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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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The Journal of Korean Institute of Electromagnetic Engineering and Science
Journal Basic Information
Journal DOI :
The Korean Institute of Electromagnetic Engineering and Science
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Volume & Issues
Volume 17, Issue 12 - Dec 2006
Volume 17, Issue 11 - Nov 2006
Volume 17, Issue 10 - Oct 2006
Volume 17, Issue 9 - Sep 2006
Volume 17, Issue 8 - Aug 2006
Volume 17, Issue 7 - Jul 2006
Volume 17, Issue 6 - Jun 2006
Volume 17, Issue 5 - May 2006
Volume 17, Issue 4 - Apr 2006
Volume 17, Issue 3 - Mar 2006
Volume 17, Issue 2 - Feb 2006
Volume 17, Issue 1 - Jan 2006
Selecting the target year
A Study on the Development and Optimization Design of Isolator by Using the 3D Simulator
Jung Seung-Woo ; Choi U-Sung ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 229~238
In this paper, developed study about isolator that after design and optimizes center strip to use 3-D simulator. We use the factor about the change and propose simple mode of the simulation. Design strip line that center frequency is 1.85 GHz by software that use 3-D finite element method(FEM) and confirmed variable. Developed isolator were shown that more than isolation 25 dB, reflection loss has the more than 25 dB and insertion loss does not 0.2 dB. We could confirm that compare with simulation and manufacture sample propertied agrees more than 90 %.
Design and Fabrication of the Cryogenically Cooled LNA Module for Radio Telescope Receiver Front-End
Oh Hyun-Seok ; Lee Kyung-Im ; Yang Seong-Sik ; Yeom Kyung-Whan ; Je Do-Heung ; Han Seog-Tae ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 239~248
In this paper, the cryogenically cooled low noise amplifier module for radio telescope receiver front-end using pHE-MT MMIC is designed and fabricated. In the selection of MMIC, the MMIC fabricated with the pHEMTS providing successful cryogenic operation are chosen. They are mounted in the housing using the thin film substrate. In the design of the housing, the absorber and the elimination of the gap between the carrier and the housing as well removed the unnecessary oscillations by its structure. The mismatch is improved by ribbon-tuning to provide the best performance at room temperature. The fabricated module shows the gain of
and the noise figure of
at room temperature over
. In the cryogenic temperature of
cooled by He gas, the measured gain was above 35 dB and flatness
and the noise temperatures of
On the Design of Multi-layered Polygonal Helix Antennas
Choo Jae-Yul ; Choo Ho-Sung ; Park Ik-Mo ; Oh Yi-Sok ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 249~258
In this letter, we propose a novel printed helix antenna for RFID reader in UHF band. The printed strip line of the antenna is first wound up outside a polygonal shaped layer and then the winding continues on an inner layer to control the overall gain and the radiation pattern. In addition, the winding pitch angles on each layer have either negative or positive values resulting in the broad CP bandwidth. The detail structure of the antenna was optimized using Pareto genetic algorithm(GA), so as to obtain excellent performances for RFID reader antennas. The optimized two-layered polygonal helix was fabricated on the cardboard of a flexible substrate and the performances were measured and compared with the simulations. The fabricated antenna was made up of copper tape which can adhere to a flexible cardboard and had 21.4 % matching bandwidth, 31.9 % CP bandwidth, readable range of
with kr=3.2. Also based on the current distribution of the strip line of the antenna and sensitivity of the antenna bents points, we confirmed that the antenna has the quarter-wave transformer near the feed for the broad matching bandwidth and radiates the traveling wave for the broad CP bandwidth using the bent strip line.
Propagation Characteristics from Ingested Sources in Human Body
Kim Bo-Mi ; Kim Young-Sik ; Kim Se-Yun ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 259~266
This paper presents the propagation characteristics from ingested sources in human body using the human model simulator. The simulator applies the FDTD method to the human data consisting of the human CAD and tissue data. After the accuracy of the simulator is verified, the received fields at one horizontal layer including the small intestine among the digestive organs are calculated in case that the electric field source is implanted in the center of the small intestine. The human propagation characteristics are illustrated by calculating the path loss per unit length according to various received positions from the simulated results.
Ergodic Capacity Analysis of OFDM Transmission Channel Applied to the MIMO Antennas Considering Spatial Propagation Property
Kim Chang-Joong ; Lee Ho-Kyoung ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 267~271
In this paper, we use the OFDM transmission channel model applied to the MIMO antennas considering spatial propagation property to evaluate and investigate the ergodic capacity of the channel. Specially, we have applied our results to 3GPP TR 25.99 V1.1.0 case 1 LOS off channel description and calculated ergodic capacity with parameters, cluster angle spread and angle of arrival(AOA). Our results show that as the cluster angle spread increase the channel capacity increase until 35 degree, but for more than 35 degree channel capacity does not improved.
