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1.
余涛  黄书宝  葛昭攀  陈宇亮  施安 《计算机工程》2005,31(14):122-124,201
无线局域网(WLAN)技术日趋成熟,如何为WLAN用户提供实用、方便的服务是当前推动WLAN进一步发展的“瓶颈”。论述了WLAN的现状及困境;提出了结合地理信息系统技术(GIS),开发WLAN环境下的位置服务;重点讨论了基于WLAN信号强度的定位方法、系统框架和WLAN位置服务的主要功能;最后根据原型试验,详细分析了影响WLAN定位精度的主要因素及改善方法。  相似文献   

2.
基于无线网络的入侵检测系统研究与设计   总被引:5,自引:0,他引:5  
本文对无线局域网络(WLAN)的入侵方式、入侵接入进行了分析,总结提出了WLAN网络中入侵检测技术系统的设计要求,结合有线网络中比较成熟的入侵检测技术,设计了一个分布式WLAN入侵检测系统(WDIDS)模型,我们认为该模型对研究无线局域网络入侵检测技术有一定的参考价值。  相似文献   

3.
伍朝阳 《福建电脑》2009,25(2):130-130
本文对无线局域网络(WLAN)的脆弱性进行了分析,结合有线网络中比较成熟的入侵检测技术,设计了WLAN网络中入侵检测系统(IDS)模型,我们认为该模型对研究无线局域网络入侵检测技术有一定的参考价值。  相似文献   

4.
随着网络安全的发展和无线局域网络的应用,WLAN的安全越来受到重视。文章分析了WLAN网络链路层的安全问题,结合无线局域网络安全标准802.1li,对WLAN网络中加密与认证技术中的SSID、MAC、WEP、WPA、WPA2等安全技术问题进行了介绍,并重点阐述了安全技术的应用选择方法,最终得出了在加密技术成本、安全需求成本都能兼顾的情况下应该选择WPA2加密技术来保障无线局域网络安全的结论。  相似文献   

5.
基于WiFi和ZigBee的井下人员无线跟踪与定位系统的设计   总被引:2,自引:0,他引:2  
针对现有矿山人员定位系统成本高、安装复杂、只能区域定位等问题,提出了一种基于WiFi和ZigBee技术的井下人员无线跟踪与定位系统的设计方案和一种符合矿山实际要求的基于一维线性空间的实时定位方法,详细介绍了该系统的软硬件设计。该系统采用WiFi技术组建无线语音局域网络,采用ZigBee技术组建无线传感器监测网络,通过井下综合分站同时发射WiFi和ZigBee无线信号,实现了井下实时通信信号和定位信号的覆盖。该系统已实际应用,效果良好。  相似文献   

6.
4G时代,无线WLAN网建设与应用发展迅速,运营商在低成本建设WLAN网的同时,也对未来WLAN网的建设提出了更高目标。本文从无线WLAN网的特点、概况等方面简要介绍了无线WLAN网的工程建设概况和无线WLAN网络覆盖方案的设计建设思路,重点分析了AC与AP设备在不改变本地网实际组网的情况下的组网方式与建设模式,并简要列举了无线WLAN网络典型场景的解决方案,包括室内多网络合一的无线综合分布式系统覆盖、小型AP分布系统方式覆盖、室内AP直接覆盖和室外AP覆盖等建设方式,为WLAN网络工程建设提供了参考。  相似文献   

7.
本文研究了包括IEEE 802,11a/b结构特征在内的IEEE 802,11无线局域网(WLAN)的特性,提出了基于IEEE 802.11a/b MAC的WLAN用户室内室外定位技术方案。  相似文献   

8.
肖颖 《物联网技术》2012,(6):23-24,27
RFID是一种非接触式自动识别技术,它的应用非常广泛。SpotON系统、LANDMARC系统都是基于RFID的无线定位系统。文章介绍了RFID用于室内定位的4种不同的定位模式,同时介绍了采用RFID技术来简化对WLAN基础设施进行管理的思科无线定位解决方案。该解决方案可从WLAN基础设施内部跟踪数千个无线设备,从而简化WLAN管理,有效提高网络扩展性。  相似文献   

