基于ATM技术的无线PCS网

文中介绍了无线ATM的网络结构、协议参考模型和PCS支持的固定ATM网的信令协议,它是对目前的ATM和PCS规范的最小修改。     

无线ATM及其移动性管理

文章对无线ATM的一些关键技术进行了分析,提出了在ATM网络中支持终端移动性的网络体系结构—移动ATM(Mobile ATM),并重点讨论了位置管理和切换管理问题。     

一种智能无线充电系统设计

针对目前市场上存在的大部分无线充电系统充电效率低、充电电量可控性差等问题,文章设计了一种全新的智能无线充电系统。该系统在电池模块中嵌入电量采集模块、低功耗主控芯片和2.4G通信模块,充电模块中嵌入同样的主控和通信模块。充电模块可通过2.4G无线通信接收电池的实时电压和充电电流等信息,根据内置的智能算法,通过振幅调制载波功率限制,实现自适应动态输出。实验表明,在有效距离内,该系统具有较高的充电效率,具体充电情况可根据电池实时电量信息进行智能控制,有效地预防了电池过充和过放等问题。该智能无线充电系统具有低功耗、转换效率高、能够对充放电智能管理等特点,可广泛应用于智能家居、智能医疗、智能穿戴等领域,具有良好的社会价值和经济价值。     

Mobility information for resource management in wireless ATM networks

User mobility poses a significant technical challenge to network resource management in wireless ATM (Asynchronous Transfer Mode) networks. In order to guarantee quality of service (QoS) to mobile users and to achieve a high efficiency in network resource management, the information of mobile users' handoff at a future moment is essential for statistical multiplexing. This paper develops a novel fuzzy logic inference system to estimate the user mobility information for a wireless ATM network which uses a direct sequence code division multiple access (DS/CDMA) protocol. The estimation is based on measured pilot signal strengths from a number of the nearest base stations by the mobile user. Numerical results are presented to demonstrate the performance of the proposed technique under various path losses and channel shadowing conditions. The proposed technique can achieve simplicity, accuracy and low cost.     

Mobility management for m-commerce requests in wireless cellular networks

Increasing number of sophisticated services provided by the current wireless communication systems have caused a significant transition from E-commerce to M-commerce. Enterprises have provided considerable new opportunities to promote their businesses accessible from small mobile devices such as personal digital assistant (PDA) or mobiles phones. These facilities are envisioned as the most convenient way of using M-commerce. Using such services from mobile phones or PDAs equipped with GSM/GPRS involve effective mobility management mechanisms in cellular networks—a popular architecture for wireless networks. Success of such systems will largely depend on the reliable connection for the roaming users. Consequently, Quality of Service (QoS) provision is one of the most challenging issues in the heterogeneous wireless network-based m-commerce systems. Such m-commerce systems enable users to roam between different wireless networks operators and geographical areas while providing interactive broadband services and seamless connectivity. This paper presents an analytical framework to model scarce channels in any cell for maximizing channel utilization and efficient handling of handover requests. Typical numerical experiments are presented to validate the analytical solution against simulation to study the effect of bursty traffic upon the performance of the cell in any cellular networks.     

无线工业控制网络中的时间同步研究

针对无线工业控制网络WICN的特点,分析RBS和TPSN时间同步算法的不足。利用基于令牌的MAC协议,提出一种适用于无线工业控制网的时间同步算法WICNTS,该算法采用MAC层记录时戳的方式进行成对同步。然后给出了模型的建立过程,并用离散事件仿真平台OMNeT++对该协议进行仿真实验,仿真结果表明该算法能满足WICN网络的时间同步要求。     

ATM网络VP层的控制技术研究

文中介绍了ATM网络VP层控制技术的研究意义和现状;给出了ATM网络的分层控制体系,指出分层控制为ATM网络管理控制带来了极大的方便;并对VPC层逻辑网络规划、控制的相关问题及其内容进行了分析、分类与总结。     

