• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.6B
• /
• pp.544-552
• /
• 2003

This paper suggests an instruction code sufficiency algorithm preventing data collision when multiple transponders attempt to connect in the radio frequency identification system. Conventional time domain procedure generates unconditional collision. On the other hand, this algorithm prevents data collision by transmitting data when it meets instruction code. When multiple transponders are transmitting data coincidently, they exploit desired data with using difference of arrival time generated by recognition distance, respectively. As a result of simulation, utilizing the wireless recognition system, adopting the suggested algorithm, operating in 13.56MHz frequency band, it verify that there is Anti-collision and data loss by ensuring transmission time difference of one bit by adopting this algorithm.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.1
• /
• pp.56-62
• /
• 2011

A Satellite transponder is mounted on the Satellite and performs radio communications with the ground station. A Digital transponder compared to The analog transponder is made easy and accurate performance prediction. Also Modulation Scheme, Data Rate, Loop Bandwidth, Modulation Index and etc. can be changed on orbit, by implementing FPGA can reduce the weight and volume. The core technology of digital transponder is Carrier Recovery loop. Dynamic Range, Frequency Tracking Range, Frequency Tracking Rate and Coherent performance are determined by the performance of the Carrier Recovery loop. In this paper, we proposed the structure of Carrier Recovery loop for the Satellite digital transponder, then tested and verified the structure.

• Journal of the Korean Society for Railway
• /
• v.20 no.5
• /
• pp.602-611
• /
• 2017

In railway systems, the exchange of information between running trains and wayside equipment is a very important role in various applications such as position detection and train control. Track circuits have been used as the medium for information transmission between trains and wayside. However, track circuits must be installed continuously along the track on the ground, resulting in an inevitable increase in installation and maintenance costs. One of the most promising solutions to reduce these costs is to mix continuous information transmission (via wireless communication) and discontinuous information transmission (via transponder). In this study, we designed antennas of railway high-speed transponder readers and tags for wireless power transmission, which can be used to transmit information from ground to high-speed trains with a maximum speed of 400km/h. We also verified system performance through computational simulation and prototyping.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.21 no.5
• /
• pp.494-500
• /
• 2010

In this paper, we newly propose a wireless optical identification system and carried out experiments. A wireless optical identification system consists of a reader and a transponder. The configuration of a reader is the same as that of a transponder, which uses LED light as transmission media and detects the signal light with a solar cell. Optical alignment with a lens is not required because the absorption area of a solar cell is wide and flat, and it is very easy to attach a solar cell on the surface of an object. As the light wavelength does not interfere with radio frequency, a wireless optical identification system shows stable operation. In experiments, we realized a wireless optical identification system that automatically identifies the transponder data at a distance of 1 m using solar cells.

• Proceedings of the KIEE Conference
• /
• 2005.11b
• /
• pp.195-197
• /
• 2005

본 논문에서는 트랜스폰더와 리더를 이용한 무선 데이터 통신 모듈의 개발에 관하여 논하였다. 이 모듈의 제작에 있어 필요한 일련의 사항들을 살펴보고 신뢰성 있는 통신을 위해 프로토콜을 적용하였다. 통신거리개선을 위해 전력증폭기 시뮬레이션, 안테나 임피던스 매칭에 관한 연구를 해 보았다.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2006.11a
• /
• pp.511-514
• /
• 2006

Material Management is one of the most important task in construction projects. More than 50% of the cost in a construction project is related to material management process. Material management method using RFID(Radio Frequency Identification) is now trying to the construction field. However, there are no enough researches on effective material management in terms of how and where RFID transponder should be installed and there are no other research that which optimization method can be used for effective installation. Therefore, this paper suggest that where and how RFID transponder can be installed on the appropriate position in construction fields using Genetic Algorithm optimization method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.61-65
• /
• 2003

In this paper, we analysed the standardized techniques for radio frequency identification systems. RFID system is to carry data in suitable transponders, generally known as tags, and to retrieve data, by machinable means, at a suitable time and place to satisfy particular application needs. The paper has discussed on international standardization trends and its techniques and provided with understanding the technical regulations for activating and harmonizing internationally domestic RFID industries.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.8 no.3
• /
• pp.232-242
• /
• 1997

In this paper, we have designed an active radio frequency identification system solving the problems of moving transponder which is identification range expanding and low battery consuming of transponder. Developed radio frequency identification system is a bidirectional data transmission system which is composed of decoder data transmission of 120 kHz and transponder data carrier of 60 kHz which is a subharmonic frequency response with ASK modulation. The experimental results, designed system operating at 9600 bps, show good performances with detecting the 40 km/h moving transponder up to the range of 2 and 15 ${mu}A$ low consuming current.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.6
• /
• pp.9-15
• /
• 2020

In this paper, we propose a case that drone (unmanned aerial vehicle), one of the representative technologies of the 4th Industrial Revolution, threatens airport safety and privacy infringement, and describes a drone control system proposal to solve the problem. Unmanned aerial vehicle (Drone) is creating a serious problem recently, In Korea, on May 21, 19, according to the Jeju Regional Aviation Administration, drones flew over Jeju Jeongseok Airfield twice in the same month, causing problems in aircraft operation. In overseas cases, two drones near the runway of Gatwick International Airport in the UK There has been a disturbance in which the takeoff and landing of the aircraft flies for a while, and various problems have occurred, such as voyeuring the private life of an individual using a drone. This paper is equipped with an Acess Point transponder mounted on a drone (unmanned aerial vehicle), and unspecified many who want to receive flight information (coordinates, altitude, and obstacles) of the drone access the drone AP, receive and receive the flight information of the drone, and receive unspecified multiple Drone AP flight information is collected and collected to provide the information of the drone currently floating on one user interface screen. In addition, an AP transponder is proposed to operate a safe drone (unmanned aerial vehicle) and the drone's flight information is transmitted., To receive and collect and collect data.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.6
• /
• pp.1055-1059
• /
• 2004

A RFID(Radio Frequency Identification) system is a kind of radio frequency communication system and a branch of automatic data collection system. RFID system consists of RFID tags(or transponders) and RFID readers(controllers). This paper deals with the wireless communication that acquires tag IDs through RFID readers, and show the implementation of the target system which transmits tag IDs and related information to the server on the Internet through the wireless local area network. Today's RFID systems are usually implemented with the wired communication environment. In this paper, however, RFID system is effectively realized with the widely deployed wireless local area network and various RFID data can be collected by the readers which are communicating with the wireless access points of the local area network. Through the Internet, users also can have easy access to the server on the web and retrieve, analyze, and utilize tags' information.