基于传输速率自适应的动态带宽分配算法

提出一种基于传输速率自适应的动态带宽分配算法,为异构无线网络中的多业务提供服务质量保证。根据所提的传输速率优先级决策模型,在传输速率QoS需求和异构网络容量约束的条件下,通过动态调整不同网络中各个移动终端所支持业务的传输速率来得到最优带宽重分配矩阵,以最大化整个异构网络的效用函数;将自适应带宽重分配问题描述为一个优化问题,采用动态优化的迭代算法自适应调节用户传输速率来进一步最大化该效用函数。理论分析和数值仿真结果表明,所提算法在给定传输速率且满足QoS需求的基础上,能够最大化网络的效用函数并减小新呼叫的阻塞概率。     

基于用户个性化服务质量的蜂窝车联网与车载自组织网异构车联网资源分配方法

蜂窝车联网(C-V2X)与车载自组织网络(VANET)的异构融合能够有效提高网络容量。然而,不同网络在非授权频段上共存而引起的信道冲突会导致系统吞吐量降低和用户接入时延增大,无法满足车联网用户对服务质量(QoS)的需求。针对该问题,该文提出一种基于用户个性化QoS需求的时频资源分配方法。首先,分别对C-V2X 和 VANET 的吞吐量和时延进行建模分析,刻画用户数据传输时间配置与吞吐量和时延的数学关系;然后,基于上述模型构建吞吐量-时延联合优化函数,根据用户的个性化QoS需求实现异构网络中吞吐量和时延的优化;最后,提出一种基于改进多目标粒子群优化的时延-吞吐量联合优化算法(DT-JOA)进行求解。仿真结果表明,该文所提网络资源分配算法可以有效地保证用户的个性化QoS需求,提升异构网络综合性能。     

基于业务认知的多用户带宽分配方法

无线局域网的MAC协议难以兼顾多用户差别的业务需求和网络吞吐量的有效性。建立具有超帧结构的带宽分配模型和具有惩罚函数的优化目标,计算满足单用户QoS需求的最小带宽,进而提出基于业务认知的多用户带宽分配算法(TCBAA)。该算法优先满足用户QoS要求,其次最大化系统的吞吐量。理论和仿真实验显示:相比于固定分配机制和最大吞吐量分配机制,TCBAA能够在有限带宽下满足更多用户的QoS需求。     

基于用户个性化服务质量的蜂窝车联网与车载自组织网异构车联网资源分配方法

蜂窝车联网(C-V2X)与车载自组织网络(VANET)的异构融合能够有效提高网络容量.然而,不同网络在非授权频段上共存而引起的信道冲突会导致系统吞吐量降低和用户接入时延增大,无法满足车联网用户对服务质量(QoS)的需求.针对该问题,该文提出一种基于用户个性化QoS需求的时频资源分配方法.首先,分别对C-V2X 和 VANET 的吞吐量和时延进行建模分析,刻画用户数据传输时间配置与吞吐量和时延的数学关系;然后,基于上述模型构建吞吐量-时延联合优化函数,根据用户的个性化QoS需求实现异构网络中吞吐量和时延的优化;最后,提出一种基于改进多目标粒子群优化的时延-吞吐量联合优化算法(DT-JOA)进行求解.仿真结果表明,该文所提网络资源分配算法可以有效地保证用户的个性化QoS需求,提升异构网络综合性能.     

VLC-WiFi异构网络QoS感知的跨层动态资源分配

VLC-WiFi异构网络已经成为广受欢迎的短距离无线通信方式之一。然而,有限的频谱资源导致VLC-WiFi异构网络容量难以满足井喷式增长的用户数据带宽需求。该文结合物理层的动态链路传输性能以及媒体访问控制层的队列缓冲延迟性能,定义链路传输性能和链路服务质量(QoS)感知等级评估公式,根据用户数据包QoS需求,设计QoS感知的跨层动态资源分配(QoS-CLDRA)方法,并引入非正交多址接入的用户匹配与功率分配策略,进一步提升系统的吞吐量。仿真结果表明:所提方法能够有效提升系统吞吐量和降低缓冲队列长度。     

