Joint spectrum sensing scheme on the condition of coexistence of PU and SU signals

In cognitive radio communication, there is a real possibility of the primary user (PU) signal coexisting with that of secondary users (SUs) because of the hidden primary user problem, making it difficult to sense the PU signal when using existing spectrum sensing schemes. Therefore, based on known prior information regarding the SU signal, we propose a joint spectrum sensing (JSS) scheme to solve the problem of detecting the PU signal when it coexists with the SU signal. The JSS scheme preprocesses the received signal to remove the SU signal first, then detects the PU signal by the typical spectrum sensing scheme. The results of our theoretical analysis and simulation show that, compared with typical spectrum sensing schemes, the JSS scheme can detect the PU signal effectively in the presence of the SU signal and remove the influence of the SU signal on the JSS detection performance.