Communication technologies are evolving drastically in recent years. However, the scarcity of spectrum began to appear with the accelerating usage of various communication technologies, as well as the preservation of traditional channel access methods. Cognitive Radio (CR) is an innovative solution for the spectrum scarcity. Spectrum sensing (SS) is a key task of CR life-cycle that gains significance as spectrum holes can be detected during this task. This paper studies and compares the performance of the KMeans-based SS technique with the non-cooperative technique (Non-CSS), the And-based, and the Orbased techniques in stationary and mobile CR networks (CRNs). We consider different fading channels. The results reveal that SS techniques provide better performance in stationary networks as compared to mobile networks. Further, our experimental results show that at least three SUs and about 1500 samples are needed to reach an acceptable performance. In addition, the results show that the KMeans-based technique slightly outperforms the Or-based technique, especially in highly noisy environments and under severe fading channels.