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Kang G Shin - One of the best experts on this subject based on the ideXlab platform.

  • Wi-Fi 2.0: Price and quality competitions of duopoly cognitive radio wireless service providers with time-varying Spectrum Availability
    2011 Proceedings IEEE INFOCOM, 2011
    Co-Authors: Jaehyuk Choi, Kang G Shin
    Abstract:

    The whitespaces (WS) in the legacy Spectrum provide new opportunities for the future Wi-Fi-like Internet access, often called Wi-Fi 2.0, since service quality can be greatly enhanced thanks to the better propagation characteristics of the WS than the ISM bands. In the Wi-Fi 2.0 networks, each wireless service provider (WSP) temporarily leases a licensed Spectrum band from the licensees and opportunistically utilizes it during the absence of the legacy users. The WSPs in Wi-Fi 2.0 thus face unique challenges since Spectrum Availability of the leased channel is time-varying due to the ON/OFF Spectrum usage patterns of the legacy users, which necessitates the eviction control of in-service customers at the return of legacy users. As a result, to maximize its profit, a WSP should consider both channel leasing and eviction costs to optimally determine a Spectrum band to lease and a service tariff. In this paper, we consider a duopoly Wi-Fi 2.0 market where two co-located WSPs compete for the Spectrum and customers. The competition between the WSPs is analyzed using game theory to derive the Nash Equilibria (NE) of the price (of the service tariffs) and the quality (of the leased channel, in terms of channel utilization) competitions. The NE existence condition and market entry barriers are also derived. Via an extensive numerical analysis, we show the tradeoffs between leasing/eviction cost, customer arrivals, and channel usage patterns by the legacy users.

  • INFOCOM - Wi-Fi 2.0: Price and quality competitions of duopoly cognitive radio wireless service providers with time-varying Spectrum Availability
    2011 Proceedings IEEE INFOCOM, 2011
    Co-Authors: Jaehyuk Choi, Kang G Shin
    Abstract:

    The whitespaces (WS) in the legacy Spectrum provide new opportunities for the future Wi-Fi-like Internet access, often called Wi-Fi 2.0, since service quality can be greatly enhanced thanks to the better propagation characteristics of the WS than the ISM bands. In the Wi-Fi 2.0 networks, each wireless service provider (WSP) temporarily leases a licensed Spectrum band from the licensees and opportunistically utilizes it during the absence of the legacy users. The WSPs in Wi-Fi 2.0 thus face unique challenges since Spectrum Availability of the leased channel is time-varying due to the ON/OFF Spectrum usage patterns of the legacy users, which necessitates the eviction control of in-service customers at the return of legacy users. As a result, to maximize its profit, a WSP should consider both channel leasing and eviction costs to optimally determine a Spectrum band to lease and a service tariff. In this paper, we consider a duopoly Wi-Fi 2.0 market where two co-located WSPs compete for the Spectrum and customers. The competition between the WSPs is analyzed using game theory to derive the Nash Equilibria (NE) of the price (of the service tariffs) and the quality (of the leased channel, in terms of channel utilization) competitions. The NE existence condition and market entry barriers are also derived. Via an extensive numerical analysis, we show the tradeoffs between leasing/eviction cost, customer arrivals, and channel usage patterns by the legacy users.

Jaehyuk Choi - One of the best experts on this subject based on the ideXlab platform.

  • Wi-Fi 2.0: Price and quality competitions of duopoly cognitive radio wireless service providers with time-varying Spectrum Availability
    2011 Proceedings IEEE INFOCOM, 2011
    Co-Authors: Jaehyuk Choi, Kang G Shin
    Abstract:

