Cooperative spectrum sensing in cognitive radio networks with regenerative relay of signals in the delivery channel

The spectrum sensing at the frequencies of «white spaces» is an important feature for cognitive radio networks. The characteristics of detection of licensed primary users by single secondary users will deteriorate under the influence of fading in the radio channels, both in the sensing channels and in the reporting channels of results. Reliable detection of licensed primary users is implemented on the basis of the secondary users cooperative spectrum sensing. The article considers the possibility of constructing the reporting channel based on the scheme of regenerative relaying of «hard» single-bit local solutions in the form of binary phase-shift keying of signals from remote secondary users to a Central Station, which forms a global decision about the result of sensing. The potential value of the gain of the scheme with relay in relation to the scheme with direct transmission and the conditions for optimal placement of the repeater in channels with Rayleigh fades are determined.