Steerable antenna assembly utilizing a dielectric lens

Patent metadata

Field	Value
Publication number	US-10291312-B2
Application number	US-201815984202-A
Country	US
Kind code	B2
Filing date	May 18, 2018
Priority date	Aug 24, 2016
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

A steerable antenna assembly (“SAA”) for receiving a plurality of incident radio frequency (“RF”) signals at a plurality of incident angles is disclosure. The SAA includes an approximately spherical dielectric lens (“SDL”), a waveguide aperture block (“WAB”), a switch aperture matrix (“SAM”), and a radial aperture combiner (“RAC”). The SDL receives and focuses the plurality of incident RF signals creating a plurality of focused RF signals at a plurality of focal points approximately along the back surface of the SDL. The WAB is positioned adjacent to the back surface of the SDL and receives the plurality of focused RF signals. The SAM electronically steers a beam of a radiation pattern produced by the SAA and switch between the pluralities of focused RF signals based on electronically steering the beam. The RAC produces a received RF signal from the plurality of focused RF signals.

First claim

What is claimed is:

1. A user terminal ( 100 ) comprising:
a steerable antenna assembly “SAA” ( 118 ) for receiving a plurality of incident radio frequency “RF” signals ( 230 ) at a plurality of incident angles ( 232 ), the SAA ( 118 ) including
an approximately spherical dielectric lens “SDL” ( 218 ) having
a front surface ( 226 ) and
a back surface ( 228 ),
wherein the SDL ( 218 ) is configured to receive and focus the plurality of incident RF signals ( 230 ) to create a plurality of focused RF signals at a plurality of focal points approximately along the back surface ( 228 ) of the SDL ( 218 ) and
wherein the plurality of focal points have positions along the back surface ( 228 ) of the SDL ( 218 ) that correspond to the plurality of incident angles ( 232 ) of the plurality of incident RF signals ( 230 ),

a waveguide aperture block “WAB” ( 220 ) positioned adjacent to the back surface ( 228 ) of the SDL ( 218 ),
wherein the WAB ( 220 ) is in signal communication with the back surface ( 228 ) of the SDL ( 218 ) and
wherein the WAB ( 220 ) is configured to receive the plurality of focused RF signals,

a switch aperture matrix “SAM” ( 222 ) in signal communication with the WAB ( 220 ),
wherein the SAM ( 222 ) is configured to electronically steer a ( 114 ) beam of a radiation pattern produced by the SAA ( 118 ), and
wherein the SAM ( 222 ) is also configured to switch between the plurality of focused RF signals based on electronically steering the beam ( 114 ), and

a radial aperture combiner “RAC” ( 224 ) in signal communication with the SAM ( 222 ),
wherein the RAC ( 224 ) is configured to produce a received RF signal from the plurality of focused RF signals;

an RF modem ( 200 ) in signal communication with the SAA ( 118 ), wherein the RF modem ( 200 ) is configured to receive the RF signal and demodulate the received RF signal to produce a received base-band signal ( 248 ); and
a controller ( 202 ) in signal communication with the SAA ( 118 ) and the RF modem ( 200 ),
wherein the controller ( 202 ) is configured to control
the RF modem ( 200 ) and
the SAM ( 222 ) to electronically steer the beam ( 114 ).

2. The user terminal ( 100 ) of claim 1 , wherein the SDL has at least one of:
a shape that is approximately a sphere or an oblate spheroid;
a sphericity variation that is less than approximately 0.01 wavelength of an operating RF frequency of the SAA;
a diameter of approximately 152.4 mm;
a dielectric constant approximately between 2 and 5; and
a gradient of decreasing refractive index radially out from a center of the SDL.

3. The user terminal ( 100 ) of claim 2 , wherein the SDL consists of a material selected from the group consisting of a thermoset plastic, a polycarbonate, a cross-linked polystyrene copolymer, and Polytetrafluoroethylene “PTFE”.

4. The user terminal ( 100 ) of claim 2 , wherein the SDL is a Luneburg lens.

5. The user terminal ( 100 ) of claim 1 , wherein the WAB ( 220 ) includes
a concave inner surface ( 238 ) positioned adjacent to the back surface ( 228 ) of the SDL ( 218 ) and
a conformal aperture array antenna “CAA” ( 304 ) along the concave inner surface ( 238 ),
wherein the CAA ( 304 ) is in signal communication with the back surface ( 228 ) of the SDL ( 218 ) and
wherein the CAA ( 304 ) includes a plurality of aperture elements ( 306 ( 1 ), 306 ( 2 ), 306 ( 3 ), 306 ( 4 ), 306 ( 5 ), 306 ( 6 ), and 306 ( 7 )).