    The whitespaces (WS) in the legacy Spectrum provide new opportunities for the future Wi-Fi-like Internet access, often called Wi-Fi 2.0, since service quality can be greatly enhanced thanks to the better propagation characteristics of the WS than the ISM bands. In the Wi-Fi 2.0 networks, each wireless service provider (WSP) temporarily leases a licensed Spectrum band from the licensees and opportunistically utilizes it during the absence of the legacy users. The WSPs in Wi-Fi 2.0 thus face unique challenges since Spectrum Availability of the leased channel is time-varying due to the ON/OFF Spectrum usage patterns of the legacy users, which necessitates the eviction control of in-service customers at the return of legacy users. As a result, to maximize its profit, a WSP should consider both channel leasing and eviction costs to optimally determine a Spectrum band to lease and a service tariff. In this paper, we consider a duopoly Wi-Fi 2.0 market where two co-located WSPs compete for the Spectrum and customers. The competition between the WSPs is analyzed using game theory to derive the Nash Equilibria (NE) of the price (of the service tariffs) and the quality (of the leased channel, in terms of channel utilization) competitions. The NE existence condition and market entry barriers are also derived. Via an extensive numerical analysis, we show the tradeoffs between leasing/eviction cost, customer arrivals, and channel usage patterns by the legacy users.

  • INFOCOM - Wi-Fi 2.0: Price and quality competitions of duopoly cognitive radio wireless service providers with time-varying Spectrum Availability
    2011 Proceedings IEEE INFOCOM, 2011
    Co-Authors: Jaehyuk Choi, Kang G Shin
    Abstract:

    The whitespaces (WS) in the legacy Spectrum provide new opportunities for the future Wi-Fi-like Internet access, often called Wi-Fi 2.0, since service quality can be greatly enhanced thanks to the better propagation characteristics of the WS than the ISM bands. In the Wi-Fi 2.0 networks, each wireless service provider (WSP) temporarily leases a licensed Spectrum band from the licensees and opportunistically utilizes it during the absence of the legacy users. The WSPs in Wi-Fi 2.0 thus face unique challenges since Spectrum Availability of the leased channel is time-varying due to the ON/OFF Spectrum usage patterns of the legacy users, which necessitates the eviction control of in-service customers at the return of legacy users. As a result, to maximize its profit, a WSP should consider both channel leasing and eviction costs to optimally determine a Spectrum band to lease and a service tariff. In this paper, we consider a duopoly Wi-Fi 2.0 market where two co-located WSPs compete for the Spectrum and customers. The competition between the WSPs is analyzed using game theory to derive the Nash Equilibria (NE) of the price (of the service tariffs) and the quality (of the leased channel, in terms of channel utilization) competitions. The NE existence condition and market entry barriers are also derived. Via an extensive numerical analysis, we show the tradeoffs between leasing/eviction cost, customer arrivals, and channel usage patterns by the legacy users.

Qiu Wang - One of the best experts on this subject based on the ideXlab platform.

  • WUWNet - Connectivity of underwater cognitive acoustic networks under Spectrum constraint
    Proceedings of the Thirteenth ACM International Conference on Underwater Networks & Systems, 2018
    Co-Authors: Qiu Wang, Hong-ning Dai, Hao Wang, Qubeijian Wang
    Abstract:

    There is an extensive attention on underwater cognitive acoustic networks (UCANs) since acoustic Spectrum becomes deficient owning to the proliferation of human activity in ocean. This paper presents an overview of our recent progress in investigating the connectivity of secondary users (SUs) in UCANs. In particular, this model takes both topological connectivity and Spectrum Availability into account. Simulation results verify the accuracy of the proposed model.

  • Connectivity of Underlay Cognitive Radio Networks With Directional Antennas
    IEEE Transactions on Vehicular Technology, 2018
    Co-Authors: Qiu Wang, Orestis Georgiou, Wei Zhang
    Abstract:

    In underlay cognitive radio networks (CRNs), the connectivity of secondary users (SUs) is difficult to be guaranteed due to the existence of primary users. Most prior studies only consider cognitive radio networks equipped with omni-directional antennas causing high interference at SUs. We name such CRNs with omni-directional antennas as Omn-CRNs. Compared with an omni-directional antenna, a directional antenna can concentrate the transmitting/receiving capability at a certain direction, consequently resulting in the less interference. In this paper, we investigate the connectivity of SUs in CRNs with directional antennas (named as Dir-CRNs). In particular, we derive closed-form expressions of the connectivity of SUs of both Dir-CRNs and Omn-CRNs, thus enabling tractability. We show that the connectivity of SUs is mainly affected by two constraints: the Spectrum Availability of SUs and the topological connectivity of SUs. Extensive simulations validate the accuracy of our proposed models. Meanwhile, we also show that Dir-CRNs can have higher connectivity than Omn-CRNs mainly due to the lower interference, the higher Spectrum Availability, and the higher topological connectivity brought by directional antennas. Moreover, we also extend our analysis with considering transmission power efficiency. The simulation results show that Dir-CRNs require less transmission power to establish links than Omn-CRNs. We further investigate the throughput capacity of SUs, which is shown to heavily depend on the connectivity of SUs.

