Plane wave diffraction by a finite number of metal cylindrical rectangular strips (patches) periodically placed on a dielectric rod (DR) surface in azimuth direction is considered. The problem is solved by the Method of Moments (MoM) in the spectral domain using PieceWise Sinusoidal (PWS) basis functions. Topologies with a highly resonant behavior of the patch currents in both azimuth and longitudinal directions are considered. This includes topologies with 1, 2, or 3 patches that are nearly touching, in which case one can also view the topology as a slotted metal cylinder. For these slotted cylinders with one and two slots it is shown that 2D approximate analytical solutions based on the rigorous Riemann-Hilbert approach yield a good agreement with 3D MoM solutions for the natural frequency of the half wavelength resonance until the slot width reaches 40˚. It is found that in the 3D case the natural frequency of the half-wavelength resonance for gap coupled patches tends to zero when the slot is vanishing. The radar cross-section versus frequency, resonant current distributions on the patches and far fields are presented.
1. Chen, T., N. Bowler, and J. R. Bowler, "Analysis of arc-electrode capacitive sensors for characterization of dielectric cylindrical rods," IEEE Transactions on Instrumentation and Measurement, Vol. 61, No. 1, 233-240, 2012. doi:10.1109/TIM.2011.2157573
2. Svezhentsev, A. Ye., V. Volski, S. Yan, and G. A. E. Vandenbosh, "Shaped nanoantennas on cylindrical and planar substrate," Proc. of the 2017 IEEE First Ukraine Conference on Electrical and Computer Engineering (UKRCON), 650-654, Kiev, Ukraine, May 29-June 2, 2017.
3. Tretyakova, S. S., O. A. Trtyakov, V. G. Sologub, and V. P. Shestopalov, "Excitation of the open structure of the ``squirrel cell'' type by a charge moving in a circle," Journal of Technical Physics, No. 10, 1923-1927, 1967 (in Russian).
4. Shestopalov, V. P., Summatory Equations in the Modern Theory of Diffraction, 252, Naukova Dumka, Kiev, 1983.
5. Nosich, A. I. and V. P. Shestopalov, "Excitation of a partially shielded round dielectric rod by lumped sources," Soviet Physics - Technical Physics, Vol. 28, No. 12, 1421-1426, 1983.
6. Svezhentsev, A. Ye. and V. V. Kryzhanovskiy, "Patch shape influence upon radar cross section of a cylindrical microstrip antenna," Progress In Electromagnetic Research B, Vol. 15, 307-324, 2009. doi:10.2528/PIERB09050602
7. Svezhentsev, A. Ye., V. Kryzhanovskiy, and G. A. E. Vandenbosch, "Cylindrical microstrip array antennas with slotted strip-framed patches," Progress In Electromagnetic Research, Vol. 139, 539-558, 2013. doi:10.2528/PIER13031916
8. Svezhentsev, A. Ye., P. J. Soh, S. Yan, and G. A. E. Vandenbosch, "Green’s functions for probe-fed complex-shape cylindrical microstrip antennas," IEEE Transactions on Antennas and Propagation, Vol. 63, No. 3, 993-1003, 2015. doi:10.1109/TAP.2015.2389794
9. Schelkunoff, S. A., "Some equivalence theorems of electromagnetics and their application to radiation problems," Bell Syst. Tech. Journ., Vol. 15, 92, 1936. doi:10.1002/j.1538-7305.1936.tb00720.x
10. Harrington, R. F., Time-harmonic Electromagnetic Fields, McGraw-Hill Book Company, 1961.
11. Helmholtz, H., Theorie der Luftschwingungen in Rohren mit offenen Enden, Crelle, 1860.