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 sensing; defining a cost formula for calculating a cost associated with using sensors from the candidate set in the cooperative spectrum sensing; and partitioning the candidate set into a an active set containing any sensor(s) of the candidate set to participate in the cooperative spectrum sensing and a passive set containing any sensor(s) of the candidate set not to participate in the cooperative spectrum sensing by applying an optimization procedure which performs a constrained optimization of the cost in accordance with the defined cost formula.