异构无线网络多用户多业务接入中多目标优化控制方法研究

针对多异构网络重叠覆盖、多用户多业务共存环境下,用户最大化传输速率易致网络负载不均衡的问题,提出一种基于非支配排序遗传算法的业务接入控制方法。该方法首先以传输速率最大化及网络负载最均衡为目标,以带宽资源受限为约束,构建了传输速率最大化及网络负载最均衡的双目标优化模型;然后基于多目标优化方法非支配排序遗传算法(Non-dominated Sorting Genetic AlgorithmⅡ,NSGA-Ⅱ)求解该业务接入控制问题。仿真结果表明,所提算法兼顾了用户的传输速率需求及网络间的负载均衡,取得较好的效果。     

基于动态多目标决策的异构环境QoS策略

在未来的移动通信网络中,多种异构的接入网络并存将成为普遍的情况,因此需要根据接入网络与终端当前状况及当前业务需求,动态地为用户提供最佳接入网络选择。提出了一种基于动态信息多目标决策的异构网络选择算法,通过综合考虑以上信息,保证了用户的QoS需求。     

H-CRAN网络下联合拥塞控制和资源分配的网络切片动态资源调度策略

针对异构云无线接入网络(H-CRAN)网络下基于网络切片的在线无线资源动态优化问题,该文通过综合考虑业务接入控制、拥塞控制、资源分配和复用,建立一个以最大化网络平均和吞吐量为目标,受限于基站(BS)发射功率、系统稳定性、不同切片的服务质量(QoS)需求和资源分配等约束的随机优化模型,并进而提出了一种联合拥塞控制和资源分配的网络切片动态资源调度算法。该算法会在每个资源调度时隙内动态地为性能需求各异的网络切片中的用户分配资源。仿真结果表明,该文算法能在满足各切片用户QoS需求和维持网络稳定的基础上,提升网络整体吞吐量,并且还可通过调整控制参量的取值实现时延和吞吐量间的动态平衡。     

一种WDM-EPON的DBA算法及其改进

介绍了一种WDM-EPON的DBA算法并对其进行改进,改进的算法能根据ONU端不同的业务类型情况对波长和带宽进行分配,以支持多业务接入的QoS,从而使整个网络带宽的得到更公平有效地分配,最后用OPNET进行仿真,结果表明改进的算法能为不同等级的业务流提供相应的带宽,时延等QoS保证.     

基于模糊层次—熵权法的自适应垂直切换算法

针对当前异构网络中,采用多决策属性的垂直切换算法难以动态调整网络属性的权重值,从而无法满足用户服务质量(QoS)的需求问题,文章以接入最优的异构无线网络和保障用户QoS为目标,提出基于模糊层次—熵权法的自适应垂直切换算法.首先,根据用户对网络属性的不同要求,采用主观模糊层次赋权与客观熵权法结合的方式构建网络属性优化模型...     

Cross‐layer bandwidth and power allocation for a two‐hop link in wireless mesh network

In this paper, a cross‐layer analytical framework is proposed to analyze the throughput and packet delay of a two‐hop wireless link in wireless mesh network (WMN). It considers the adaptive modulation and coding (AMC) process in physical layer and the traffic queuing process in upper layers, taking into account the traffic distribution changes at the output node of each link due to the AMC process therein. Firstly, we model the wireless fading channel and the corresponding AMC process as a finite state Markov chain (FSMC) serving system. Then, a method is proposed to calculate the steady‐state output traffic of each node. Based on this, we derive a modified queuing FSMC model for the relay to gateway link, which consists of a relayed non‐Poisson traffic and an originated Poisson traffic, thus to evaluate the throughput at the mesh gateway. This analytical framework is verified by numerical simulations, and is easy to extend to multi‐hop links. Furthermore, based on the above proposed cross‐layer framework, we consider the problem of optimal power and bandwidth allocation for QoS‐guaranteed services in a two‐hop wireless link, where the total power and bandwidth resources are both sum‐constrained. Secondly, the practical optimal power allocation algorithm and optimal bandwidth allocation algorithm are presented separately. Then, the problem of joint power and bandwidth allocation is analyzed and an iterative algorithm is proposed to solve the problem in a simple way. Finally, numerical simulations are given to evaluate their performances. Copyright © 2008 John Wiley & Sons, Ltd.     

