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To address the scarcity of spectrum, FCC mandated the dynamic sharing of spectrum among the different tiers of users. The success of spectrum sharing, however, relies on the automated enforcement of spectrum policies. We focus on ex post spectrum enforcement during/after the occurrence of a potentially harmful event, but before/after an actual harm has occurred. The major challenges addressed by us are to ensure maximum channel coverage in a given region of enforcement, accurate and reliable detection of enforcement, and selection of an efficient algorithm to select entities for detection of violation. We adopt a crowdsourced methodology to monitor spectrum usage. We ensure maximum coverage of the given area by dividing it into equal-sized regions and solve the enforcement problem by a divide and conquer mechanism over the entire region. We use a variant of the Multiple Choice Secretary algorithm to select volunteers. We finally simulate the enforcement framework and analyze the results.
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Spectrum Misuse Detection in Cooperative Wireless Networks
The success of dynamic spectrum sharing in wireless networks depends on reliable automated enforcement of spectrum access policies. In this paper, a crowdsourced approach is used to select volunteers to detect spectrum misuse. Volunteer selection is based on multiple criteria, including their reputation, likelihood of being in a region and ability to effectively detect channel misuse. We formulate the volunteer selection problem as a stable matching problem, whereby, volunteers' monitoring preferences are matched to channels' attributes. Given a set of volunteers, the objective is to ensure maximum coverage of the spectrum enforcement area and accurate detection of spectrum access violation of all channels in the area. The two matching algorithms, Volunteer Matching (VM) and Reverse Volunteer Matching (RVM) are based on variants of the Gale-Shapley algorithm for stable matching. We also propose two Hybrid algorithms, HYBRID-VM and HYBRID-RVM that augment the matching algorithms with a Secretary-based algorithm to overcome the shortcomings of the individual vanilla algorithms. Simulation results show that volunteer selection by using HYBRID-VM gives better coverage of region (better by 19.2% when compared to threshold-based Secretary algorithm), better accuracy of detection and better volunteer happiness when compared to the other algorithms that are tested.
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- Award ID(s):
- 1642949
- PAR ID:
- 10218691
- Date Published:
- Journal Name:
- GLOBECOM 2020 - 2020 IEEE Global Communications Conference
- Page Range / eLocation ID:
- 1 to 6
- 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
- Conference Paper:
- https://doi.org/10.1109/CCNC46108.2020.9045655
