Radio resource allocation in third generation mobile communicationsystems

Code-division multiple access has been widely accepted as the major multiple access scheme in third-generation mobile communication systems. Wide-band CDMA and its hybrid associate time-division CDMA are key elements of the IMT2000 framework of standards. Since the beginning of the 1990s there has been enormous research activity in analysis of the soft (i.e., interference limited) capacity of these CDMA-based systems. Optimal usage of the soft capacity to provide, maintain, and guarantee QoS for different service classes is now becoming a very important issue. Therefore, interest in radio resource allocation has recently. This article presents an overview of RRA schemes (primarily for CDMA-based systems) that are flexible, support traffic services with various QoS requirements, minimize call/session blocking and dropping probabilities, and have acceptable radio resource utilization     

OFDM固定中继系统中单中继多源用户资源分配方案

通过基站的反馈信息,一个固定中继节点可以用一个OFDM符号同时帮助多个源用户转发信息,这样可以有效地利用带宽。因此,为了进一步提高系统容量,降低中断概率,先在中继节点间进行子载波调整,然后以获取信道容量最大为原则,提出了源用户和中继节点间子载波配对和功率分配的联合优化算法。仿真结果表明,相对于随机中继子载波选择算法以及平均功率分配算法,所提算法的中继系统容量有较大提升,同时中断概率有较为明显的下降。     

新一代国际互联网的发展趋向

简述近年通信业务量随着Internet广泛使用急剧上升。概述了利用波分复用系统可使光纤传输容量快速增长。说明了数字通信网必将充分利用分组交换，展望了电互联网进化为光互联网的美好前景。     

任务迁移的移动边缘计算系统中资源分配和任务卸载策略

针对在任务卸载时由于设备的移动而导致任务迁移这一问题,将任务卸载过程建模为马尔科夫决策过程,并通过优化资源分配和任务卸载策略,解决基于联合时延和能耗的损耗函数最小的优化问题。首先将问题转化为最小化损耗函数之和,并在决策前对每个任务的传输功率采用二分法进行优化,然后基于获得的传输功率提出一种QLBA（Q-learning Based Algorithm）来完成卸载决策。仿真结果证实所提方案优于传统算法。     

重视新一代信息技术加速TD-LTE产业化

"十二五"规划彰显新一代信息技术重要性 刚刚闭幕的十七届五中全会通过的关于制定国民经济和社会发展第十二个五年规划建议中,以科学发展为主题,以加快转变经济发展方式为主线,坚持把经济结构、战略性调整作为加快转变经济发展方式的主攻方向,坚持把科技进步和创新作为加快转变经济发展方式的重要支撑,我们要认真学习并将建议的精神贯穿到我们的各项实际工作中.     

用于移动Internet随机接入的一种新方式

介绍了移动通信网络中随机接入的概念，论述了移动Internet随机接入的特点，提出了基站调控的slotted-ALOHA随机接入方式，并从理论分析和计算机仿真两方面与现行的移动通信随机接入方式进行了对比，表明该方式能显著提高随机接入性能，使用代价微小，易于实际应用。     

移动IP 切换时资源分配动态策略生成机制研究

针对多媒体业务在切换后无法立即获得有保证服务的问题,提出一种移动IP切换时资源管理的动态策略模型,并着重设计模型中动态策略的生成机制。该机制根据移动节点相关预测信息自动生成动态策略,在切换前作准入控制和资源准备。当接入域资源不足时,采用“退却”算法,在保证业务可靠性前提下按优先级灵活调整各业务的资源占有量。分析和仿真表明,该机制能保证较高优先级业务的QoS,提高切换成功率,相对于传统方法更灵活。     

Resource allocation in broadband ISDNs

Broadband integrated services digital networks (BISDNs) have recently received significant attention among researchers in the field of telecommunications. These broadband telecommunication networks are being designed for handling, in their final form, a large variety of digital information, e.g., data, voice, video, facsimile, etc. Asynchronous transfer mode (ATM) has been recommended by the CCITT as a means of providing efficient and fast packet switched communication among BISDN users. It supports a large variety of services in a simple and unified fashion. An efficient and simple, yet effective, technique for resource allocation in broadband networks is presented. This technique was simulated for a network with three types of services and results are presented in terms of call blocking probabilities for several different cases.<>     

Resource allocation and hybrid prediction scheme for low-latencyvisual feedbacks to support tactile Internet multimodal perceptions

