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Christian Cardinal - One of the best experts on this subject based on the ideXlab platform.

  • VTC Fall - On the Achievable Rate and Average Sum Capacity of Spread Spectrum Underlay CR Networks
    2016 IEEE 84th Vehicular Technology Conference (VTC-Fall), 2016
    Co-Authors: Saed Daoud, David Haccoun, Christian Cardinal
    Abstract:

    In this paper, we investigate the achievable rate and the average sum capacity of an Underlay cognitive radio (CR) (also known as a secondary) system. We consider single user (SU) and multiple users (MU) secondary systems that deploy spread Spectrum as the signaling technique which utilizes the whole available Spectrum. The objective is to maximize the achievable rate and the average sum capacity of the SU and MU secondary systems, respectively, by allocating the optimum power to the secondary transmitter(s) (STs), such that the instantaneous (aggregate) interference power from STs is below a certain threshold at the primary receiver (PR), to guarantee the quality of service (QoS) of the primary system. Numerical and Monte-Carlo Simulation results show that the achievable rate of the SU system and the average sum capacity of the MU system can be enhanced significantly compared to other signaling techniques, because of the fact that in spread Spectrum the signal's power is spread over a wider bandwidth, which gives the secondary system more freedom to allocate power to enhance the data rate.

  • On the Achievable Rate and Average Sum Capacity of Spread Spectrum Underlay CR Networks
    2016 IEEE 84th Vehicular Technology Conference (VTC-Fall), 2016
    Co-Authors: Saed Daoud, David Haccoun, Christian Cardinal
    Abstract:

    In this paper, we investigate the achievable rate and the average sum capacity of an Underlay cognitive radio (CR) (also known as a secondary) system. We consider single user (SU) and multiple users (MU) secondary systems that deploy spread Spectrum as the signaling technique which utilizes the whole available Spectrum. The objective is to maximize the achievable rate and the average sum capacity of the SU and MU secondary systems, respectively, by allocating the optimum power to the secondary transmitter(s) (STs), such that the instantaneous (aggregate) interference power from STs is below a certain threshold at the primary receiver (PR), to guarantee the quality of service (QoS) of the primary system. Numerical and Monte-Carlo Simulation results show that the achievable rate of the SU system and the average sum capacity of the MU system can be enhanced significantly compared to other signaling techniques, because of the fact that in spread Spectrum the signal's power is spread over a wider bandwidth, which gives the secondary system more freedom to allocate power to enhance the data rate.

Dongmei Zhao - One of the best experts on this subject based on the ideXlab platform.

  • joint connection admission control and packet scheduling in a cognitive radio network with Spectrum Underlay
    IEEE Transactions on Wireless Communications, 2011
    Co-Authors: Bin Wang, Dongmei Zhao, Jun Cai
    Abstract:

    With the increasing popularity of cognitive radio networks (CRNs), providing data transmissions with quality of service (QoS) requirements in such networks becomes one of the most important topics. In this paper we study QoS provisioning in an ad hoc CRN with Spectrum Underlay. Both streaming traffic and non-real-time (nrt) data traffic are considered. The former requires a low session outage probability and the latter requires a minimum average throughput. A joint connection admission and packet scheduling scheme is proposed in this paper. The connection admission control scheme limits the amount of traffic admitted into the system so that all admitted connections can receive their required QoS through the proposed packet scheduling schemes. Two packet transmission scheduling schemes are designed, one is optimum and assumes that a central controller can collect the global channel and interference conditions within the CRN and between the primary network and the CRN, while the other one is a heuristic scheme based on the link and interference conditions measured by the nodes in the CRN. In addition to achieving the required QoS, the scheduling schemes utilize the available radio resources fairly and efficiently. Numerical results demonstrate that when the traffic load at the primary network is relatively stationary, the proposed scheduling scheme can achieve very low and fair outage probability for all admitted streaming connections, and all admitted non-real-time data connections can receive the required throughput and fair delay performance.

  • admission control and packet scheduling in a cognitive radio network with Spectrum Underlay
    Global Communications Conference, 2010
    Co-Authors: Bin Wang, Dongmei Zhao, Jun Cai
    Abstract:

    In this paper we study quality-of-service (QoS) provisioning in an ad hoc cognitive radio network with Spectrum Underlay. Both streaming traffic and non-real-time (nrt) data traffic are considered. An admission control scheme is first proposed based on relatively static information such as path loss and average interference levels in order to guarantee the average throughput of each connection. Outage performance of the streaming traffic and throughput of the nrt traffic are managed through slot-by-slot packet transmission scheduling, which opportunistically takes advantage of the randomly varying channel and interference conditions. Numerical results demonstrate that very small outage probability can be achieved for the streaming traffic, and the non-real-time connections receive throughput higher than the minimum required.

