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Mingxuan Sun - One of the best experts on this subject based on the ideXlab platform.

  • on demand receiver centric channel allocation via constrained vcg auction for spatial Spectrum Reuse
    IEEE Systems Journal, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse significantly enhances Spectrum utilization but requires delicate design to avoid cochannel interference. Instead of focusing solely on Spectrum efficiency, we consider maximizing social welfare via channel allocation. Specifically, we propose an on-demand receiver-centric mechanism with a new factor, the supply and demand relationship. The optimal channel allocation that maximizes social welfare can be achieved by the constrained Vickrey–Clarke–Groves (VCG) auction for secondary users (SUs), but with high complexity. To simplify the constrained VCG auction, we group the SUs into maximal independent groups (MIGs) using a modified Bron–Kerbosch algorithm. We prove that truthful bidding is the optimal strategy for the SUs even though they do not participate in the VCG auction for MIGs directly. Therefore, the MIGs are bidding truthfully and social welfare is maximized. We also prove that the optimal channel allocation is not unique and thus a weakly-dominant strategy for the primary user, and the VCG style pricing based on truthful bidding can be implemented by using a decision tree repeatedly. Furthermore, we approximate and simplify the optimal channel allocation with a greedy algorithm, Dijkstra's algorithm, and batch allocation. In our simulation, we compare the proposed methods and demonstrate that on-demand channel allocation increases social welfare.

  • constrained vcg auction with multi level channel valuations for spatial Spectrum Reuse in non symmetric networks
    IEEE Transactions on Communications, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse enables better utilization of limited spectral resources to achieve higher system throughput. However, improving the system throughput or Spectrum efficiency does not necessarily translate to the satisfaction of more secondary users (SUs) according to their demands. To improve user satisfaction, user characteristics involving the supply and demand relationship need to be considered and thus enable heterogeneous channel valuations in spatial Spectrum Reuse. In this paper, we design a channel transaction mechanism for non-symmetric networks and maximize user satisfaction in consideration of multi-level flexible channel valuations of the SUs. Specifically, we introduce a Vickrey–Clarke–Groves (VCG) auction, in which the participants are limited to the allowable user crowds. To facilitate the bid formation, we transform the constrained VCG auction to a step-by-step decision process. Meanwhile, the SUs in a coalition play a coalitional game with transferable utilities. We use the Shapley value to realize fair payoff distribution among the SUs in a coalition. Furthermore, we approach the optimal channel allocation via finding the longest path in a directed acyclic graph, a greedy algorithm, and batch allocation. In our simulation, we compare the low-complexity algorithms and demonstrate the efficiency of the channel transaction mechanism.

  • multi level channel valuations and coalitional subgames in spatial Spectrum Reuse
    Consumer Communications and Networking Conference, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    To enable heterogeneous channel valuations in spatial Spectrum Reuse, user characteristics involving the supply and demand relationship need to be considered. In this paper, we design a channel transaction mechanism for non-symmetric networks and maximize the social welfare in consideration of multi-level channel valuations of the secondary users (SUs). Specifically, we group the SUs into allowable user crowds (AUCs) through a modified Bron-Kerbosch algorithm. We introduce a Vickrey-Clarke-Groves (VCG) auction, in which the participants are limited to the AUCs. To facilitate the bid formation, we transform the constrained VCG auction to a step-by-step decision process. In each step, the truthful bidding of an AUC is to reveal the accumulated channel valuation of the coalition. Meanwhile, the SUs in a coalition play a coalitional game with transferable utilities. We use the Shapley value to realize fair payoff distribution among the SUs in a coalition. Furthermore, we approach the optimal channel allocation via a greedy algorithm and batch allocation. In our simulation, we compare the low-complexity algorithms and demonstrate the efficiency of the channel transaction mechanism.