Predicting user states in future and rendering visual feedbacks accordingly can effectively reduce the visual experienced delay in the tactile Internet (TI). However, most works omit the fact that different parts in an image may have distinct prediction requirements, based on which different prediction models can be used in the predicting process, and then it can further improve predicting quality especially under resources-limited environment. In this paper, a hybrid prediction scheme is proposed for the visual feedbacks in a typical TI scenario with mixed visuo-haptic interactions, in which haptic traffic needs sufficient wireless resources to meet its stringent communication requirement, leaving less radio resources for the visual feedback. First, the minimum required number of radio resources for haptic traffic is derived based on the haptic communication requirements, and wireless resources are allocated to the haptic and visual traffics afterwards. Then, a grouping strategy is designed based on the deep neural network (DNN) to allocate different parts from an image feedback into two groups to use different prediction models, which jointly considers the prediction deviation thresholds, latency and reliability requirements, and the bit sizes of different image parts. Simulations show that, the hybrid prediction scheme can further reduce the visual experienced delay under haptic traffic requirements compared with existing strategies.     

A new bandwidth allocation mechanism for next generation wireless cellular networks

In this paper we design and study the performance of a Medium Access Control (MAC) scheme for the multiplexing and the integrated delivery of voice, mobile messaging, IP, gaming and H.264 videoconference traffic over a high-speed cellular TDMA channel with errors and capture. To the best of our knowledge, this is one of the first papers in the literature investigating the integration of actual H.264 video traces and gaming traffic with other types of traffic over wireless networks. Our results show that the proposed scheme achieves high throughput results while preserving the strict Quality of Service (QoS) requirements of each traffic type, and outperforms two efficient schemes previously proposed in the literature.     

移动互联网时代充值支付在新渠道快速上线的体系分析

随着网络的快速发展和手机功能的不断强大,互联网发生了用户习惯的大改变。为了更好地适应顾客消费习惯的改变,以服务赢得用户、跟随用户的步伐拓展渠道成为中国移动当前业务发展的新方向,秉持为客户提供最便利的服务的宗旨,开展建设互联网充值新渠道。文章以中国移动为例,介绍了其互联网时代充值支付在新渠道快速上线的体系,并结合当前形势进行简单的分析。     

OpenRAN: a new architecture for mobile wireless Internet radioaccess networks

Cellular telephony networks depend on an extensive wired network to provide access to the radio link. The wired network, called a radio access network, provides such functions as power control and, in CDMA networks, combination of soft handoff legs (also known as macrodiversity resolution) that require coordination between multiple radio base stations and multiple mobile terminals. Existing RAN architectures for cellular systems are based on a centralized radio network controller connected by point-to-point links with the radio base transceiver stations. The existing architecture is subject to a single point of failure if the RNC fails, and is difficult to expand because adding an RNC is expensive. Also, although a network operator may have multiple radio link protocols available, most RAN architectures treat each protocol separately and require a separate RAN control protocol for each. We describe a new architecture, the OpenRAN architecture, based on a distributed processing model with a routed IP network as the underlying transport fabric. OpenRAN was developed by the Mobile Wireless Internet Forum IP in the RAN working group. The OpenRAN architecture applies principles to the radio access network that have been successful in reducing cost and increasing reliability in data communications networks. The result is an architecture that can serve as the basis for an integrated next-generation cellular radio access network     

The mobile phone meets the Internet

Fifteen years ago mobile telephones were an exotic extravagance. Today, as cellular phones, they are often given away as freebies in support of marketing schemes and product promotions. Having become a mainstream voice communication medium, they are poised to take on new challenges, transmitting (fairly) high-speed data, video and multimedia traffic as well as voice signals to users on the move. The technology needed to tackle the challenges is known as third-generation cellular telephony. From this viewpoint, the early analog cell phones are labeled the first generation, and similar systems featuring digital radio technologies are labeled the second generation. These newer phones have appeared alongside of, and in some places have replaced, their analog forebears     

