The Experts below are selected from a list of 60 Experts worldwide ranked by ideXlab platform

M. K. Awad - One of the best experts on this subject based on the ideXlab platform.

  • A Dual-Decomposition-Based Resource Allocation for OFDMA Networks With Imperfect CSI
    IEEE Transactions on Vehicular Technology, 2010
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper presents a novel scheme for the Allocation of subcarriers, rates, and power in orthogonal frequency-division multiple-access (OFDMA) networks. The scheme addresses practical implementation issues of Resource Allocation in OFDMA networks: the inaccuracy of channel-state information (CSI) available to the Resource Allocation Unit (RAU) and the diversity of subscribers' quality-of-service (QoS) requirements. In addition to embedding the effect of CSI imperfection in the evaluation of the subscribers' expected rate, the Resource-Allocation problem is posed as a network utility maximization (NUM) one that is solved via decomposing it into a hierarchy of subproblems. These subproblems coordinate their Allocations to achieve a final Allocation that satisfies aggregate rate constraints imposed by the call-admission control (CAC) Unit and OFDMA-related constraints. A complexity analysis shows that the proposed scheme is computationally efficient. In addition, performance evaluation findings support our theoretical claims: A substantial data rate gain can be achieved by considering the CSI imperfection, and multiservice classes can be supported with QoS guarantees.

  • Downlink Resource Allocation for OFDMA-Based Multiservice Networks with Imperfect CSI
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper addresses practical implementation issues of Resource Allocation in OFDM A networks: inaccuracy of channel state information (CSI) available to the Resource Allocation Unit (RAU) and diversity of subscribers' quality of service (QoS) requirements. The Resource Allocation problem in the considered point-to-multipoint (PMP) network is modeled as a network utility maximization (NUM) problem that allocates subcarriers, rate and power while satisfying orthogonal frequency division multiple access (OFDMA) constraints and QoS constraints defined in the service level agreement. Performance evaluation findings support our theoretical claims: a substantial data rate gain is achieved by considering the CSI imperfection and multiservice classes are supported with QoS guarantees by coordinating with a call admission control (CAC) scheme.

  • ICC - Downlink Resource Allocation for OFDMA-Based Multiservice Networks with Imperfect CSI
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper addresses practical implementation issues of Resource Allocation in OFDMA networks: inaccuracy of channel state information (CSI) available to the Resource Allocation Unit (RAU) and diversity of subscribers' quality of service (QoS) requirements. The Resource Allocation problem in the considered point-to-multipoint (PMP) network is modeled as a network utility maximization (NUM) problem that allocates subcarriers, rate and power while satisfying orthogonal frequency division multiple access (OFDMA) constraints and QoS constraints defined in the service level agreement. Performance evaluation findings support our theoretical claims: a substantial data rate gain is achieved by considering the CSI imperfection and multiservice classes are supported with QoS guarantees by coordinating with a call admission control (CAC) scheme.

  • GLOBECOM - Uplink Ergodic Mutual Information of OFDMA-Based Two-Hop Cooperative Relay Networks with Imperfect CSI
    IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, 2008
    Co-Authors: M. K. Awad, X. Shen, Bashar Zogheib
    Abstract:

    This paper analyzes the ergodic mutual information of OFDMA cooperative relay networks when the Channel State Information (CSI) imperfection is considered at Resource Allocation Unit. Based on the derived ergodic mutual information, a quantitative characterization of the impact of CSI inaccuracy on the ergodic mutual information is presented. A network with multiple subscriber stations, relay stations and one base station that employ a Selection-Decode-and-Forward (SDF) relaying scheme is considered in the uplink mode. Subscriber stations act as relay stations to assist other transmitting subscriber stations. Numerical evaluations illustrate that considering the CSI imperfection based on priori knowledge of the error statistics brings substantial gain to the network in terms of ergodic mutual information, and takes the MAC layer Resource Allocation algorithms a step ahead towards practical implementations.