混合密钥管理的传感器网络聚类算法设计实现

密钥管理是解决传感器网络安全的关键技术。现有的密钥管理机制,不能很好地优化系统的整体性能,基于连通支配集对传感器网络进行聚类,在簇内实现集中式密钥管理,簇间通过通信主干实现分布式密钥管理,从而构建安全的传感器网络。实验表明,通过混合式的密钥管理,可以有效延长网络生命期。     

无线传感器网络智能红外控制节点的实现

无线传感器网络(WSN)是一种全新的信息获取和处理技术,其巨大的应用前景受到学术界和工业界越来越广泛的重视。红外控制技术以其通用性强、价格低廉的优点在生活中应用普遍。将无线传感器网络与红外控制技术相结合,设计了一种具有智能红外控制功能的无线传感器网络节点,该节点利用红外功能模块对红外信号学习并智能存储到EEPROM中,然后按需将预先存储的红外编码发送,达到控制红外终端的目的。另外,利用简单网络管理协议(SNMP)服务器可以对节点的红外控制功能实现远程控制。最后,对新设计的传感器节点进行了测试,证明了该方案的可行性。     

6LoWPAN无线传感器网络移动管理方案

提出了一种跨层的6LoWPAN无线传感器网络移动管理方案。首先提出了6LoWPAN网络体系结构, 基于该体系结构, 提出了一种跨层的移动切换算法。在此算法中, 网络层移动切换与链路层移动切换同时进行, 在三层切换过程中, 移动节点无须转交地址配置, 也无须参与网络层的移动切换过程, 且无须参与移动切换过程, 在二层切换过程中, 移动节点无须扫描所有信道, 通过获取的信道信息直接进行二层切换, 因此降低了切换延迟、丢包率和切换代价。     

无线传感器网络密钥管理方案的研究

无线传感器网络(Wireless Sensor Networks,WSN)是由资源有限的传感器节点构成的无线网络,由于其本身资源方面存在的局限性和脆弱性,使其安全问题成为一大挑战。密钥管理作为安全机制的重要环节,始终是无线传感器网络安全领域的研究热点。本文在研究无线传感器网络安全问题的基础上,对具有代表性的密钥管理方案进行了深入研究,全面分析其利弊以及适应性问题,最后提出了进一步的研究设想。     

Efficient link scheduling for online admission control of real-time traffic in wireless mesh networks

Link scheduling is used in wireless mesh networks (WMNs) to guarantee interference-free transmission on the shared wireless medium in a time division multiple access approach. Several papers in the literature address the problem of link scheduling guaranteeing a minimum throughput to the flows traversing the WMN. However, none of the existing works address the problem of computing a schedule that guarantees that pre-specified end-to-end delay constraints are met. In this paper, we make a first step forward in this direction by defining a link scheduling algorithm that works in sink-tree WMNs, i.e. those whose traffic is routed towards a common sink (i.e. the Internet gateway). Our iterative algorithm exploits a delay-based admission control procedure, devised through Network Calculus, which solves an optimization problem and tests the feasibility of a schedule from the point of view of delay guarantees. Thanks to a clever solution approach for the optimization problem, the iterative algorithm computes feasible solutions in affordable times for networks of several tens of nodes, and is thus amenable to online admission control of real-time traffic.     

多通道ATM 网络鲁棒拥塞控制

拥塞控制对ATM网络有效、稳定运行具有重要的作用，在单瓶颈多通道的网络模型下，基于Smith预估原理，提出一种新颖的鲁棒拥塞控制器设计方案，这种基于速率的拥塞控制可以保证ABR的服务质量(QoS)，理论分析和仿真结果表明，所提出方案收敛速度快，对网络的不确定因素具有较强的鲁棒性。     

