Broadband antenna reflector for a circular-polarized planar wire antenna and method for producing said antenna reflector

A method for implementing an antenna reflector for a circular-polarized planar wire antenna capable of emitting electromagnetic radiation in two directions orthogonal to a plane of the circular-polarized planar wire antenna over a predetermined frequency band, the method comprising:

• determining, in a near-field region, an amplitude distribution of electromagnetic radiation emitted by the circular-polarized planar wire antenna in an absence of the antenna reflector for at least a first and a second sub-band of frequencies belonging to the predetermined frequency band,
• determining a shape and dimensions of a first reflection region of the antenna reflector designed to reflect, with a phase-shift of 180 degrees, an electric field of the electromagnetic radiation as a backward radiation whose frequency is included within the first sub-band of frequencies, in such a manner that the first reflection region is situated facing a region of the circular-polarized planar wire antenna where the electromagnetic radiation to be emitted by the circular-polarized planar wire antenna in the first sub-band of frequencies has a highest amplitude, at a distance allowing the electric field of the backward radiation to be reflected substantially in phase with a forward radiation of the electric field of the electromagnetic radiation, and
• determining a shape and dimensions of a second reflection region of the antenna reflector designed to reflect, with a phase-shift included between two values of an angle on either side of zero degrees, the electric field of the backward radiation whose frequency is included in the second sub-band of frequencies, in such a manner that the second reflection region is situated facing the region of the antenna where the electromagnetic radiation to be emitted by the circular-polarized planar wire antenna in the second sub-band of frequencies has the highest amplitude, at a distance allowing the electric field of the backward radiation to be reflected substantially in phase with the electric field of the forward radiation;
• wherein the first reflection region and the second reflection region are different and separated by a gap;
• and
• wherein each of the first reflection region and the second reflection region is distributed separately and concentrically around a center of the circular-polarized planar wire antenna.