed to prevent an error message during automatic generation of the layout. All substrate specification has then to be entered via the Momentum Substrate Editor manually.

By creating a so called layout component from this first generated layout and assigning the N (number of turns) of the MSIND instance as a design parameter of this layout component I was able to generate the layout and simulate the spiral's S-parameters for various N from the top level schematic.

But be aware that antenna parameters, surface currents and the like are only available for the last EM-simulated configuration.

Usually you want to have the inner part of the spiral at a certain position in the layout, particularly when using two spiral arms and a balanced feed. For some odd reason the AEL macro generating the layout starts at the outer arm. So even if you mark the spiral's position as fixed for the automatic layout generation process, it is the outer pin which stays fixed and depending on the number of turns your inner part goes anywhere.

Easiest workaround is to attach some (dummy) component (port, MLIN, MBEND or so...) to the inner pin and fix the position and orientation of this one, leaving the spiral's position free. Then make sure that you select the fixed helper component as starting component for the layout generation.
Like • Show 0 Likes0
Actions

Design a Spiral Antenna using Momentum

Outcomes

Related Content

Recommended Content