Optimal Sensing Cardinality for Cognitive Radios

This letter puts forth a proactive approach for determining the sensing cardinality (the number of subchannels to sense) in a multiband cognitive radio network with limited available block energy. Specifically, we present the sensing cardinality that maximizes the achievable block rate of the cognitive user by optimally allocating available energy to the wideband spectrum sensing and data transmission. We further derive the closed-form expression for this optimal sensing cardinality when each subchannel has the identical primary spectrum occupancy statistics.