A method for spectrum sensing for cognitive radio includes performing a process of local spectrum sensing using receive beamforming and energy detection at each of a plurality of secondary users included in a cognitive radio network, wherein the process of local spectrum sensing decides between two hypotheses corresponding to absence and presence of a primary user, the two hypotheses being formulated using a primary user signal, a plurality of co-channel interferences, and sensing noise, the primary user signal, the plurality of co-channel interferences, and the sensing noise being received at each of the plurality of secondary users, and a set of beamforming weights of the receive beamforming is determined by optimizing a probability of detection and constraining a probability of false alarm.