  • Scheduling for long term proportional fairness in a cognitive wireless network with Spectrum Underlay
    IEEE Transactions on Wireless Communications, 2010
    Co-Authors: Bin Wang, Dongmei Zhao
    Abstract:

    In this paper we study fair rate scheduling in an ad hoc cognitive wireless network with Spectrum Underlay. Transmissions in the network are allowed provided their interference to the primary network is below a predefined threshold. An optimal scheduling problem is formulated with an objective to achieve proportional fairness (PF) of the long-term average transmission rates among different links. Implementing the optimum scheduling requires high complexity. Two practical scheduling schemes are then proposed. In the first scheme, transmission priorities of the links are determined by their potential contributions to an objective utility function, assuming there is no co-channel interference within the network. In the second scheme, transmission priorities are derived from both the objective function and interference to the primary network. We also consider using exclusive regions to limit interference among simultaneous transmissions in order to improve the system throughput. The scheduling schemes can be implemented distributively in the ad hoc cognitive wireless network with limited assistance from the primary network. Our results show that the proposed PF scheduling schemes can achieve high overall throughput and close-to-optimum fairness, and using exclusive regions can improve the system utility without compromising the fairness performance.

  • GLOBECOM - Admission Control and Packet Scheduling in a Cognitive Radio Network with Spectrum Underlay
    2010 IEEE Global Telecommunications Conference GLOBECOM 2010, 2010
    Co-Authors: Bin Wang, Dongmei Zhao, Jun Cai
    Abstract:

    In this paper we study quality-of-service (QoS) provisioning in an ad hoc cognitive radio network with Spectrum Underlay. Both streaming traffic and non-real-time (nrt) data traffic are considered. An admission control scheme is first proposed based on relatively static information such as path loss and average interference levels in order to guarantee the average throughput of each connection. Outage performance of the streaming traffic and throughput of the nrt traffic are managed through slot-by-slot packet transmission scheduling, which opportunistically takes advantage of the randomly varying channel and interference conditions. Numerical results demonstrate that very small outage probability can be achieved for the streaming traffic, and the non-real-time connections receive throughput higher than the minimum required.

  • long term fair scheduling in a cognitive wireless network with Spectrum Underlay
    Global Communications Conference, 2009
    Co-Authors: Bin Wang, Dongmei Zhao
    Abstract:

    In this paper we study fair rate scheduling in an ad hoc cognitive wireless network with Spectrum Underlay. Transmissions in the network are allowed provided their interference to the primary network is below a predefined threshold. An optimal scheduling problem is formulated with an objective to achieve proportional fairness (PF) of the long-term average transmission rates among different links in the network. Two scheduling schemes are proposed for achieving PF of the average rates, each using different criteria to make scheduling decisions. Both scheduling schemes can be implemented distributively in the ad hoc cognitive network with limited assistance from the primary network. Our results show that the proposed PF scheduling schemes can achieve high overall throughput and close-to-optimum fairness.

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

  • joint connection admission control and packet scheduling in a cognitive radio network with Spectrum Underlay
    IEEE Transactions on Wireless Communications, 2011
    Co-Authors: Bin Wang, Dongmei Zhao, Jun Cai
    Abstract:

    With the increasing popularity of cognitive radio networks (CRNs), providing data transmissions with quality of service (QoS) requirements in such networks becomes one of the most important topics. In this paper we study QoS provisioning in an ad hoc CRN with Spectrum Underlay. Both streaming traffic and non-real-time (nrt) data traffic are considered. The former requires a low session outage probability and the latter requires a minimum average throughput. A joint connection admission and packet scheduling scheme is proposed in this paper. The connection admission control scheme limits the amount of traffic admitted into the system so that all admitted connections can receive their required QoS through the proposed packet scheduling schemes. Two packet transmission scheduling schemes are designed, one is optimum and assumes that a central controller can collect the global channel and interference conditions within the CRN and between the primary network and the CRN, while the other one is a heuristic scheme based on the link and interference conditions measured by the nodes in the CRN. In addition to achieving the required QoS, the scheduling schemes utilize the available radio resources fairly and efficiently. Numerical results demonstrate that when the traffic load at the primary network is relatively stationary, the proposed scheduling scheme can achieve very low and fair outage probability for all admitted streaming connections, and all admitted non-real-time data connections can receive the required throughput and fair delay performance.

