Slotted Spherical Antenna With a Multi-Element Diaphragm in the Waveguide

Abstract

A problem of electromagnetic wave radiation by narrow slots cut in an end wall of a semi-infinite waveguide section into space above a perfectly conducting sphere is solved in a strict self-consistent formulation by the generalized method of induced magnetomotive forces (MMF). Inside the waveguide section, a reentrant cavity formed by the volume between a slotted diaphragm and the waveguide end wall is located. The waveguide is operating in the frequency range of a single-mode regime. The electrodynamic characteristics of this radiating system with the spherical screen of resonant dimensions are investigated numerically and experimentally. The possibility to develop the spherical antennas with a narrow-band frequency, energy, and spatial characteristics is substantiated.

Multiparameter Control of Energy Characteristics of Waveguide-Cavity Resonator-Slot Radiators

“…Currently, in the antenna-waveguide technology of millimeter and centimeter wavelengths, slotted radiators in flat and spherical surfaces are widely used as feeds for highly directional mirror and lens antennas [1][2][3][4][5], elements of inphase and scanning antenna arrays [6][7][8][9][10][11][12][13][14][15][16][17][18][19], as well as devices connections of electrodynamic volumes [20][21][22]. Single slotted radiators are characterized by a significant broadband, which in conditions, for example, of a complex electromagnetic environment, can lead to disruption of the operation of radio electronic systems (RES).…”

“…The formation of the required frequency-energy characteristics of slot radiators and coupling holes can be ensured, for example, by using combined (with dipoles, dielectric inserts, etc.) radiators [21, 22 and references therein], or by placing in the supply waveguide channel through cavity resonators, which, in turn, are band-pass and band-stop filters [4,16,23]. There are also other constructive solutions to this problem, namely: placement between the radiating slot and the connection slot (slots) the cavity resonator [11,18], and the presence of two closely spaced slots in the wall of the main waveguide makes it possible to significantly increase the value of the coupling coefficient in a narrow frequency band [14].…”