  • constrained vcg auction for spatial Spectrum Reuse with flexible channel evaluations
    Global Communications Conference, 2017
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse significantly enhances Spectrum utilization but requires delicate design to avoid co-channel interference. Instead of focusing solely on Spectrum efficiency, we consider maximizing social welfare via on-demand channel allocation in this paper. We design a Spectrum Reuse mechanism for non-symmetric networks, in which the optimal channel allocation that maximizes social welfare is the result of an appropriate bidding method of secondary users (SUs) in the constrained Vickrey-Clarke-Groves (VCG) auction. To simplify the constrained VCG auction, we group the SUs into interference-free maximal independent groups (MIGs) using a modified Bron-Kerbosch algorithm. We introduce the VCG auction for MIGs, in which truthful bidding is the optimal strategy for the MIGs. We build a decision process such that the MIGs as representatives of the SUs can update their channel evaluations in each step and submit truthful bids. Furthermore, we approximate and simplify the optimal channel allocation with a greedy algorithm and Dijkstra's algorithm. In our simulation, we compare the proposed methods and demonstrate that our on- demand channel allocation increases social welfare.

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

  • on demand receiver centric channel allocation via constrained vcg auction for spatial Spectrum Reuse
    IEEE Systems Journal, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse significantly enhances Spectrum utilization but requires delicate design to avoid cochannel interference. Instead of focusing solely on Spectrum efficiency, we consider maximizing social welfare via channel allocation. Specifically, we propose an on-demand receiver-centric mechanism with a new factor, the supply and demand relationship. The optimal channel allocation that maximizes social welfare can be achieved by the constrained Vickrey–Clarke–Groves (VCG) auction for secondary users (SUs), but with high complexity. To simplify the constrained VCG auction, we group the SUs into maximal independent groups (MIGs) using a modified Bron–Kerbosch algorithm. We prove that truthful bidding is the optimal strategy for the SUs even though they do not participate in the VCG auction for MIGs directly. Therefore, the MIGs are bidding truthfully and social welfare is maximized. We also prove that the optimal channel allocation is not unique and thus a weakly-dominant strategy for the primary user, and the VCG style pricing based on truthful bidding can be implemented by using a decision tree repeatedly. Furthermore, we approximate and simplify the optimal channel allocation with a greedy algorithm, Dijkstra's algorithm, and batch allocation. In our simulation, we compare the proposed methods and demonstrate that on-demand channel allocation increases social welfare.

  • constrained vcg auction with multi level channel valuations for spatial Spectrum Reuse in non symmetric networks
    IEEE Transactions on Communications, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse enables better utilization of limited spectral resources to achieve higher system throughput. However, improving the system throughput or Spectrum efficiency does not necessarily translate to the satisfaction of more secondary users (SUs) according to their demands. To improve user satisfaction, user characteristics involving the supply and demand relationship need to be considered and thus enable heterogeneous channel valuations in spatial Spectrum Reuse. In this paper, we design a channel transaction mechanism for non-symmetric networks and maximize user satisfaction in consideration of multi-level flexible channel valuations of the SUs. Specifically, we introduce a Vickrey–Clarke–Groves (VCG) auction, in which the participants are limited to the allowable user crowds. To facilitate the bid formation, we transform the constrained VCG auction to a step-by-step decision process. Meanwhile, the SUs in a coalition play a coalitional game with transferable utilities. We use the Shapley value to realize fair payoff distribution among the SUs in a coalition. Furthermore, we approach the optimal channel allocation via finding the longest path in a directed acyclic graph, a greedy algorithm, and batch allocation. In our simulation, we compare the low-complexity algorithms and demonstrate the efficiency of the channel transaction mechanism.

  • multi level channel valuations and coalitional subgames in spatial Spectrum Reuse
    Consumer Communications and Networking Conference, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    To enable heterogeneous channel valuations in spatial Spectrum Reuse, user characteristics involving the supply and demand relationship need to be considered. In this paper, we design a channel transaction mechanism for non-symmetric networks and maximize the social welfare in consideration of multi-level channel valuations of the secondary users (SUs). Specifically, we group the SUs into allowable user crowds (AUCs) through a modified Bron-Kerbosch algorithm. We introduce a Vickrey-Clarke-Groves (VCG) auction, in which the participants are limited to the AUCs. To facilitate the bid formation, we transform the constrained VCG auction to a step-by-step decision process. In each step, the truthful bidding of an AUC is to reveal the accumulated channel valuation of the coalition. Meanwhile, the SUs in a coalition play a coalitional game with transferable utilities. We use the Shapley value to realize fair payoff distribution among the SUs in a coalition. Furthermore, we approach the optimal channel allocation via a greedy algorithm and batch allocation. In our simulation, we compare the low-complexity algorithms and demonstrate the efficiency of the channel transaction mechanism.