Radio resource allocation in fixed broadband wireless networks

We consider use of fixed broadband wireless networks to provide packet services for telecommuting and Internet access. Each cell is divided into multiple sectors, each of them served by a sector antenna colocated with the base station (BS), and user terminals also use directional antennas mounted on the rooftops of homes or small offices and pointed to their respective BS antennas. To support a target data rate of 10 Mb/s, a bandwidth of several MHz is required. Since radio spectrum is expensive, the bandwidth needs to be reused very aggressively. Thus, efficient strategies for frequency reuse and managing cochannel interference are critically important. We propose several algorithms for dynamic radio-resource allocation in the fixed wireless networks. In particular, a method to be referred to as the staggered resource allocation (SRA) method uses a distributed scheduling algorithm to avoid major sources of interference while allowing concurrent packet transmission and meeting signal-to-interference objectives. The performance of the method is studied by analytic approximations and detailed simulation. Our results show that the combination of directional antennas plus the SRA method is highly effective in controlling cochannel interference. For reasonable system parameters, the SRA method delivers a throughput in excess of 30% per sector while permitting a given frequency band to be reused in every sector of every cell. It also provides satisfactory probability of successful packet transmission. In addition, a simple control mechanism can be applied in the method to improve performance for harsh radio environments     

一种新型Ad Hoc网络的分布式RSA密钥生成机制

本文在分析现有几种基于分布式PKI/CA体制的安全解决方案中,如何生成和分发CA密钥存在问题的基础上,提出了一种应用于AdHoc网络的新型密钥生成机制─基于门限RSA密码体制的分布式CA密钥共享生成机制,显著提高了系统的安全性和鲁棒性。     

Cellular mobile — the generation game

Cellular mobile is at an important crossroads — with the industry still in the process of attempting a transition from the dominant second generation services of voice and messaging, to data-based services such as music download and gaming. Third generation technology has rolled out slowly in Europe and has yet to make much of an impact on the market. Against this backdrop, the cellular industry is now moving towards defining fourth generation mobile for introduction in 2012–2015. The emergence of new, non-cellular systems, such as WiMAX and WLAN are confusing the timeline and evolution of cellular systems with a heated debate about what constitutes a ‘4G system’. In addition, some people view convergence as the next generation of mobile with less emphasis on raw connection speed and more on access to the same services over a range of access technologies and devices. In this paper we critically examine these and other views of fourth generation mobile (4G) and identify the key technological, standards-related and commercial issues that will drive the evolution of 4G over the next few years.     

Resource allocation and connection admission control in satellitenetworks

This work focuses on resource allocation and connection admission control (CAC) issues in broadband satellite networks. Broadband services can now be provided by satellite systems operating in the Ka band, due to the large bandwidth available at such frequencies. In this context, we propose a resource allocation algorithm which integrates three classes of services at the MAC layer: constant bit rate (CBR), bursty data, and best effort services. The double movable boundary strategy (DMBS) is proposed to establish a resource-sharing policy among these service classes over the satellite uplink channel. The DMBS is a dynamically controlled boundary policy which adapts the allocation decision to the variable network loading conditions. Connection-oriented and connectionless services can be supported by the system. The CAC and slot allocation decisions are taken at the beginning of each control period after monitoring the filling level of traffic request queues. A threshold level for the bursty data request queue is defined to regulate the CAC process. The impact of the queue threshold value on the performance of the DMBS allocation policy is particularly evaluated in this study. A dynamic variation of this value is also proposed to enhance the system response to interactive applications. We present a brief analytical formulation for the DMBS model, together with simulation study details and performance evaluation results. The obtained results indicate a good efficiency, in terms of overall channel throughput and CBR blocking probability, for both fixed and dynamic data queue threshold approaches. The dynamic approach, however, outperforms the fixed one in terms of overall encountered bursty data delay     

智能铁路新一代移动通信关键技术探索与展望

移动通信技术的进步驱动着各行各业的产业变革。铁路现有移动通信系统历经几十年的发展,其承载能力越来越难以满足高速增长的现代铁路网建设步伐和智能化发展需求。基于智能铁路应用对移动通信带宽、时延、覆盖等需求和新一代移动通信面临的挑战,开展新一代通信频谱技术、信道编码技术及多功能综合射频技术等新一代移动通信关键技术研究,构建以“车-地、车-车、车-人”信息无缝协同交互为目标的“空天车地一体化”网络,研究并展望通信-导航一体化、通信-计算-存储一体化在智能铁路中的场景应用,提升铁路移动通信服务能力和效率,赋能我国铁路智能化发展。     

移动因特网中的视频译码系统

讨论了在移动因特网环境下的视频传输问题，介绍了一种能够根据传输环境、终端能力、客户需求动态改变参数的视频译码系统，描述了系统的结构和控制过程。