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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
Research on PAE of Doherty Amplifier Using Dual Bias Control and PBG Structure
Kim Hyoung-Jun ; Seo Chul-Hun ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 707~712
In this paper, dual bias control circuit and PBG(Photonic BandGap) structure have been employed to improve PAE(Power Added Effciency) of the Doherty amplifier on Input power level. The gate and drain bias voltage has been controlled with the envelope of the input RF signal and PBG structure has been employed on the output port of Doherty amplifier. The proposed Doherty amplifier using dual bias controlled circuit and PBG has been improved the average PAE by 8%,
by -5 dBc. And proposed Doherty amplifier has a high efficiency more than 30% on overall input power level, respectively.
Fabrication of Folded Monopole Antenna for Quintuple Band Mobile Phone Handset
Jang In-Seok ; Son Tae-Ho ; Lee Jae-Ho ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 713~718
We designed and fabricated, in this paper, a quintuple band folded monopole antenna for the mobile phone handset that can be provided multiple mobile services. Antenna design was based on the compensation of series antenna capacitance with the expansion of physical antenna length by the proper folding structure. It's shown that this antenna satisfies quintuple service band as CDMA/GSM/DCS/USPCS/WCDMA, and is more cost competitive than conventional metal plate pressing method by applying on flexible PCB technology. Measured maximum gain on quintuple band were
, and radiation patterns were also shown nearly omnidirectional on all bands.
Design of Double-Conversion Down Mixer Using Single Half-LO Frequency at 2.3 GHz
Kim Min-Seok ; Moon Ju-Young ; Yun Sang-Won ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 719~724
In this paper, we designed the double conversion down mixer by using Half-LO frequency in 2.3 GHz band. The IF frequency is obtained by supplying two LO frequencies to HEMT in both gate type and resistive type. The proposed mixer uses Half-LO frequency the same way as conventional sub-harmonic mixers. However the proposed one uses fundamental component of Half-LO frequency in first stage instead of using second harmonic components of Half-LO frequency, and the IF frequency is obtained by resistive type mixer in second stage, thereby the proposed mixer can improve linearity in comparison with conventional active mixer. We can verify that the proposed mixer has an conversion loss of 5dBm and IIP3 of 16.25dBm by using 10 dBm Power
A Novel Design of Frequency Multiplier Using Feedforward Technique and Defected Ground Structure
Park Sang-Keun ; Lim Jong-Sik ; Jeong Yong-Chae ; Kim Chul-Dong ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 725~731
A novel design of frequency multiplier using a feedforward technique and a defected ground structure(DGS) is proposed. The feedforward loop in the proposed frequency multiplier suppresses the fundamental component
, the dumb-bell or spiral shaped DGS diminish unwanted harmonics such as second, third and fourth. Due to the combination of the feedforward structure and the DGS, only the multiplied frequency component
appears at the output port and the other unwanted components are suppressed excellently. The frequency multiplier is designed at 1 GHz
, by the proposed technique and measured. The measured output power of
is -2.59 dBm, -5.36dBm and -4.57dBm, respectively, when the input power is 0dBm.
10 GHz TSPC(True Single Phase Clocking) Divider Design
Kim Ji-Hoon ; Choi Woo-Yeol ; Kwon Young-Woo ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 732~738
Divide-by-2 and divide-by-4 circuits which can operate up to 10 GHz are designed. A design method used in these circuits is the TSPC(True Single Phase Clocking) topology. The structure of the TSPC dividers is very simple because they need only a single clock and purely consist of smalt sized cmos devices. Through measurements, we find the fact that in proportion to the bias voltage, the free running frequency increases and the operation region also moves toward a higher frequency region. For operating conditions of bias voltage
, input power 16dBm and dcoffset
, 5 GHz and 2.5 GHz output signals divided by 2 and 4 are measured. The layout size of the divide-by-2 circuit is about
except pad interconnection part).
Microwave Group Delay Time Adjuster Using Resonance Circuit
Seo Su-Jin ; Park Sang-Keun ; Choi Heung-Jae ; Jeong Yong-Chae ; Yun Jae-Hun ; Kim Chul-Dong ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 739~745
This paper presents a method to control group delay tine using a resonance circuit. The group delay time adjuster(GDTA) that can control signal group delay time comprises a variable capacitance and a variable equivalent inductor. These are coupled in parallel at a node and also controlled by two bias voltages separately, A variable equivalent inductor is realized a transmission line terminated a variable capacitor. Group delay time can be controlled by change of capacitance and inductance, but the resonating frequency is fixed. When the proposed GDTA is fabricated on RFID Korean frequency band
, a group delay variation is obtained about 3 ns.