Protocols for mobility management in heterogeneous multi-hop wireless networks

Substantial works have recently been reported on the mobility management in single-hop wireless networks (e.g. cellular networks and WLAN hotspots), while there has been an increased interest in multi-hop communications. This has made mobility management in heterogeneous multi-hop wireless networks (HMWNs) really interesting so that both single-hop and multi-hop communication paradigms can be integrated. One of the main research challenges for 4G wireless systems is the identification of a mobility management technique that could integrate different wireless technologies such as WLANs, WMANs and WWANs, operating in infrastructure (single-hop) and infrastructureless (ad hoc or multi-hop) modes. In this article we envision a futuristic HMWN where heterogeneous networks, operating in single-hop and multi-hop modes are integrated to provide increased capacity and enhanced coverage for the users. We summarize various existing mobility management solutions and discuss why these schemes are not adequate for HMWNs, as well as highlighting our view of mobility management issues in HMWNs.     

Parallel communications for ATM network control and management

This paper describes an end-to-end parallel communications scheme based on a vector routing algorithm (VRA) for ATM network control and management. An information string is partitioned into m parts, which are then coded into k > m parts and sent out on k separate subchannels to the receiver. When m of the k parts are received correctly, the original information can be reconstructed. Two desirable effects are achieved in the context of ATM traffic control: (1) the burstiness of the source traffic can be smoothed out by the partition process; (2) the quality of service in terms of error, loss and delay can be controlled using the number of redundant routes k — m as a control parameter. Our results show that VRA is especially suitable for services with highly bursty traffic. We argue that several network management issues, including reliability, evolution and integration, security, and administration and billing can be addressed in a simple manner using the VRA framework.     

基于部署信息的无线传感器网络配对密钥方案

在充分考虑无线传感器网络自身特点的基础上,针对现有无线传感器网络密钥管理中存在的问题,利用Blom矩阵,提出了一个基于部署信息的无线传感器网络密钥管理方案(KPSBM),并从该方案的安全性、连通性、可扩展性、有效性等方面进行分析,并与现有的一些常用方案进行了分析比较,结果表明,KPSBM在这些方面有较好的性能。     

无线传感器网络的设计与部署

首先分析了无线传感器网络与传统无线自组织网络的区别,从侧面阐述了无线传感器网络的特点。接着,讨论了对无线传感器网络设计与部署具有指导意义的无线传感器网络的评价指标。最后,从无线传感器节点到无线传感器网络、从个体到整体、从微观到宏观,较为全面地讨论了无线传感器网络的设计与部署问题,为无线传感器网络的实际应用提供了有价值的参考。     

Routing with admission control in ATM networks

An optimal control parameter, , was developed by optimal control theory for Asynchronous Transfer Mode (ATM) networks. The parameter is related to link utilization, buffer occupancy, system throughput and cell rejection characteristics and is applied to routing and admission control in simulation of a network carrying multiclass traffic. Simulation results show that the parameter produces better performance with respect to cell rejection rate characteristics compared with the traditional control parameter for utilization, .This research has been supported by the ATI as part of the Navy Contract N00140-94-C-BC03. Some parts of the paper were presented at Globecom'94.     

ATM交换连接控制与UNI信令协议

ＡＴＭ是一种面向连接的信息转移模式。这些连接分为永久型虚连接（ＰＶＣ）和交换型虚连接（ＳＶＣ）。提供ＰＶＣ是ＡＴＭ网络管理的功能之一，而提供ＳＶＣ则是信令系统的基本任务。完整的信令系统包括ＵＮＩ信令和ＮＮＩ信令。本文对ＵＮＩ信令系统的功能、体系结构及有关协议进行简要的描述，从而有助于信令软件的设计。     

一种节能混合无线传感器网络MAC协议

针对无线传感器网络的节能和网络性能流量自适应的需求,在Z-MAC协议的基础上,提出了EHMAC协议。经过分析表明,EHMAC在保持Z-MAC高信道利用率和低延迟的同时,可以减少Z-MAC低功耗侦听机制造成的大量串音能耗以及preamble传输所造成的网络开销。此外,EHMAC对Z-MAC在内的TDMA类协议无法应对的非对称隐藏终端问题提出了解决方案,取得了较高的网络吞吐量和较低的端到端延迟。