Performance Evaluation of Frame Synchronization Using Pilot Patterns in W-CDMA System
Song Young-Joon ; Kim Han-Mook ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 272~279
In this paper, we evaluate the performance of frame synchronization words of pilot bit patterns which are used for the channel estimation and frame synchronization confirmation in W-CDMA(Wide band Code Division Multiple Access) system. W-CDMA system also uses compressed mode to make measurements from another frequency without a full dual receiver terminal. It is confirmed by using computer simulation that the proposed frame synchronization words also maintain the frame synchronization property in the compressed mode by using the complementary mapping relationship of preferred pair ROC(Receiver Operating Characteristic) curves with probability of detection and false alarm are used to analized the performance of the proposed frame synchronization words by using the various detection metrics such as LLRT(Log Likelyhood Ratio Test), GLRT(Generalied Likelyhood Ratio Test), soft and hard correlation tests in AWGN and Rayleigh fading channels. It is expected that the research results fer the performance of pilot bit patterns of this paper can be useful reference for the design and implementation of frame synchronization in 3rd generation W-CDMA system.
Feeding Point Determination for Optimum Performance of PIFA Internal Antenna for the Mobile Phone Handset
Son Tae-Ho ; Lee Jae-Ho ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 280~286
Determination method of optimum feeding point for the PIFA type internal antenna for the mobile phone handset was studied. Fundamental theory is that radiated gain is basically depended upon the electric field strength between PIFA conductor and ground plane. Feeding point, slit configuration, material and structure of carrier are main factors fur the PIFA performances. It is shown that maximum electric field strengths of other feeding points decrease in -2dB to -10 dB than optimum point. Ansoft HFSS EM simulator was applied to determine the best feeding point for 2 models of Samsung Electronics mobile phone handset.
Characterization and Analysis of UWB Antennas in Time Domain
Song Jong-Hwa ; Park Young-Jin ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 287~294
In the paper, characterization and analysis of UWB(Ultra Wide Band) antennas in time domain are described. The impulse propagation channel including UWB antennas is proposed for the analysis in time domain. Using the proposed propagation channel, the technique of obtaining impulse response of UWB antenna is proposed. Also, ringing, peak value of the impulse response, and the width of the impulse response are introduced as parameters for characterizing a UWB antenna in time domain. A modified UWB conical monopole antenna, a UWB TEM horn antenna, and a UWB stepped fat monopole antenna were fabricated. From the measurement of reflection coefficients, three antennas had bandwidth more than 3 GHz. The impulse responses of the antennas were measured in an anechoic chamber. The results showed that the TEM horn with highest gain has the highest peak amplitude and the stepped fat monopole antenna with narrowest bandwidth for reflection coeffcient had the widest width of the impulse response. Also, ringing in the stepped fat monopole antennas and the UWB conical monopole antenna were observed.
A Study of Fiber Reinforce Ceramic Composite for Protecting Antenna Cover of Ultrafast Aircraft
Jung Yeong-Chul ; Lee Kyung-Won ; Yook Jong-Gwan ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 295~306
In this paper, we proposed and implemented a novel antenna cover mounted over a microstrip path antenna for ultrafast aircraft. A protective antenna cover prevents alteration in the electrical characteristics of the antenna due to environmental conditions. The permittivity of the cover materials should be practically invariable at all operating frequencies. We evaluated the characteristics of the antenna with both simulation and experiment. The experimental results show that the proposed antenna cover can be useful for ultrafast aircraft.
An Advanced MCL Method for a Sharing Analysis of Mobile Communication Systems beyond 3G
Chung Woo-Ghee ; Yoon Hyun-Goo ; Jo Han-Shin ; Lim Jae-Woo ; Yook Jong-Gwan ; Park Han-Kyu ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 3, 2006, Pages 307~316
In this paper the analytical method, namely advanced minimum coupling loss(A-MCL), was proposed in order to analyze the coexistence of OFDM-based systems beyond 3G(B3G) with point-to point(PP) fixed service(FS) microwave systems. Our proposed method is based on a power spectral density(PSD) analysis. So it can be easily applicable to analyze the coexistence of OFDM-based systems B3G using flexible spectrum usage(FSU) with other systems, where the conventional MCL method cannot allocate transmit power partially to some subcarriers which overlap the band of a victim system. By applying the conventional MCL method and the A-MCL method, interfering power levels at the receiver of a interfered system are respectively calculated. A-MCL can calculate interference power more accurately than MCL by the maximum value of 4.5 dB. Therefore it can be concluded that our prosed method, namely A-MCL, is applicable to a sharing analysis of OFDM-based systems B3G.