MMSIM 12.1 SpectreRF -- Preview of Coming nport Attractions! Part 2

19 Nov 2012 • 2 minute read

Greetings,

MMSIM 12.1 contains many new features to aid RF designers. Many of these changes are described in my Part 1 blog post.
I've saved my favorite for last....here's a preview of the changes to the nport component in MMSIM12.1.
1. The Edit Object Properties/Add Instance form has been revised for better usability.
2. For most S-parameter files, only the S-Parameter file name and the number of ports need to be specified. (See the red boxes in the GUI below). The default settings for all of the other properties are suggested.

3. When you select the Browse and select s-data file button, the following GUI appears and allows you to browse and select the desired s-parameter data file. Once you do that, the filename is populated into the GUI..
4. The causality check is more robust.
5. The impulse response is adaptively sampled and is automatically cached so that it can be re-used in subsequent simulations. The cache location can be specified so that multiple users can share the same caching directory. The two options that control caching are located in the ADE options; Simulation -- Options -- Analog.
nportirreuse enables caching of the impulse response. Keep this at the default to save time.
nportirfiledir controls the location of the cached impulse response files. The default (blank) sets the location to /home/<username>/.cadence/dfII/mmsim. When a directory name is specified in the nportirfiledir option, the impulse response files are cached in the specified directory. This can be a shared directory between users, as long as all the users have write permissions in that directory.
6. Improved error messages makes troubleshooting problematic s-parameter files much easier!
The S-Parameter file is examined for common problems like discontinuities in the data, or imaginary part at DC, and this information is sent to the Spectre output file.
Passivity and Causality violations reported in the spectre output logfile have more useful information.
7. New Touchstone formats supported:
Touchstone 1 file format with multiple impedances.
Touchstone 2 file format.
I'm sure you'll agree that the new nport is much easier to use in MMSIM12.1.
Have fun simulating!
Best Regards,
Tawna

P.S. Make sure you are using IC6.1.5 ISR14 or later to see these new features in the environment.