Surface wave coupler

• US 20110133867A1
• Filed: 12/08/2009
• Published: 06/09/2011
• Est. Priority Date: 12/08/2009
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Worstell, Harry R., Miller, Robert R. II
• Granted Patent: US 8,212,635 B2
• Time in Patent Office: Days
• US Class Current: 333/240
• CPC Class Codes: H01P 3/06 Coaxial lines
• CPC Class Codes: H01P 5/12 Coupling devices having more than two ports H01P5/04 takes precedence

Abstract

The RF signal generated by a ZigBee radio on the outside of a building structure is conveyed to the interior of the building by guiding it along an electric cable bundle that passes through the building'"'"'s wall to supply domestic electric power to the interior of the structure. The RF signal is launched by a unique coupler comprising a pair of insulated foil conductors.

Claims

1. Apparatus comprising

an electrical power cable having a least one phase conductor and a conductive shield that surrounds the at least one conductor, and

a coupler surrounding the at least one phase conductor, a portion of the coupler but less than all of the coupler, also surrounding the shield, the coupler comprising at least first and second conductive layers that are insulated from one another, are insulated from the phase conductor and are insulated from the shield.

2. The apparatus of claim 1 wherein the first conductive layer surrounds the cable, an insulation layer surrounds the first conductive layer and the second conductive layer surrounds the insulation layer.

3. The apparatus of claim 3 wherein the second conductive layer is connected to ground and wherein the coupler is configured to launch, onto the electrical power cable in response to a signal applied to the first conductive layer, an electromagnetic signal having a propagation mode that is substantially a surface wave propagation mode.

4. The apparatus of claim 3 wherein the surface wave propagation mode is Goubau propagation.