US-20260128519-A1 - FREQUENCY-DEPENDENT COUPLER FOR ANTENNA ARRAY POWER SHARING

US20260128519A1US 20260128519 A1US20260128519 A1US 20260128519A1US-20260128519-A1

Abstract

An antenna array has two columns of dipoles that are configured to radiate distinct signals. The top and bottom row of dipoles have a coupler that splits the power of each column such that each of the two dipoles at top and bottom radiate in both signals at a given power split ratio. The coupler provides for phase compensation so that the two radiated signals are phase aligned across the top and bottom row. Having the power shared at the top and bottom rows shifts the phase center away from the edge of the ground plane of the antenna’s reflector. The coupler is configured so that its coupling efficiency is greatest at the lowest frequency and least at its highest frequency. This improves the performance of the antenna array in the low frequencies while preserving antenna diversity between the two radiated signals.

Inventors

JIAQIANG ZHU
Wengang Chen

Assignees

John Mezzalingua Associates, LLC.

Dates

Publication Date: 20260507
Application Date: 20260102

Claims (11)

1 . A method for power sharing a plurality of RF signals in an antenna array having a first plurality of dipoles arranged in a first column, and a second plurality of dipoles arranged in a second column, wherein the first and second plurality of dipoles are configured to radiate in a frequency band, the method comprising: receiving a left dipole RF (Radio Frequency) signal; receiving a right dipole RF signal; splitting the left dipole RF signal into a first left dipole RF signal and a second left dipole RF signal, the first left dipole RF signal having a first power split magnitude and the second left dipole RF signal having a second power split magnitude; splitting the right dipole RF signal into a first right RF dipole signal and a second right RF dipole signal, the first right dipole RF signal having the first power split magnitude and the second right dipole RF signal having the second power split magnitude; coupling the first left dipole RF signal and the second right dipole RF signal to form a coupled left dipole RF signal; coupling the second left dipole RF signal and the first right dipole RF signal to form a coupled right dipole RF signal; outputting the coupled left dipole RF signal to a left dipole within the first plurality dipoles; and outputting the coupled right dipole RF signal to a right dipole within the second plurality of dipoles.
2 . The method of claim 1 , wherein the left dipole and the right dipole are in a single row.
3 . The method of claim 2 , wherein the single row is at a end of the first and second column.
4 . The method of claim 1 , wherein the coupling the first left dipole RF signal and the second right dipole RF signal comprises: conducting the first left dipole RF signal along a first trace within a left coupler segment; and conducting the second right dipole RF signal along a second trace within the left coupler segment, wherein the first trace and the second trace are parallel and separated by a gap.
5 . The method of claim 4 , wherein the left coupler segment comprises a lateral translation segment.
6 . The method of claim 4 , further comprising terminating the second right dipole RF signal at a load disposed at an end of the left coupler segment.
7 . The method of claim 4 , wherein the first trace comprises a first width and the second trace comprises a second width, wherein the first width is greater than the second width.
8 . The method of claim 1 , wherein the coupling the first left dipole RF signal and the second right dipole RF signal comprises coupling at a higher efficiency and a lower frequency end of the frequency band.
9 . The method of claim 8 , wherein the frequency band comprises a Low Band.
10 . The method of claim 1 , wherein the first power split magnitude and the second power split magnitude comprise a power split ratio, wherein the power split radio is 70/30.