  • Uplink Ergodic Mutual Information of OFDMA-Based Two-Hop Cooperative Relay Networks with Imperfect CSI
    IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, 2008
    Co-Authors: M. K. Awad, X. Shen, Bashar Zogheib
    Abstract:

    This paper analyzes the ergodic mutual information of OFDMA cooperative relay networks when the Channel State Information (CSI) imperfection is considered at Resource Allocation Unit. Based on the derived ergodic mutual information, a quantitative characterization of the impact of CSI inaccuracy on the ergodic mutual information is presented. A network with multiple subscriber stations, relay stations and one base station that employ a Selection-Decode-and-Forward (SDF) relaying scheme is considered in the uplink mode. Subscriber stations act as relay stations to assist other transmitting subscriber stations. Numerical evaluations illustrate that considering the CSI imperfection based on priori knowledge of the error statistics brings substantial gain to the network in terms of ergodic mutual information, and takes the MAC layer Resource Allocation algorithms a step ahead towards practical implementations.

Seong Keun Oh - One of the best experts on this subject based on the ideXlab platform.

  • APCC - On Resource block sharing in 3GPP-LTE system
    The 17th Asia Pacific Conference on Communications, 2011
    Co-Authors: Seong Keun Oh
    Abstract:

    In this paper, we deal with sharing of a Resource block (RB) which is the basic Resource Allocation Unit for scheduling in 3rd-generation partnership project long term evolution (3GPP-LTE) system. In 3GPP-LTE system, a scheduler of evolved node-B (eNB) allocates respectively one or more RBs to user-equipments (UEs) considered, considering their requests, their channel qualities, and the Resource availability. In the case of constant-rate service (i.e., the real-time service), some of RBs may not be fully utilized, depending on the channel quality. Especially, in the case of multiple-input multiple-output (MIMO) multiplexing, the degree of Resource wastage may become much severer since a much less amount of the Resource may be required for the same data rate. In this paper, we introduce the concept of RB sharing where one RB can be shared by multiple UEs depending on their respective required rates and the corresponding channel qualities. Through computer simulations, we evaluate the average sum rates for both cases of RB sharing and non-sharing. From simulation results, we see that the RB sharing scheme can achieve much greater sum rate as compared to the non-sharing one.

  • On Resource block sharing in 3GPP-LTE system
    The 17th Asia Pacific Conference on Communications, 2011
    Co-Authors: Seong Keun Oh
    Abstract:

    In this paper, we deal with sharing of a Resource block (RB) which is the basic Resource Allocation Unit for scheduling in 3rd-generation partnership project long term evolution (3GPP-LTE) system. In 3GPP-LTE system, a scheduler of evolved node-B (eNB) allocates respectively one or more RBs to user-equipments (UEs) considered, considering their requests, their channel qualities, and the Resource availability. In the case of constant-rate service (i.e., the real-time service), some of RBs may not be fully utilized, depending on the channel quality. Especially, in the case of multiple-input multiple-output (MIMO) multiplexing, the degree of Resource wastage may become much severer since a much less amount of the Resource may be required for the same data rate. In this paper, we introduce the concept of RB sharing where one RB can be shared by multiple UEs depending on their respective required rates and the corresponding channel qualities. Through computer simulations, we evaluate the average sum rates for both cases of RB sharing and non-sharing. From simulation results, we see that the RB sharing scheme can achieve much greater sum rate as compared to the non-sharing one.

X. Shen - One of the best experts on this subject based on the ideXlab platform.

  • A Dual-Decomposition-Based Resource Allocation for OFDMA Networks With Imperfect CSI
    IEEE Transactions on Vehicular Technology, 2010
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper presents a novel scheme for the Allocation of subcarriers, rates, and power in orthogonal frequency-division multiple-access (OFDMA) networks. The scheme addresses practical implementation issues of Resource Allocation in OFDMA networks: the inaccuracy of channel-state information (CSI) available to the Resource Allocation Unit (RAU) and the diversity of subscribers' quality-of-service (QoS) requirements. In addition to embedding the effect of CSI imperfection in the evaluation of the subscribers' expected rate, the Resource-Allocation problem is posed as a network utility maximization (NUM) one that is solved via decomposing it into a hierarchy of subproblems. These subproblems coordinate their Allocations to achieve a final Allocation that satisfies aggregate rate constraints imposed by the call-admission control (CAC) Unit and OFDMA-related constraints. A complexity analysis shows that the proposed scheme is computationally efficient. In addition, performance evaluation findings support our theoretical claims: A substantial data rate gain can be achieved by considering the CSI imperfection, and multiservice classes can be supported with QoS guarantees.

