• The Journal of the Korea Contents Association
• /
• v.7 no.11
• /
• pp.102-110
• /
• 2007

In this paper, a portable RFID reader which operated in 900MHz UHF band is designed and fabricated and the characteristics of the manufactured portable RFID reader is analyzed through measurement. Analysis of measurements results is achieved based on EPC Class 0 standards that proposed by EPC Global. The proposed RFID reader communicate with tags about 11kbps speed, and have 20 dBm for its maximum RF output power. The proposed portable RFID reader can recognize maximum 68 tags per second, and when reader's output power is 20 dBms, maximum recognition distance is 30cm. And the total size of implemented RFID reader is $71mm{\times}55mm$, that is the maximum 90%, minimum 14% reduced size compared with marketed product.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.42 no.2 s.302
• /
• pp.19-26
• /
• 2005

This paper is about designing and implementation of Multi-Function UHF RFID Reader Platform that receives and processes RFID tag data from the tags, and transmits the data to PC server through Bluetooth, USB, RS-232 or Ethernet. This reader system is composed of RFID module, ARM processor, RS-232 interface, USB, Ethernet MAC interface, Bluetooth etc.. This paper also provides a brief overview and concept of RFID reader, and proposes the design and implementations of the RFID reader platform. The paper evaluates and analyzes two practical implementations, fixed type and portable type.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.19 no.4
• /
• pp.411-417
• /
• 2008

This paper presents the miniaturization of circularly polarized microstrip patch antenna for UHF-band RFID portable reader. The proposed antenna has a group of four I-slots on a conventional corner-truncated square microstrip patch and it is shown that the antenna size is reduced compared to the antenna without I-slots. A 76 mm by 76 mm small antenna with four I-slots is fabricated with 6.4 mm thick FR4 substrate and its 10 dB return loss bandwidth, the gain and the axial ratio are measured to be $938{\sim}975\;MHz$, $-0.88{\sim}-2\;dBi$, and $3.27{\sim}13.21\;dB$ within the 10 dB return loss bandwidth, respectively.

• The Journal of the Korea Contents Association
• /
• v.7 no.7
• /
• pp.31-38
• /
• 2007

We implement the RFID middleware system based on XML for large-scale data processing. The Implemented middleware system are consist of the reader interface for tag data collection, the event manager for a data filtering, and application interface for the RFID application. The implemented RFID middleware system is to support both a fixed type's reader and portable type's reader. we analyze the middleware function with four application accessing protocol, HTTP, XML, JMS, and SOAP, and demonstrate a filtering speed in terms of CPU utilization.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.1
• /
• pp.15-21
• /
• 2016

In this paper, we considered a design method of a compact quasi-Yagi antenna for portable UHF RFID readers. The antenna consists of a dipole driver and a reflector printed on a dielectric substrate, and it is fed by a microstrip line. In order to reduce the antenna size, the dipole and reflector are bent and the balun between the feeding microstrip line and coplanar strip (CPS) line is integrated within the CPS line. The effects of the geometrical parameters of the proposed antenna on the antenna performance are examined, and the parameters are adjusted to be suitable for the operation in UHF RFID band (902-928 MHz). The size of the fabricated antenna is $70mm{\times}75mm$, and the experiment results reveal a frequency band of 892-942 MHz for a voltage standing wave ratio < 2, a gain > 3.5 dBi, and a front-to-back ratio > 6.6 dB over the frequency band for UHF RFID.

• Journal of Digital Convergence
• /
• v.7 no.4
• /
• pp.149-158
• /
• 2009

Although current RFID technologies can provide wide advantages in food industry area, most food companies do not consider willingly adopting this technology yet. This paper will present how the effective implementation of RFID systems in food industry could be realized. To Measure the importance of RFID systems, this study utilized the BMT(Bench Mark Test) methodology using RFID systems that were composed of tag and reader. After conducting this study, it suggests the effective tag attachment methods on the objects. The results are shown that the excellent tag product is a RFCamp and a fixed reader of Thingmagic Mercury 4 is the best product. Also, a portable reader of Motorola MC9090-RFID is recommend to the highest product. Therefore, this test is useful for selecting the best RFID systems to the food industry area. In addition, this study displays the effective tag attachment method to each bottle that was used to the experiments in food industry. Therefore, this study is contributed to the not only importance in the government IT areas as a growth engine but also the importance for consumer as a right for the knowledge about the food quality.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.19 no.4
• /
• pp.404-410
• /
• 2008

