Slotted waveguide antenna with a near‐field focused beam in one plane

Abstract

Abstract---A slotted waveguide providing a two dimensional near-field focused beam is presented in this paper. This antenna focuses the beam in the E-plane and provides a wide beam in the H-plane in order to illuminate a linear array, as reflect-or transmit-array antenna with a small width (100mm) and a very large length (1530mm) located in the near-field region. The simulated field distribution on the array is found to be in very good agreement with the measurement of a prototype at 9.41GHz.

Technologies for Near-Field Focused Microwave Antennas

“…When compared with printed antenna technology, waveguide antennas exhibit a better efficiency and higher power handling. Clauzier et al [70] designed and characterized a slotted waveguide antenna to be used as the feeder of a transmitarray of an X-band navigation radar, which is 10 cm wide and 153 cm long. To this end, I-shaped slots are realized in the narrow side of a rectangular waveguide, to get a 2D focusing effect in the -plane, with a larger beam in the -plane.…”

“…Full-wave simulation results for another NFF X-band slotted waveguide array have been presented in [71]. As in [70], the focusing phase profile has been implemented by proper positioning of the radiating slots, even though longitudinal slots are used instead of transverse slots. A set of 10 slotted waveguides have been arranged in a planar star configuration to achieve a 3D focal spot at the broadside direction.…”

A new method for the design of slot antenna arrays: Theory and experiment

“…The field variation across slots of various lengths were record and compared with the theoretical formulas (4) and (5), upon which they were found to agree. The MID model equations (2) and (3) were then used to predict the far field produced by the slots based on the excitation levels predicted by (4) and (5). The pattern obtained this way was compared with the far field produced by the fullwave solver.…”

“…This slotted waveguide was modeled by an array of 50 MIDs (5 MIDs for each slot). The amplitude and the phase for each infinitesimal dipole was determined with the help of (4) and (5). The far-field radiation patterns based on the analytical model and the one computed by full-wave solver (CST Microwave Studio) are compared in Fig.…”

“…Slotted waveguides have found many applications in radar and communication systems due to their low-profile design requirements, mechanical robustness, good efficiency, and the relative ease of realization compared with other conventional antenna arrays [3]- [5]. Early in the beginning of the slotted waveguide technology, methods have been proposed to determine the positions/orientations of the slots in order to achieve a given radiation pattern [3], [6].…”