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As several new spectrum bands are opening up for shared use, a new paradigm of Diverse Band-aware Dynamic Spectrum Access (d-DSA) has emerged. d-DSA equips a secondary device with software defined radios (SDRs) and utilize whitespaces (or idle channels) in multiple bands, including but not limited to TV, LTE, Citizen Broadband Radio Service (CBRS), unlicensed ISM. In this paper, we propose a decentralized, online multi-agent reinforcement learning based cross-layer BAnd selection and Routing Design (BARD) for such d-DSA networks. BARD not only harnesses whitespaces in multiple spectrum bands, but also accounts for unique electro-magnetic characteristics of those bands to maximize the desired quality of service (QoS) requirements of heterogeneous message packets; while also ensuring no harmful interference to the primary users in the utilized band. Our extensive experiments demonstrate that BARD outperforms the baseline dDSAaR algorithm in terms of message delivery ratio, however, at a relatively higher network latency, for varying number of primary and secondary users. Furthermore, BARD greatly outperforms its single-band DSA variants in terms of both the metrics in all considered scenarios.
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Modeling Aggregate Interference with Heterogeneous Secondary Users and Passive Primary Users for Dynamic Admission and Power Control in TV Spectrum
Interference management in current TV white space and Citizens Broadband Radio Service networks is mainly based on geographical separation of primary and secondary users. This approach overprotects primary users at the cost of available spectrum for secondary users. Potential solutions include acquiring more primary user information, such as a measurement-enhanced geographical database, and cooperative primary user, such as the TV set feedback in the next generation TV systems. However, one challenge of these solutions is to effectively manage the aggregate interference at TV receivers from interweaving secondary users. In this paper, a stochastic geometry-based aggregate interference model is developed for unlicensed spectrum shared by heterogeneous secondary users that have various transmit powers and multi-antenna capabilities. Moreover, an efficient computation approach is presented to capture network dynamics in real-time via a down-sampling that preserves high-quantile precision of the model. The stochastic geometry-based model is verified experimentally in ISM band. It is shown that the model enables separate control of admission and transmit power of multiple co-located secondary networks to protect primary users and maximize spectrum utilization.
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- Award ID(s):
- 1731833
- PAR ID:
- 10075909
- Date Published:
- Journal Name:
- International Balkan Conference on Communications and Networking
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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- The DOI is not currently available.