6. The user terminal ( 100 ) of claim 5 ,
wherein the WAB ( 220 ) includes a plurality of waveguides ( 312 ) in signal communication with the CAA ( 304 ),
wherein each waveguide ( 314 ( 1 )- 314 ( 7 )) of the plurality of waveguides ( 312 ) includes a waveguide aperture in signal communication with the CAA ( 304 ), and
wherein each waveguide aperture of each waveguide ( 314 ( 1 )- 314 ( 7 )) of the plurality of waveguides ( 312 ) corresponds to an aperture element ( 306 ( 1 )- 306 ( 7 )) of the plurality of aperture elements of the CAA ( 304 ).

7. The user terminal ( 100 ) of claim 6 ,
wherein each aperture element of the CAA is an elliptical aperture and
wherein each waveguide aperture of the each waveguide of the plurality of waveguides is a correspondingly elliptical aperture.

8. The user terminal ( 100 ) of claim 7 ,
wherein the each elliptical aperture element of the CAA is a circular aperture and
wherein each elliptical aperture of the each waveguide of the plurality of waveguides is a correspondingly circular aperture.

9. The user terminal ( 100 ) of claim 8 ,
wherein the plurality of waveguides ( 312 ) includes a sub-plurality of waveguides and
wherein each waveguide of the sub-plurality of waveguides includes
a waveguide length ( 900 ),
a waveguide directional transition ( 904 ), and
a waveguide transition ( 906 ) from the circular aperture to a rectangular waveguide.

10. The user terminal ( 100 ) of claim 9 ,
wherein the SDL has a center ( 604 ),
wherein each waveguide ( 314 ( 1 )- 314 ( 7 )) of the plurality of waveguides ( 312 ) also includes a waveguide input-output “IO” port ( 316 ( 1 )- 316 ( 7 )),
wherein each waveguide aperture is aligned with the center of the SDL,
wherein each waveguide IO port is aligned the other waveguide IO ports, and
wherein each waveguide IO port is in signal communication with the SAM.

11. The user terminal ( 100 ) of claim 10 , wherein each waveguide is a solid-state waveguide.

12. The user terminal ( 100 ) of claim 10 ,
wherein the SAM includes a plurality of selectively activated switches ( 1000 ( 1 ), 1000 ( 2 ), 1000 ( 3 ), and 1000 (N)),
wherein each selectively activated switch ( 1000 ( 1 ), 1000 ( 2 ), 1000 ( 3 ), and 1000 (N)) of the plurality of selectively activated switches ( 1000 ( 1 ), 1000 ( 2 ), 1000 ( 3 ), and 1000 (N)) is in signal communication with a corresponding waveguide ( 314 ( 1 ), 314 ( 2 ), 314 ( 3 ), 314 ( 4 ), 314 ( 5 ), 314 ( 6 ), and 314 ( 7 )) from the plurality of waveguides ( 312 ) of the WAB ( 220 ) and the RAC ( 224 ), and
wherein each selectively activated switch ( 1000 ( 1 ), 1000 ( 2 ), 1000 ( 3 ), and 1000 (N)) is configured to conduct or block a waveguide 314 ( 1 ), 314 ( 2 ), 314 ( 3 ), 314 ( 4 ), 314 ( 5 ), 314 ( 6 ), and 314 ( 7 )) output signal from the corresponding waveguide IO port ( 316 ( 1 ), 316 ( 2 ), 316 ( 3 ), 316 ( 4 ), 316 ( 5 ), 316 ( 6 ), and 316 ( 7 )) to the RAC ( 224 ).

13. The user terminal ( 100 ) of claim 12 , wherein the each selectively activated switch includes a switching device selected from the group consisting of a PIN diode, latching ferrite switch, liquid crystal valve “LCV”, coaxial waveguide switch, and an RF isolator.

14. The user terminal ( 100 ) of claim 13 , further including a stepper motor ( 1200 ) operatively coupled with the WAB ( 220 ) and configured to selectively rotate the WAB and SDL based on a control signal from a controller ( 202 ).

15. The user terminal ( 100 ) of claim 14 ,
wherein the RAC is a radial combiner in signal communication with each waveguide output port and
wherein the RAC is configured to produce the received RF signal with either left-hand circular polarization “LHCP” or right-hand circular polarization “RHCP”.

16. The user terminal ( 100 ) of claim 1 ,
wherein the SAA is a reciprocal device,
wherein the SDL produces a transmitted RF signal from a received input RF signal at the RAC,
wherein the transmitted RF signal has a transmitted beam of the radiation pattern, and
wherein the SAM is configured to electronically steer the transmitted beam.

17. The user ter

Assignees

• Boeing Co

Inventors

• Savage Larry L
• Thacker Corey M

Classifications

• H01Q1/241

  used in mobile communications, e.g. GSM (H01Q1/247, H01Q1/248 take precedence) · CPC title

• H01Q3/34

  by electrical means (active lenses or reflecting arrays H01Q3/46) · CPC title

• H01Q1/28

  Adaptation for use in or on aircraft, missiles, satellites, or balloons · CPC title

• H01Q15/08 Primary

  formed of solid dielectric material · CPC title

• H04B7/0874 Primary

  using subgroups of receive antennas · CPC title