Speaker: Prof. Vakur B. Ertürk, Bilkent University

Topic: "Incomplete-Leaf Multilevel Fast Multipole Algorithm for Multiscale Electromagnetics Problems"

Location: Middle East Technical University, Ankara, Turkey

Abstract: Fast Multipole Method (FMM) is selected as one of the 10 algorithms with the greatest influence on the development and practice of science and engineering in the 20th century, and its multilevel version, Multilevel Fast Multipole Algorithm (MLFMA), is currently among the most widely used and powerful methods in computational electromagnetics (CEM) in addition to its use in other fields such as chemistry, biology, and physics applications. However, when scattering from multi-scale (electromagnetic) applications are considered, for instance electrically small and structurally complicated antennas on large platforms, MLFMA may become considerably inefficient or inaccurate originating from the fact that it deploys fixed-size boxes at each and every level of the corresponding tree structure, which is not suited when use of a multi-scale meshing (i.e., highly nonuniform) is inevitable.  

In this talk, we will present our recent work on an efficient and versatile broadband MLFMA, which is capable of handling large multiscale electromagnetic problems with a wide dynamic range of mesh sizes. By invoking a novel concept of incomplete-leaf tree structures, where only the overcrowded boxes are divided into smaller ones for a given population threshold, versatility of using variable-sized boxes is achieved. Consequently, for geometries containing highly overmeshed local regions, the proposed method is always more efficient than the conventional MLFMA for the same accuracy, while it is always more accurate if the efficiency is comparable. Furthermore, in such a population-based clustering scenario, the error is controllable regardless of the number of levels.

Bio: Vakur B. Ertürk received the B.S. degree in electrical engineering from the Middle East Technical University, Ankara, Turkey, in 1993, and the M.S. and Ph.D. degrees from The Ohio-State University (OSU), Columbus, in 1996 and 2000, respectively. He is currently a Professor with the Electrical and Electronics Engineering Department, Bilkent University, Ankara. His research interests include the analysis and design of conformal antennas and arrays, wireless sensors for structural health monitoring, numerical techniques, printed circuits, scattering from and propagation over large terrain profiles. Dr. Ertürk served as the Secretary/Treasurer of the IEEE Turkey Section as well as the Turkey Chapter of the IEEE Antennas and Propagation, Microwave Theory and Techniques, Electron Devices and Electromagnetic Compatibility Societies. He was the recipient of the 2005 URSI Young Scientist and 2007 Turkish Academy of Sciences Distinguished Young Scientist Awards.

  Date and Time




  • Ankara, Ankara
  • Turkey


Prof. Vakur B. Erturk of Bilkent University


Incomplete-Leaf Multilevel Fast Multipole Algorithm for Multiscale Electromagnetics Problems



Address:Ankara, Ankara, Turkey