  • constrained vcg auction for spatial Spectrum Reuse with flexible channel evaluations
    Global Communications Conference, 2017
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse significantly enhances Spectrum utilization but requires delicate design to avoid co-channel interference. Instead of focusing solely on Spectrum efficiency, we consider maximizing social welfare via on-demand channel allocation in this paper. We design a Spectrum Reuse mechanism for non-symmetric networks, in which the optimal channel allocation that maximizes social welfare is the result of an appropriate bidding method of secondary users (SUs) in the constrained Vickrey-Clarke-Groves (VCG) auction. To simplify the constrained VCG auction, we group the SUs into interference-free maximal independent groups (MIGs) using a modified Bron-Kerbosch algorithm. We introduce the VCG auction for MIGs, in which truthful bidding is the optimal strategy for the MIGs. We build a decision process such that the MIGs as representatives of the SUs can update their channel evaluations in each step and submit truthful bids. Furthermore, we approximate and simplify the optimal channel allocation with a greedy algorithm and Dijkstra's algorithm. In our simulation, we compare the proposed methods and demonstrate that our on- demand channel allocation increases social welfare.

Xiangwei Zhou - One of the best experts on this subject based on the ideXlab platform.

  • on demand receiver centric channel allocation via constrained vcg auction for spatial Spectrum Reuse
    IEEE Systems Journal, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse significantly enhances Spectrum utilization but requires delicate design to avoid cochannel interference. Instead of focusing solely on Spectrum efficiency, we consider maximizing social welfare via channel allocation. Specifically, we propose an on-demand receiver-centric mechanism with a new factor, the supply and demand relationship. The optimal channel allocation that maximizes social welfare can be achieved by the constrained Vickrey–Clarke–Groves (VCG) auction for secondary users (SUs), but with high complexity. To simplify the constrained VCG auction, we group the SUs into maximal independent groups (MIGs) using a modified Bron–Kerbosch algorithm. We prove that truthful bidding is the optimal strategy for the SUs even though they do not participate in the VCG auction for MIGs directly. Therefore, the MIGs are bidding truthfully and social welfare is maximized. We also prove that the optimal channel allocation is not unique and thus a weakly-dominant strategy for the primary user, and the VCG style pricing based on truthful bidding can be implemented by using a decision tree repeatedly. Furthermore, we approximate and simplify the optimal channel allocation with a greedy algorithm, Dijkstra's algorithm, and batch allocation. In our simulation, we compare the proposed methods and demonstrate that on-demand channel allocation increases social welfare.

  • constrained vcg auction with multi level channel valuations for spatial Spectrum Reuse in non symmetric networks
    IEEE Transactions on Communications, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse enables better utilization of limited spectral resources to achieve higher system throughput. However, improving the system throughput or Spectrum efficiency does not necessarily translate to the satisfaction of more secondary users (SUs) according to their demands. To improve user satisfaction, user characteristics involving the supply and demand relationship need to be considered and thus enable heterogeneous channel valuations in spatial Spectrum Reuse. In this paper, we design a channel transaction mechanism for non-symmetric networks and maximize user satisfaction in consideration of multi-level flexible channel valuations of the SUs. Specifically, we introduce a Vickrey–Clarke–Groves (VCG) auction, in which the participants are limited to the allowable user crowds. To facilitate the bid formation, we transform the constrained VCG auction to a step-by-step decision process. Meanwhile, the SUs in a coalition play a coalitional game with transferable utilities. We use the Shapley value to realize fair payoff distribution among the SUs in a coalition. Furthermore, we approach the optimal channel allocation via finding the longest path in a directed acyclic graph, a greedy algorithm, and batch allocation. In our simulation, we compare the low-complexity algorithms and demonstrate the efficiency of the channel transaction mechanism.

