蜂窝移动定位技术的发展与应用

文章介绍了移动通信系统中无线定位技术的应用，对基于网络的无线定位方案中几类常用的无线定位方法以及影响定位精度的主要因素、对策进行了分析和讨论，最后提出了无线定位技术中有待进一步研究的课题。     

定位技术在无线传感器网络中的应用

被誉为21世纪三大技术之一的无线传感器网络出现于20世纪90年代,之后受到了越来越多的关注。定位技术是无线传感器网络的核心技术之一,是网络大范围应用的基础。文章介绍了无线传感器网络定位技术在网络中的应用,描述了常用的定位方法及目前无线传感器网络定位算法的研究现状,结合网络特征讨论了下一步研究中需要解决的问题。     

无线传感器网络节点定位技术综述

无线传感器网络在许多领域有着重要的科研和使用价值,网络中传感器节点自身定位可为无线传感器网络的很多应用提供基础信息,是重要研究方向之一.从无线传感器网络节点定位技术的研究意义与应用价值出发,介绍了节点定位技术的基本原理与方法,并讨论了定位算法的评价标准,最后对节点定位技术的发展方向进行了展望.     

基于移动通信网络无线定位的研究

无线定位技术是第３代移动通信研究的一个重要方面,也是当今十大热门电信技术之一,基于移动通信网络的无线定位技术是其中的重要组成部分。首先点明了移动通信系统中无线定位的意义,然后介绍了基于移动通信网络无线定位的原理和技术,并重点阐述了基于移动通信网络无线定位的方法、结构及特点,从而为其他定位技术的研究和开发提供了新的思路与方法。     

基于于移动通信网络无线定位的研究

无线定位技术是第3代移动通信研究的一个重要方面,也是当今十大热门电信技术之一,基于移动通信网络的无线定位技术是其中的重要组成部分.首先点明了移动通信系统中无线定位的意义,然后介绍了基于移动通信网络无线定位的原理和技术,并重点阐述了基于移动通信网络无线定位的方法、结构及特点,从而为其他定位技术的研究和开发提供了新的思路与方法.     

第三代移动通信系统WCDMA无线定位技术及其应用

无线定位技术是第三代移动通信系统中一个非常有前号的技术本文首先对无线定位技术的网络构架进行了描述,然后阐述了各个关键的网络元素的功能,然后分析研究了目前在3GPP标准中的几种定位方法以及各个定位方法的信令流程,最后对3G中无线定位技术的应用前景进行了展望。     

CDMA2000 1X位置服务平台实现方案

在CDMA系统中采用的定位技术被叫做“混合定位技术”，也就是说，为了达到定位的目的，采用了多种定位技术。这些技术大致可以分为两类：基于网络的定位技术和基于移动台(MS)的技术。     

WCDMA无线定位技术及其应用

无线定位技术是第三代移动通信系统中一个非常有前景的技术。文章首先对无线定位技术的网络构架进行了描述,并阐述了各个关键的网络元素的功能,然后分析研究了目前在3G P P标准中的几种定位方法以及各个定位方法的信令流程,最后对3G中无线定位技术的应用前景进行了展望。     

无线传感器网络定位测量模型方法研究

首先论述了面向无线传感器网络定位技术的基本原理,对常见的定位方法做了综述;分类研究了无线传感器网络中常见的定位模型和测量方法,对定位技术中应用到的基本测量技术和测量模型以及可能存在的误差进行了分析;最后对衡量当前存在的定位系统和定位方法的标准做了讨论,并总结了定位系统优劣的基本评价标准。     

浅谈蜂窝移动系统中的定位技术

随着CDMA技术的应用与发展,蜂窝移动通信系统呈现出迅猛发展的势头。蜂窝网络中各种基于移动台位置的服务,如公共安全服务、基于移动台位置的计费、网络规划与设计、网络QoS和无线资源管理等,无不与准确定位移动台位置有关,使得对蜂窝网络中移动台定位技术的研究日趋活跃。本文综合论述了无线定位技术在第三代移动通信系统中的发展与应用现状,并对影响蜂窝网络无线定位精度的原因进行了详细分析与研究,最后指出了以后的研究方向。     

无线定位估计的信息融合模型研究

近年来基于蜂窝网络对移动台进行定位估计的无线定位技术受到广泛的关注,目前的几种基于网络的定位方法在不同的信道和网络环境中表现出的性能各不相同,还没有一种技术能在各种不同信道和网络环境中都能表现出最佳性能,满足对蜂窝网络移动台定位的精度要求。数据融合是一种对不同类型数据进行融合,以取得比单一方法和技术更佳的数据输出的技术。论文将信息融合应用于无线定位之中,对无线定位的信息融合模型进行了深入的研究。     

Optimal Switch-Concentrator Location for a Telephone Network

This paper considers the problem of the optimal introduction of digital switching equipment into an existing analog local telephone network. The criterion used is the present worth of annual charges. Using certain plausible assumptions, this multilocation dynamic problem is shown to reduce to an equivalent static problem. The latter can be expressed as a classical plant location problem for which several solution techniques are available in the operations research literature.     

Fault diagnosis of analog circuits

In this paper, various fault location techniques in analog networks are described and compared. The emphasis is on the more recent developments in the subject. Four main approaches for fault location are addressed, examined, and illustrated using simple network examples. In particular, we consider the fault dictionary approach, the parameter identification approach, the fault verification approach, and the approximation approach. Theory and algorithms that are associated with these approaches are reviewed and problems of their practical application are identified. Associated with the fault dictionary approach we consider fault dictionary construction techniques, methods of optimum measurement selection, different fault isolation criteria, and efficient fault simulation techniques. Parameter identification techniques that either utilize linear or nonlinear systems of equations to identify all network elements are examined very thoroughly. Under fault verification techniques we discuss node-fault diagnosis, branch-fault diagnosis, subnetwork testability conditions as well as combinatorial techniques, the failure bound technique, and the network decomposition technique. For the approximation approach we consider probabilistic methods and optimization-based methods. The artificial intelligence technique and the different measures of testability are also considered. The main features of the techniques considered are summarized in a comparative table. An extensive, but not exhaustive, bibliography is provided.     

