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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Shades of White: Impacts of Population Dynamics and TV Viewership on Available TV Spectrum
Current regulations leave a few television (TV) white spaces in populated urban areas where spectrum shortage is mostly experienced. As TV set feedback becomes essential in the next generation terrestrial TV standard, an opportunistic TV spectrum sharing based on TV receiver activity information and transmit power control is proposed to exploit the underutilized active TV channels. Based on investigation of the spatial–spectral–temporal characteristics of TV receiver activities, analytical models are developed to capture the spatio-temporal distributions of available spectrum and corresponding capacity. The influence of multiple factors, such as feedback delay, spectrum handover overhead, ranking order, and distribution of TV channel popularity are discussed and modeled. The proposed power control mechanism is verified through experiments at representative campus and residential environments. Empirical data-based simulations and geographic analyses are conducted to evaluate the developed models and further profile the spectrum opportunities within a cell, across New York city (NYC) and other 273 cities in the United States. In NYC, the proposed solution provides a 3.8 – 11.7 -fold increase of average spectrum availability, and 2.5 – 6.6 -fold increase of capacity from current regulations. By investigating the feasibility and prospects of this approach, this paper intends to motivate further discussions in policy, business, and privacy aspects to reach its significant potential.
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- Award ID(s):
- 1731833
- PAR ID:
- 10088261
- Date Published:
- Journal Name:
- IEEE Transactions on Vehicular Technology
- Volume:
- 68
- Issue:
- 3
- ISSN:
- 0018-9545
- Page Range / eLocation ID:
- 2427 - 2442
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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