汽车数字化标准信源系统识读距离仿真

为实现汽车数字化标准信源系统的采集基站建设和标签安装的最优配置,对无源射频识别（RFID）车辆身份管理系统的识读距离进行了仿真计算。在读写器天线与标签天线远场图确定的条件下,对采集基站的架设参数,例如天线的安装倾角,仿真计算得到目标车辆通过固定式龙门架无源RFID采集基站时的可识读距离,并进行比较分析。为汽车数字化标准信源系统不同车型的标签安装位置以及采集基站的架设提供了参考依据。     

RFID-Based Positioning System for Telematics Location-Aware Applications

Positioning accuracy is an essential factor for many location-aware applications. This study designs an RFID-based positioning system for telematics location-aware applications. If a passenger in a vehicle loses a wallet with an RFID tag attached, then an RFID reader can be adopted to detect the tag, and thus find the wallet. Performance analysis results indicate that the proposed RFID-based positioning system has a distance error of less than 1.64 m, and an accuracy rate at least 13.24% higher than the common LANDMARC approach. These results indicate that the RFID operations in telematics positioning applications have high-accuracy location-awareness.     

An adaptive location estimator using tracking algorithms for indoor WLANs

This paper presents adaptive algorithms for estimating the location of a mobile terminal (MT) based on radio propagation modeling (RPM), Kalman filtering (KF), and radio-frequency identification (RFID) assisting for indoor wireless local area networks (WLANs). The location of the MT of the extended KF positioning algorithm is extracted from the constant-speed trajectory and the radio propagation model. The observation information of the KF tracker is extracted from the empirical and RPM positioning methods. Specifically, a sensor-assisted method employs an RFID system to adapt the sequential selection cluster algorithm. As compared with the empirical method, not only can the RPM algorithm reduce the number of training data points and perform on-line calibration in the signal space, but the RPM and KF algorithms can alleviate the problem of aliasing. In addition, the KF tracker with the RFID-assisted scheme can calibrate the location estimation and improve the corner effect. Experimental results demonstrate that the proposed location-tracking algorithm using KF with the RFID-assisted scheme can achieve a high degree of location accuracy (i.e., more than 90% of the estimated positions have error distances of less than 2.1 m).     

车联网移动无线数据通信系统的设计与实现

为了提高车联网移动无线数据通信能力,实现通过无线数据通信系统对车辆监控与导航,利用RFID和GPS技术,通过对车联网无线数据通信系统的结构分析,设计了车联网移动无线数据通信系统。重点研究了车载终端总体结构、车载终端通信模块、RFID感知通信模块、移动通信平台架构、定位追踪通信模块和远程控制通信模块。应用结果表明,该移动无线数据通信系统有较好显示能力和信息处理能力,能够处理导航、信息服务、车辆信息显示与辅助控制等功能的车载终端信息通信服务的需求。     

The Optimal Traffic Information Process System by Using MIMO Algorithm

This paper presented dynamic vehicle information for wireless communication and safe systems by integrating radio frequency identification (RFID) technology. The systems provied different particular and advantage between RFID and other recognition technology. The car black box is the best choice and innovates specific application. It is not only the system can guard car but differentiate the responsibility for car accident event. Furthermore, the car black box is integrated the RFID, general packet radio service (GPRS), Bluetooth, personal digital assistant (PDA) and global positioning system (GPS). The proposed system has been trending the merger goal of digitization. Therefore, it is created a tremendous amount of commercial opportunity. The car black box is also combined multiple-user with real-time navigation information system. The system is integrated the independent real-time traffic information database and Geographical Information System (GIS) through data fusion method. We adopted a traffic information system offering advanced personalized route planning, including added services for traffic jam alerting by means of Short Message Service (SMS) in Global System for Mobile (GSM) communication network. It is shown small and low-cost GSM modules for data process by using the Multiple Input Multiple Output (MIMO), Ant colony optimization (ACO) algorithm, which developed a real-time software solution to help users and evaluation of user preferences for car traffic information system.     

