Tools for Synthesis of Antennas and Sensors Project of Technology - PowerPoint PPT Presentation

Tools for Synthesis of Antennas and Sensors Project of Technology Agency of the Czech Republic Miloslav ˇ Capek & Project team 1 Department of Electromagnetic Field CTU in Prague, Czech Republic miloslav.capek@fel.cvut.cz Prague, Czech Republic March 15, 2016 1 Results you will see in this presentation are collective work of the whole project team. ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 1 / 70

Motivation 1 Source Concept 2 What is the source concept? Selected applications of the source concept Characteristic mode decomposition 3 4 About the project Project infrastructure 5 6 AToM architecture AToM – Closer investigation AToM’s – Features Integration into Visual CEM (ESI Group) 7 Conclusions 8 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 2 / 70

Motivation analysis Feeding Point Antenna characteristics  0 -5 s 11 [ dB] -10 -15 Q max = 7 -20 electric current f 0 Perfect Electric Conductor synthesis Antenna analysis × antenna synthesis. ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 3 / 70

Source Concept What is the source concept? Source Concept What is actually the Source Concept? It can be observed that . . . Perspective ◮ an antenna is topol- ogy and completely represented geometry by a source current, HPC, ◮ all parameters can be Modal de- algorithm compositions efficiency inferred from a source current, ◮ any proper int.-diff. Source Concept operator can be decomposed into modes Heuristic Integral and or can be inverted, or convex variational optimization methods ◮ spatial decomposition of current is possible. Sketch of main fields of the source concept. ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 4 / 70

Source Concept Selected applications of the source concept Source Concept Applications: Characteristic Modes ◮ characteristic modes (CMs) W W decomposition 2 J 1 J 2 X J = λ R J (1) • other useful decompositions Modes J 1 and J 2 are depicted. � J = α m J m (2) m M � J m , E � ◮ CMs are excellent for pattern synthesis � J = J m or feeding network synthesis 3 1 + λ m m =1 2 R. F. Harrington and J. R. Mautz. “Theory of Characteristic Modes for Conducting Bodies”. In: IEEE Trans. Antennas Propag. 19.5 (1971), pp. 622–628. doi : 10.1109/TAP.1971.1139999 3 R. F. Harrington and J. R. Mautz. “Pattern Synthesis for Loaded N-Port Scatterers”. In: IEEE Trans. Antennas Propag. 22.2 (1974), pp. 184–190. doi : 10.1109/TAP.1974.1140785 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 5 / 70

Source Concept Selected applications of the source concept Source Concept Applications: Structural Decomposition ◮ similar to structural decomposition in W A W B mechanical engineering ◮ to decide what part of a radiator stores J ( r A ) J ( r B ) significant portion of energy / radiates well 4 Division of Ω into two parts. ◮ excellent for synthesis of reflect arrays 5 ◮ combination with CM: sub-structure K modes 6 � J = J k k =1 4 M. Capek et al. “The Measurable Q Factor and Observable Energies of Radiating Structures”. In: IEEE Trans. Antennas Propag. 62.1 (2014), pp. 311–318. doi : 10.1109/TAP.2013.2287519 5 J. Ethier. “Antenna Shape Synthesis Using Characteristic Mode Concepts”. PhD thesis. University of Ottawa, 2012 6 J. L. T. Ethier and D.A. McNamara. “Sub-structure characteristic mode concept for antenna shape synthesis”. In: Electronics Letters 48.9 (2012), pp. 471–472. issn : 0013-5194. doi : 10.1049/el.2012.0392 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 6 / 70

Source Concept Selected applications of the source concept Source Concept Applications: Optimization W max ◮ both single- and multi-objective W 0 W final optimization can be utilized in order to W max obtain best antenna performance ◮ many objectives can be subjects of convex optimization 7 Optimization of antenna’s shape. • F ( J , J ) has to be positive single-objective optim.: semi-definite 8 { y j } = min { x i } F ( J ) • convex optimization does not result in specific design, only minimizes given multi-objective optim.: convex function { y j } = min { x i } {F j ( J ) } 7 M. Gustafsson and S. Nordebo. “Optimal antenna currents for Q, superdirectivity, and radiation patterns using convex optimization”. In: IEEE Trans. Antennas Propag. 61.3 (2013), pp. 1109–1118. doi : 10.1109/TAP.2012.2227656 8 S. Boyd and L. Vandenberghe. Convex Optimization . Cambridge University Press, 2004 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 7 / 70

