Beam forming network for radiofrequency antennas

Abstract

The invention concerns a beam forming network for radiofrequency antennas and applying to the input signals a two-dimensional hexagonal discrete Fourier transform in order to control radiating elements for generating multiple beams. The number of inputs and outputs is equal to N.sub.t with N.sub.t =R.times.N.sup.2, R and N being integers. A first circuit layer comprises a row of N.sup.2 cells each having R inputs and R outputs, each cell receiving a signal present at one of said N.sub.t inputs and applying to the signals present at its R inputs a one-dimensional R.times.R discrete Fourier transform, and a second circuit layer comprises R independent sets of cells each having N inputs and N outputs, each set including a first row and a second row of N cells, each cell applying to the signals present at its N inputs a one-dimensional R.times.R discrete Fourier transform. The invention also concerns a hardware structure for a network of this kind.