Position Tracking for Passive UHF RFID Tags with the Aid of a Scanned Array

Thanks to the proliferation of radio frequency identification systems (RFID), applications have emerged concerning positioning techniques for inexpensive passive RFID tags. The most accurate approaches for tracking the tag’s position, deliver precision in the order of 20 cm over a range of a few meters and require moving parts in a predefined pattern (mechanical antenna steering), which limits their application. Herein, we introduce an RFID tag positioning system that utilizes an active electronically-steered array, based on the principles of modern radar systems. We thoroughly examine and present the main attributes of the system with the aid of an finite element method simulation model and investigate the system performance with far-field tests. The demonstrated positioning precision of 1.5°, which translates to under 1 cm laterally for a range of a few meters can be helpful in applications like mobile robot localization and the automated handling of packaged goods.     

室内激光雷达导航系统设计

小型无人机和移动机器人技术迅速发展,对室内导航技术的要求越来越高,针对当前室内导航精度不高、导航设备比较复杂的问题,提出一种采用激光雷达定位和地磁传感器检测相结合的室内主动导航方法。该方法首先使用激光雷达扫描室内环境,用采集到的数据拟合出室内地图,根据目的地信息和室内的环境信息来规划行进的路线;然后在行进中使用激光雷达连续地扫描得到数据与地图数据进行比较,来确定所处的位置,同时使用地磁传感器取得行驶的方向,二者相结合判断是否在规划的路线上行驶,及时地对出现的偏差进行纠正;最后通过搜索RFID地标确定是否已经到达指定位置。仿真和实验的结果表明:所设计的室内激光雷达导航系统结构简单、可靠性高,能够较好地满足室内导航的要求。     

基于相互认证的移动RFID安全协议

移动RFID系统是指利用植入RFID读写芯片的智能移动终端,获取标签中的信息,并通过移动网络,访问后台数据库,获取相关信息。然而,由于移动RFID系统的无线通信环境和无可视性读写,带来了很多安全隐患,已经成为制约移动RFID发展的重要因素,针对此问题,在分析了移动RFID网络构成及其安全隐患后,提出了一种基于相互认证的安全协议,该协议引入了一个第3方服务器来为移动读写器和后台数据库提供签名密钥,并且利用椭圆曲线加密体制(ECC)对信息进行签名验证,最后分析表明该协议可以为移动读写器与后台数据库提供安全的通信环境,以应对各种攻击。     

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。      

一种基于无源射频识别标签的消防员室内定位系统

消防员在地下建筑、无窗建筑、大型建筑物内,执行火情控制与人员搜救时,不可避免会遇到浓烟、黑暗、高温、陌生等情况,因此就需要精确的室内定位系统支持,已有的室内定位技术无法满足定位精度和长期部署的需求.本文提出了一种基于无源射频识别（RFID）标签的消防员室内定位系统,通过在消防员头盔内安装可变功率的RFID读写器,并将建筑物内读取的已经过精确标定的RFID标签信息回传到远程服务器进行计算处理,可实现建筑物外指挥员对室内消防员的实时精准定位和指挥功能.     

Integrating RFID and WLAN for indoor positioning and IP movement detection

Location awareness in an indoor environment and wireless access to Internet applications are major research areas towards the overwhelming success of wireless and mobile communications. However, the unpredictable indoor radio propagation and handover latency due to node mobility are the main challenging issues that need to be addressed. For tackling efficiently both problems of indoor localization and handover management, we propose combining key benefits of two outstanding wireless technologies, i.e. radio frequency identification (RFID) and a wireless local area network (WLAN) infrastructure. WLANs, such as IEEE 802.11 (WiFi), are now very common in many indoor environments for providing wireless communication among WiFi-enabled devices by accessing an Access Point (infrastructure mode) or through peer to peer connections (ad hoc mode). However, the small cell size of the Access Points (APs) in a WiFi-based network drives the need for frequent handovers leading to increased latency. RFID is an emerging technology consisting of two basic components, a tag and a reader, and its main purpose is the automatic identification of tagged objects by a reader. However, in the presence of multiple readers, RFID suffers from the so-called reader collision problem, mainly due to the inability for direct communication among them. In this paper, we propose a hybrid RFID and WLAN system; the RFID technology is employed for collecting information that is used for both localization and handover management within the WLAN, whereas the WLAN itself is utilized for controlling and coordinating the RFID reading process. In our system architecture, tag IDs of a RFID tag deployment are correlated with both location and topology information in order to determine the position and predict the next subnetwork of a Mobile Node (MN) with a reader attached to its mobile device. The role of the WLAN is to coordinate the readers when accessing the RFID channel for retrieving tags?? IDs, hence compensating the persisting RFID collision problem among multiple readers. Numerical results based on extensive simulations validate the efficiency of the proposed hybrid system in providing accurate and time efficient localization and reducing the IP handover latency.     

