手持终端设备中基于对象交换协议的红外传输功能的设计与实现

通过红外进行文件传输,在手持终端设备中具有较高的实用意义.在可选的红外协议中,红外对象交换协议(OBEX)具有简单、实用、可移植性强等优点而被广泛应用.本文详细分析了利用对象交换协议进行文件传输的步骤,并给出了基于嵌入式linux系统的具体实现方案,最后介绍了在便携式多媒体中心的应用平台上红外传输功能的实现情况.     

OBEX在蓝牙开发中的应用

OBEX作为一种基础协议,以对象模型封装信息数据,以会话协议规范传输应用,在以信息传输为底层实现的各项应用中得到了广泛的应用。在蓝牙技术的开发应用中,OBEX是很多应用剖面的底层协议,在其基础上封装实现了不同蓝牙剖面应用,大大拓展了蓝牙技术的应用领域,所以有必要深入研究并剖析OBEX协议。文中从对象模型和会话协议两个方面详细介绍了OBEX协议,并解析了其在蓝牙OPP、PBAP上的绑定实现。     

元器件快讯

用于嵌入式红外线通信的IrDA软件解决方案安捷伦科技公司 (AgilentTechnologies)宣布推出一种快速、经济的IrDA协议堆栈软件解决方案。该软件在新型移动电话、PDA、办公设备、数码相机以及医疗设备和工业自动化设备等产品中嵌入兼容IrDA(红外线数据协会)的无线通信功能提供了便利。安捷伦的HSDL -S100IrDA协议堆栈提供了管理数据传送所需的所有功能。它采用IrDA标准、速率高达4Mb/s ,可在任何支持ANSIC编程语言的平台上运行。安捷伦的IrDA协议堆栈包括对象交换(OBEX)和移动通信红外线(IrMC)模块 ,可促进无线文件的交换及数…     

SyncML在蓝牙车载免提装置中的应用

SyncML是移动设备间数据同步的一种通用协议,本文通过对该协议的分析,在SyncML OBEX绑定协议的基础上,结合电话簿vCard规范,在一款蓝牙车载免提装置中实现了SyncML在电话薄数据同步中的应用,从而保证了用户手机和蓝牙车载免提装置中电话薄的一致性。     

SyncML在蓝牙车载信息娱乐设备上构设计与实现

通过把SyncML绑定在蓝牙的OBEX协议上,笔者在一款蓝牙车载信息娱乐设备中开发了SyncML服务器,实现了蓝牙手机和车载信息娱乐设备间的电话薄同步应用.本文首先介绍蓝牙协议栈结构,然后分析SyncML OBEX绑定协议实现的关键点,并结合vCard规范详细介绍电话薄同步应用的具体实现.     

爱立信为辽宁、甘肃和内蒙古进行GSM网络扩容

近日，辽宁移动、甘肃移动和内蒙古移动纷纷选择爱立信作为系统设备和服务提供商进行GSM网络扩容，合同总金额逾7000万美元。根据协议，爱立信将为辽宁省14个城市提供包括移动交换中心（MSC）、基站控制器（BSC）、基站（BTS）、本地寄存器（HLR）在内的软硬件系统设备，同时提供培训，备件和相应工程服务。为了实现更加合理的网络结构，辽宁移动在此次扩容中开始在大连采用混合双频网结构，并在大连、盘锦和辽阳的交换领域全部使用爱立信设备以取代原其他厂家在GSM1800MHz的交换设备，经本期扩容后爱立信设备在辽宁的交换容量将达…     

SOAP的分析研究

简单对象访问协议（Simple Object Access Protocol，SOAP）是一个基于扩展标记语言的在分散或分布式环境中实现信息交换的简单协议，其主要目的是促进不同技术之间的可互用性。本文先介绍了SOAP规范的组成；再详细介绍SOAP消息的结构及其交换；最后采用SOAP技术实现远程学生信息管理服务，该系统采用Java语言开发，进行跨网络的远程学生信息管理，从而实现了SOAP在分布式环境中的信息交换的应用。     

物联网移动RFID系统匿名访问控制认证密钥交换协议

针对物联网移动RFID系统标签隐私信息的访问控制以及用户身份隐私保护问题,本文采用身份加密和属性加密相结合的方法,建立了IB-AB-eCK安全模型,设计了基于身份及属性的认证密钥交换协议IB-AB-AKE。基于IB-AB-AKE协议,提出了移动RFID手机与信息服务器之间认证密钥交换协议,实现了在保护移动RFID手机用户身份隐私的同时,根据标签所有者定制的访问控制策略进行标签信息的访问控制认证和会话密钥交换,防止了隐私信息被非法访问。分析表明,IB-AB-AKE协议在IB-AB-eCK模型下是安全的,且在通信次数、通信量及计算量方面具有优势。      

