Patent ID: 8023574

Claim:
An apparatus comprising: a discrete Fourier transform (DFT) engine to perform a DFT on orthogonal frequency division multiplexing (OFDM) symbols received from a communication medium, said DFT engine having a variable DFT size; a controller to: (a) vary a number of subcarriers (N) being used by said apparatus to communicate with other devices, based on a predetermined criterion, (b) cause said DFT size of said DFT engine to change in accordance with said number of subcarriers, (c) check a data file for bandwidth availability within the network cell each time an increase in the number of subcarriers is to be made, wherein the data file indicates portions of an electromagnetic spectrum for which Federal Communications Commission (FCC) licenses are currently obtained for a network cell, and (d) determine whether a FCC license has been acquired to use spectrum associated with said increased number of subcarriers using the data file, when the FCC license is required.