11 . The method of claim 1 , wherein splitting the left dipole RF signal into a first left dipole RF signal and a second left dipole RF signal comprises: conducting the first left dipole RF signal along a first meandering trace; and conducting the second left dipole RF signal along a second meandering trace, wherein the first meandering trace and the second meandering trace are configured to provide phase alignment.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a Continuation of U.S. Application No. 18/690,015 filed on March 7, 2024, which is a National Stage Application of International Application No. PCT/US24/14079 filed on February 1, 2024, which claims the benefit of U.S. Provisional Application No. 63/482,602, filed on February 1, 2023, all of which are incorporated by reference in their entirety herein. Multiport and multiband antennas have seen a steady increase in demand and complexity. The current demand from the industry is for multiband antennas that operate in the low band (LB)(617-860 MHz), mid band (MB)(1695-2690 MHz), C-Band and CBRS (Citizens Broadband Radio Service)(3.4-4.2 GHz). For each of these bands, antennas are required to operate with multiple signals. In the case of the low band, a common design requirement is for the antenna to have four dedicated ports, whereby the antenna may be configured with two independent columns of LB radiators, with each LB radiator configured to transmit and receive two independent signals, each at a different polarization (e.g., +/- 45 degrees). Further complicating this is the demand that the multiband antenna be as narrow as possible to minimize wind loading. FIG. 1 illustrates a four-port LB array 100 in a multiband antenna. LB array 100 has a reflector 105 on which are disposed two columns (two linear arrays) of LB radiators 110. Each column of LB radiators is fed two RF (Radio Frequency) signals, one per polarization. In the illustrated example, the left column of LB dipoles 110 is fed two RF signals, from ports 115a and 115b; and the right column of LB dipoles 110 is fed two RF signals, from powers 120a and 120b. Each column of LB radiators 110 has a phase center 132 or 135. In a typical antenna design, the space between the two columns of LB dipoles 110 may be reserved for subarrays of MB and/or C-Band dipoles (not shown) that may be disposed on reflector 105. Also not shown in FIG. 1 is a phase shifter or Remote Electrical Tilt (RET) mechanism that provides differential phasing to the LB dipoles 110 in each column to provide for tilting of the radiated beam in the vertical plane. The RET mechanism is omitted herein for simplifying the diagram as it is not pertinent to the description of antenna array 100. As mentioned earlier, there is demand to reduce the width of reflector 105 to make the antenna as narrow as possible to mitigate wind loading. In response, a distance 160 from the outer edge of reflector 105 to phase center 135 may be narrow to where it affects the gain pattern of the LB dipoles 110. Accordingly, what is needed is a multiport LB antenna array that provides for improved performance as well as a narrow reflector. SUMMARY OF THE INVENTION An aspect of the present disclosure involves an antenna array. The antenna array comprises a reflector plate; a first column (e.g., a first linear array) of dipoles disposed on the reflector plate; a second column (e.g., a second linear array) of dipoles disposed on the reflector plate, wherein the first column of dipoles and the second column of dipoles are arranged to form a top row of dipoles and a bottom row of dipoles, where in the dipoles are configured to radiate in a frequency band; a top coupler coupled to a top pair of dipoles in the top row of dipoles; and a bottom coupler coupled to a bottom pair of dipoles in the bottom row of dipoles, wherein a first component of the top coupler and a first component of the bottom coupler are configured to receive a first signal and a second signal, to provide a phase compensation for the first signal and the second signal, and to couple the first signal and the second signal into a first output signal and a second output signal, wherein the first output signal is a mix of the first signal and the second signal at a first power ratio, and the second output signal is a mix of the first signal and the second signal at a second power ratio, wherein a second component of the top coupler and a second component of the bottom coupler are configured to receive a third signal and a fourth signal, to provide a phase compensation for the third signal and the fourth signal, and to couple the third signal and the fourth signal into a third output signal and a fourth output signal, wherein the third output signal is a mix of the third signal and the fourth signal at a third power ratio, and the fourth output signal is a mix of the third signal and the fourth signal at a fourth power ratio. The top coupler and the bottom coupler are configured to couple the aforementioned receive signals at a first efficiency corresponding to a low frequency of the frequency band and at a second efficiency corresponding to a high frequency of the frequency band. It should be noted that the terms “top” and “bottom” are used for ease of discussion and are not intended to reflect a relative vertical position. One skilled in the art would recognize that the term “top” and “bottom” c