This letter studies cellular controlled short-range communication in OFDMA networks. The network ... more This letter studies cellular controlled short-range communication in OFDMA networks. The network needs to decide when to allow direct communication between a closely located device-to-device (D2D) pair instead of conveying data from one device to the other via the base station and when not to, in addition to subchannel and power allocation. Our goal is to maximize the total network throughput while guaranteeing the rate requirements of all users. For that purpose, we formulate an optimization problem subject to subchannel and power constraints. A scheme which combines a joint mode selection and subchannel allocation algorithm based on equal power allocation with a power reallocation scheme is proposed. Simulation results show that our proposed scheme can improve the network throughput and outage probability compared with other schemes.
In this paper, we investigate the dynamic user-AP association with QoS-aware CSMA in a virtualize... more In this paper, we investigate the dynamic user-AP association with QoS-aware CSMA in a virtualized wireless network. In particular, to efficiently support slice isolation, we consider an enhanced CSMA frame with two phases: a contention-free A-phase using CSMA with deterministic back-off, followed by a contention-based C-phase using p-persistent CSMA. The user scheduling in the contention-free A-phase and determination of p values for the contention-based C-phase along with the user-AP association are formulated as an optimization problem, aiming to maximize the overall network throughput under the slice isolation constraints and channel conditions. Subsequently, complementary geometric programming (CGP) and monomial approximations are used to develop an iterative algorithm for solution. Illustrative simulation results show the efficiency of the developed solution and its effect on network performance while maintaining the isolation among slices.
Abstract This paper presents an IP-based broadband satellite access (BSA) network architecture fo... more Abstract This paper presents an IP-based broadband satellite access (BSA) network architecture for interactive multimedia services with an emphasis on the return link. The functions and architectures of key BSA network components to provide IP Quality of ...
Abstract This paper presents a newly developed general traffic engineering (TE) evaluation platfo... more Abstract This paper presents a newly developed general traffic engineering (TE) evaluation platform, which facilitates the performance evaluation of various TE methodologies and techniques in QoS-aware DiffServ-MPLS networks and under different network topologies, ...
This paper considers a buffer-aided full-duplex (FD) relaying network assuming imperfect self-int... more This paper considers a buffer-aided full-duplex (FD) relaying network assuming imperfect self-interference (SI) cancellation. The residual SI level is modeled to be proportional to the relay transmit power. Moreover, for quality-of-service (QoS) provisioning, the end-to-end queue-length is statistically constrained in terms of maximum acceptable outage probability. We derive the optimal power allocation solution for the source and relay to maximize the constant supportable arrival rate μ to the source (i.e., the effective capacity) and study its properties. Illustrative examples are performed to compare the effective capacities of the proposed FD relaying scheme and other benchmark schemes under different settings and QoS constraints.
This paper develops Quality of Service (QoS) based routing and priority class assignment algorith... more This paper develops Quality of Service (QoS) based routing and priority class assignment algorithms using an end-to-end delay satisfaction balancing approach. Unlike the single-class delay satisfaction balancing optimization problem, the nonlinear multi-priority formulation is only convex ...
Springer briefs in electrical and computer engineering, 2017
Next-generation wireless systems are expected to support an ever increasing number of wireless co... more Next-generation wireless systems are expected to support an ever increasing number of wireless connections with better quality-of-service (QoS), e.g., higher data rate and smaller delay [1, 2]. As a result, energy consumption, as well as energy cost, and greenhouse gas emission are increased, which pose challenges in the design of wireless systems. One promising method to tackle this issue is energy harvesting (EH), where wireless nodes have the capability to harvest energy from the renewable sources (e.g., solar, and thermoelectric, etc.) of the surrounding environment, and store the harvested energy in batteries to carry out their functions. In this chapter, we explore power allocation problems for such EH systems to support delay-sensitive communications.
