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Database-driven Dynamic Spectrum Sharing (DSS) is a promising technical paradigm for enhancing spectrum efficiency by allowing secondary user to opportunistically access licenced spectrum channels without interfering with primary users' transmissions. In database-driven DSS, a geo-location database administrator (DBA) maintains the spectrum availability in its service region in the form of a radio environment map (REM) and grant or deny secondary users' spectrum access requests based on primary users' activities. Crowdsourcing-based spectrum sensing has great potential in improving the accuracy of the REM at the DBA but requires strong incentives and privacy protection to simulate mobile users' participation. To tackle this challenge, this paper introduces a novel differentially-private reverse auction mechanism for crowdsourcing-based spectrum sensing. The proposed mechanism allows the DBA to select spectrum sensing participants under a budget constraint while offering differential bid privacy, approximate truthfulness, and approximate accuracy maximization. Extensive simulation studies using a real spectrum measurement dataset confirm the efficacy and efficiency of the proposed mechanism.
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Wideband Temporal Spectrum Sensing Using Cepstral Features
Spectrum sensing enables secondary users in a cognitive radio network to opportunistically access portions of the spectrum left idle by primary users. Tracking spectrum holes jointly in time and frequency over a wide spectrum band is a challenging task. In one approach to wideband temporal sensing, the spectrum band is partitioned into narrowband subchannels of fixed bandwidth, which are then characterized via hidden Markov modeling using average power or energy measurements as observation data. Adjacent, correlated subchannels are recursively aggregated into channels of variable bandwidths, corresponding to the primary user signals. Thus, wideband temporal sensing is transformed into a multiband sensing scenario by identifying the primary user channels in the spectrum band. However, future changes in the configuration of the primary user channels in the multiband setup cannot generally be detected using an energy detector front end for spectrum sensing. We propose the use of a cepstral feature vector to detect changes in the spectrum envelope of a primary user channel. Our numerical results show that the cepstrum-based spectrum envelope detector performs well under moderate to high signal-to-noise ratio conditions.
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- PAR ID:
- 10110319
- Date Published:
- Journal Name:
- 2019 IEEE 20th International Symposium on "A World of Wireless, Mobile and Multimedia Networks" (WoWMoM)
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Database-driven Dynamic Spectrum Sharing (DSS) is a promising technical paradigm for enhancing spectrum efficiency by allowing secondary user to opportunistically access licenced spectrum channels without interfering with primary users' transmissions. In database-driven DSS, a geo-location database administrator (DBA) maintains the spectrum availability in its service region in the form of a radio environment map (REM) and grant or deny secondary users' spectrum access requests based on primary users' activities. Crowdsourcing-based spectrum sensing has great potential in improving the accuracy of the REM at the DBA but requires strong incentives and privacy protection to simulate mobile users' participation. To tackle this challenge, this paper introduces a novel differentially-private reverse auction mechanism for crowdsourcing-based spectrum sensing. The proposed mechanism allows the DBA to select spectrum sensing participants under a budget constraint while offering differential bid privacy, approximate truthfulness, and approximate accuracy maximization. Extensive simulation studies using a real spectrum measurement dataset confirm the efficacy and efficiency of the proposed mechanism.more » « less
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In intelligent IoT networks, an IoT user is capable of sensing the spectrum and learning from its observation to dynamically access the wireless channels without interfering with the primary user’s signal. The network, however, is potentially subject to primary user emulation and jamming attacks. In the existing works, various attacks and defense mechanisms for spectrum sharing in IoT networks have been proposed. This paper systematically conducts a targeted survey of these efforts and proposes new approaches for future studies to strengthen the communication of IoT users. Our proposed methods involve the development of intelligent IoT devices that go beyond existing solutions, enabling them not only to share the spectrum with licensed users but also to effectively thwart potential attackers. First, considering practical aspects of imperfect spectrum sensing and delay, we propose to utilize online machine learning-based approaches to design spectrum sharing attack policies. We also investigate the attacker’s channel observation/sensing capabilities to design attack policies using time-varying feedback graph models. Second, taking into account the IoT devices’ practical characteristics of channel switching delay, we propose online learning-based channel access policies for optimal defense by the IoT device to guarantee the maximum network capacity. We then highlight future research directions, focusing on the defense of IoT devices against adaptive attackers. Finally, aided by concepts from intelligence and statistical factor analysis tools, we provide a workflow which can be utilized for devices’ intelligence factors impact analysis on the defense performance.more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/WoWMoM.2019.8793002
