A.N. Shurkhovetsky – Leading Design Engineer, JSC «Taganrog Scientific Research Institute of Communications»
A.V. Alpatova – Ph.D.(Eng.), Senior Research Scientist, JSC «Taganrog Scientific Research Institute of Communications»
Wide-band multibeam antenna array (MAA) of millimeter range with overlapping 1,5 on basis of wavequide Rotman lens for working sector angles ±45° by number of beams radiation pattern (RP) equal 8 is calculated.
The period of array was choosed d = 4,0 mm for provision of absence of diffraction lobe of RP MAA in full sector of working angles.
The open end of rectangular waveguide with cutset 7,2×3,0 mm (horizontal polarization) was use as radiating elements of MAA. RP of rectangular waveguide with cutset 7,2×3,0 mm can provide angle sectors on azimuth ±45°.
Array of radiators and Rotman lens were performed as milled integrated construction for minimization of loss and processability.
The height of lens is h = 10 mm, when variance of phase velocity in frequency range is 12%.
The synthesis of contour of lens was performed on basis of set-up parameters of RP of geometrical optics method.
RP of MAA was calculated for synthesis contour in optical approaching by working frequency range.
The 3D solid model of MAA was designed.
Full-wave analusis of MAA 3D model were carried finite-integratiom technique method.
This paper introduces the calculation data of distribution of electric field in lens, frequency dependence of voltage standing wave ratio (VSWR) of beams outputs of MAA, results of electrodynamic modeling of 3D RP of beams of MAA, RP of MAA (gain coefficient) in azimuthal plane.
Efficiency of MAA was estimated. The calculated values of coefficient of efficiency in frequency range are:
from 28% to 38% for extreme beams, this is from 5,5 to 4,2 dB of loss;
from 50% to 60% for mean beams, this is from 3,0 to 2,2 dB of loss.
Design of MAA was maked from aluminum alloy D16, overall dimensions are 270×200×25 mm, mass is 2,7 kg. Port size of beam output and input of test signal correspond to standard flange of rectangular wave guide with cutset 7,2×3,4 mm.
Measure of VSWR, PR and transmission factor between input of signal injector (SI) and output MAA was performed. VSWR is less than 1,6, width of PR in working range is from 13,0° to 22,0°, maximum of PR MAA beams variation is from 5,2 to 8,6 dB in working frequency range.
Frequency flatness of transmission factor between input SI and central output MAA is 4 dB. Frequency flatness of transmission factor between input SI and extreme output MAA is 6 dB.
- Rotman W., Turner R. Wide-angle microwave lens for line source applications // IEEE Trans. Antennas Propagat. 1963. V. AP-11. № 6. P. 623−632.
- Hansen R.C. Design Trades for Rotman Lenses // IEEE Trans. Antennas Propagat. 1991. V. 39. № 4. P. 464−472.
- Suarez F.C., Mendez D.N., Baquero-Escudero M. Rotman lens with ridge gap waveguide technology for millimeter wave applications // Proceedings of the 7th European Conference on Antennas and Propogation (EuCAP). 2013. P. 4006−4009.
- Nussler D., Fuchs H.H., Brauns R. Rotman Lens for the millimeter wave frequency range // Proceedings of the 37th European Microwave Conference (EuMA). 2007. P. 696−699.
- Pourahmadazar J., Denidni T.A. Multi-beam Tapered Slot Antenna Array Using Substrate Integrated Waveguide Rotman Lens // Proceedings of the 45th European Microwave Conference (EuMA). 2015. P. 1457−1450.
- Rajabalian M., Zakeri B. An Implemented Non-Focal Rotman Lens // Proceedings of the 45th European Microwave Conference (EuMA). 2015. P. 1415−1418.
- Ruchenkov V.A., Sestroreczkij B.V., Klimov K.N. Primenenie ploskoj mnogoluchevoj linzy’ Rotmana v kachestve diagrammoobrazuyushhego ustrojstva fazirovannoj antennoj reshetki // Radiotexnika i e’lektronika. 2005. T. 50. № 1. S. 5−13.