Below is a nice illustration on Radio Spectrum Allocations (Yankee Group):

Radio Spectrum Allocations

…and those with the spectrum, the spectrum-rich players, are in the driver’s seat for Mobile Broadband economics.

Radio spectrum is a scarce resource that is critical for mobile communications. The expansion of mobile broadband services places tremendous pressure on available spectrum resources, and typically sees service providers with greater spectrum bandwidth having a distinct economic advantage as broadband services take hold. The most coveted spectrum bands are those that support mobile communications (generally less than 3 GHz operating frequency), have adequate bandwidth for economic service delivery and are aligned with a robust device and infrastructure ecosystem. These key resources include six distinct frequency bands that are illustrated above.

(Source: Yankee Group, June 2009)