Springer briefs in electrical and computer engineering, 2017
In this chapter, we consider a point-to-point communications link over a fading channel with rand... more In this chapter, we consider a point-to-point communications link over a fading channel with randomly arriving data at the source buffer for transmission to the destination. For delay quality-of-service (QoS) requirement, (maximum) average delay constraint is imposed. Also, the source is assumed to have (maximum) average power constraint. To avoid constraint violation, it is assumed that only a portion of the arriving data can be buffered (or admitted). Note that the considered data buffer admission control is different from the common user (or stream) admission control. In the latter case, we admit a particular user (among many users) into the system while in the former, we admit data packets of an already admitted user (or stream) into the transmission buffer. Under such settings, this chapter studies the joint data admission control-power allocation (AC-PA) to maximize the throughput defined as the average admitted rate. In particular, we first analyze the structural properties of the optimal AC-PA policy with respect to fading channel, data arrival, and queue length states. We then propose an online AC-PA algorithm when the statistical knowledge of the system random channel fading, and data arrival processes is unknown.
REV Journal on Electronics and Communications, 2014
Neighbor area network (NAN), also known as smart meter communication network, is one of the most ... more Neighbor area network (NAN), also known as smart meter communication network, is one of the most important segments of smart grid communications network (SGCN). This paper studies the performance of greedy perimeter stateless routing (GPSR), a representative implementation of geographic-based routing class, in the NAN scenario and investigates the feasibility of this routing protocol in supporting SG applications. Specifically, packet transmission delay and reliability of GPSR in an IEEE 802.15.4-based wireless mesh NAN with practical system parameters are measured by simulations. The results show that, at the data rate required for conventional SG applications including smart metering, real-time pricing and demand response, the delay can always be maintained below 70 ms (in 95th-percentile perspective) while packet delivery ratio is higher than 90%. However, due to that fact that more advanced applications that require information exchange at higher rates and more stringent delays ...
CCECE 2003 - Canadian Conference on Electrical and Computer Engineering. Toward a Caring and Humane Technology (Cat. No.03CH37436), 2003
Abstract-The recent growth in Intemet trafic and services has made the provisioning of End-to-End... more Abstract-The recent growth in Intemet trafic and services has made the provisioning of End-to-End Qualiry of Service (QoS) in large-scale networkr a necessiw. Traffic Engineering (TE) emerges as an important constituent of QoS provisioning. This paper presents a ...
This letter studies cellular controlled short-range communication in OFDMA networks. The network ... more This letter studies cellular controlled short-range communication in OFDMA networks. The network needs to decide when to allow direct communication between a closely located device-to-device (D2D) pair instead of conveying data from one device to the other via the base station and when not to, in addition to subchannel and power allocation. Our goal is to maximize the total network throughput while guaranteeing the rate requirements of all users. For that purpose, we formulate an optimization problem subject to subchannel and power constraints. A scheme which combines a joint mode selection and subchannel allocation algorithm based on equal power allocation with a power reallocation scheme is proposed. Simulation results show that our proposed scheme can improve the network throughput and outage probability compared with other schemes.
In this paper, we investigate the dynamic user-AP association with QoS-aware CSMA in a virtualize... more In this paper, we investigate the dynamic user-AP association with QoS-aware CSMA in a virtualized wireless network. In particular, to efficiently support slice isolation, we consider an enhanced CSMA frame with two phases: a contention-free A-phase using CSMA with deterministic back-off, followed by a contention-based C-phase using p-persistent CSMA. The user scheduling in the contention-free A-phase and determination of p values for the contention-based C-phase along with the user-AP association are formulated as an optimization problem, aiming to maximize the overall network throughput under the slice isolation constraints and channel conditions. Subsequently, complementary geometric programming (CGP) and monomial approximations are used to develop an iterative algorithm for solution. Illustrative simulation results show the efficiency of the developed solution and its effect on network performance while maintaining the isolation among slices.
Abstract This paper presents an IP-based broadband satellite access (BSA) network architecture fo... more Abstract This paper presents an IP-based broadband satellite access (BSA) network architecture for interactive multimedia services with an emphasis on the return link. The functions and architectures of key BSA network components to provide IP Quality of ...
Abstract This paper presents a newly developed general traffic engineering (TE) evaluation platfo... more Abstract This paper presents a newly developed general traffic engineering (TE) evaluation platform, which facilitates the performance evaluation of various TE methodologies and techniques in QoS-aware DiffServ-MPLS networks and under different network topologies, ...