A Systematic Review of Localization in WSN: Machine Learning and Optimization-Based approaches

In recent years, wireless sensor networks (WSNs) have been widely used in various applications. The localization problem has been identified as one of the biggest problems faced by WSNs. The traditional localization techniques may not be able to handle the issues during the scenario to estimate the location of sensor nodes due to anchor mobility, mobile WSNs, latency, energy harvesting, unfavorable environmental states, and many more issues. However, these issues open the door for the amalgamation of machine learning (ML) and optimization techniques with localization techniques. Motivated by the earlier discussion, we explored various ML and optimization techniques to estimate the location coordinates in a sensor network in this paper. Finally, a comparison of existing ML algorithms concerning optimization techniques has been presented, highlighting their improved outcomes. This research offers a detailed survey by exploring the various parameters for location estimation through tabular forms by incorporating ML and optimized localization techniques. A survey of surveys is also presented to identify the key limitations of existing surveys and to introduce the novelty in the comprehensive study done in this paper. A year-wise evaluation of ML Techniques with localization (2011–2022) is also discussed and presented over various performance parameters, including energy-efficiency, accuracy, error, and complexity. This discussion concluded that Hybrid Techniques are least explored for using optimized localization machine learning. Further, a summarized discussion of the various comparison tables paves the path for future research in the area of localization in WSN.     

Privacy Provisioning in Wireless Sensor Networks

Privacy is a necessary component of any security discussion. Privacy and security must be considered separately as well as together. Threads of privacy are visible throughout the procedure of building security solutions for any system. The notions for privacy also play an important role in the technical implications of privacy preservation within any network or its subsystems. Analyzing the mitigations and protections for privacy are considered in privacy notions. The privacy notions being theoretical systems and identified vulnerabilities in the sensor networks not being mapped to such privacy preservation notions necessities the analytical review of privacy provisioning in wireless sensor network (WSN) being formalized within a framework consisting or the vulnerabilities associated with each component of the network and mechanisms of privacy preservation along with the privacy notions. The current research paper provides an analytical review of the privacy provisioning in WSNs with the perspective of development of a proposed framework for privacy notions and quantitative as well as qualitative measures associated with the privacy preservation in sensor network mapped with the various techniques implemented for privacy preservation of different components of the network and the network as a whole. This analytical review has been done on the basis of set of beliefs that an adversary has while launching an attack on the network. Further the existing techniques for privacy preservation of receiver and source node location, location of sink node, traffic analysis prevention and preserving temporal privacy in WSN have been analyses on the basis of adversary’s set of beliefs’ mitigated by them and the notion of privacy implemented by these techniques like k-anonymity, l-diversity or t-closeness. The present effort aims to provide the researchers with an insight of the new concept of belief mitigation for privacy provisioning in WSN.     

基于混合GPS/TDOA的CDMA网络无线定位研究

介绍了CDMA网络的无线定位技术,分析了不同技术的适用性和优缺点,提出了一种混合GPS TDOA定位方法。该方法将GPS和TDOA测量值相结合,弥补了独立的GPS和基于网络定位方法的不足,为CDMA网络无线定位提供高精度的解决方案。     

ZGLS: a novel flat quorum-based and reliable location management protocol for VANETs

In location management services, a destination advertises its position attributes to a set of vehicles called location servers while, a source obtains these attributes from such location servers to track destination. The location management techniques in VANET have been categorized into flooding-based, flat hashing-based, hierarchical hashing-based and hierarchical quorum-based techniques. In flooding-based location service, destination information is flooded to the entire network which results into high congestion, low throughput and non-scalable network. In flat hashing, a global hash function is applied to compute location servers of each destination which results into higher delay, drop and signaling overhead in large VANETs. In hierarchical hashing, global hash function computes location servers of destination in hierarchical order. It therefore suffers from handover signaling between servers, high load on the top hierarchy and location query delay when source and destination are apart. In hierarchical quorum-based, location servers are identified cluster-wise and therefore it also suffers from the problems similar to hierarchical techniques. To overcome these problems, ZoomOut Geographic Location Service (ZGLS) protocol is proposed which introduces flat quorum-based location management service. In contrast to the aforementioned techniques, the novelty of ZGLS lies in the fact that it has shifted the location server role from hashing-based or clustering-based geographic areas to few 1-hop neighbours, called relatives. The proposed protocol creates a chain of relatives to provide positioning and tracking service. To evaluate signalling overhead, timeliness and the reliability of update and query packets, ZGLS is compared with RLSMP and HRHLS through ns-2 simulations. The results reveal that ZGLS stands out as a better choice for large-scale sparse and dense VANETs.     

WDM光网络的保护和恢复技术

文章概述了IP、SDH和WDM层网络的生存性技术,重点介绍了光传送网的光层生存性技术与光网络恢复技术,还对故障定位、多层生存性机制的协调等问题进行了简单介绍,最后给出了一个业务配置RWA算法与恢复RWA算法的实际方案。     

虚拟局域网

虚拟局域网是网络用户独立于网络物理配置和位置的一个逻辑组合，综结合了网络交换和管理功能，使网络根据用户需要分割成多个逻辑网，管理员对分布于各个网段的用户视作在同一逻辑网中进行管理，在网络性能、保护用户投资及向ＡＴＭ过渡方面具有很好的性能。本文对虚拟局域网技术进行综述。