基于ATM的无线宽带网络

本文首先介绍了无线宽带网络的技术背景和空中接口,然后讨论了无线宽带通信的核心技术－无线ＡＴＭ的基本原理,如网体系结构、信元格式、协议栈,以及关键技术等,最后给出了现有的无线宽带网络的实验系统和它的标准化进程。     

压电有机聚合物敷层光纤的相位调制特性

本文研究了压电有机聚合物敷层光纤的相位调制特性。采用镀敷和整平工艺，平滑了相移－频率响应曲线。这种敷层－光纤系统具有宽的频域（１ＫＨｚ－５０ＭＨｚ和一定的相移灵敏度     

聚合物光纤光谱特性研究

本文根据不同的精度要求,采用CCD光谱仪和高精度光谱仪测量了聚合物光纤的光谱损耗、吸收谱与发射谱,分析了这几种光谱特性,讨论了有源聚合物光纤中的拉曼谱对荧光谱的影响等现象。     

聚合物光纤在中国的应用发展

聚合物光纤在中国的应用是从20世纪80年代中后期首先在丁艺品的应用开始的，目前已成为聚合物光纤在中国最大的应用领域，随后向广告、显示和装饰装潢应用领域扩展，至20世纪90年代末期，聚合物光纤向照明、传像、传感和短距离数据传输应用发展，现已取得很大的进步。     

Architecture and Experimental Framework for Supporting QoS in Wireless Networks Using Differentiated Services

This paper describes the design and implementation of an enhanced Differentiated Services (Diffserv) architectural framework for providing Quality of Service (QoS) in wireless networks. The Diffserv architecture has been recently proposed to complement the Integrated Services (Intserv) model for providing QoS in the wired Internet. The paper studies whether Diffserv, as defined for wired networks, is suitable for wireless networks. The proposed wireless Diffserv framework takes into consideration several factors, including signaling requirements, mobility, losses, lower wireless bandwidth and battery power constraints. It identifies the need for supporting signaling and mobility in wireless networks. The framework and mechanisms have been implemented in the wireless testbed at Washington State University. Experimental results from this testbed show the validity of the proposed Diffserv model and also provide performance analyses. The framework is also designed to be extensible so that other researchers may use our implementation as a foundation for implementing other wireless network algorithms and mechanisms.     

单模石英光纤和塑料光纤自动耦合系统

作为短距离通信网络的理想传输介质,塑料光纤(POF)具有广阔的应用前景.然而单模塑料光纤和其他光纤之间连接的连接器目前还没有产品.研制了一种可实现单模塑料光纤和单模石英光纤之间的自动连接(耦合)系统.该系统通过上位机控制部分对于光功率计和采集图像的反馈数据进行分析处理,进而驱动高精度位移步进电机,使两光纤达到精确耦合,从而为单模塑料光纤和塑料光纤光栅的进一步研究打下了坚实的基础.     

Multimode Optical Fiber Displacement Sensor

The structure of an intensity modulation optical fiber sensor is introduced.The principle of the sensor which can detect minor displacement by use of minor curve in dark ground is described.Complex experiment shows that the multimode optical fiber not only has the abilitly of detecting the displacement of less than 0.1 nm,but also exhibits characteristics of wide dynamic range and good linearity.     

对中国发展宽带接入及光纤的思考

宽带接入发展趋势正从传统的铜线接入向。有线铜退光进,无线宽带移动化,有线无线相互补充。实现无缝接入。的目标演进。光纤宽带是固网宽带接入发展的必然选择。光接入面临多重挑战,需要综合考虑建设与运营维护、无源光网络光线路终端容量设置、光纤宽带对无源光网络（PON）光网络单元的要求、光纤宽带设备的管理、综合业务承载能力、多业务承载对业务控制层的影响等问题。     

Broadband Wireless Access Solutions - Progressive Challenges and Potential Valueof Next Generation Mobile Networks

The growth in mobile communication will accelerate over the next years. Today most of the mobile subscribers use cellular services only. But this will change in the near future towards broadband wireless access services like WiFi and WiMAX. This paper describes a fundamental overview of the broadband wireless access technologies and outlines the market view, major trends and introduces OFDM technologies. New developments for integration of broadband wireless access into the operators' infrastructure are also discussed.     

单偏振单模微结构聚合物光纤的设计

设计了一种聚甲基丙烯酸甲酯(PMMA)基的单偏振单模(SPSM)微结构聚合物光纤(MPOF)。采用全矢量平面波展开法并结合完美匹配边界条件,对其偏振特性进行了理论模拟。详细讨论了微结构光纤参数的变化对单偏振单模带宽和工作波长的影响,发现在0.57～0.71μm的可见光波长范围,由于基模两个正交偏振模的截止波长不同,这种微结构聚合物光纤只能传输基模中的一个偏振模。光束传播法计算表明,在波长0.65μm处具有7圈空气孔的单偏振单模微结构聚合物光纤的传导偏振模约束损耗仅为1.24dB/m,这种低损耗的单偏振单模微结构聚合物光纤可有效消除传统保偏光纤固有的偏振串扰和偏振模色散。     

