In distributed cognitive radio networks (CRNs)

a common fusion centre is always not available to collect the sensing results from all cooperative users

and the sensing cooperation is likely to be disrupted by spectrum sensing data falsification (SSDF) attacks.Allowing for these factors

this paper proposes a modified consensus-based scheme for decentralized cooperative spectrum sensing(CSS).Utilizing the iteration rule based on Metropolis weight matrix

each secondary user (SU) can maintain cooperation with others only through the local information exchange in the neighborhood

without requiring any a priori knowledge of the whole network.To counter three potential attack models of SSDF

some anti-attack strategies are also introduced

by which the authentic SUs can identify and reject the malicious users quickly.As represented by the extensive simulation results

the proposed scheme can generally guarantee most authentic SUs to reach a consensus and make right decisions individually; also

it is proved to be much more robust against all potential SSDF attacks

compared with the existing consensus-based scheme.