Abstract The present invention relates to a quasi-optical frequency multiplexer which permits the bidirectional conversion of at least two intermediate angularly-distinct planar wavefronts, where each distinct planar wavefront corresponds to the wavelength of a separate radio channel, into a single directional wavefront by the use of a blazed diffraction grating mounted at the aperture of an antenna. More particularly, a single directional planar wavefront, comprising the wavelengths of at least two radio channels, is diffracted out of the blazed diffraction grating into at least two angularly-distinct intermediate planar wavefronts corresponding to the at least two radio channels. By properly placing separate feedhorns at the precise location on the focal plane of the antenna where each angularly-distinct intermediate planar wavefront is focused, the radio channels can be separated, or alternately combined in the reverse manner.
A frequency multiplexer comprising: a focusing means having a given focal plane and an aperture, the focusing means being capable of focusing each of at least two intermediate angularly distinct planar wavefronts in the aperture thereof towards a separate location on said given focal plane and transforming electromagnetic waves radiating from at least two locations on said given focal plane into separate intermediate angularly distinct planar wavefronts in the aperture thereof; a blazed diffraction grating, the grating being disposed in the aperture of the focusing means and in a manner to bidirectionally transform said at least two intermediate angularly distinct planar wavefronts into a single directional planar wavefront, each of said at least two intermediate angularly distinct wavefronts corresponding to signals of a separate wavelength; and at least two feedhorns, each feedhorn being associated with a separate one of said at least two intermediate angularly distinct planar wavefronts and disposed on said given focal plane at the location where the associated intermediate angularly distinct planar wavefront is focused by said focusing means.
Claim 2
Dependent Claim
172 words
A frequency multiplexer comprising: a focusing means having a given focal plane and an aperture, the focusing means being capable of focusing each of at least two intermediate angularly distinct planar wavefronts in the aperture thereof towards a separate location on said given focal plane and transforming electromagnetic waves radiating from at least two locations on said given focal plane into separate intermediate angularly distinct planar wavefronts in the aperture thereof; a blazed diffraction grating, the grating being disposed in the aperture of the focusing means and in a manner to bidirectionally transform said at least two intermediate angularly distinct planar wavefronts into a single directional planar wavefront, each of said at least two intermediate angularly distinct wavefronts corresponding to signals of a separate wavelength; and at least two feedhorns, each feedhorn being associated with a separate one of said at least two intermediate angularly distinct planar wavefronts and disposed on said given focal plane at the location where the associated intermediate angularly distinct planar wavefront is focused by said focusing means.
Claim 3
Dependent Claim
39 words
A frequency multiplexer according to claim 1 wherein the blazed diffraction grating is disposed to have the plane of incidence of the single directional planar wavefront substantially parallel to the long edges of the plurality of stepped reflecting planes.
Claim 4
Dependent Claim
14 words
A frequency multiplexer according to claim 1 wherein the focusing means is curved reflector.
Claim 5
Dependent Claim
15 words
A frequency multiplexer according to claim 1 wherein the focusing means is a collecting lens.