  • Connectivity of Underlay Cognitive Radio Networks with Directional Antennas
    IEEE Transactions on Vehicular Technology, 2018
    Co-Authors: Qiu Wang, Orestis Georgiou, Hong-ning Dai, Zhiguo Shi, Wei Zhang
    Abstract:

    In cognitive radio networks (CRNs), the connectivity of secondary users (SUs) is difficult to be guaranteed due to the existence of primary users (PUs). Most prior studies only consider cognitive radio networks equipped with omni-directional antennas causing high interference at SUs. We name such CRNs with omni-directional antennas as Omn-CRNs. Compared with an omni-directional antenna, a directional antenna can concentrate the transmitting/receiving capability at a certain direction, consequently resulting in less interference. In this paper, we investigate the connectivity of SUs in CRNs with directional antennas (named as Dir-CRNs). In particular, we derive closed-form expressions of the connectivity of SUs of both Dir-CRNs and Omn-CRNs, thus enabling tractability. We show that the connectivity of SUs is mainly affected by two constraints: the Spectrum Availability of SUs and the topological connectivity of SUs. Extensive simulations validate the accuracy of our proposed models. Meanwhile, we also show that Dir-CRNs can have higher connectivity than Omn-CRNs mainly due to the lower interference, the higher Spectrum Availability and the higher topological connectivity brought by directional antennas.

  • Link Connectivity and Coverage of Underwater Cognitive Acoustic Networks under Spectrum Constraint.
    Sensors (Basel Switzerland), 2017
    Co-Authors: Qiu Wang, Hong-ning Dai, Chak Fong Cheang, Hao Wang
    Abstract:

    Extensive attention has been given to the use of cognitive radio technology in underwater acoustic networks since the acoustic Spectrum became scarce due to the proliferation of human aquatic activities. Most of the recent studies on underwater cognitive acoustic networks (UCANs) mainly focus on Spectrum management or protocol design. Few efforts have addressed the quality-of-service (QoS) of UCANs. In UCANs, secondary users (SUs) have lower priority to use acoustic Spectrum than primary users (PUs) with higher priority to access Spectrum. As a result, the QoS of SUs is difficult to ensure in UCANs. This paper proposes an analytical model to investigate the link connectivity and the probability of coverage of SUs in UCANs. In particular, this model takes both topological connectivity and Spectrum Availability into account, though Spectrum Availability has been ignored in most recent studies. We conduct extensive simulations to evaluate the effectiveness and the accuracy of our proposed model. Simulation results show that our proposed model is quite accurate. Besides, our results also imply that the link connectivity and the probability of coverage of SUs heavily depend on both the underwater acoustic channel conditions and the activities of PUs.

Wei Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Connectivity of Underlay Cognitive Radio Networks With Directional Antennas
    IEEE Transactions on Vehicular Technology, 2018
    Co-Authors: Qiu Wang, Orestis Georgiou, Wei Zhang
    Abstract:

    In underlay cognitive radio networks (CRNs), the connectivity of secondary users (SUs) is difficult to be guaranteed due to the existence of primary users. Most prior studies only consider cognitive radio networks equipped with omni-directional antennas causing high interference at SUs. We name such CRNs with omni-directional antennas as Omn-CRNs. Compared with an omni-directional antenna, a directional antenna can concentrate the transmitting/receiving capability at a certain direction, consequently resulting in the less interference. In this paper, we investigate the connectivity of SUs in CRNs with directional antennas (named as Dir-CRNs). In particular, we derive closed-form expressions of the connectivity of SUs of both Dir-CRNs and Omn-CRNs, thus enabling tractability. We show that the connectivity of SUs is mainly affected by two constraints: the Spectrum Availability of SUs and the topological connectivity of SUs. Extensive simulations validate the accuracy of our proposed models. Meanwhile, we also show that Dir-CRNs can have higher connectivity than Omn-CRNs mainly due to the lower interference, the higher Spectrum Availability, and the higher topological connectivity brought by directional antennas. Moreover, we also extend our analysis with considering transmission power efficiency. The simulation results show that Dir-CRNs require less transmission power to establish links than Omn-CRNs. We further investigate the throughput capacity of SUs, which is shown to heavily depend on the connectivity of SUs.