  • Downlink Resource Allocation for OFDMA-Based Multiservice Networks with Imperfect CSI
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper addresses practical implementation issues of Resource Allocation in OFDM A networks: inaccuracy of channel state information (CSI) available to the Resource Allocation Unit (RAU) and diversity of subscribers' quality of service (QoS) requirements. The Resource Allocation problem in the considered point-to-multipoint (PMP) network is modeled as a network utility maximization (NUM) problem that allocates subcarriers, rate and power while satisfying orthogonal frequency division multiple access (OFDMA) constraints and QoS constraints defined in the service level agreement. Performance evaluation findings support our theoretical claims: a substantial data rate gain is achieved by considering the CSI imperfection and multiservice classes are supported with QoS guarantees by coordinating with a call admission control (CAC) scheme.

  • ICC - Downlink Resource Allocation for OFDMA-Based Multiservice Networks with Imperfect CSI
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper addresses practical implementation issues of Resource Allocation in OFDMA networks: inaccuracy of channel state information (CSI) available to the Resource Allocation Unit (RAU) and diversity of subscribers' quality of service (QoS) requirements. The Resource Allocation problem in the considered point-to-multipoint (PMP) network is modeled as a network utility maximization (NUM) problem that allocates subcarriers, rate and power while satisfying orthogonal frequency division multiple access (OFDMA) constraints and QoS constraints defined in the service level agreement. Performance evaluation findings support our theoretical claims: a substantial data rate gain is achieved by considering the CSI imperfection and multiservice classes are supported with QoS guarantees by coordinating with a call admission control (CAC) scheme.

  • GLOBECOM - Uplink Ergodic Mutual Information of OFDMA-Based Two-Hop Cooperative Relay Networks with Imperfect CSI
    IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, 2008
    Co-Authors: M. K. Awad, X. Shen, Bashar Zogheib
    Abstract:

    This paper analyzes the ergodic mutual information of OFDMA cooperative relay networks when the Channel State Information (CSI) imperfection is considered at Resource Allocation Unit. Based on the derived ergodic mutual information, a quantitative characterization of the impact of CSI inaccuracy on the ergodic mutual information is presented. A network with multiple subscriber stations, relay stations and one base station that employ a Selection-Decode-and-Forward (SDF) relaying scheme is considered in the uplink mode. Subscriber stations act as relay stations to assist other transmitting subscriber stations. Numerical evaluations illustrate that considering the CSI imperfection based on priori knowledge of the error statistics brings substantial gain to the network in terms of ergodic mutual information, and takes the MAC layer Resource Allocation algorithms a step ahead towards practical implementations.

  • Uplink Ergodic Mutual Information of OFDMA-Based Two-Hop Cooperative Relay Networks with Imperfect CSI
    IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, 2008
    Co-Authors: M. K. Awad, X. Shen, Bashar Zogheib
    Abstract:

    This paper analyzes the ergodic mutual information of OFDMA cooperative relay networks when the Channel State Information (CSI) imperfection is considered at Resource Allocation Unit. Based on the derived ergodic mutual information, a quantitative characterization of the impact of CSI inaccuracy on the ergodic mutual information is presented. A network with multiple subscriber stations, relay stations and one base station that employ a Selection-Decode-and-Forward (SDF) relaying scheme is considered in the uplink mode. Subscriber stations act as relay stations to assist other transmitting subscriber stations. Numerical evaluations illustrate that considering the CSI imperfection based on priori knowledge of the error statistics brings substantial gain to the network in terms of ergodic mutual information, and takes the MAC layer Resource Allocation algorithms a step ahead towards practical implementations.

