Eggcrate radio frequency interposer

Patent metadata

Field	Value
Publication number	US-9974159-B2
Application number	US-201514944733-A
Country	US
Kind code	B2
Filing date	Nov 18, 2015
Priority date	Nov 18, 2015
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

An radio-frequency (RF) interposer enables low-cost, high-performance RF interconnection of two or more large-area printed wiring boards (PWBs). The RF interposer may be provided as a multi-port coaxial structure embedded in a metal (or metalized) carrier. The RF interposer may include one or more conductive shims having spring fingers to provide contact across air-gaps between a PWB RF ground plane and a ground plane of the RF interposer. Retractable pins may be used as the coaxial transmission line center conductors. The RF interposer may be provided as an N×M grid of unit cells each having one or more RF ports and a cavities to provide clearance for a PWB component.

First claim

What is claimed is:

1. A radio frequency (RF) interposer comprising:
a carrier structure having a first planar surface and a second planar surface opposite the first planar surface;
a plurality of RF ports supported by the carrier structure, each of the RF ports comprising a coaxial transmission line structure having a center conductor extending from carrier structure first planar surface to the carrier structure second planar surface and an outer conductor electrically separated from the center conductor by a dielectric insulator;
a first conductive shim having a plurality of spring fingers; and
a second conductive shim having a plurality of spring fingers,
wherein, when the first conductive shim is disposed over the carrier structure first planar surface and the second conductive shim is disposed over the carrier structure second planar surface, an electrical pathway is established between the first shim, outer conductors of ones of the plurality of RF ports, and the second shim;
wherein the spring fingers of said first conductive shim and the spring fingers of said second conductive shim project toward the surface of said carrier structure.

2. The RF interposer of claim 1 wherein the first and second conductive shims include a plurality of openings sized and positioned to expose center conductors of the RF ports when the first conductive shim is disposed over the carrier structure first planar surface and the second conductive shim is disposed over the carrier structure second planar surface.

3. The RF interposer of claim 2 wherein respective ones of said spring fingers of the first conductive shim are arranged around respective ones of the openings such that said spring fingers are in electrical contact with respective ones of the outer conductors of the RF ports.

4. The RF interposer of claim 1 wherein:
the carrier structure includes a plurality of cavities positioned and sized to provide clearance for components of a printed wiring board (PWB) mated to the RF interposer; and
each of the plurality of spring fingers of said first and second conductive shims are in electrical contact with an outer conductor of a corresponding one of said plurality of RF ports.

5. The RF interposer of claim 1 wherein ones of the plurality of RF port center conductors are provided as retractable pins.

6. The RF interposer of claim 1 wherein the carrier structure is provided as a conductive material or a non-conductive material having a conductive coating.

7. The RF interposer of claim 6 wherein the carrier structure comprises aluminum.

8. The RF interposer of claim 1 wherein the first and second conductive shims comprise copper sheets.

9. The RF interposer of claim 1 comprising a plurality of periodically arranged unit cells, wherein each of the unit cells includes a fixed number of the RF ports.

10. The RF interposer of claim 9 wherein the unit cells are arranged in a grid.

11. The RF interposer of claim 9 wherein the unit cells are arranged in a triangular lattice.

12. The RF interposer of claim 9 wherein each of the unit cells includes two of the RF ports.

13. The RF interposer of claim 9 wherein the carrier structure includes a plurality of cavities positioned and sized to provide clearance for components of a printed wiring board (PWB) mated to the RF interposer, wherein each of the unit cells includes one of the plurality of cavities.

14. The RF interposer of claim 1 further comprising a plurality of alignment pins extending perpendicular to the first planar surface.

15. The RF interposer of claim 1 wherein the spring fingers of said first and second conductive shims are in electrical contact with the outer conductors of ones of the plurality of RF ports such that the electrical pathway established between the first shim, outer conductors of ones of the plurality of RF ports and the second shim correspond to a ground signal path.

16. The RF interposer of claim 1 wherein:
the spring fingers of said first conductive shim and the spring fingers of said second conductive shim project toward the surface of said carrier structure; and
the spring fingers of said first and second conductive shims are in electrical contact with the outer conductors of ones of the plurality of RF ports such that the electrical pathway established between the first shim, the outer conductors of ones of the plurality of RF ports and the second shim correspond to a ground signal path.

Assignees

• Raytheon Co

Inventors

• Puzella Angelo M
• Francis John B
• Mercier Dennis W
• Sangiolo John
• Ackerman Mark
• Heinrich Ethan S

Classifications

• H05K2201/10378

  Interposers · CPC title

• H05K1/144

  Stacked arrangements of planar printed circuit boards · CPC title

• H05K1/183

  associated with components mounted in and supported by recessed areas of the PCBs · CPC title

• H05K1/0216

  Reduction of cross-talk, noise or electromagnetic interference (grounding H05K1/0215) · CPC title

• H01R12/523 Primary

  by an interconnection through aligned holes in the boards or multilayer board · CPC title