战术异构网络互联端到端QoS研究

战术异构通信网络的融合,需要更完善的端到端服务质量（Quality of Service,QoS）体系。在研究和分析战术异构通信网特点后,分析总结出战术异构通信网络端到端QoS研究内容,并参考下一代网络QoS框架结构,提出了基于策略的QoS架构模型。最后阐述了所涉及的关键技术,用于解决在战术异构通信网中不同业务在跨网络传输时端到端QoS保证,合理利用无线网络资源,有效提高数据传输性能等问题。     

支持应急业务的公共LTE与多跳WiFi融合网络的资源优化

异构融合网络可为移动用户提供无缝的网络接入和QoS保证方面,融合网络成为当前研究的热点。但是很少文献根据异构网络的类型,从全网角度去考虑网络的整体性能。因此,多因素、全网优化显得尤为重要。针对LTE和无线多跳WiFi组成的异构网络特点,考虑普通业务和应急业务QoS保证,终端发射功率、异构网络整体容量提升和负载均衡进行资源调度优化,提高网络的利用效率。通过MATLAB仿真表明,该资源优化方法能有效地提供网络性能,相比较贪婪算法有更好的公平性。     

室内可见光通信异构融合系统研究进展

为了提高可见光通信系统性能,将可见光通信技术与其它通信技术异构融合,能使各类技术取长补短,增强通信系统容量,提高资源利用率。介绍了可见光通信分别与电力线通信（PLC）、Wi Fi、以太网、长期演进（LTE）网络、第五代/第六代移动通信技术（5G/6G）融合的方法及发展现状,对可见光通信异构融合系统的未来发展做了展望。     

IMS体系结构中的QoS问题探讨

完整的服务质量QoS解决方案是通信网络融合中的重要课题，引入基于IP多媒体子系统（IMS）框架的、具有QoS保证的资源控制架构是解决融合网络QoS问题的重要方法。在介绍基于综合服务与区分服务相结合的IMSQoS服务模型的基础上，详细讨论IMS网络中的QoS控制结构、资源控制和QoS授权等问题。     

融合网络的QoS问题探讨

通信网络的融合需要更完善的服务质量（QoS）体系。引入基于IP多媒体子系统（IMS）框架的QoS资源控制架构是解决融合网络QoS问题的方法。基于IMS框架的QoS控制架构将业务、QoS保证、资源控制和计费结合起来，是融合网络，特别是当前固网运营商急需的体系架构，能解决固网运营商当前运营过程中面临的问题，使其可以开展更多有QoS保证的多媒体业务，如3D游戏等，有助于运营商从通信带宽提供服务商向通信业务运营商转型。     

双层卫星网络QoS路由算法研究

具有星际链路的双层通信星座网络可为全球提供宽带实时多媒体通信服务,路由算法设计是其中关键技术之一。本文详细介绍了由低轨卫星与中轨卫星构成的空间信息通信网双层星座系统体系结构,提出了一种新的具有QoS保证的双层卫星网络路由算法。仿真结果表明提出的路由算法可以满足系统的QoS业务要求的延迟、丢包率与抖动等指标。     

协同异构蜂窝层叠网络基础理论与关键技术

从基础理论和关键技术两方面的研究进展与相关成果介绍首届国家重点基础研究发展计划("973"计划)青年科学家专题项目——协同异构蜂窝层叠网络基础理论与关键技术。其中,基础理论包括协同异构蜂窝层叠网络的体系架构、信道建模、网络容量域、连接性等问题;关键技术包括协同异构蜂窝层叠网络的干扰管理、资源分配、空白频谱检测与利用等。研究表明,协同异构蜂窝层叠网络下的D2D(device-to-device)通信由于其具有能够进一步增大频谱利用效率、提升系统容量等优点,将发展成为下一代蜂窝网络支持的关键技术。     

4G系统中的QoS保证技术研究

4G系统将是一个在IP的基础上融合的、具有多种异构性的网络。首先分析了4G系统的基本场景,并总结了在4G系统中提供QoS保证所面临的主要问题,然后给出了一个基本的QoS体系结构,在此基础之上进一步说明了支持这一体系结构的若干关键技术。     

