Cognitive radio is being intensively researched as the enabling technology for license-exempt access to the so-called TV White Spaces (TVWS). large portions of spectrum in the UHF/VHF bands which become available on a geographical basis after digital switchover. Both in the US. and more recently. https://www.ngetikin.com/super-value-1-2-in-Tobacco-Road-Acacia-Distressed-Engineered-Hardwood-Flooring-4-8-in-Wide-Sample-quick-super/