基于差分进化算法的RFID定位

针对传统射频识别(RFID)定位过程繁琐,系统定位精确度低以及计算较为复杂的问题,提出一种利用差分进化(DE)算法优化RFID定位精确度的方法。该方法首先随机初始参考标签的位置坐标,通过接收信号强度(RSS)值计算出阅读器与标签之间的测量距离,再通过优化阅读器与参考标签和待测标签之间的距离误差,估计出离待测标签最近的位置坐标,最后与经典LANDMARC定位系统做比较。仿真结果表明,经典LANDMARC定位系统的平均定位误差为1.115 8 m,而利用差分进化算法优化后的系统平均定位误差为0.001 2 m,从而证明利用差分进化算法优化RFID定位的方法是有效的。     

Hardware implementation of tag-reader mutual authentication protocol for RFID systems

Radio-frequency identification (RFID) is a recent technology that utilizes radio frequencies to track the object by transmitting a signal with a unique serial identity. Generally, the drawbacks of RFID technology are high cost and authentication systems between a reader and a tag become weak. In this paper, we proposed a protocol for RFID tag–reader mutual authentication scheme which is hardware efficient and consumes less dynamic power. Truncated multipliers are implemented in RFID tag–reader mutual authentication protocol system due to reduction in hardware cost and dynamic power. Experimental evaluation reveals that the proposed protocol with truncated multipliers provides more security than the earlier schemes. The proposed protocol is described in VHDL and simulated using Altera Quartus II. The functional block is implemented as hardware using an Altera DE2 Cyclone II (EP2C35F672C6) Field-Programmable Gate Array (FPGA).     

Intelligent location models for next generation location-based services

To become truly ubiquitous, next generation location-based services (LBS) will have to rely on mobile platforms upon which multiple sensors and measurement systems have been integrated to provide continuous, three-dimensional positioning and orientation. Such technologies are explored today for example in mobile mapping systems, vehicle navigation systems and mobile robot navigation. Next-generation LBS also need theoretically sound methods to translate position into location information. The article addresses this problem: the transformation of position into meaningful and reliable location, and the transformation of location knowledge into positioning constraints. It suggests by this way an intelligent location model that integrates sensor fusion with spatial knowledge fusion via a feedback cycle. It is shown that this feedback cycle consists of three layers: spatial constraints, temporal constraints and spatiotemporal constraints.     

RFID-based localization with Non-Blocking tag scanning

The simple and cheap passive RFID tag systems have recently been used for efficient localization of indoor mobile robots, where each RFID tag stores its own absolute position and the mobile robot carrying an RFID reader scans the RFID tags to localize itself. The available localization schemes using passive RFID systems do not consider the scanning delay which may cause location estimation error, especially when the robot moves at a high speed. In this paper, a new Non-Blocking scanning (reading) scheme is proposed to avoid collisions so that the scanning delay, and consequently the localization error, can be reduced. This scheme avoids collisions among tag replies by assigning tag IDs based on the FCA coloring scheme. Theoretical and simulation studies indicate that the new Non-Blocking scheme combined with the new tag arrangement pattern can achieve a good RFID localization performance in terms of both estimation error and scanning delay with reduction of tag/reader required complexities.     

RFID系统中停留标签的组策略防碰撞算法

在射频识别RFID系统中,防碰撞算法对于标签的快速识别,尤其在移动应用的场景中非常重要。该文针对移动场景中停留标签,提出了组策略停留标签算法GSRA(Group Strategy for Remaining tags Algorithm),分为停留标签识别和新到标签识别两个阶段,并将停留标签信息分组存放与更新,从而提高停留标签的识别效率。理论分析证明该算法系统效率仅与标签动态时移动时的迁移速率和静态时的系统效率有关,而与标签数量无关。仿真结果表明GSRA算法在标签迁移速率为20%时,结合冲突树算法CT,系统效率可以达到240%。     