MPLS架构下的移动IP技术

本介绍了多协议标记交换(MPLS)和移动IP技术的基本原理，并在此基础上给出了工作在MPLS机制下的移动IP网络组成模型，同时描述该模型的基本工作原理。最后分析了MPLS架构下移动IP的技术优势并对其应用前景进行了阐述。     

基于USB接口的OTG应用技术开发

随着移动终端的普及,为了不使用PC,直接在移动终端间进行数据交换,提出了OTG技术.USB OTG （On-the-Go）标准在完全兼容USB2.0的基础上,追加了HNP（Host Negotiation Protocol）和SRP（Session Request Protocol）协议.在硬件方面增添了更小的连接器和电缆,包括袖珍型的A插头和插槽（Mini-A）,袖珍型的AB插槽（Mini-AB）.通过HNP和SRP协议可以实现主从设备的交换,从而实现脱离PC的移动设备间数据的直接交换.     

OBEX Over IrDA: Performance Analysis and Optimization by Considering Multiple Applications

OBEX (Object Exchange Protocol) is a session protocol designed to exchange all kind of objects between portable devices using different ad hoc wireless links including IrDA and Bluetooth. This paper develops a mathematical model for OBEX over the IrDA protocol stack by considering multiple applications and presence of bit errors. The model is also verified by simulation results. We derive throughput equations and carry out an optimization study focusing on four major parameters: OBEX packet size, TinyTP (IrDA transport layer) buffer size, IrLAP (IrDA link layer) frame and window size. Equations are derived for the optimum IrLAP window and frame sizes. Numerical results show significant improvement on OBEX performance using the optimized parameters. The major contribution of this work is the modelling of OBEX including the low layer protocols and optimization of the overall throughput by appropriate parameter selection     

OBEX研究及.net Compact框架实现红外通信的应用

IrDA是一种利用红外线进行通信的点对点通信的技术.设备间的红外线通信具有方便快捷、无需额外硬件支持等特点.基于对OBEX协议的研究,本文在Visual Studio.net Compact框架下,设计并实现了两个独立设备利用红外接口进行信息传输的功能.     

Optimization of IrDA IrLAP link access protocol

The widespread installation of millions of Infrared Data Association (IrDA) infrared (IR) ports in mobile devices for wireless communication applications necessitates for throughput performance optimization of the IR links at the IrDA link access protocol (IrLAP) link layer. For IrDA connectivity, link-layer throughput optimization is important for any line bit-error rate (BER). The paper provides a mathematical model with which we derive a simple equation linking IrLAP throughput with physical and link-layer parameters. Simple equations for optimum values of window size and frame length for maximum link-layer throughput as a function of BER are derived. A study of the importance of parameters such as link minimum turnaround time and F-timer time out period is presented. Finally, a protocol improvement that utilizes special supervisory frames (S frames) to pass transmission control is proposed to deal with delays introduced by F-timer expiration. Results indicate that employing the special S frame highly improves throughput performance when optimum window and frame-size values are implemented.     

IrBurst Modelling and Performance Analysis in the Presence of Transmission Errors

