Spectrum sensing for the unlicensed band cognitive radio

If several different systems operate in the same frequency band, in order to effectively use the available spectrum there has to be some coordination between them. The coordination is especially important if the systems are not designed to operate in such an environment. The initial and a very important part of the coordination process is the acquiring of the spectrum usage map or spectrum sensing. The paper describes the spectrum sensing experimentation in the unlicensed 2.4 GHz band during the WiFi transmission. It shows the experiment flow and the obtained results. The experiments were performed at NITOS testbed at the University of Thessaly, Greece.