Resource allocation algorithm for LTE networks using fuzzy based adaptive priority and effective bandwidth estimation

In this paper, we propose a scheme to allocate resource blocks for the Long Term Evolution (LTE) downlink based on the estimation of the effective bandwidths of traffic flows, where users’ priorities are adaptively computed using fuzzy logic. The effective bandwidth of each user traffic flow that is estimated through the parameters of the adaptive β-Multifractal Wavelet Mode modeling, is used to attain their quality of service (QoS) parameters. The proposed allocation scheme aims to guarantee the QoS parameters of users respecting the constraints of modulation and code schemes (modulation and coding scheme) of the LTE downlink transmission. The proposed algorithm considers the average channel quality and the adaptive estimation of effective bandwidth to decide about the scheduling of available radio resources. The efficiency of the proposed scheme is verified through simulations and compared to other algorithms in the literature in terms of parameters such as: system throughput, required data rate not provided, fairness index, data loss rate and network delay.     

An optimal solution to resource allocation among soft QoS traffic in wireless network

Optimization theory and nonlinear programming method have successfully been applied into wire‐lined networks (e.g., the Internet) in developing efficient resource allocation and congestion control schemes. The resource (e.g., bandwidth) allocation in a communication network has been modeled into an optimization problem: the objective is to maximize the source aggregate utility subject to the network resource constraint. However, for wireless networks, how to allocate the resource among the soft quality of service (QoS) traffic remains an important design challenge. Mathematically, the most difficult comes from the non‐concave utility function of soft QoS traffic in the network utility maximization (NUM) problem. Previous result on this problem has only been able to find its sub‐optimal solution. Facing this challenge, this paper establishes some key theorems to find the optimal solution and then present a complete algorithm called utility‐based allocation for soft QoS to obtain the desired optimal solution. The proposed theorems and algorithm act as designing guidelines for resource allocation of soft QoS traffic in a wireless network, which take into account the total available resource of network, the users’ traffic characteristics, and the users’ channel qualities. By numerical examples, we illustrate the explicit solution procedures.Copyright © 2013 John Wiley & Sons, Ltd.     

Cross-layer resource allocation for QoS guarantee with finite queue constraint in multirate OFDMA wireless networks

Efficient radio resource allocation is essential to provide quality of service （QoS） for wireless networks. In this article, a cross-layer resource allocation scheme is presented with the objective of maximizing system throughput, while providing guaranteed QoS for users. With the assumption of a finite queue for arrival packets, the proposed scheme dynamically a/locates radio resources based on user＇s channel characteristic and QoS metrics derived from a queuing model, which considers a packet arrival process modeled by discrete Markov modulated Poisson process （dMMPP）, and a multirate transmission scheme achieved through adaptive modulation. The cross-layer resource allocation scheme operates over two steps. Specifically, the amount of bandwidth allocated to each user is first derived from a queuing analytical model, and then the algorithm finds the best subcarrier assignment for users. Simulation results show that the proposed scheme maximizes the system throughput while guaranteeing QoS for users.     

基于双连接和回传带宽配置的系统吞吐量效用和最大化算法

针对双连接可行的异构无线网络中关于用户关联和回传带宽配置的联合优化问题,构建了一个新的网络吞吐量效用和最大化框架。将该联合优化问题建模为一个非凸的混合整数分式优化问题。为了便于求解,首先将原建模问题进行去分式化转换,然后针对转换后依旧非凸的混合整数非线性优化问题,将其分解为两个优化子问题分别求解。通过固定用户关联变量,得到了最优的回传带宽配置机制;通过固定回传带宽配置因子变量,提出一个有效的迭代算法求解双连接可行的用户关联子问题。相比固定的回传带宽配置机制,所提算法可以获得最优的回传单位带宽配置因子值,同时拥有最优的系统吞吐量和系统吞吐量效用和性能。     

A Noncooperative Game-Theoretic Framework for Radio Resource Management in 4G Heterogeneous Wireless Access Networks

