Array guided surface waves on a finite planar array of dipoles with or without a grounded substrate

2006-08-01
The existence of array guided surface waves (AGSWs) on partially finite (finite x infinite) array of dipoles in air have been demonstrated earlier; the work in this paper extends this study to fully finite (finite x finite) planar arrays both in air and on a grounded material slab of infinite extent. Effects of AGSWs on scattering characteristics are examined and a ray interpretation is provided for the edge/corner excitation of AGSWs and conventional substrate surface waves.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION

Suggestions

Efficient parallelization of the multilevel fast multipole algorithm for the solution of large-scale scattering problems
Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2008-08-01)
We present fast and accurate solutions of large-scale scattering problems involving three-dimensional closed conductors with arbitrary shapes using the multilevel fast multipole algorithm (MLFMA). With an efficient parallelization of MLFMA, scattering problems that are discretized with tens of millions of unknowns are easily solved on a cluster of computers. We extensively investigate the parallelization of MLFMA, identify the bottlenecks, and provide remedial procedures to improve the efficiency of the imp...
Fast and accurate solutions of extremely large integral-equation problems discretised with tens of millions of unknowns
Gurel, L.; Ergül, Özgür Salih (Institution of Engineering and Technology (IET), 2007-04-26)
The solution of extremely large scattering problems that are formulated by integral equations and discretised with tens of millions of unknowns is reported. Accurate and efficient solutions are performed by employing a parallel implementation of the multilevel fast multipole algorithm. The effectiveness of the implementation is demonstrated on a sphere problem containing more than 33 million unknowns, which is the largest integral-equation problem ever solved to our knowledge.
Stabilization of integral-equation formulations for the accurate solution of scattering problems involving low-contrast dielectric objects
Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2008-03-01)
The solution of scattering problems involving low-contrast dielectric objects with three-dimensional arbitrary shapes is considered. Using the traditional forms of the surface integral equations, scattered fields cannot be calculated accurately if the contrast of the object is low. Therefore, we consider the stabilization of the formulations by extracting the nonradiating parts of the equivalent currents. We also investigate various types of stable formulations and show that accuracy can be improved systema...
Efficient solution of the electric-field integral equation using the iterative LSQR algorithm
Ergül, Özgür Salih (Institute of Electrical and Electronics Engineers (IEEE), 2008-01-01)
In this letter, we consider iterative solutions of the three-dimensional electromagnetic scattering problems formulated by surface integral equations. We show that solutions of the electric-field integral equation (EFIE) can be improved by employing an iterative least-squares QR (LSQR) algorithm. Compared to many other Krylov subspace methods, LSQR provides faster convergence and it becomes an alternative choice to the time-efficient no-restart generalized minimal residual (GMRES) algorithm that requires la...
Triple stub circuit topology as simultaneous insertion phase, amplitude and impedance control circuit for phased array applications
Unlu, M.; Demir, Şimşek; Akın, Tayfun (Institution of Engineering and Technology (IET), 2012-10-23)
This study shows that the well-known triple stub circuit topology can also be used for controlling the insertion phase and amplitude of a given signal simultaneously, as well as preserving its impedance transformation ability. The triple stub circuit topology, which is nothing but an extension of the conventional double stub loaded-line phase shifter, results in one more degree of freedom to its solution when it is solved for its insertion phase. This additional degree of freedom not only brings the impedan...
Citation Formats
H. Ö. Aydın Çivi, “Array guided surface waves on a finite planar array of dipoles with or without a grounded substrate,” IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, pp. 2244–2252, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35326.