聚合物光纤技术的最新进展

本文介绍聚合物光纤领域中梯度折射率聚合物光纤的带宽、谱损、稳定性和高速传输实验,以及氟化聚合物光纤、聚合物光纤连接器和放大器方面研究的最新进展．     

高双折射微结构聚合物光纤研究

详细介绍了一种具有强各向异性的徽结构聚合物光纤(MPOF)。这种徽结构塑料光纤的研究结果显示它具有高双折射特性。此外．还介绍了一种自制简单模具，可方便地将圆柱形光纤包层管压制成内外都是六角形的结构，在这种六角形光纤包层管中堆积的毛细管规则阵刊的形状更容易保持完整，从而在制作工艺上能对光纤中引入的微结构提供保障。     

聚合物光纤传感器及其在环境污染监测中的应用

描述了聚合物光纤(polymer optical fiber,POF)传感器的主要特点,介绍了国内外在该领域的研究现状,及其在环境污染监测中的应用,同时讨论了研究的发展方向。     

聚合物光纤传感器及其在环境污染监测中的应用

描述了聚合物光纤（polymer optical fiber,POF）传感器的主要特点,介绍了国内外在该领域的研究现状,及其在环境污染监测中的应用,同时讨论了研究的发展方向。     

线性光纤传输宽带射频信号技术及实现

针对卫星通信宽带射频信号地面和舰船上有线传输距离短、传输损耗大的问题,提出了利用线性光纤技术传输卫星通信宽带射频信号的解决途径和方法。分析了线性光纤与数字光纤的传输模型。介绍了线性光纤技术在宽带射频信号有线传输领域的特点和优势,并对线性光纤技术在国内外的应用现状和前景进行了分析说明。     

微结构聚合物光纤化学修饰的pH值传感探头

为了拓展微结构聚合物光纤(MPOF)在化学传感领域内的应用研究以及对MPOF孔道内壁功能化修饰技术的深入研究, 首先对36孔的MPOF孔道内壁进行酸催化水解处理, 随后采用化学键合的方式将荧光探针曙红通过偶联剂负载于MPOF孔道内壁, 从而制成用于pH值测定的传感探头。该传感探头被修饰后的多个孔道可以容纳微量的待测溶液, 待测物与孔道内壁的荧光探针作用后, 光信号将可以沿光纤传输, 并被检测。整个化学反应的传感过程是在孔道内进行的, 传导的光束能够和敏感材料相重叠, 利于微量分析同时避免了对敏感膜的损坏。实验结果显示pH值在2.0～4.4范围内与荧光强度呈线性关系, 该传感探头的重现性良好, 并且采用此修饰方法制备的MPOF传感探头对于荧光探针的固定性比较好, 无明显泄漏。     

MAPON: Master Antenna Passive Optical Network for the Distribution of Digital Video Broadband Services in the European ACTS-CRABS Project

The European ACTS-CRABS project addresses theproblem of delivering broadband and interactivedigital video channels over a wireless 40 GHz fixedpoint-to-multipoint cellular network connectingantennas typically placed on the top of office orapartment buildings. An important issue of thisproject is the final distribution of the signal insidethe building itself. The proposed solution is based ona passive optical network (MAPON) designed to deliverthe signal from a Master Antenna to the final usersapartment. This paper presents an overview of theMAPON solution architecture and hardware, togetherwith the results obtained on an installed testbed. Theissues of low-cost design, system bandwidthlimitations, transmitter clipping and power budget areaddressed, together with the proposed solutions. Weexperimentally measured a power budget that wouldallow the distribution to up to 32 users over lengthsof the order of 150 m.     

In-Cell Frequency Reuse for Broadband Indoor Wireless Systems Using Sectored Antennas

This paper proposes a hybrid Space-Time Division Multiple Access (S-TDMA) for broadband indoor wireless systems using sectored antennas. It is shown that portables which are located in different sectors of the indoor microcell may be able to reuse the same frequency and the same time slot. However this requires careful scheduling of packet transmissions in order to avoid transmitting packets that would jam each other during the same time slot. It is proposed that the scheduling be performed by the base station, i.e., a central control architecture. If the number of channels (simultaneous transmissions) is larger than two, the optimum scheduling algorithm, the one that maximizes the number of packets transmitted per frame, is in the NP-Complete class of problems and so can not be solved in real time. Therefore a sub-optimum algorithm named the First Fit Algorithm (FFA) is proposed for frame scheduling and its performance is investigated through measurement results obtained in some typical indoor environments. Computer simulations based on the measured data showed that the FFA can provide a large capacity gain. For example, for a minimum acceptable signal-to- interference ratio of 10 dB and for a sectorization level ten (using ten sectors in the base station) the FFA can multiply the capacity by 3.6 in a typical open indoor location. This means that on average, 3.6 packets can be transmitted per time slot while using the same radio frequency.     

掺染料聚合物光纤放大器的瞬态增益性能分析

文章使用速率方程的方法,给出了一个能够描述掺有机染料聚合物光纤放大器增益性 能的模型,考虑了染料三重态能级对速率方程的影响,得到了放大器的瞬态增益特性。结果表明在7kW泵浦功率下,信号可以获得27dB的增益。     

高带宽梯度折射率塑料光纤的数据传输试验

本文首先介绍了高带宽梯度折射率塑料光纤的制造方法和性能;其次阐述了在高带宽梯度折射率塑料光纤上进行的单信道和多信道的数据传输试验.