  • RADIO RESOURCE MANAGEMENT IN CDMA-BASED COGNITIVE AND COOPERATIVE NETWORKS
    2011
    Co-Authors: Bin Wang
    Abstract:

    In this thesis we study radio resource management (RRM) in two types of CDMAbased wireless networks, cognitive radio networks (CRNs) and cooperative communication networks. In the networks, all simultaneous transmissions share the same Spectrum and interfere with one another. Therefore, managing the transmission power is very important as it determines other aspects of the network resource allocations, such as transmission time and rate allocations. The main objective of the RRM is to efficiently utilize the available network resources for providing the mobile users with satisfactory quality of service (QoS). In Chapters 2-4, we study the resource management in a CDMA-based ad hoc CRN with Spectrum Underlay, where the CRN shares the same Spectrum with the uplink of a cellular CDMA network, which is the primary network. We first jointly consider the resource allocations in both the primary and the secondary networks, and study the optimum transmission power and rate allocations for supporting best effort traffic in the CRN. Fair transmission throughput is provided to the secondary links at each time slot. We then study how to support long-term best effort traffic in the CRN, and provide proportional fairness to the average throughput among links. An optimum scheduling problem is formulated and solved, and two heuristic

  • admission control and packet scheduling in a cognitive radio network with Spectrum Underlay
    Global Communications Conference, 2010
    Co-Authors: Bin Wang, Dongmei Zhao, Jun Cai
    Abstract:

    In this paper we study quality-of-service (QoS) provisioning in an ad hoc cognitive radio network with Spectrum Underlay. Both streaming traffic and non-real-time (nrt) data traffic are considered. An admission control scheme is first proposed based on relatively static information such as path loss and average interference levels in order to guarantee the average throughput of each connection. Outage performance of the streaming traffic and throughput of the nrt traffic are managed through slot-by-slot packet transmission scheduling, which opportunistically takes advantage of the randomly varying channel and interference conditions. Numerical results demonstrate that very small outage probability can be achieved for the streaming traffic, and the non-real-time connections receive throughput higher than the minimum required.

  • Scheduling for long term proportional fairness in a cognitive wireless network with Spectrum Underlay
    IEEE Transactions on Wireless Communications, 2010
    Co-Authors: Bin Wang, Dongmei Zhao
    Abstract:

    In this paper we study fair rate scheduling in an ad hoc cognitive wireless network with Spectrum Underlay. Transmissions in the network are allowed provided their interference to the primary network is below a predefined threshold. An optimal scheduling problem is formulated with an objective to achieve proportional fairness (PF) of the long-term average transmission rates among different links. Implementing the optimum scheduling requires high complexity. Two practical scheduling schemes are then proposed. In the first scheme, transmission priorities of the links are determined by their potential contributions to an objective utility function, assuming there is no co-channel interference within the network. In the second scheme, transmission priorities are derived from both the objective function and interference to the primary network. We also consider using exclusive regions to limit interference among simultaneous transmissions in order to improve the system throughput. The scheduling schemes can be implemented distributively in the ad hoc cognitive wireless network with limited assistance from the primary network. Our results show that the proposed PF scheduling schemes can achieve high overall throughput and close-to-optimum fairness, and using exclusive regions can improve the system utility without compromising the fairness performance.

  • GLOBECOM - Admission Control and Packet Scheduling in a Cognitive Radio Network with Spectrum Underlay
    2010 IEEE Global Telecommunications Conference GLOBECOM 2010, 2010
    Co-Authors: Bin Wang, Dongmei Zhao, Jun Cai
    Abstract:

    In this paper we study quality-of-service (QoS) provisioning in an ad hoc cognitive radio network with Spectrum Underlay. Both streaming traffic and non-real-time (nrt) data traffic are considered. An admission control scheme is first proposed based on relatively static information such as path loss and average interference levels in order to guarantee the average throughput of each connection. Outage performance of the streaming traffic and throughput of the nrt traffic are managed through slot-by-slot packet transmission scheduling, which opportunistically takes advantage of the randomly varying channel and interference conditions. Numerical results demonstrate that very small outage probability can be achieved for the streaming traffic, and the non-real-time connections receive throughput higher than the minimum required.

Saed Daoud - One of the best experts on this subject based on the ideXlab platform.

