Method of Synthesizing a Beam-Forming Device for the N-Beam and N-Element Array Antenna, for any N

Abstract

The possibility of forming a set of spatially dispersed and mutually orthogonal beams in an array antenna has been known long ago. The method for obtaining a device that forms a fan of beams for arrays with the number of elements and beams equal to was suggested by Butler. Realizing a fan of mutually orthogonal beams for arrays with any , was shown by us in "Synthesis of pattern forming networks" Radio Engineering and Electronic Physics, vol. 27, no. 7, pp. 28-35, 1982. The schemes of the corresponding devices for , 6 and 8 were also represented, however, the method for building a concrete scheme was described there without details. The present paper is dedicated to the procedure of synthesizing a beam-forming device based on the factorization of its transmission matrix, at this point, each factor represents a matched and decoupling hybrid. As a result, the beam-forming network is represented by a cascade connection of elementary matrices containing one hybrid or several 90 phase shifters. The procedure is illustrated using examples of synthesizing matrices for and having broadside beams, and also that for where the left and right beams are symmetrical as normally assumed for "Butler" matrices. Furthermore, the scheme with is compared with the corresponding "Butler" matrix.

Dual-polarized wideband multi-beam arrays in wireless communications

“…For N = 2, 4, and 8, the phase increments between antenna ports of the Butler matrix are well known and shown in Table I. By introducing the non-equal amplitude (i. e., not 3 dB) hybrid coupler (HC), the Butler matrix NxN with orthogonal beams can be realized for any N [3]. As shown in Table I, there is a broadside beam (i. e., zero phase increment) for odd number N. By subtracting a constant phase at antenna ports, a new set of the Butler matrix JxN, where J = N-1, is introduced and their corresponding phase increments are shown in the right column of Table I.…”

“…Due to its simplicity, fixed beam antennas are used widely for base station antennas and other antenna systems to enhance the antenna gain and reduce interferences. Dual polarization multibeam array, due to the additional polarization diversity, has been implemented globally for the increase of the system capacity and coverage [1]- [3]. In this paper, we introduce the design and implementation of the wideband multibeam dual polarization antenna array for wireless applications (1.71-2.36 GHz).…”

Design and Implementation of a 3 X 3 Orthogonal Beam-Forming Network for Pattern-Diversity Applications

“…While given a = b, the 180 • hybrid is a non-equi-amplitude one, and the output powers ratio is p = (a/b) 2 . In order to realize three orthogonal beams, the transmission block T of the scattering matrix represents a symmetrical unitary matrix as follows [9]:…”

“…Based on the factorization of the transmission matrix, the procedure of synthesizing the orthogonal BFN for N = 6, 8 and 9 orthogonal beams is described in [9]. Compared with the design procedure, the implementation of the orthogonal BFN is also important and difficult which is not discussed in [9].…”

“…Compared with the design procedure, the implementation of the orthogonal BFN is also important and difficult which is not discussed in [9].…”