07521890 is referenced by 194 patents and cites 4 patents.

A system and method is provided for the inductive transfer of electric power between a substantially flat primary surface and a multitude of secondary devices in such a way that the power transfer is localized to the vicinities of individual device coils. The contact free power transfer does not require precise physical alignment between the primary surface and the secondary device and can allow the secondary device or devices to be placed anywhere and in arbitrary orientation with respect to the primary surface. Such power transfer is realized without the need of complex high frequency power switching network to turn the individual primary coils on or off and is completely scalable to almost arbitrary size. The local anti-resonance architecture of the primary device will block primary current from flowing when no secondary device or devices are in proximity to the local RF power network. The presence of a tuned secondary device detunes the local anti-resonance on the primary surface; thereby enable the RF power to be transferred from the local primary coils to the secondary device. The uniformity of the inductive coupling between the active primary surface and the secondary devices is improved with a novel multi-pole driving technique which produces an apparent traveling wave pattern across the primary surface.

Title
System and method for selective transfer of radio frequency power
Application Number
11/319818
Publication Number
7521890 (B2)
Application Date
December 27, 2005
Publication Date
April 21, 2009
Inventor
Victor Su
Mountain View
CA, US
Yeechun Lee
Mountain View
CA, US
Agent
John P Moran
Holland & Knight
Assignee
Power Science
CA, US
IPC
H01M 10/46
View Original Source