IrBurst is a session/presentation layer protocol dedicated for high speed large volume information transfer over IrDA links. The protocol is developed by IrDA in order to complement the existing protocol OBEX which is best suited for small files. This paper presents a mathematical model for IrBurst over the IrDA protocol stacks taking into account the presence of bit errors and multiple simultaneously applications. The performance of IrBurst is examined considering TinyTP buffer sizes and the number of IrBurst application connections as parameters. The contribution of this work is to develop a mathematical model for IrBurst, investigate the compatibility of IrBurst to low layer protocols, as well as providing suitable design guidelines for IrDA devices for high performance of IrBurst. Pi Huang received the B.Sc. degree in Electrical and Electronic Engineering from University of Central Lancashire, U.K., in 2001, the M.Sc. degree in Telecommunications from University College London, U.K., in 2002 and the Ph.D degree in the Personal Wireless Networks and Outdoor Optical Links from Bournemouth University, U.K., in 2006. He is currently working in wireless solution division of British Telecom. His research focuses on performance modelling and analysis as well as discrete-event simulation of wireless communication protocols and wireless communication networks. He has published over 20 papers in the areas of wireless communications. Anthony C. Boucouvalas has worked at GEC Hirst Research Centre, and became Group Leader and Divisional Chief Scientist until 1987, when he joined Hewlett Packard (HP) Laboratories as Project Manager. He joined Bournemouth University in 1994 and became a Professor in Multimedia Communications in 1996, and in 1999 became Director of the Microelectronics and Multimedia Research Centre. His current research interests span the fields of wireless communications, optical fibre communications and components, multimedia communications, and human-computer interfaces, where he has published over 200 papers. He has contributed to the formation of IrDA as an industry standard and he is now a Member of the IrDA Architectures Council. He is a Fellow of Fellow of the Royal Society for the encouragement of Arts, Manufacturers and Commerce, (FRSA) and a Fellow of IEE, (FIEE). In 2002 he became a Fellow of the Institute of Electrical and Electronic Engineers (FIEEE), for contributions to optical fibre components and optical wireless communications. He is an Editor of numerous Journals and in the Organising committee of many conferences.     

基于IrDA标准的红外无线数字通信及应用

概述了红外无线通信的概念，介绍了IrDA通信协议，在此基础上设计了一种基于单片机的通用红外通信接口模块，它支持IrDA协议，采用串行输入输出，可以做为附加通信模块方便地集成到各种设备和仪器仪表中。     

Performance modeling of the IrDA protocol for infrared wirelesscommunications

This article presents a performance analysis of the IrDA protocol used for short-range IR data communication using an analytical mathematical model. The IrDA protocol specifies a protocol stack for reliable short-range infrared wireless data communication between devices with the data link layer (IrLAP) being an HDLC derivative. The mathematical model is based on unidirectional data transfer and uses the concept of the virtual transmission time, which provides the average end-to-end transmission time of a packet, incorporating the time for retransmissions if packet errors occur or other enforced delays. Analytical results are produced for throughput against packet size, BER and minimum turnaround time. They indicate certain limitations of the protocol for efficient throughput at high data speeds, and indicate that the maximum frame size and window size should be increased and the minimum turnaround time minimized for improved results     

Future personal "e-payment": IrFM

There is widespread distribution of millions of mobile devices such as mobile phones and PDAs with infrared data association (IrDA) ports to consumers worldwide. Rapid advancements in both device technology and users' capabilities are the foundations for a new digital payment system, which promises to change the traditional method of payments. By utilizing standard IrDA indoor infrared technology, infrared financial messaging (IrFM) is a financial messaging specification with great prospects for future digital payment systems. In this article, we carry out a comprehensive analysis of IrFM, clarify the benefits of using such a system, and develop a model which allows us to identify the significance of major performance factors of digital payment systems. Issues concerning connection speed, security, reliability, simplicity, and interoperability of IrFM are investigated.     

Wireless infrared communication system based on edge position modulation

Driven by the Infrared Data Association (IrDA) wireless infrared communication has become a very popular and widely used method for short range data transmission between mobile devices like laptops, PDAs and mobile phones. Quality and speed of infrared communications are mainly limited by the bandwidth of the infrared transceivers. Therefore it is important to use a modulation technique with a high bandwidth efficiency, while simultaneously maintaining a low bit error rate and high power efficiency. Consequently, IrDA has continuously improved the modulation techniques of its standards (IrDA, 2001) by introducing Return to Zero inverted (RZI), 4 Pulse Position Modulation (4-PPM) and HHH(1, 13), whereby the latest is basically a 2/3-rate Run-Length-Limited (RLL) code (Hirt, Hassner, Heise, 2001). Recently the authors have published a novel modulation scheme called Edge Position Modulation (EPM) with Run-Length-Limited (RLL) coding (Lüftner et al., 2003). This article will continue this work by presenting a completely new RLL(5, 12) code that is optimized for EPM.     

一种快速IrDA的设计与FPGA实现

简单介绍了IrDA协议以及在IrDA协议中数据传输的格式;根据快速IrDA的功能将其划分成若干模块,进行层次化设计,详细描述了在快速IrDA中的几个主要(关键)模块的实现方法;利用Verilog HDL实现了该设计,并利用Metor公司的Modelsim进行了仿真测试以及Synplicity公司的Synplify进行了综合来验证该设计的正确性。