摘要 |
A device and method for selecting a frequency channel of given bandwidth in a cognitive radio application is disclosed. In one aspect, the method includes evaluating, at one of a plurality of frequency bins, a function indicative of the frequency occupancy. If the evaluation result indicates free spectrum at the considered frequency bin, the previous step is repeated for a frequency bin adjacent to the considered frequency bin until the free frequency bins constitute a frequency channel of the given bandwidth. Otherwise, the method moves to select a next frequency bin to be considered. It is selected by calculating a measure of the left and right derivative of the function at the considered frequency bin, taking the measure of the left or right derivative as gradient approximation, and determining the next frequency bin by shifting the considered frequency bin over a frequency shift inversely proportional to the gradient approximation.
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