Systems, methods, and computer-readable media for a fair and efficient channel allocation and spectrum sensing for cognitive transmission in wireless networks are presented herein. A base station can send a cognitive user device a request to sense an idle channel associated with a primary network, and in response to receiving a willingness indicator or an attribute from the cognitive user device and/or a number of idle channels associated with the primary network sensed by the cognitive user device, the base station can assign the cognitive user device to transmit data on the idle channel associated with the primary network.