  • Connectivity of Underlay Cognitive Radio Networks with Directional Antennas
    IEEE Transactions on Vehicular Technology, 2018
    Co-Authors: Qiu Wang, Orestis Georgiou, Hong-ning Dai, Zhiguo Shi, Wei Zhang
    Abstract:

    In cognitive radio networks (CRNs), the connectivity of secondary users (SUs) is difficult to be guaranteed due to the existence of primary users (PUs). Most prior studies only consider cognitive radio networks equipped with omni-directional antennas causing high interference at SUs. We name such CRNs with omni-directional antennas as Omn-CRNs. Compared with an omni-directional antenna, a directional antenna can concentrate the transmitting/receiving capability at a certain direction, consequently resulting in less interference. In this paper, we investigate the connectivity of SUs in CRNs with directional antennas (named as Dir-CRNs). In particular, we derive closed-form expressions of the connectivity of SUs of both Dir-CRNs and Omn-CRNs, thus enabling tractability. We show that the connectivity of SUs is mainly affected by two constraints: the Spectrum Availability of SUs and the topological connectivity of SUs. Extensive simulations validate the accuracy of our proposed models. Meanwhile, we also show that Dir-CRNs can have higher connectivity than Omn-CRNs mainly due to the lower interference, the higher Spectrum Availability and the higher topological connectivity brought by directional antennas.

Miia Mustonen - One of the best experts on this subject based on the ideXlab platform.

  • live field trial of licensed shared access lsa concept using lte network in 2 3 ghz band
    IEEE International Symposium on Dynamic Spectrum Access Networks, 2014
    Co-Authors: Marko Palola, Miia Mustonen, Marja Matinmikko, Jarmo Prokkola, Marjo Heikkila, Tero Kippola, Seppo Yrjola, Vesa Hartikainen, Lucia Tudose, Arto Kivinen
    Abstract:

    This paper presents the results from a live field trial of the new Licensed Shared Access (LSA) concept using a TD-LTE network in the 2.3 GHz Spectrum band in Finland. In the trial a live LTE network shares the Spectrum from incumbent programme making and special events (PMSE) service including cordless cameras without causing harmful interference. The trial implements the new LSA concept and the required new building blocks including LSA Repository for Spectrum Availability information and LSA Controller for commanding the mobile communication network in the band. The trial uses a real TD-LTE base station, real network management system, and real core network. Incumbent Spectrum usage data is collected to the LSA Repository and used by the LSA Controller to retrieve available Spectrum bands. LSA Controller uses the network management system to configure the base station according to the Spectrum Availability information. Incumbent Spectrum users' rights are protected by evacuating the LSA band and handing users over from the LTE network to other networks when requested by the incumbent Spectrum user. Numerical results are presented to quantify the duration of the LSA band evacuation process. The demonstration shows that the new LSA concept can be implemented with existing network elements and a minimum amount of new components. The first performance results on the LSA band evacuation times indicate that the LSA band can be evacuated and released in good time and the incumbents' rights can be protected.

  • Fuzzy-Logic Based Framework for Spectrum Availability Assessment in Cognitive Radio Systems
    IEEE Journal on Selected Areas in Communications, 2013
    Co-Authors: Marja Matinmikko, Tapio Rauma, Javier Del Ser, Miia Mustonen
    Abstract:

    This paper presents a novel decision-making system for the selection of methods to obtain knowledge of Spectrum Availability in future mobile communication systems equipped with cognitive radio system (CRS) capabilities. The proposed decision-making scheme selects the methods to obtain knowledge of Spectrum Availability between control channels, databases and Spectrum sensing based on the specific requirements of the frequency band at hand. The developed decision-making system considers realistic frequency bands and Spectrum sharing scenarios, including bands with primary allocation to mobile service where the operator governs the Spectrum use, bands with co-primary or secondary allocation to mobile service where the primary users have to be protected from harmful interference, and finally license-exempt bands, where different systems coexist in uncontrolled interference conditions. Specifically, a novel rule-based decision-making system with a learning mechanism is developed to select among different Spectrum sensing techniques including matched filtering, correlation detection, feature detection, energy detection, and cooperative sensing. The decision making system is further applied to operator-governed opportunistic networks, which are dynamically created temporary extensions of the mobile infrastructure networks. Performance evaluation is done by assuming changing operational conditions so as to elucidate the gains of the proposed decision making system with respect to the case when the sensing approach is kept fixed.

