Dual-reflector omnidirectional antenna for MMDS base stations
DOI:
https://doi.org/10.1109/ICATT.1999.1236155Abstract
Multichannel Multipoint Distribution System (MMDS) along with cable net represent the most convenient way to distribute TV and radio signals over a small area. Asynchronous access to the Inter-net can also be realized via MMDS. MMDS base-stations, covering a circle area, employ antennas, that produce omnidirectional radiation patterns in the azimuth plane. Common methods of achieving a uniform azimuth distribution are using arrays of surface slots on a circular or coaxial waveguide, arrays of vibrators, etc. Another way is a dual-reflector omnidirectional antenna, which consists of a waveguide feed, sub- and main reflectors, shaped to produce the prescribed elevation pattern. The antenna axisymmetry along with properly designed feed ensure azimuthal omnidirectionality. Such antenna has a number of advantages: high gain, shaped elevation pattern, vertical and horizontal polarizations at the same time. TM01, TE01 as well as H11 excitation may be utilized.
A new mathematical model of such antennas, allowing VSWR calculation, has been given in [1]. In this paper the results of design, simulation and measurement of the dual-reflector omnidirectional antenna for MMDS (11.7–13.5 GHz) are presented.
References
Dubrovka, F.F.; Kim, O.S. A new mathematical model of omnidirectional dual-reflector antennas. Izvestiya VUZ. Radioelektronika, 1999, Vol. 42, No. 6, P. 3-16 [Radioelectronics and Communications Systems, 1999, Vol. 42, No. 6].
Galindo, V. Design of dual-reflector antennas with arbitrary phase and amplitude distributions. IEEE Trans., 1964, Vol. AP-12, No. 4, P. 403-408.
Dubrovka, F.F.; Dubrovka, R.F.; Kim, O.S. A highly efficient iterative method of diffraction synthesis of axially symmetric dual-reflector antennas for satellite information systems. Part 1: The theory. Izvestiya VUZ. Radioelektronika, 1998, Vol. 41, No. 7, P. 9-21 [Radioelectronics and Communications Systems, 1998, Vol. 41, No. 7, p. 5-13].
Norris, A.P.; Waddoup, W.D. A millimetric wave omnidirectional antenna with prescribed elevation shaping. Proc. of Int. Conf. on Antennas and Propagation, 1985. N.Y.: IEE, 1985, P. 141-145.
