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3D Smith Chart


The 3D Smith chart tool was firstly introduced by Andrei Müller and co-authors in 2011 in “ A 3D Smith chart based on the Riemann Sphere for active and passive microwave circuits- in IEEE Microwave and Wireless Components Letters”. Since that moment Andrei and the co-authors extended the work in the telecommunications journals publications “ The 3D Smith chart and It’s Practical Applications”- Microwave Journal 2012, “Apollonius unilateral transducer constant power gain circles on 3D Smith charts”- IET Electronics Letters -2014 and “New properties of purely reactive Foster and non-Foster passive networks”-IET Electronics Letters, October 2015. In the October 2015 article a new application of the 3D Smith chart is highlighted, mainly it’s new capability (undisclosed completely yet) to deal with negative group delays. The new capabilities of the tool are going to be presented by Andrei at Asia Pacific Microwave Conference in Nanjing in December 2015.


The tool is a correct generalization of the classical “Smith chart-2D” which is mainly used for passive circuits. The 3D Smith chart tool can deal with active and passive circuits simultaneously, with amplifier stability circles, complex ports matching and newly with other phenomena too. The tool aims to complement the classical 2D Smith chart tools used in Telecommunications courses worldwide and to become a handy fast tool to help in the visual design of microwave circuits, such as : amplifiers, antenna, matching networks or filters.

To initial efforts started in 2011, the Computer engineers Alin Moldoveanu, Victor Asavei, Cristi Fleischer,( Bucharest), Prof . Stepan Lucyszyn (London) and Dr. mat Esther Sanabria-Codesal ( Valencia) contributed in the recent years in the extension of the chart capabilities too.


Andrei Müller was born in Bucharest and is currently mainly working on a project with the European Union at the Valencian Telecom Innovation Center, “Efficient Synthesis and Design of Reconfigurable MEMS-based Band-Pass Filters in SIW Technology” (02/2013-02/2017) on the synthesis of cross coupled filters for satellite applications.
Andrei did a PhD in Telecommunications, in which he completed several stages in Munich ( 18 months), South Africa ( 3 months) and Pure and Applied Mathematics Institute Valencia (7 months). He completed a 1 year Post Doc in Brest/ Brittany France (2012) in the design of SIW filters in a research project with the French army.