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Currently I supervise a PhD student, Alireza Motevasselian as well as two exchange PhD students. We are working on different aspects around electromagnetic calculations and understanding of finite array antennas in different geometrical settings.
Since May 2009 we are participating in the CHASE network it is a VINN Excellence center around antenna systems. We are one of several groups working in the antenna system simulator project. One of our tasks is to integrate array antennas and their optimization, into the simulator. This includes both understanding of group antenna effects as well as numerical algorithms.
Recently we started to study how scattering limitations could be related to antenna applications in the telecommunication sphere. We got our proposal "Access technologies: multiple access, multiple users, multiple distributed antenna system" accepted. It is a joint work with of different groups at KTH and LTH together with three Chinese universities. This project will run over three years starting the summer of 2008.
I am interested in wide-band antennas and reduction of radar cross section against PEC structures. I have joined a NFFP project, which is a research network/program within Sweden for research with applications within the aeronautical area. This is a joint project between our group at KTH (with Patrik Persson and Alireza Motevasselian) and the Electromagnetic Theory Group at LTH, together with industrial representatives from Saab AB and Volvo Aero Corporation. This project had its kick-off May 2007 and has continued until 2009. Reduction of radar cross section has been studied. Additional research is conducted by Martin Norgren and the Ph.D. student Anders Ellgardt on antennas and forward and inverse scattering. Here we are studying stealth properties of wings with integrated antennas.
The past few years I have been working with nonlinear phenomena. I have studied dynamics of solitons and solitary waves. These waves occur as a very robust effect due to the nonlinearity of the medium. The waves have interesting properties, like almost survival under perturbation. They appear (among other) in the area of physics, electrical engineering and mathematics and there they describe for example Bose gases, boson and fermion stars certain water waves, optical solitons, certain plasma waves (Langmuir waves). For a more extensive description of solitons see e.g. wikipedia.
One of my research subjects has been to find out what happens to a free soliton when it is perturbed by an external potential, this potential represent e.g. the gravitational field from other stars when one study the pseudo-relativistic Hartree equation. Similar questions have been considered for optical solitons, certain water waves, and solitons in the Bose Einstein Condensates. Some of these results have recently been published. Our results on the soliton can be related also to nonlinear optics beyond the integrable one-dimensional solution.