Electromagnetic Waves Scattering and Radiation by Vibrator-Slot Structure in a Rectangular Waveguide

Abstract

A problem of electromagnetic waves scattering and radiation by a structure, consisting of a narrow transverse slot in broad wall of rectangular waveguide and a vibrator with variable surface impedance, located inside the waveguide and interacting with one another, is solved. A solution of integral equations for electric current on the vibrator and equivalent magnetic current in the slot is derived by the generalized method of induced electro-magnetomotive forces. Conditions necessary for achievement of maximal slot radiation coefficient are defined. Effectiveness of impedance vibrators application to ensure required level of radiation by vibrator-slot structure in low profile rectangular waveguides is shown. Calculated and experimental plots of energy characteristics of the vibrator-slot structure for different vibrator placement relative to the slot and for various surface impedance dependencies upon the vibrator length are presented.

Electromagnetic Fields Excitation by a Multielement Vibrator-Slot Structures in Coupled Electrodynamics Volumes

“…The approach to the electrodynamic problem solution for the vibrator slot system which has been proven in [12,13], was extended to multielement vibrator-slot structure. The problem of electromagnetic fields excitation in the two electrodynamic volumes by finitedimensional material bodies was formulated in the most general form.…”

“…We have used three different distribution functions defining the imaginary part of vibrator impedance [4,13]: vibrators with inductive impedances (X S1(2) > 0), known to increase the vibrator electrical length, i.e., to increase λ res 1,2 as compared to casē Z S1(2) = 0, without decreasing a distance between the vibrators ends and the upper broad wall of the waveguide. This is very important for increasing the breakdown power for waveguide device as a whole.…”

“…Here J 0 1 (2) and J 0 3 are unknown current amplitudes, f 1(2) (s 1 (2) ) and f 3 (s 3 ) are distribution functions, obtained by solving equations for currents in a single vibrator and a slot by averaging method [21,22]. For the vibrator-slot structure excited by fundamental wave H 10 according to [13], we have…”

“…The equations system (11) was solved by the generalized method of induced EMMF [12,13], using approximate expressions for the currents J 1(2) (s 1(2) ) = J 0 1(2) f 1(2) (s 1(2) ) and J 3 (s 3 ) = J 0 3 f 3 (s 3 ). Here J 0 1 (2) and J 0 3 are unknown current amplitudes, f 1(2) (s 1 (2) ) and f 3 (s 3 ) are distribution functions, obtained by solving equations for currents in a single vibrator and a slot by averaging method [21,22].…”

“…The vibrators can be located either in a half-space over an infinite perfectly conducting plane in which a hole is cut for coupling with another electrodynamic volume (a half-space over an infinite perfectly conducting plane, a waveguide, a resonator etc.) [5][6][7][8] or in waveguide transmission lines [9][10][11][12][13]. A special place among the combined vibrator-slot structures occupies multielement systems [14][15][16][17][18][19][20].…”