This paper considers a buffer-aided full-duplex (FD) relaying network assuming imperfect self-int... more This paper considers a buffer-aided full-duplex (FD) relaying network assuming imperfect self-interference (SI) cancellation. The residual SI level is modeled to be proportional to the relay transmit power. Moreover, for quality-of-service (QoS) provisioning, the end-to-end queue-length is statistically constrained in terms of maximum acceptable outage probability. We derive the optimal power allocation solution for the source and relay to maximize the constant supportable arrival rate μ to the source (i.e., the effective capacity) and study its properties. Illustrative examples are performed to compare the effective capacities of the proposed FD relaying scheme and other benchmark schemes under different settings and QoS constraints.
This paper develops Quality of Service (QoS) based routing and priority class assignment algorith... more This paper develops Quality of Service (QoS) based routing and priority class assignment algorithms using an end-to-end delay satisfaction balancing approach. Unlike the single-class delay satisfaction balancing optimization problem, the nonlinear multi-priority formulation is only convex ...
Springer briefs in electrical and computer engineering, 2017
Next-generation wireless systems are expected to support an ever increasing number of wireless co... more Next-generation wireless systems are expected to support an ever increasing number of wireless connections with better quality-of-service (QoS), e.g., higher data rate and smaller delay [1, 2]. As a result, energy consumption, as well as energy cost, and greenhouse gas emission are increased, which pose challenges in the design of wireless systems. One promising method to tackle this issue is energy harvesting (EH), where wireless nodes have the capability to harvest energy from the renewable sources (e.g., solar, and thermoelectric, etc.) of the surrounding environment, and store the harvested energy in batteries to carry out their functions. In this chapter, we explore power allocation problems for such EH systems to support delay-sensitive communications.
Springer briefs in electrical and computer engineering, 2017
In this chapter, we consider a point-to-point communications link over a fading channel with rand... more In this chapter, we consider a point-to-point communications link over a fading channel with randomly arriving data at the source buffer for transmission to the destination. For delay quality-of-service (QoS) requirement, (maximum) average delay constraint is imposed. Also, the source is assumed to have (maximum) average power constraint. To avoid constraint violation, it is assumed that only a portion of the arriving data can be buffered (or admitted). Note that the considered data buffer admission control is different from the common user (or stream) admission control. In the latter case, we admit a particular user (among many users) into the system while in the former, we admit data packets of an already admitted user (or stream) into the transmission buffer. Under such settings, this chapter studies the joint data admission control-power allocation (AC-PA) to maximize the throughput defined as the average admitted rate. In particular, we first analyze the structural properties of the optimal AC-PA policy with respect to fading channel, data arrival, and queue length states. We then propose an online AC-PA algorithm when the statistical knowledge of the system random channel fading, and data arrival processes is unknown.
REV Journal on Electronics and Communications, 2014
Neighbor area network (NAN), also known as smart meter communication network, is one of the most ... more Neighbor area network (NAN), also known as smart meter communication network, is one of the most important segments of smart grid communications network (SGCN). This paper studies the performance of greedy perimeter stateless routing (GPSR), a representative implementation of geographic-based routing class, in the NAN scenario and investigates the feasibility of this routing protocol in supporting SG applications. Specifically, packet transmission delay and reliability of GPSR in an IEEE 802.15.4-based wireless mesh NAN with practical system parameters are measured by simulations. The results show that, at the data rate required for conventional SG applications including smart metering, real-time pricing and demand response, the delay can always be maintained below 70 ms (in 95th-percentile perspective) while packet delivery ratio is higher than 90%. However, due to that fact that more advanced applications that require information exchange at higher rates and more stringent delays ...
CCECE 2003 - Canadian Conference on Electrical and Computer Engineering. Toward a Caring and Humane Technology (Cat. No.03CH37436), 2003
Abstract-The recent growth in Intemet trafic and services has made the provisioning of End-to-End... more Abstract-The recent growth in Intemet trafic and services has made the provisioning of End-to-End Qualiry of Service (QoS) in large-scale networkr a necessiw. Traffic Engineering (TE) emerges as an important constituent of QoS provisioning. This paper presents a ...
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