Antennas formed using multilayer ceramic substrates

• US 6,154,176 A
• Filed: 04/30/1999
• Issued: 11/28/2000
• Est. Priority Date: 08/07/1998
• Status: Active Grant

• Current Assignee: Kung Investment, LLC
• Original Assignee: Sarnoff Corporation (SRI International, Inc.)
• Inventors: Rosen, Arye, Geller, Bernard Dov, Perlow, Stewart Mark, Fathy, Aly
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): NGUYEN, HOANG V
• Application Number:
  US09/305,796
• Time in Patent Office: 578 Days
• Field of Search: 343/700 MS, 343/853, 343/846, 333/137, 333/239, 333/262
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 21/061 Two dimensional planar arrays
• CPC Class Codes: H01Q 9/0414 in a stacked or folded configuration

Abstract

An array antenna includes a first ceramic layer and a second ceramic layer. A metal layer is disposed between the first and second ceramic layers. A plurality of radiating elements are mounted on the first ceramic layer, and a plurality of control circuits are mounted on the second ceramic layer. The control circuits are coupled to the radiating elements through a plurality of conductive vias which feed through the metal layer. The array antenna may also include a switch having a plurality of poles formed in the second ceramic layer and coupled to one of the radiating elements through one or more conductive vias. A plurality of phase delay elements may be coupled at a first end to a signal source and coupled at a second end to the respective plurality of poles of the switch to provide phase-delayed signals. A waveguide may also be formed within the ceramic layers. Conductive vias or coaxial transmission lines may be used to connect elements within the array antenna.

Claims

1. An array antenna comprising:

a first ceramic layer and a second ceramic layer;

a metal layer disposed between the first and second ceramic layers;

a plurality of radiating elements mounted on the first ceramic layer; and

a plurality of control circuits mounted on the second ceramic layer and coupled to the radiating elements through a plurality of conductive vias which feed through the metal layer.

2. The array antenna of claim 1 wherein the radiating elements operate at a relatively high frequency, while the control circuits operate at a relatively low frequency.

3. The array antenna of claim 1 further comprising a power distribution network embedded in the first ceramic layer and coupled to the radiating elements.

4. The array antenna of claim 1 wherein the radiating elements are made of metal and are substantially circular in shape.

5. The array antenna of claim 1 further comprising a pair of shielding walls rising from a surface of the first ceramic layer opposite the metal layer to define a shielded channel separated from the radiating elements.

6. The array antenna of claim 5 further comprising a discrete circuit component mounted in the shielded channel.

7. The array antenna of claim 5 further comprising a passive circuit component mounted in the shielded channel.

8. The array antenna of claim 1 further comprising a ferrite layer disposed between the metal layer and the first ceramic layer to define a circulator.

9. The array antenna of claim 1 wherein the conductive vias are filled with silver.

10. The array antenna of claim 1 wherein a plurality of shielding vias are formed in the first ceramic layer.

11. The array antenna of claim 1 further comprising an electro-mechanical switch having a plurality of poles formed in the second ceramic layer and coupled to one of the radiating elements through one or more conductive vias.

12. The array antenna of claim 11 further comprising a plurality of phase delay elements coupled at a first end to a signal source and coupled at a second end to the respective plurality of poles of the switch, wherein the plurality of phase delay elements provide respective phase-delayed signals and the switch is activated to apply a selected one of the phase-delayed signals to the one radiating element.

13. An antenna comprising:

a first ceramic layer and a second ceramic layer;

metal layer disposed between the first and second ceramic layers;

a plurality of radiating elements mounted on the first ceramic layer;

a plurality of control circuits mounted on the second ceramic layer and coupled to the radiating elements through a plurality of conductive vias extending through the metal layer; and

a waveguide embedded in the first ceramic layer and coupled to the radiating elements through conductive vias extending through the metal layer to route signals to the radiating elements.

14. An array antenna comprising:

a first ceramic layer having a first feed element embedded therein;

a second ceramic layer having a second feed element embedded therein;

a radiating element disposed proximate the second ceramic layer opposite the first ceramic layer;

a first ground plane disposed between the first and second ceramic layers, and a second ground plane disposed between the second ceramic layer and the radiating element;

a first shielded coaxial transmission line which feeds through the first and the second ground planes to couple the first feed element to the radiating element; and

a second shielded coaxial transmission line which feeds through the second ground plane to couple the second feed element to the radiating element.

15. The array antenna of claim 14 wherein the first and second shielded coaxial transmission lines each include a coaxial inner conductor defined by a conductive via, and a coaxial shield surrounding and spaced apart from the coaxial inner conductor.

16. An antenna comprising:

a metal base layer;

a first ceramic layer stacked on top of the metal base layer;

a ground plane stacked on top of the first ceramic layer;

a second ceramic layer stacked on top of the ground plane;

a plurality of radiating elements mounted on top of the second ceramic layer;

a third ceramic layer stacked on top of the radiating elements and the second ceramic layer;

a plurality of parasitic radiating elements mounted on top of the third ceramic layer, each parasitic radiating element being proximate to and paired with a respective radiating element such that the pairs are capacitively coupled.

17. The planar antenna of claim 16 further comprising a distribution network disposed in the first ceramic layer and coupled to the radiating elements through a plurality of vias extending through the ground plane.

18. A planar antenna comprising:

a metal base layer;

a first ceramic layer disposed on top of the metal base layer;

a first ground plane disposed on top of the first ceramic layer;

a second ceramic layer disposed on top of the ground plane;

a second ground plane disposed on top of the second ceramic layer;

a third ceramic layer disposed on top of the second ground plane;

a plurality of radiating elements mounted on top of the third ceramic layer;

a first distributed network embedded in the first ceramic layer and coupled to the radiating elements through a plurality of vias extending through the first and second ground planes to provide a first signal having a first polarization to the radiating elements; and

a second distributed network embedded in the second ceramic layer and coupled to the radiating elements through a plurality of vias extending through the second ground plane to provide a second signal having a second polarization to the radiating elements;

whereby a radiated signal provided by the radiating elements may be controlled in polarity by controlling the first and second signals in magnitude.