  • multi level channel valuations and coalitional subgames in spatial Spectrum Reuse
    Consumer Communications and Networking Conference, 2019
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    To enable heterogeneous channel valuations in spatial Spectrum Reuse, user characteristics involving the supply and demand relationship need to be considered. In this paper, we design a channel transaction mechanism for non-symmetric networks and maximize the social welfare in consideration of multi-level channel valuations of the secondary users (SUs). Specifically, we group the SUs into allowable user crowds (AUCs) through a modified Bron-Kerbosch algorithm. We introduce a Vickrey-Clarke-Groves (VCG) auction, in which the participants are limited to the AUCs. To facilitate the bid formation, we transform the constrained VCG auction to a step-by-step decision process. In each step, the truthful bidding of an AUC is to reveal the accumulated channel valuation of the coalition. Meanwhile, the SUs in a coalition play a coalitional game with transferable utilities. We use the Shapley value to realize fair payoff distribution among the SUs in a coalition. Furthermore, we approach the optimal channel allocation via a greedy algorithm and batch allocation. In our simulation, we compare the low-complexity algorithms and demonstrate the efficiency of the channel transaction mechanism.

  • constrained vcg auction for spatial Spectrum Reuse with flexible channel evaluations
    Global Communications Conference, 2017
    Co-Authors: Feixiang Zhang, Xiangwei Zhou, Mingxuan Sun
    Abstract:

    Spatial Spectrum Reuse significantly enhances Spectrum utilization but requires delicate design to avoid co-channel interference. Instead of focusing solely on Spectrum efficiency, we consider maximizing social welfare via on-demand channel allocation in this paper. We design a Spectrum Reuse mechanism for non-symmetric networks, in which the optimal channel allocation that maximizes social welfare is the result of an appropriate bidding method of secondary users (SUs) in the constrained Vickrey-Clarke-Groves (VCG) auction. To simplify the constrained VCG auction, we group the SUs into interference-free maximal independent groups (MIGs) using a modified Bron-Kerbosch algorithm. We introduce the VCG auction for MIGs, in which truthful bidding is the optimal strategy for the MIGs. We build a decision process such that the MIGs as representatives of the SUs can update their channel evaluations in each step and submit truthful bids. Furthermore, we approximate and simplify the optimal channel allocation with a greedy algorithm and Dijkstra's algorithm. In our simulation, we compare the proposed methods and demonstrate that our on- demand channel allocation increases social welfare.

Zhisheng Niu - One of the best experts on this subject based on the ideXlab platform.

  • improving the energy efficiency of two tier heterogeneous cellular networks through partial Spectrum Reuse
    IEEE Transactions on Wireless Communications, 2013
    Co-Authors: Dongxu Cao, Sheng Zhou, Zhisheng Niu
    Abstract:

    Partial Spectrum Reuse (PSR) in the second tier of two-tier heterogeneous cellular networks has a potential to improve Spectrum efficiency by reducing inter-cell interference, and thus energy efficiency as well by deploying less or switching off more Base Stations (BSs). In this paper, we analyze the optimal PSR factor, defined as the portion of Spectrum Reused by micro cells in two-tier heterogeneous networks, which is not in an explicit form generally. Then, a closed-form limit of the optimal PSR factor is derived as the ratio of the user rate requirement over the whole system Spectrum bandwidth is approaching zero, based on which a threshold of the micro-BS energy cost is also derived to determine which type of BSs is preferable. Specifically, one should deploy more micro BSs or switch off more macro BSs if the micro-BS energy cost is lower than the threshold. Otherwise, the optimal choice is the opposite. This threshold with the PSR scheme is higher than that without PSR scheme, i.e., PSR can improve both Spectrum efficiency and energy efficiency. Numerical results show that adopting PSR can reduce the network energy consumption by up to 50% when the transmit power of macro BSs is 10dB higher than that of micro BSs.

