3-D Smith Chart software inventor Andrei Muller has been working overtime to demonstrate the unique capabilities of his brainchild to the engineering world, with the latest effort being a presentation at the Asia-Pacific Microwave Conference in December 2012 (see also IEEE June 2011 MWCL and the July 2012 Microwave Journal articles). Having begun as part of his doctoral thesis, the original 3-D Smith Chart program capabilities are being extended to make direct application to real-world RF design tasks more convenient. Examples are provided on Andrei's website that include amplifier stability circles, and complex matching of lossy lines. The primary advantage of the 3-D Smith Chart is its ability to display both the entire reflection coefficient and impedance planes, something even an extended 2-D Smith Chart cannot do. Access to the 3-D Smith Chart is free now, but a donation will be appreciated. I suspect it will not be long before you see the high-end simulators incorporating this tool.
I have a huge list of resources on the Smith Chart here.
Posted January 2013