9.
彭丹 《福建电脑》2006,(8):48-49
无线局域网是指以无线信道作传输媒介的计算机局域网络(Wireless Local Area Network,简称WLAN),是在有线网的基础上发展起来的,使网上的计算机具有可移动性,能快速、方便地解决有线方式不易实现的网络信道的连通问题.文章就无线局域网的特点、技术实现、安全性、国际标准、组网方式进行了阐述.  相似文献   

10.
无线局域网络(Wireless Local Area Networks,WLAN)是相当便利的数据传输系统,它利用射频(Radio Frequency,RF)的技术取代旧式双绞铜线构成局域网络,使得用户可以在它覆盖的几百米范围内使用无线设备自由移动。其使用及其方便且价格便宜,但由于无线局域网具有很大的开放性,其面临着更严峻的安全问题。该文在阐述无线局域网安全发展概况的基础上,分析了无线局域网的安全必要性,并从不同方面总结了无线局域网遇到的安全风险,同时重点分析了IEEE802.11b标准的安全性、影响因素及其解决方案,最后对无线局域网的安全技术发展趋势进行了展望。  相似文献   

11.
随着WLAN在室内环境的日益普及,基于现代的移动设备可以方便实时地获取各种有价值的WLAN数据,这对我们识别个体日常生活中的多样化行为提供了前所未有的机会。近年来,用户的兴趣点与行为模式挖掘等领域日益引起各界的广泛关注,设计了一套基于室内定位的推荐系统,基于用户的历史访问记录,实现从过载的信息中识别出用户感兴趣的内容。现有的位置服务通常只针对用户的室外位置数据,缺乏对室内数据的挖掘分析,忽略了室内位置数据中蕴含的大量语义信息。利用室内定位技术获取用户在商场中的活动轨迹,根据用户去过的店铺和浏览过的商品等历史信息,估算用户的兴趣爱好并进而向用户个性化地推荐感兴趣的商品,基于以上思路设计实现了一套基于室内定位和微信平台的个性化商品推荐系统。  相似文献   

12.
Location-based services (LBSs) have long been identified as an important component of emerging mobile services. While outdoor positioning has become strongly established, systems dealing with indoor positioning in urban environment are still under development. The upcoming LBSs require positioning systems (PSs) that are available ubiquitously, which requires the integration of the PS available in an outdoor environment with the PS available in indoor environment. Global navigation satellite systems (GNSSs) such as GPS, GLONASS, Galileo, and QZSS are some of the prominent systems that provide outdoor positioning. Indoor positioning systems (IPSs), however, are undergoing rapid development, and these systems can be supplied using short-range wireless technologies such as Wi-Fi, Bluetooth, RFID, and Infrared. Among these technologies, intense research is being conducted into Wi-Fi-based positioning systems due to their ubiquitous presence. This paper presents a model and results for a ubiquitous positioning system (UPS) that integrates a novel WLAN-based IPS and GNSS. The IPS is developed using cascading artificial neural networks, which are further optimized using genetic algorithms. The systems were thoroughly investigated on an actual Wi-Fi network at Asian Institute of Technology, Thailand. The IPS demonstrated a mean accuracy of 2.10 m and the UPS demonstrated a mean accuracy of 3.26 m, with 89% of the distance error within the range of 0–3.5 m.  相似文献   

13.
一种基于BP神经网络的室内定位模型   总被引:1,自引:0,他引:1  
室内定位技术是一种获取室内的人和物位置信息的技术,以位置信息为基础可为使用者提供多种服务,在军事和民用领域都有着广阔的应用前景.在分析几种常见的室内无线定位方法以及基于RSS的室内无线定位方法的基础上,提出一种基于BP神经网络的室内定位模型并借助MATLAB 7.0加以实现.采用该方法进行室内定位,不需要WLAN以外的其他资源.由于不需要知道定位节点和建筑物的详细特性,用户的隐私将会得到完全的保护.仿真实验证明该模型的有效性.  相似文献   