  • β psr a partial Spectrum Reuse scheme for two tier heterogeneous cellular networks
    International Conference on Communications, 2012
    Co-Authors: Dongxu Cao, Sheng Zhou, Zhisheng Niu
    Abstract:

    In this paper, we consider a Partial Spectrum Reuse (PSR) scheme, namely “β-PSR”, to improve Spectrum efficiency of two-tier heterogeneous cellular networks, in which each micro Base Station (BS) occupies a uniform portion β of the whole system Spectrum randomly and independently. We analyze the optimal PSR factor β to minimize service outage probability, which is not in an explicit form. Then a closed-form limit of the PSR factor is derived when the ratio of the user data rate requirement over the system bandwidth is approaching zero. This limit is an explicit function of the traffic intensity, the macro/micro BS density and their transmit power. Our numerical results also show that for most current rate requirements, the optimal PSR factor is well approximated by our derived limit. This motivates the design of an adaptive PSR scheme with near-optimal performance, which only depends on statistical network information.1.

David Lopezperez - One of the best experts on this subject based on the ideXlab platform.

  • ultra dense networks is there a limit to spatial Spectrum Reuse
    International Conference on Communications, 2018
    Co-Authors: Ming Ding, David Lopezperez, Guoqiang Mao, Zihuai Lin
    Abstract:

    The aggressive spatial Spectrum Reuse (SSR) by network densification using smaller cells has successfully driven the wireless communication industry onward in the past decades. In our future journey toward ultra-dense networks (UDNs), a fundamental question needs to be answered. Is there a limit to SSR? In other words, when we deploy thousands or millions of small cell base stations (BSs) per square kilometer, is activating all BSs on the same time/frequency resource the best strategy? In this paper, we present theoretical analyses to answer such question. In particular, we find that both the signal and interference powers become bounded in practical UDNs with a non-zero BS-to-UE antenna height difference and a finite UE density, which leads to a constant capacity scaling law. As a result, there exists an optimal SSR density that can maximize the network capacity. Hence, the limit to SSR should be considered in the operation of future UDNs.

  • dynamic Reuse of unlicensed Spectrum an inter working of lte and wifi
    IEEE Wireless Communications, 2017
    Co-Authors: Youjia Chen, David Lopezperez, Ming Ding, Zihuai Lin, Branka Vucetic
    Abstract:

    The dynamic exploitation of unlicensed Spectrum by mobile operators is becoming a trend of future 5G networks, with several efficient solutions being standardized for enabling Spectrum sharing. Solutions with various design philosophies diversify the network architectures and protocols. Among them, LAA aims at the physical-layer coexistence of LTE and WiFi within the unlicensed Spectrum, while LWA and LWIP focus on aggregating the link capacity of LTE in the licensed Spectrum and WiFi in the unlicensed one. In this article, a comprehensive survey of these three Spectrum sharing technologies are provided. Moreover, a novel analytical framework is proposed to evaluate the network performance of these technologies by incorporating both spatial and time domain analyses and integrating different types of cells in one network as a whole. Simulation results are provided to compare the system throughput of these Spectrum Reuse technologies.

  • enhanced intercell interference coordination challenges in heterogeneous networks
    IEEE Wireless Communications, 2011
    Co-Authors: David Lopezperez, Marios Kountouris, Tony Q.s. Quek, Ismail Guvenc, Jie Zhang
    Abstract:

    3GPP LTE-Advanced has recently been investigating heterogeneous network (HetNet) deployments as a cost effective way to deal with the unrelenting traffic demand. HetNets consist of a mix of macrocells, remote radio heads, and low-power nodes such as picocells, femtocells, and relays. Leveraging network topology, increasing the proximity between the access network and the end users, has the potential to provide the next significant performance leap in wireless networks, improving spatial Spectrum Reuse and enhancing indoor coverage. Nevertheless, deployment of a large number of small cells overlaying the macrocells is not without new technical challenges. In this article, we present the concept of heterogeneous networks and also describe the major technical challenges associated with such network architecture. We focus in particular on the standardization activities within the 3GPP related to enhanced intercell interference coordination.