Attack-tolerant distributed sensing for dynamic spectrum access networks

Accurate sensing of the spectrum condition is of crucial importance to the mitigation of the spectrum scarcity problem in dynamic spectrum access (DSA) networks. Specifically, distributed sensing has been recognized as a viable means to enhance the incumbent signal detection by exploiting the diversity of sensors. However, it is challenging to make such distributed sensing secure due mainly to the unique features of DSA networks - openness of a low-layer protocol stack in SDR devices and non-existence of communications between primary and secondary devices. To address this challenge, we propose attack-tolerant distributed sensing protocol (ADSP), under which sensors in close proximity are grouped into a cluster, and sensors in a cluster cooperatively safeguard distributed sensing. The heart of ADSP is a novel shadow fading correlation-based filter tailored to anomaly detection, by which the fusion center prefilters abnormal sensor reports via cross-validation. By realizing this correlation filter, ADSP minimizes the impact of an attack on the performance of distributed sensing, while incurring minimal processing and communications overheads. The efficacy of our scheme is validated on a realistic two-dimensional shadow-fading field, which accurately approximates real-world shadowing environments. Our extensive simulation-based evaluation shows that ADSP significantly reduces the impact of attacks on incumbent detection performance.