  • VTC Fall - On the Achievable Rate and Average Sum Capacity of Spread Spectrum Underlay CR Networks
    2016 IEEE 84th Vehicular Technology Conference (VTC-Fall), 2016
    Co-Authors: Saed Daoud, David Haccoun, Christian Cardinal
    Abstract:

    In this paper, we investigate the achievable rate and the average sum capacity of an Underlay cognitive radio (CR) (also known as a secondary) system. We consider single user (SU) and multiple users (MU) secondary systems that deploy spread Spectrum as the signaling technique which utilizes the whole available Spectrum. The objective is to maximize the achievable rate and the average sum capacity of the SU and MU secondary systems, respectively, by allocating the optimum power to the secondary transmitter(s) (STs), such that the instantaneous (aggregate) interference power from STs is below a certain threshold at the primary receiver (PR), to guarantee the quality of service (QoS) of the primary system. Numerical and Monte-Carlo Simulation results show that the achievable rate of the SU system and the average sum capacity of the MU system can be enhanced significantly compared to other signaling techniques, because of the fact that in spread Spectrum the signal's power is spread over a wider bandwidth, which gives the secondary system more freedom to allocate power to enhance the data rate.

  • On the Achievable Rate and Average Sum Capacity of Spread Spectrum Underlay CR Networks
    2016 IEEE 84th Vehicular Technology Conference (VTC-Fall), 2016
    Co-Authors: Saed Daoud, David Haccoun, Christian Cardinal
    Abstract:

    In this paper, we investigate the achievable rate and the average sum capacity of an Underlay cognitive radio (CR) (also known as a secondary) system. We consider single user (SU) and multiple users (MU) secondary systems that deploy spread Spectrum as the signaling technique which utilizes the whole available Spectrum. The objective is to maximize the achievable rate and the average sum capacity of the SU and MU secondary systems, respectively, by allocating the optimum power to the secondary transmitter(s) (STs), such that the instantaneous (aggregate) interference power from STs is below a certain threshold at the primary receiver (PR), to guarantee the quality of service (QoS) of the primary system. Numerical and Monte-Carlo Simulation results show that the achievable rate of the SU system and the average sum capacity of the MU system can be enhanced significantly compared to other signaling techniques, because of the fact that in spread Spectrum the signal's power is spread over a wider bandwidth, which gives the secondary system more freedom to allocate power to enhance the data rate.

P. C. Ching - One of the best experts on this subject based on the ideXlab platform.

  • A Power Allocation Strategy for Multiple Poisson Spectrum-Sharing Networks
    IEEE Transactions on Wireless Communications, 2015
    Co-Authors: Ran Cai, Wei Zhang, Jian-kang Zhang, Timothy N. Davidson, Kon Max Wong, P. C. Ching
    Abstract:

    This paper develops a power allocation strategy for multiple networks of Poisson-distributed single-antenna nodes that share the available Spectrum in a Spectrum Underlay scenario. This strategy aims to maximize the overall throughput obtained by sharing the Spectrum while limiting the degradation of the successful transmission probability of each network. In its original form, this joint power allocation problem is difficult to solve. However, we demonstrate that the problem can be transformed into a convex optimization formulation, which can be efficiently solved. Furthermore, we obtain a quasi-closed-form solution that has a water-filling interpretation by analyzing the optimality conditions. Numerical results indicate that, when a Spectrum-sharing scheme employs the proposed optimal strategy of power allocation, the throughput substantially improves over that obtained by exclusively allocating the Spectrum to the primary network. Moreover, when the number of Spectrum-sharing networks increases, the enhancement is significant, being up to the limit imposed by the maximum allowable degradation in the performance of each network.

  • ICASSP - Power control for multiple Spectrum-sharing networks under random geometric topologies
    2013 IEEE International Conference on Acoustics Speech and Signal Processing, 2013
    Co-Authors: Ran Cai, Jian-kang Zhang, Timothy N. Davidson, Kon Max Wong, P. C. Ching
    Abstract:

    This paper develops a power control strategy for multiple Spectrum-sharing networks of single antenna nodes in a Spectrum Underlay scenario. A distinguishing feature of the proposed strategy is that it requires only knowledge of the spatial distribution of the nodes, rather than instantaneous channel state information. The strategy seeks to maximize a weighted sum of the throughput of each network while guaranteeing specified successful transmission probabilities. In its native form, this joint power allocation problem is difficult to solve. However, we show that the problem can be transformed into a convex optimization formulation that can be efficiently solved using general purpose tools. Furthermore, we analyze the optimality conditions and obtain a quasi-closed form solution reminiscent of waterfilling. Numerical results demonstrate that Spectrum sharing employing the proposed optimal power yields a substantial throughput gain over allocating the Spectrum to a single network.