  • decision making system for obtaining Spectrum Availability information in opportunistic networks
    Cognitive Radio and Advanced Spectrum Management, 2011
    Co-Authors: Marja Matinmikko, Tapio Rauma, Miia Mustonen, Javier Del Ser
    Abstract:

    Opportunistic networks with cognitive management systems can improve the resource use in future wireless communication networks by forming local clusters that are temporary extensions of the infrastructure and governed by the operator. This paper presents a decision making system that selects the techniques for obtaining Spectrum Availability information in opportunistic networks. The proposed decision making system selects the most suitable technique(s) from cognitive control channels, databases, and Spectrum sensing techniques. Moreover, a novel and simple rule-based expert system is developed to choose the Spectrum sensing technique among energy detection, correlation-based detection, and waveform-based detection. The selection is made based on the required probability of detection, operational SNR, available time, and available a priori information. The developed rule-based decision making system is presented in the form of a decision tree to illustrate the dominating paths that influence the decisions. Situations where none of the considered Spectrum sensing techniques can meet the given conditions are identified and new approaches are proposed including cooperative sensing and changing of the channel. Results are presented to verify the functioning of the proposed decision making system and to show the relative frequencies of the different selected sensing techniques. Significant improvements can be obtained when the decision making system is used compared to using a single sensing technique instead.

  • architecture and approach for obtaining Spectrum Availability information
    Vehicular Technology Conference, 2011
    Co-Authors: Marja Matinmikko, Tapio Rauma, Miia Mustonen, Javier Del Ser
    Abstract:

    This paper presents a novel architecture and approach for obtaining Spectrum Availability information in future cognitive radio systems (CRS). CRS can opportunistically access Spectrum by identifying unoccupied channels while keeping higher priority systems on the same channel free from harmful interference. Knowledge of the current state of the Spectrum use is of utmost importance for CRS operations. There are different techniques for obtaining Spectrum Availability information including e.g. cognitive pilot channels, databases, Spectrum sensing techniques, and combinations thereof. For Spectrum sensing there are different algorithms and cooperative combining techniques with different characteristics and capabilities in terms of e.g. performance, complexity, and requirement of a priori information. This paper presents a unified architecture for selecting methods for obtaining Spectrum Availability information taking into account the operational environment and underlying policies. In addition, a novel low complexity heuristic decision making method is presented for selecting the Spectrum sensing technique taking into account different capabilities and requirements while being adaptable to the changing environment.

  • VTC Spring - Architecture and Approach for Obtaining Spectrum Availability Information
    2011 IEEE 73rd Vehicular Technology Conference (VTC Spring), 2011
    Co-Authors: Marja Matinmikko, Tapio Rauma, Miia Mustonen, Javier Del Ser
    Abstract:

    This paper presents a novel architecture and approach for obtaining Spectrum Availability information in future cognitive radio systems (CRS). CRS can opportunistically access Spectrum by identifying unoccupied channels while keeping higher priority systems on the same channel free from harmful interference. Knowledge of the current state of the Spectrum use is of utmost importance for CRS operations. There are different techniques for obtaining Spectrum Availability information including e.g. cognitive pilot channels, databases, Spectrum sensing techniques, and combinations thereof. For Spectrum sensing there are different algorithms and cooperative combining techniques with different characteristics and capabilities in terms of e.g. performance, complexity, and requirement of a priori information. This paper presents a unified architecture for selecting methods for obtaining Spectrum Availability information taking into account the operational environment and underlying policies. In addition, a novel low complexity heuristic decision making method is presented for selecting the Spectrum sensing technique taking into account different capabilities and requirements while being adaptable to the changing environment.