Fourth generation (4G) wireless networks will provide high-bandwidth connectivity with quality-of-service (QoS) support to mobile users in a seamless manner. In such a scenario, a mobile user will be able to connect to different wireless access networks such as a wireless metropolitan area network (WMAN), a cellular network, and a wireless local area network (WLAN) simultaneously. We present a game-theoretic framework for radio resource management (that is, bandwidth allocation and admission control) in such a heterogeneous wireless access environment. First, a noncooperative game is used to obtain the bandwidth allocations to a service area from the different access networks available in that service area (on a long-term basis). The Nash equilibrium for this game gives the optimal allocation which maximizes the utilities of all the connections in the network (that is, in all of the service areas). Second, based on the obtained bandwidth allocation, to prioritize vertical and horizontal handoff connections over new connections, a bargaining game is formulated to obtain the capacity reservation thresholds so that the connection-level QoS requirements can be satisfied for the different types of connections (on a long-term basis). Third, we formulate a noncooperative game to obtain the amount of bandwidth allocated to an arriving connection (in a service area) by the different access networks (on a short-term basis). Based on the allocated bandwidth and the capacity reservation thresholds, an admission control is used to limit the number of ongoing connections so that the QoS performances are maintained at the target level for the different types of connections.     

Dynamic-Grouping bandwidth reservation scheme for multimedia wireless networks

In wireless networks carrying multimedia traffic (voice, video, data, and image), it becomes necessary to provide a quality-of-service(QoS) guarantee for multimedia traffic connections supported by the network. In order to provide mobile hosts with high QoS in the next-generation wireless networks, efficient and better bandwidth reservation schemes must be designed. This paper presents a novel dynamic-grouping bandwidth reservation scheme as a solution to support QoS guarantees in the next-generation wireless networks. The proposed scheme is based on the probabilistic resource estimation to provide QoS guarantees for multimedia traffic in wireless cellular networks. We establish several reservation time sections, called groups, according to the mobility information of mobile hosts of each base station. The amount of reserved bandwidth for each base station is dynamically adjusted for each reservation group. We use the dynamic-grouping bandwidth reservation scheme to reduce the connection blocking rate and connection dropping rate, while increasing the bandwidth utilization. The simulation results show that the dynamic-grouping bandwidth reservation scheme provides less connection-blocking rate and less connection-dropping rate and achieves high bandwidth utilization.     

一种具有弹性服务质量要求的多业务最优接纳控制策略

随着无线网络所支持的业务种类的增加和具有弹性服务质量要求的业务的大量出现，与服务质量保证密切相关的呼叫接纳控制问题成了近年来无线网络研究的热点之一。本文研究了基于准马尔可夫决策过程方法的多业务最优呼叫接纳控制问题。根据业务的特点，首先引入了带宽分配满意度函数和收益率函数，在此基础上，提出了基于带宽分配满意度的最优带宽分配算法和基于准马尔可夫决策过程方法的最优呼叫接纳控制策略。计算结果表明，本文方案能够在对各类业务的呼叫阻塞率进行适当权衡的前提下，进一步提高网络的期望收益率和期望带宽利用率，同时满足了各类业务的最低服务质量要求。     

Multiple access control with intelligent bandwidth allocation forwireless ATM networks

Two major challenges pertaining to wireless asynchronous transfer mode (ATM) networks are the design of multiple access control (MAC), and dynamic bandwidth allocation. While the former draws more attention, the latter has been considered nontrivial and remains mostly unresolved. We propose a new intelligent multiple access control system (IMACS) which includes a versatile MAC scheme augmented with dynamic bandwidth allocation, for wireless ATM networks. IMACS supports four types of traffic-CBR, VBR, ABR, and signaling control (SCR). It aims to efficiently satisfy their diverse quality-of-service (QoS) requirements while retaining maximal network throughput. IMACS is composed of three components: multiple access controller (MACER), traffic estimator/predictor (TEP), and intelligent bandwidth allocator (IBA). MACER employs a hybrid-mode TDMA scheme, in which its contention access is based on a new dynamic-tree-splitting (DTS) collision resolution algorithm parameterized by an optimal splitting depth (SD). TEP performs periodic estimation and on-line prediction of ABR self-similar traffic characteristics based on wavelet analysis and a neural-fuzzy technique. IBA is responsible for static bandwidth allocation for CBR/VBR traffic following a closed-form formula. In cooperation with TEP, IBA governs dynamic bandwidth allocation for ABR/SCR traffic through determining the optimal SD. The optimal SDs under various traffic conditions are postulated via experimental results, and then off-line constructed using a back propagation neural network (BPNN), being used on-line by IBA. Consequently, with dynamic bandwidth allocation, IMACS offers various QoS guarantees and maximizes network throughput irrelevant to traffic variation