J. W. Mark - One of the best experts on this subject based on the ideXlab platform.

  • A Dual-Decomposition-Based Resource Allocation for OFDMA Networks With Imperfect CSI
    IEEE Transactions on Vehicular Technology, 2010
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper presents a novel scheme for the Allocation of subcarriers, rates, and power in orthogonal frequency-division multiple-access (OFDMA) networks. The scheme addresses practical implementation issues of Resource Allocation in OFDMA networks: the inaccuracy of channel-state information (CSI) available to the Resource Allocation Unit (RAU) and the diversity of subscribers' quality-of-service (QoS) requirements. In addition to embedding the effect of CSI imperfection in the evaluation of the subscribers' expected rate, the Resource-Allocation problem is posed as a network utility maximization (NUM) one that is solved via decomposing it into a hierarchy of subproblems. These subproblems coordinate their Allocations to achieve a final Allocation that satisfies aggregate rate constraints imposed by the call-admission control (CAC) Unit and OFDMA-related constraints. A complexity analysis shows that the proposed scheme is computationally efficient. In addition, performance evaluation findings support our theoretical claims: A substantial data rate gain can be achieved by considering the CSI imperfection, and multiservice classes can be supported with QoS guarantees.

  • Downlink Resource Allocation for OFDMA-Based Multiservice Networks with Imperfect CSI
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper addresses practical implementation issues of Resource Allocation in OFDM A networks: inaccuracy of channel state information (CSI) available to the Resource Allocation Unit (RAU) and diversity of subscribers' quality of service (QoS) requirements. The Resource Allocation problem in the considered point-to-multipoint (PMP) network is modeled as a network utility maximization (NUM) problem that allocates subcarriers, rate and power while satisfying orthogonal frequency division multiple access (OFDMA) constraints and QoS constraints defined in the service level agreement. Performance evaluation findings support our theoretical claims: a substantial data rate gain is achieved by considering the CSI imperfection and multiservice classes are supported with QoS guarantees by coordinating with a call admission control (CAC) scheme.

  • ICC - Downlink Resource Allocation for OFDMA-Based Multiservice Networks with Imperfect CSI
    2009 IEEE International Conference on Communications, 2009
    Co-Authors: M. K. Awad, V. Mahinthan, M. Mehrjoo, X. Shen, J. W. Mark
    Abstract:

    This paper addresses practical implementation issues of Resource Allocation in OFDMA networks: inaccuracy of channel state information (CSI) available to the Resource Allocation Unit (RAU) and diversity of subscribers' quality of service (QoS) requirements. The Resource Allocation problem in the considered point-to-multipoint (PMP) network is modeled as a network utility maximization (NUM) problem that allocates subcarriers, rate and power while satisfying orthogonal frequency division multiple access (OFDMA) constraints and QoS constraints defined in the service level agreement. Performance evaluation findings support our theoretical claims: a substantial data rate gain is achieved by considering the CSI imperfection and multiservice classes are supported with QoS guarantees by coordinating with a call admission control (CAC) scheme.

Ji Wan Song - One of the best experts on this subject based on the ideXlab platform.

  • Networking - A novel Resource Allocation scheme for reducing MAP overhead and maximizing throughput in MIMO-OFDM systems
    NETWORKING 2006. Networking Technologies Services and Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communication, 2006
    Co-Authors: Kyung Ho Sohn, Ji Wan Song
    Abstract:

    We propose a novel Resource Allocation scheme, which can reduce MAP overhead and maximize the throughput in the MIMO-OFDM systems. In the message based broadband access system, we need to minimize the MAP overhead since the excessive MAP overhead causes degradation of system throughput. Increasing the size of Resource Allocation Unit can reduce MAP overhead. However, multiuser diversity gain becomes smaller as the size of re-source Allocation Unit increases. Therefore, we investigate joint optimization between multiuser diversity gain and MAP overhead size. Using the proposed scheme, we can reduce MAP overhead size as well as achieve high throughput.

  • WWIC - Scheme for joint optimization of MAP overhead and system throughput in message based MIMO-OFDM systems
    Lecture Notes in Computer Science, 2006
    Co-Authors: Kyung Ho Sohn, Ji Wan Song
    Abstract:

    We propose a novel Resource Allocation scheme, which can reduce MAP overhead and maximize the throughput in the MIMO-OFDM systems. Message based broadband access systems are needed to minimize the MAP overhead since the excessive MAP overhead causes degradation of system throughput. Increasing the size of Resource Allocation Unit can reduce MAP overhead. However, multiuser diversity gain becomes smaller as the size of Resource Allocation Unit increases. Therefore, we investigate joint optimization between multiuser diversity gain and MAP overhead size. The proposed scheme can reduce the MAP overhead size as well as achieve high throughput.