Patent ID: 8270906
Filing Date: 2012-09-18
Classification: H04W

Abstract:
1. A method relating to cooperative spectrum sensing, the method comprising: obtaining a candidate set of sensors that are available to participate in the cooperative spectrum and for each sensor in the candidate set its radial distance to a central coordinating node in a communication system; initiating a next minimum radius to zero; setting a number of sensors that can be accommodated at the initiated next minimum radius equal to one; selecting the central coordinating node to an active set of sensors to participate in the cooperative spectrum sensing; a) calculating a new next minimum radius such that an estimated probability of a sensor at the new next minimum radius from the central coordinating node being correlated with any sensor that could be accommodated at the previous next minimum radius is equal to a second design probability threshold; b) checking whether or not the new next minimum radius meets one or more predetermined constraints and, if not, recalculating the new next minimum radius such that it meets the one or more constraints; c) determining a number of sensors that can be accommodated at the new next minimum radius, said number of sensors being the greatest integer such that a probability that such an integer number of sensors at the new next minimum radius do not experience any mutual shadowing correlation is greater than or equal to a first design probability threshold; d) if the candidate set includes a number, equal to or greater than the determined number of sensors that can be accommodated at the new next minimum radius, of sensors which all have radial distances to the central coordinating node that exceed the new next minimum radius, selecting to the active set a number, equal to the determined number of sensors that can be accommodated at the new next minimum radius, of sensors which have the smallest radial distances to the central coordinating node that still exceed the new next minimum radius; e) if the candidate set does not include a number, equal to or greater than the determined number of sensors that can be accommodated at the new next minimum radius, of sensors which all have radial distances to the central coordinating node that exceed the new next minimum radius, selecting to the active set every, if any, sensor in the candidate set which has a radial distance to the central coordinating node greater than the new next minimum radius and terminating the selection of sensors to the active set; and f) if the selection of sensors to the active set has not terminated, repeating the steps a) to f).