14.
In the last years, an increasing interest in location services characterized the market of mobile ubiquitous devices (smartphones, handhelds, etc.). Several technologies and solutions have been developed to determine the position of mobile devices in their operating space, each with its specific degree of precision and accuracy. In this scenario, the ideal location service should be able of tracking the mobile terminal in any place it moves to, both indoors and outdoors. However, while outdoor location services have already achieved a satisfactory degree of technological maturity and effectiveness, a really ubiquitous location service that works satisfactorily in both indoor and outdoor scenarios is not yet available. In order to cope with the above challenge, this work proposes a hybrid location approach designed to choose and switch among multiple positioning technologies supported by the mobile device and available in the surrounding environment, in a dynamic and transparent way during the user movement. It combines signal strength–based fingerprinting techniques for indoor positioning together with traditional GPS-based positioning for the outdoor localization and performs opportunistic technology switching according to a count-and-threshold mechanism. The resulting solution is able to leverage the different features of the wireless networks and of the global positioning technologies, in order to provide ubiquitous location services across indoor and outdoor scenarios, as well as to minimize power consumption of the mobile device.  相似文献   

15.
Due to the popularity of location-based services, determining the location of a device at all times has become a subject of great interests. Although many GPS-based applications have been developed and successfully deployed in various fields, their applicabilities are hindered by the obstruction of the objects in the environment. Essentially, as satellite signals cannot penetrate the walls of buildings, the coverage of GPS systems is limited to outdoor environments. To fully exploit the benefit of location-based services, approaches that determine the location of a device in indoor environments need to be established. This study presents a novel location determination mechanism that uses an indoor WLAN and back-propagation neural network (BPN). A museum is taken as the context of the example indoor environment. Location determination is achieved using the combined strengths of 802.11b wireless access signals. With a significant number of access points (APs) installed in the museum, hand-held devices can sense the strengths of the signals from all APs to which the devices can connect. Using a back-propagation network, device locations can be estimated with sufficient accuracy. A novel adaptive algorithm is implemented for enhancing the accuracy of the estimation.
Shuo-Yan ChouEmail:
  相似文献   

16.
Location Based Service (LBS) cannot be realized unless the location of the user is available. For indoor LBS, indoor positioning must be utilized and many researchers have been working on indoor positioning and tracking. For example, Extended Kalman filter (EKF) was exploited in Bluetooth based indoor positioning. Nowadays, WLAN (Wireless Local Area Network) is available virtually everywhere. Thus, WLAN based indoor positioning and tracking is more economical than Bluetooth based ones. This paper proposes a new WLAN based EKF indoor tracking method by extending existing Bluetooth based EKF positioning method. After analyzing the experimental results of it, we modified it to use K-NN method in the measurement stage of it. Then we propose to further improve the accuracy of indoor tracking by adjusting the parameter values referring to the map information. Experimental results comparing our method with other previous methods are discussed.  相似文献   

17.
Personal task reminders have been indispensable for modern people, in order to remind them of their tasks at specific circumstances. Traditional paper-based reminders are still useful, but they cannot be organized efficiently. Electronic reminders based on the calendar in cell phones are more efficient and gaining popularity, but such reminders are mostly triggered by time. In many situations, tasks are only meaningful to be performed at a specific location, so it would be useful if reminders for those tasks can be triggered only when the person to be reminded is physically near or located at that location. Therefore, in this research, we develop a location-based personal task reminder for Android-based smartphones and tablets. To distinguish our work from existing ones that rely solely on the GPS technology, we take advantage of the ubiquity of IEEE 802.11 WLAN infrastructure to compliment the “blind spots” of GPS location sensing. Combining the two technologies makes it possible for the personal task reminder to be effective in both indoor and outdoor environments. We also propose two operating models for the personal task reminder to boost the usability of the application. Furthermore, as long as the WLAN infrastructure is available, our work as a foundation of location-based services can easily be extended to be used in many other scenarios, such as guiding in public transportation systems or tourist attractions, location-based learning, and even caring of the Dementia residents.  相似文献   

18.
目前,WLAN的主要建设模式以室内独立放装和室分系统合路方式为主,室外广域覆盖模式应用策略不明确,规划建设不是很成熟。对WLAN广域覆盖存在的问题和解决思路进行了研究,并进行了大量的测试工作,对测试结果进行了深入分析,最终给出了WLAN广域覆盖的应用建议。  相似文献   

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