US 11,784,416 B2
Tunable radio frequency (RF) absorber and thermal heat spreader
Jeremy J. Holdstock, McKinney, TX (US); James E. Foreman, Frisco, TX (US); David R. Gorman, Lucas, TX (US); and Darrell W. Miller, Allen, TX (US)
Assigned to Raytheon Company, Waltham, MA (US)
Filed by Raytheon Company, Waltham, MA (US)
Filed on Jan. 6, 2020, as Appl. No. 16/735,497.
Prior Publication US 2021/0210862 A1, Jul. 8, 2021
Int. Cl. H01Q 17/00 (2006.01); H05K 9/00 (2006.01)
CPC H01Q 17/008 (2013.01) [H05K 9/0088 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus comprising:
a first layer comprising a radio frequency (RF) lossy material mounted to a platform;
a second layer comprising the RF lossy material;
a plurality of conductive or resistive pads arranged in a planar array between the first layer and the second layer, the pads separated from each other by gaps, wherein dimensions of each pad and each gap are selected based on a desired resonant frequency band of RF energy transmitted by at least one RF source associated with the platform; and
a plurality of thermal vias, each thermal via corresponding to one of the pads and extending through at least the first layer, each thermal via formed of a thermally-conductive material;
wherein each thermal via has a first dimension across the thermal via that is at least one-third as large as a second dimension across the corresponding pad, the first dimension and the second dimension being measured in a same plane.