Patent Application
20230066261
The present invention generally relates to radio frequency (RF) communications hardware. More particularly, the present invention relates to antennas and antenna feed systems.
Antennas, such as broadband parabolic reflectors, can be illuminated by a feed system, such as a log periodic dipole array (“LPDA”). For dual polarized applications, dual polarized LPDAs can be assembled with a common axis for lower frequencies. However, such an assembly becomes difficult as the frequency increases. For example, with known techniques used to construct dual polarized LPDAs, one or more performance characteristics are compromised, including, for example, cross-polarization and port-to-port isolation performance, particularly at higher frequencies.
Broadband parabolic reflectors can also be illuminated by dual polarized Vivaldi type feeds. However, these systems produce a return loss that is typically not adequate for some applications.
In view of the above, there is a continuing, ongoing need for improved antenna feed systems.
While this invention is susceptible of an embodiment in many different forms, there are shown in the drawings and will be described herein in detail specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention. It is not intended to limit the invention to the specific illustrated embodiments.
Embodiments disclosed herein can include a dual polarized antenna feed system and methods for operating and manufacturing such a system.
As best seen in
In some embodiments, the first single polarized antenna feed element 22 can include a LPDA, and the second single polarized antenna feed element 23 can include a LPDA. However, various other embodiments are also contemplated. For example, the first single polarized antenna feed element 22 and/or the second single polarized antenna feed element 24 can include a patch antenna, a waveguide horn, elements on a printed circuit board, and other antenna structures known in the art. Furthermore, in some embodiments, the dual polarized antenna feed system 20 can include mixed types of antenna structures where the first single polarized antenna feed element 22 has a different structure from the second single polarized antenna feed element 24.
In operation, the polarization filter 26 can act as a reflector to incident signals originating from the first single polarized antenna feed element 22 and can be transparent to incident signals originating from the second single polarized antenna feed element 23. In particular, as seen in
In some embodiments, relative angles and orientations of the first single polarized antenna feed element 22, the second single polarized antenna feed element 24, and the polarization filter 26 can be controlled to direct signal paths. For example, in some embodiments, the first axis on which the first single polarized antenna feed element 22 is oriented can be approximately 90° relative to the second axis on which the second single polarized antenna feed element 24 is oriented. Furthermore, the first axis can be approximately 45° relative to the polarization filter 26, and the second axis can be approximately 45° relative to polarization filter 26. In these embodiments, the incident signals originating from the first single polarized antenna feed element 22 can be directed towards the polarization filter 26 at a first angle relative to the polarization filter 26 and be reflected off of the polarization filter 26 at a second angle relative to the polarization filter such that the second angle can be perpendicular to the first angle and such that a redirected path of reflected signals can be parallel to a path of the incident signals originating from the second single polarized antenna feed element 24 and passing through the polarization filter 36.
In some embodiments, such as the one illustrated in
Embodiments described herein can also include a method for constructing the dual polarized antenna feed system 20. For example, in some embodiments, the method for constructing the dual polarized antenna feed system 20 can include arranging or positioning the first single polarized antenna feed element 22 on the first axis relative to the polarization filter 26 and so that the polarization of the first single polarized antenna feed element 22 is parallel to the plurality of conductors 32 and arranging or positioning the second single polarized antenna feed element 24 on the second axis relative to the polarization filter 26 and so that the polarization of the second single polarized antenna feed element 24 is orthogonal to the plurality of conductors 32.
Constructing the dual polarized antenna feed system 20 in this manner so that the first and second single polarized antenna feed elements 22, 24 are separated can provide for a simplified mechanical structure when compared with known dual polarized antenna feed systems. Furthermore, as seen in the graph of exemplary isolation between the first single polarized antenna feed element 22 and the second single polarized antenna feed element 24 illustrated in
Embodiments described herein can also include a method for operating the dual polarized antenna feed system 20. For example, in some embodiments, the method of operation can include receiving the incident signals originating from the first single polarized antenna feed element 22 at the polarization filter 26, receiving the incident signals originating from the second single polarized antenna feed element 24 at the polarization filter 26, reflecting the majority of the incident signals originating from the first single polarized antenna feed element 22 off of the polarization filter 26, and passing the majority of the incident signals originating from the second single polarized antenna feed element 24 through the polarization filter 26.
Although a few embodiments have been described in detail above, other modifications are possible. For example, other components may be added to or removed from the described systems, and other embodiments may be within the scope of the invention.
From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific system or method described herein is intended or should be inferred. It is, of course, intended to cover all such modifications as fall within the spirit and scope of the invention.
