• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.4
• /
• pp.1005-1014
• /
• 2010

When reader collect tags, we found that they tend to get together to specific interface in Multi-Interface Multi-Channel 2.4GHz Active RFID system. To solve this problem, we designed the LP-Combind and AP-Balanced protocol for load distribution between interfaces, then verified its superiority of the performance through the simulation. There are three problems to implement designed protocols in hardware of firmware-level. first, tag selects randomly the channel of reader and reader need the method which can change the channel of tags. second, reader has the synchronization problem between reader and tag. third, reader has problem that MCU of reader have to operate simultaneously dual interface. To slove this problems, we designed the message and implemented method for tag channel change and the protocol in order to adjust synchronization between reader and tag, Therefore, we compared and analyzed the performance of protocols by experiment. If LP windows size is same, the performance of LP-Combined protocol and AP-Balanced protocol which lower collision probability by its load distribution is more outstanding than single interface protocol performance.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.5
• /
• pp.871-885
• /
• 2015

The improved DFSA for 2.4GHz multi-tags active RFID is suggested in 2 different ways: 1) simplified tag collection and Ack procedure using query command and 2) modified Schoute's method to control the number of slots in the frame. To evaluate the performance of the improved system we develop the simulation model. Varying the number of tags in the system we track the performance measures such as throughput, recognition time for multi-tags and tag recognition rate during a given time. The suggested method shows the best performance over all measures. Simplification of collection and Ack commands using query commands contributes to reducing tag recognition time. And the modified Schoute's method which controls the frame size using $k_1$ and $k_2$ contributes to throughput improvement and reduces target cognition time by reducing the number of collection rounds.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38B no.3
• /
• pp.199-206
• /
• 2013

This paper proposes a modified tag collection algorithm that improves the drawback of the identified slot scan-based tag collection algorithm presented in a previous paper to improve the tag collection performance in active RFID systems. The previous identified slot scan-based tag collection algorithm is optimized in situations where all the tags store the fixed size of data, so it could not result in a good performance improvement with tags having the variable size of data. The improved tag collection algorithm proposed in this paper first collects the slot size information required for the data transmission from each tag via the identified slot scan phase, and then performs the tag collection phase using the information, which resolves the problem of the previous identified slot scan-based tag collection algorithm. The simulation results for performance evaluation showed that the proposed tag collection algorithm resulted in the almost same tag collection performance as the previous algorithm when all the tags have the same size of data and led a large improvement of the tag collection performance in ISO/IEC 18000-7 unlike the previous algorithm when each tag has a random size of data.

• IEIE Transactions on Smart Processing and Computing
• /
• v.1 no.1
• /
• pp.65-71
• /
• 2012

Mobile RFID is a new application that uses a mobile phone as an RFID reader with wireless technology and provides a new valuable service to users by integrating RFID and ubiquitous sensor network infrastructures with mobile communication and wireless Internet. Whereas the mobile RFID system has many advantages, privacy violation problems on the reader side are very concerning to individuals and researchers. Unlike in regular RFID environments, where the communication channel between the server and reader is assumed to be secure, the communication channel between the backend server and the RFID reader in the mobile RFID system is not assumed to be safe. Therefore it has become necessary to devise a new communication protocol that secures the privacy of mobile RFID-enabled devices. Recently, Lo et al. proposed a mutual key agreement protocol that secures the authenticity and privacy of engaged mobile RFID readers by constructing a secure session key between the reader and server. However, this paper shows that this protocol does not meet all of the necessary security requirements. Therefore we developed an enhanced mutual key agreement protocol for mobile RFID-enabled devices that alleviates these concerns. We further show that our protocol can enhance data security and provide privacy protection for the reader in an unsecured mobile RFID environment, even in the presence of an active adversary.

• Journal of information and communication convergence engineering
• /
• v.5 no.4
• /
• pp.369-373
• /
• 2007

RFID systems large volume of data, it can lead to slower queries. To achieve better query performance, we can partition into active and some nonactive data. In this paper, we propose two approaches of partitioning for efficient query support. The one is average period plus delta partition and the other is adaptive average period partition. We also present the system architecture to manage active data and non-active data and logical database schema. The data manager check the active partition and move all objects from the active store to an archive store associated with an average period plus data and an adaptive average period. Our experiments show the performance of our partitioning methods.

• Journal of the Korea Safety Management & Science
• /
• v.10 no.2
• /
• pp.169-174
• /
• 2008

In this study we develop core technology of Multi-Charmel Voice Guidance System based on active 2.45GHz RFID that can be used in the field of advertising. Through this, we can service more familiar with voice information to foreigners by own language in large scale international event. As an alternative to the current high-expensive voice guidance system in exhibition hall and provide more value added services to user. As the result, we present the configuration of integrated software platform which include media server, media client and receiver. It can be as a basis infra equipment for a signtseeing in RFID/USN environment. Additionally through tag information analysis about exposure of advertisement that is collected late, supposed system may achieve role as a new marketing tool.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.11 no.1 s.22
• /
• pp.39-45
• /
• 2005

Recently, RFID technology play a key role to implement ubiquitous sensor network(USN). In this paper, we introduce trends of RFID technology, standardization, and then its applications. The purpose of this work is to suggest prosperous applications of RFID, which is applicable on marine information system, such as ship inventory management, management of container and its contents, sensing of environments within cargo hold, management of fishery boats. In case that RFID technology is utilized on marine information systems, it makes safety at sea and marine environments protection.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2006.05a
• /
• pp.549-552
• /
• 2006

Radio Frequency Identification(RFID)는 유비쿼터스 환경에서 주목받고 있는 기술이다. 이러한 RFID 미들웨어 시스템을 구축하는데 하드웨어 구축비용뿐만 아니라 소프트웨어 개발 비용도 매우 크다. 그러나, 이미 대중화 된, 상대적으로 개발비용이 매우 저렴한 웹 미들웨어 시스템에 RFID 시스템을 적용을 시킨다면, 그 파급 효과는 매우 클 것이다. 따라서 본 논문에서는 웹페이지와 RFID의 데이터 교환을 위해 ActiveX를 어떻게 이용하였는지를 살펴보고, 또한 RFID를 웹 환경의 미들웨어 시스템에 실제 적용하여 봄으로써 그 가능성을 논의해보고자 한다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.12A
• /
• pp.1238-1245
• /
• 2006

Interest to the RTLS that is one of RFID applications is increasing in recent. The RTLS(Real Time Locating Systems) is one of applications for locating and tracking using RFID tags which are attached to something like container, pallet, or all the things. This paper presents the design and the implementation of an RTLS system using 433MHz active RFID tags and use radio frequency to provide the scalability. Our system we developed using RFID platform takes into account an RTLS standard. Also, in this paper a routing protocol is included to data delivery to server via each reader. In order to perform the evaluation, in addition, some experiments in out door are performed and results such as error metric and distance are also included. Furthermore, simulation for the routing protocol we supposed is also included.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.1C
• /
• pp.24-33
• /
• 2012

Recently, the ultra-lightweight authentication RFID protocol that can actually implement on the RFID Tag is one among authentication protocols getting a concern, but recently many problems were clarified of the feature becase of the protocol which doesn't use the security algorithm. In this paper, we analyzed the problem of the ultra-lightweight authentication protocols and propose the design of ultra-lightweight RFID authentic ation protocols improving the index processing techniques. Because of improving the index processing technique in the method sending the Server authentication message to the authenticated tag, the proposed protocol is strong against the active attack which Li presents. Besides, the proposed protocol has the buffer storage of the keys and index and is strong against the asynchronous attack.