下一代异构IP网络的关键技术

异构无线网络融合是移动通信系统发展的重要趋势,即融合的网络将统一于全IP。不同网络的实现技术、传输机理、组织方式、控制机制存在巨大差异,这对异构网络中诸如移动性管理、联合无线资源管理、端到端的QoS保证等关键问题提出了极大的挑战。文章就异构网络的关键技术发展进行了分析和讨论。     

下一代异构IP网络的关键技术

异构无线网络融合是移动通信系统发展的重要趋势，即融合的网络将统一于全IP。不同网络的实现技术、传输机理、组织方式、控制机制存在巨大差异，这对异构网络中诸如移动性管理、联合无线资源管理、端到端的QoS保证等关键问题提出了极大的挑战。文章就异构网络的关键技术发展进行了分析和讨论。     

Study on QoS and Communications Capacity in Heterogeneous Network Convergence

To provide any subscriber from anywhere at anytime with services that have both secured Quality of Service(QoS) and simultaneous expansion of network coverage and communications capacity is a key problem that has to be considered and solved in heterogeneous network convergence.Key technologies for a secured QoS and communications capacity analysis under heterogeneous environment are important subjects for research.Key technologies for a secured QoS are mainly on radio resource management algorithms covering Call Admission Control(CAC) algorithm,vertical handover algorithm,heterogeneous resource allocation algorithm and network selection algorithm.The applications of a novel multi-hop in heterogeneous convergence system serve the purposes of network coverage expansion,transmission power reduction,system communication capacity and throughput increase.     

An enhanced radio resource management based MIH policies in heterogeneous wireless networks

The require of omnipresent wireless access and high data rate services are expected to increase extensively in the near future. In this context, heterogeneous networks, which are a mixture of different wireless technologies (LTE-advanced, LTE-advanced Pro, C-IoT (Cellular Internet of Thing), 5G WiFi, etc) are invited to enable important capabilities, such as high data rates, low latencies and efficient resource utilization in order to provide dedicated capacity to offices, homes, and urban hotspots. Mixing these technologies in the same system, with their complementary characteristics, to afford a complete coverage to users can cause various challenges such as seamless handover, resource management and call admission control. This article proposes a general radio resource management framework which can be supported by future network architectures. A combined call admission control, resource reservation algorithm and bandwidth adaptation based IEEE 802.21 MIH standard approach for heterogeneous wireless network is detailed in this framework. Our aims are to guarantee quality of service (QoS) requirements of all accepted calls, reduce new call blocking probability and handover call dropping probability, and maintain efficient resource utilization. Performance analysis shows that our proposed approach best guarantees QoS requirements.     

Energy‐efficient resource allocation for lifetime maximization in M2M networks

Machine‐to‐machine (M2M) communications is one of the major enabling technologies for the realization of the Internet of Things (IoT). Most machine‐type communication devices (MTCDs) are battery powered, and the battery lifetime of these devices significantly affects the overall performance of the network and the quality of service (QoS) of the M2M applications. This paper proposes a lifetime‐aware resource allocation algorithm as a convex optimization problem for M2M communications in the uplink of a single carrier frequency division multiple access (SC‐FDMA)‐based heterogeneous network. A K‐means clustering is introduced to reduce energy consumption in the network and mitigate interference from MTCDs in neighbouring clusters. The maximum number of clusters is determined using the elbow method. The lifetime maximization problem is formulated as a joint power and resource block maximization problem, which is then solved using Lagrangian dual method. Finally, numerical simulations in MATLAB are performed to evaluate the performance of the proposed algorithm, and the results are compared to existing heuristic algorithm and inbuilt MATLAB optimal algorithm. The simulation results show that the proposed algorithm outperforms the heuristic algorithm and closely model the optimal algorithm with an acceptable level of complexity. The proposed algorithm offers significant improvements in the energy efficiency and network lifetime, as well as a faster convergence and lower computational complexity.     

