'atlc' is a CAD package used for analysing and desiging electrical transmission lines of arbitrary cross section. Also for the design of directonal couplers. Some parts are CPU intensive, so multiple CPUs are supported.
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.