A hidden mutual authentication protocol for low‐cost RFID tags

Radio‐frequency identification (RFID) technology enables the identification and tracking of objects by means of the wireless signals emitted by a tag attached to the objects of interest. Without adequate protection, however, malicious attackers can easily eavesdrop, scan or forge the information within the tag, thereby threatening the integrity of the system. Previous research has shown that the basic security requirements of RFID systems, i.e. identity authentication, information privacy and location privacy, can be satisfied using conventional cryptographic components. However, such components are expensive, and therefore conflict with the general requirement for low‐cost tag designs. Accordingly, this paper presents a low‐cost challenge‐response security protocol designated as the hidden mutual authentication protocol (HMAP) to accomplish both a mutual authentication capability between the tag and the reader and information privacy. The results show that HMAP provides an efficient means of concealing the authentication messages exchanged between the tag and the reader and is robust toward replay attacks. In addition, it is shown that HMAP is easily extended to provide complete location privacy by utilizing a hash function to generate different tag identifiers in each authentication session. Copyright © 2011 John Wiley & Sons, Ltd.     

可证明安全的RFID标签所有权转移协议

随着物品所有权的转移,其上附着的RFID标签的所有权也需要转移。安全和隐私问题是标签所有权转移过程中需要研究的重点问题。在通用可组合框架下,形式化定义了RFID标签所有权转移的理想函数。提出了一个新的轻量级RFID标签所有权转移协议,并证明了该协议安全地实现了所定义的理想函数,即具有双向认证、标签匿名性、抗异步攻击、后向隐私保护和前向隐私保护等安全属性。与已有的RFID标签所有权转移协议相比,新协议中RFID标签的计算复杂度和存储空间需求都较低,并且与新旧所有者的交互较少,能够更加高效地实现低成本标签的所有权转移。     

ASAF ALOHA Protocol for Dense RFID Systems

RFID tags are used for varied applications in large numbers. Human Tracking is one such important application wherein the RFID system detects the presence of a tag in a dense tag environment. Quick estimation of the number of tags in the field at a desired level of accuracy is one of the most common requirements in the present scenario. Identification of tags has become a critical area which need more time and unsuitable in many situations; especially where tag set is dense. We introduce a novel medium access control (MAC) protocol for Radio Frequency IDentification (RFID) systems which exploits the statistical information collected at the reader. The protocol, termed Adaptive Slot Adaptive Frame (ASAF) ALOHA protocol, is motivated to significantly improve the total read time performance of the currently suggested MAC protocols for RFID systems by minimizing the collisions of the tags. In order to perform this task, ASAF estimates the dynamic tag population and adapts the frame size and number of slots simultaneously in the subsequent round via a simple policy that maximizes an appropriately defined function. We demonstrated that ASAF is better than the current RFID MAC protocols. We also considered the case where suddenly if the number of tags increases, the running frame with adapted slots gets flushed away and new frame with increased number of slots gets adapted automatically by the system showing the robustness in this case as well.     

A practical quadratic residues based scheme for authentication and privacy in mobile RFID systems

In this paper we propose a novel approach to authentication and privacy in mobile RFID systems based on quadratic residues and in conformance to EPC Class-1 Gen-2 specifications. Recently, Chen et al. (2008) [10] and Yeh et al. (2011) [11] have both proposed authentication schemes for RFID systems based on quadratic residues. However, these schemes are not suitable for implementation on low-cost passive RFID tags as they require the implementation of hash functions on the tags. Consequently, both of these current methods do not conform to the EPC Class-1 Gen-2 standard for passive RFID tags which from a security perspective requires tags to only implement cyclic redundancy checks (CRC) and pseudo-random number generators (PRNG) leaving about 2.5k–5k gates available for any other security operations. Further, due to secure channel assumptions both schemes are not suited for mobile/wireless reader applications. We present the collaborative authentication scheme suitable for mobile/wireless reader RFID systems where the security of the server–reader channel cannot be guaranteed. Our schemes achieves authentication of the tag, reader and back-end server in the RFID system and protects the privacy of the communication without the need for tags to implement expensive hash functions. Our scheme is the first quadratic residues based scheme to achieve compliance to EPC Class-1 Gen-2 specifications. Through detailed security analysis we show that the collaborative authentication scheme achieves the required security properties of tag anonymity, reader anonymity, reader privacy, tag untraceability and forward secrecy. In addition, it is resistant to replay, impersonation and desynchronisation attacks. We also show through strand space analysis that the proposed approach achieves the required properties of agreement, originality and secrecy between the tag and the server.