Non-Cooperative Blind Spectrum Sensing for Primary Users in Cognitive Radio Networks with DS-CDMA

Real-time spectrum sensing with precise accuracy is the most important step to establish the cognitive radio networks (CRNs). Detecting the presence of the great primary users (PUs) who use DS-CDMA (Direct sequence code division multiple access) technique is a challenge for the secondary users (SUs) in CRNs. DS-CDMA transmissions with very low signal to the noise ratio (SNR) results in a signal hidden below the noise level, therefore, the existing classic detection methods are not effective enough to sense the signals. In this paper, a method is proposed to meet this challenge. The proposed method based on the fluctuations of the correlation estimators searches on a specific frequency band and detects the primary userʹs signals. Simulation results show that the sensing performance of the method is better than the other conventional schemes for dealing with the DS-CDMA users.