Modulated Sinc Source Waveform

sin(w×t) (w×t)

In the time-domain, sinc(w×t) looks like this, a sine wave gradually increasing to its maximum amplitude, then decreasing to zero. This is a sinc waveform with a the Sinc Frequency parameter set to 1 GHz, and Sinc Modulation set to zero.

This is the same sinc waveform, but now with Sinc Modulation set to 10 GHz, modulating the sinc by a 10 GHz sine wave.

The extent of the leading and trailing tails is controlled by the sigma parameters, like the Gaussian pulse waveforms. Rise Sigma controls the length of the increasing half, while Fall Sigma controls the length of the decreasing half.

The modulated sinc waveform has a well-defined bandwidth, as show by this frequency-domain plot of the same waveform show above. This is the attractive attribute of the modulated sinc.

The smoothness of the frequency-domain curve is controlled by the sigma parameters, a large value giving a smoother curve but taking a longer simulation time.

This output option is for users who wish to create their own post-processing routines for the far field data. Currently, LC has no capability for reading or processing the saved grid face data.

Added output buffering for point probes, removing any open file limit.

In the past, LC kept a file open for each point probe being saved during a simulation. If a large number of probes were being saved, the number of required open files often exceeded the default maximum enforced by the operating system. The new buffering scheme removes this restriction entirely, as at most one point probe output file is open at a time.

Updated online help.

The online help within LC has been updated to the latest revision of the user's guide, version 2.7.

Fixed value count in point output files for interrupted simulations.

Fixed a small memory leak in free_model_file.

Fixed some PML problems related to multiple dielectric materials.

In simulations using the PML absorbing boundary condition, the extension of dielectric regions touching the outer faces of the simulation grid was causing a number of problems, including artificial reflections and numeric instability in some models. This fix corrects this condition,

Fixed the "invalid parameter attributes" visual-matching errors.

Fixed wizard source/submesh overlap bug.

Fixed plane probe in a variable mesh bugs.

Fixed mesh of rotated block causes hang.