Source Concept Selected applications of the source concept Source Concept Applications: Advanced Post-processing VG 2A VG 2B ◮ any antenna parameter can be defined by functional containing current(s) VG 1 ◮ recently derived: • radiation efficiency without IBC 9 Feeding network synthesis. • measurable Q Z factor 10 β m,n = ℜ { α m α ∗ n } • energies for sub-wavelength radiators 11 ( ka < 1) where: • no matter if modal / structural / total α m = � J m , E � current is substituted 1 + λ m 9 M. Capek, J. Eichler, and P. Hazdra. “Evaluation of Radiation Efficiency from Characteristic Currents”. In: IET Microw. Antennas Propag. 9.1 (2015), pp. 10–15. doi : 10.1049/iet-map.2013.0473 10 M. Capek et al. “The Measurable Q Factor and Observable Energies of Radiating Structures”. In: IEEE Trans. Antennas Propag. 62.1 (2014), pp. 311–318. doi : 10.1109/TAP.2013.2287519 11 G. A. E. Vandenbosch. “Reactive Energies, Impedance, and Q Factor of Radiating Structures”. In: IEEE Trans. Antennas Propag. 58.4 (2010), pp. 1112–1127. doi : 10.1109/TAP.2010.2041166 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 8 / 70

Source Concept Selected applications of the source concept Source Concept Applications: Fundamental Bounds and Optimal Currents ◮ optimal current can be found 12 A n J n = ξ n B J n (3) ◮ optimal (minimal / maximal) • quality factor Q • D/Q ratio • radiation efficiency η rad • antenna gain G • other parameters. . . ◮ additional constraint of current resonance can be enforced Optimal Q on a spherical shell. 2 X ′ I n = Q n RI n 12 M. Capek and L. Jelinek. “Optimal Composition of Modal Currents For Minimal Quality Factor Q”. . In: (2016). arXiv:1602.04808,L. Jelinek and M. Capek. “Optimal Currents on Arbitrarily Shaped Surfaces”. In: (2016). arXiv:1602.05520 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 9 / 70

Source Concept Selected applications of the source concept Design of optimal antenna ◮ The source concept was recently utilized for so-called optimal antenna design. Source Concept • see e.g. recent papers by M. Cismasu and M. Gustafsson 13 or by J. Ethier and D. McNamara 14 Design of Op- AToM timal Antenna ◮ To this purpose, it is beneficial to have a fast prototyping environment with partially open-source code. Antenna Synthesis 13 M. Cismasu and M. Gustafsson. “Antenna Bandwidth Optimization With Single Freuquency Simulation”. In: IEEE Trans. Antennas Propag. 62.3 (2014), pp. 1304–1311 14 J. L. T. Ethier and D. A. McNamara. “Antenna Shape Synthesis without Prior Specification of the Feedpoint Locations”. In: IEEE Trans. Antennas Propag. 62.10 (2014), pp. 4919–4934. doi : 0.1109/TAP.2014.2344107 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 10 / 70

Source Concept Selected applications of the source concept Design of optimal antenna ◮ The source concept was recently utilized for so-called optimal antenna design. Source Concept • see e.g. recent papers by M. Cismasu and M. Gustafsson 13 or by J. Ethier and D. McNamara 14 Design of Op- AToM timal Antenna ◮ To this purpose, it is beneficial to have a fast prototyping environment with partially open-source code. Antenna Synthesis The optimal antenna design leads at least to a partial antenna synthesis! 13 M. Cismasu and M. Gustafsson. “Antenna Bandwidth Optimization With Single Freuquency Simulation”. In: IEEE Trans. Antennas Propag. 62.3 (2014), pp. 1304–1311 14 J. L. T. Ethier and D. A. McNamara. “Antenna Shape Synthesis without Prior Specification of the Feedpoint Locations”. In: IEEE Trans. Antennas Propag. 62.10 (2014), pp. 4919–4934. doi : 0.1109/TAP.2014.2344107 ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 10 / 70

Characteristic mode decomposition Characteristic mode decomposition 1 Motivation 2 Source Concept What is the source concept? Selected applications of the source concept 3 Characteristic mode decomposition 4 About the project 5 Project infrastructure 6 AToM architecture AToM – Closer investigation AToM’s – Features 7 Integration into Visual CEM (ESI Group) 8 Conclusions ˇ Capek et al. Tools for Synthesis of Antennas and Sensors 11 / 70