In this paper, circular polarized microstrip antenna with a conducted hollow cylinder-typed via around the coaxial probe is proposed to enhance the bandwidth of an RFID portable reader microstrip antenna. An antenna of thickness of 6.4 mm and size of $84{\times}84\;mm$ is manufactured with FR4 substrate and its 10 dB return loss bandwidth is measured to be 92 MHz, which is about three times large than the same size's microstrip antenna without hollow cylindrical via. The measured antenna gain and the axial ratio at each are $0.01{\sim}1.825\;dB$ and $2.3{\sim}8.2\;dB$ within 10 dB return loss bandwidth, respectively.

• 한국정보통신설비학회:학술대회논문집
• /
• 2009.08a
• /
• pp.289-292
• /
• 2009

In this paper, an optimum design center frequency proposes portable RFID reader antenna that is 920MHz frequency using the Taguchi's Method. Proposed antenna is cut corner of opposite angle and it's structure that have slots in four sides microstrip patch of a perfect square shape. This slot structure can miniaturize microstrip patch antenna and confirmed through an experiment that size of antenna about 18% decreases than structure that slot does not exist. Because compact antenna that have structure of slot changes according to complex design variables, analysis and experimental design for minimization of experiment number of times are required for optimum antenna design. In this research, designed antenna that have optimum structure when introduce and designs table of orthogonal arrays of the Taguchi's Method been experimental design that can minimize analysis and experiment number of times, achieve responsiveness analysis of main elements and analyzes the effect and minimizes design repeat with analysis result. Presented experiment result about antenna special quality that permittivity is 4.4 and manufactures to board of Epoxy 3.2T.

• Journal of Broadcast Engineering
• /
• v.19 no.6
• /
• pp.934-941
• /
• 2014

In this paper, we present a low profile 2-layered meander built-in monopole antenna for portable RFID reader using FDTD(Finite Difference Time Domain) method. The input impedance, return loss, and VSWR in the frequency domain are calculated by Fourier transforming the time domain results. The double meander 2-layer structure is used to enhance the impedance matching and increase the antenna gain. The measured bandwidth of the antenna is 0.895 GHz ~ 0.930 GHz for a S11 of less than -10dB. The measured peak gain of proposed low profile RFID built-in antenna is 2.3 dBi. And the proposed built-in antenna for portable RFID reader can offers relatively wide-bandwidth and high-gain characteristics, in respectively. Experimental data for the return loss and the gain of the antenna are also presented, and they are relatively in good agreement with the FDTD results. This antenna can be also applied to mobile communication field, energy fields, RFID, and home-network operations, broadcasting, and other low profile mobile systems.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.10
• /
• pp.1491-1497
• /
• 2013

Radio frequency identification (RFID) is an important and essential components of ubiquitous computing, with the development of wireless communication technologies and mobile computing environment. Recently, RFID becomes the mainstream application that helps fast handling and uniquely identifying the physical objects. It utilizes the electromagnetic energy for data transmission from a tag to a reader in the presence of arbitrary interference and noise. In order to employ the portable mobile RFID reader, a tag-collision problem between two or more adjacent tags should be considered. In this paper, we present the operation of RFID system in which numerous tags are present in the interrogation zone of a single reader at the same time. Since there may exist a number of tagged objects in the narrow area, multiple RFID tags may interfere each other, caused to degrade the data reliability and efficiency of the RFID system. In order to suppress interference signals from multiple neighboring tags, we present an application of Gold code for RFID communication system, which uses spread spectrum technique. In this RFID system, data bits are spreaded in each tags with the unique Gold code and the spreaded data bits are despreaded in the reader with the same Gold code. The performance analysis of the considered RFID anti-collision system is illustrated via computer simulation examples.