Cognitive radio networks, a.k.a. dynamic spectrum access networks, offer a promising solution to the problems of spectrum scarcity and under-utilization. In this paper, we consider two single-user links: primary and secondary links. To increase secondary user (SU) transmission opportunities and increase primary user (PU) throughput, we consider a cognitive relay network where a SU relays PU packets that are unsuccessfully received at the primary receiver (PR). At the PR side, two protocols are suggested: i) energy accumulation (EA), and ii) mutual-information accumulation (MIA). The average stable throughput of the secondary link is derived under these protocols for a specific throughput selected by the primary link. Results show that EA and MIA can significantly improve the secondary throughput compared with the no accumulation scenario, especially under extreme environment.
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Mitigation of the spectrum sensing data falsifying attack in cognitive radio networks
Cognitive radio networks (CRNs), which offer novel network architecture for utilising spectrums, have attracted significant attention in recent years. CRN users use spectrums opportunistically, which means they sense a channel, and if it is free, they start transmitting in that channel. In cooperative spectrum sensing, a secondary user (SU) decides about the presence of the primary user (PU) based on information from other SUs. Malicious SUs (MSUs) send false sensing information to other SUs so that they make wrong decisions about the spectrum status. As a result, an SU may transmit during the presence of the PU or may keep starving for the spectrum. In this paper, we propose a reputation-based mechanism which can minimise the effects of MSUs on decision making in cooperative spectrum sensing. Some of the SUs are selected as distributed fusion centres (DFCs), that are responsible for making decisions about the presence of PU and informing the reporting SUs. A DFC uses weighted majority voting among the reporting SUs, where weights are normalised reputation. The DFC updates reputations of SUs based on confidence of an election. If the majority wins by a significant margin, the confidence of the election is high. In this case, SUs that belong to the majority gain high reputations. We conduct extensive simulations to validate our proposed model.
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- PAR ID:
- 10196972
- Date Published:
- Journal Name:
- Cyber-Physical Systems
- ISSN:
- 2333-5777
- Page Range / eLocation ID:
- 1 to 20
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1080/23335777.2020.1811387