Joint admission control algorithm based on load transfer in heterogeneous networks

A load-transfer-based joint admission control (LJAC) algorithm in heterogeneous networks was proposed.The access requirements of users were admitted based on load balancing,the dynamic load transfer of traffics in the overlapping coverage areas of heterogeneous networks were introduced,and the influence of such factors as the layout of heterogeneous networks and the vertical handoff was considered in the algorithm.The integrated system of heterogeneous networks was modeled as a multidimensional Markov chain,the steady-state probabilities were obtained and the quality of service (QoS) performance metrics were derived.Based on the Poisson point process theory,the upper bound of capacity of the heterogeneous networks satisfying QoS limitations was obtained.The admission control parameters of the integrated system of heterogeneous networks were optimized in order to maximize the resource utilization rate as well as guaranteeing the QoS of users.The simulation results demonstrate lower traffic blocking probability,lower failure probability of vertical handoff requirements,and larger system capacity gain can be achieved by using the proposed LJAC algorithm.     

An Access Selection Functional Architecture for Heterogeneous Multi-Mode Terminals

The convergence of heterogeneous wireless networks is an inevitable trend in broadband wireless communications development. In heterogeneous networks convergence environment, each wireless network can provide ubiquitous, best Quality of Service (QoS) services. The challenge lies in the design of the management system and access selection architecture for heterogeneous multi-mode terminals. A type of management architecture for heterogeneous multi-mode terminal via effective interaction with all protocol layers is adaptable for multi-access standards and technical requirements to achieve seamless access and mobility for multi-mode heterogeneous terminals. As the core subject for research, access selection functional architecture mainly consists of three modules, namely access adaptation, mobility management, and user preference.     

异构网络融合环境下基于加权二分图的网络选择算法

摘要：在异构网络融合场景中,为了合理利用异构网络资源,提出了一种基于加权二分图的网络选择算法。将网络选择过程映射为寻找最优加权二分图的过程,用户和网络双方的需求经数学建模后进行供需最优匹配,供需匹配有二次选择机会以平衡网络负载。与其他算法相比,提出的算法可以为不同QoS业务提供满足需求的匹配结果,并且能够动态调整网络负载,实现异构网络融合场景中用户需求和网络资源的合理匹配。     

A Generic Analytical Modelling Approach for Performance Evaluation of the Handover Schemes in Heterogeneous Environments

In recent years, there has been an increased interest in the integration of different technologies in heterogeneous environments. Modelling heterogeneous systems is a complex task and handover schemes should consider issues such as network coverage, mobility, and Quality of Service (QoS). Analytical models are useful to deal with this complexity. This paper presents a generic framework to model handover in heterogeneous environments for performance evaluation of different handover schemes. The model developed considers mobility of the users, coverage radius of the networks as well as decision making probabilities about handover between the two networks. The interaction between cellular mobile technologies is considered and handover between a WLAN and a cellular system is analysed using the proposed model. Two stage open networks can be used to model this kind of integrated systems. The cellular mobile technologies are modelled as a multi-channel queuing system while the WLAN is depicted as a single channel queuing system, both with finite buffers. The exact spectral expansion method is employed to solve the models. Simulation is also employed for the proposed systems and used for validation of the accuracy of the proposed models. Numerical results are presented for mean queue length and blocking probabilities for each system. The results of this study show that QoS measures of such systems can be evaluated efficiently and accurately, using the proposed analytical model and its solution. In addition, it can be used as a framework in heterogeneous environments and can also be adapted to various types of networks in interaction.     

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.     

A Novel Scheduling Algorithm for Low and High Mobility Users in Multi-hop WiMAX Network

QoS provisioning and high capacity for high mobility users are considered as the distresses of broadband wireless communications (BWC) and specifically the key technology of WiMAX. Hence, the scheduling and resource allocation algorithms play the main role in this regard. In the research conducted on scheduling algorithms in WiMAX network, two principal methods of AMC and PUSC are used. The high capacity in AMC mode algorithms is achieved by considering the low speed users. Conversely, in PUSC mode algorithms, speed does not affect the network performances; however, the capacity is low. To date, the importance of presenting QoS and maintaining the network capacity for the users with different speeds has not been acknowledged yet. This paper presents novel scheduling algorithms and also new frame partitioning scheme which are proper for the users with different mobility speeds. The new algorithm uses two modes of AMC and PUSC simultaneously to maintain the high capacity of the network. QoS is also provided. The simulation results reveal that our algorithm increases capacity while it presents low packet delay and packet loss rate in the presence of both high and low mobility speed users.