Partial H-plane Filter with Periodic Structure
Kim Dong-Jin ; Chung Woo-Sung ; Lee Jeong-Hae ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 746~752
In this paper, a compact partial H-plane filter with periodic structure is proposed. Guided wavelength of periodic structure' is reduced by slow wave effect. Cross-section and length of partial H-plane filter with periodic structure are considerably reduced by 75% and 30%, respectively, as compared with conventional E-plane filter. In addition, spurious responses of the bandpass filter are improved. To design bandpass filter with periodic structure, we have analyzed a periodic structure of partial H-plane waveguide and derived equations of the periodic filter. Measured results are in good agreement with simulated results.
On the Design of High Order Transformer Circuit Using the Genetic Algorithm and Its Application to the Wheeler Cap Measurement
Cho Chi-Hyun ; Choo Ho-Sung ; Park Ik-Mo ; Kang Jin-Seob ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 753~759
Generally, the Wheeler cap method is used to measure the efficiency of small antennas. This method often gives an unreliable efficiency when the antenna has a complicated operating principle. However, if the high-order circuit model which more closely represents the input impedance of the antenna is used in Wheeler cap method, then more accurate efficiency can be achieved. In this paper, we propose a novel method that can build the high-order circuit model using transformer circuits with the genetic algorithm(GA). To efficiently reduce the searching space in the GA and improve the convergence of the GA process, we suggest a novel scheme that finds appropriate initial values. Finally we verify the proposed method by measuring the efficiency of some passive RFID tag antennas.
Design and Implementation of Wideband Patch Antenna with Folded and Shorted Structure for 5 GHz WLAN
Kim Yong-Hee ; Han Jun-Hee ; Lee Won-Kew ; Yang Woon-Geun ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 760~766
In this paper, we present a wideband patch antenna with folded and shorted structure for 5 GHz WLAN(Wireless Local Area Network). The proposed antenna used folded and shorted structure in the rectangular patch for miniaturization and wide frequency bandwidth. The antenna was designed by using 3D simulation program, HFSS(High Frequency Structure Simulator) software of the Ansoft company and the implemented antenna was measured by using HP 8720c network analyzer and far field measurement chamber. Simulation result on the return loss shows fairly good characteristic of at least 13.41dB in whole frequency range of interests, and the 10dB bandwidth is 1,523MHz which shows wide bandwidth characteristic. And the simulated maximum gain of the proposed antenna is 6.57 dBi at 5.825GHz. Measured result for the 10dB bandwidth of the implemented folded and shorted structure antenna is 1,377 MHz. Measured maximum gain of the implemented antenna is 6.87dBi at 5.775GHz. Measured results for the implemented antenna showed applicable performances for the 5 GHz WLAN.
Dual-band Monopulse Receiver for Tracking Radar
Yang Seong-Uk ; Park Dong-Min ; Na Young-Jin ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 767~772
The receiver of this paper is Dual-band monopulse type for prototype of tracking radar. Localization of radar technology is an issue of SamsungThales and go into development. Dual-band radar in comparison with Single-band radar requires higher cost and power consumption but there are many advantages of dealing with jamming, detection range, image signal rejection, cloud-rain influence, clutter, resolution. The receiver is comprised of X-band RF head module, Ka-band RF head module and common IF module. Each signal of X-band and Ka-band is selected by the switch in If module. Phase shifter in IF module of local stage controls the phase of sum, azimuth, elevation channel. In the test result, gain is
, isolation of transmitter/receiver is 39 dBc, dynamic range is 110 dB and noise figure of each channel is 4.5dB and 6.9dB
X-band Pulsed Doppler Radar Development for Helicopter
Kwag Young-Kil ; Choi Min-Su ; Bae Jae-Hoon ; Jeon In-Pyung ; Hwang Kwang-Yun ; Yang Joo-Yoel ; Kim Do-Heon ; Kang Jung-Wan ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 773~787
An airborne radar is an essential aviation electronic system for the aircraft to perform various civil and/or military missions in all weather environments. This paper presents the design, development, and test results of the multi-mode X-band pulsed Doppler radar system test model for helicopter-borne flight test. This radar system consists of 4 LRUs(Line-Replacement Unit), which include antenna unit, transmitter and receiver unit, radar signal & data processing unit and display Unit. The developed core technologies include the planar array antenna, TWTA transmitter, coherent I/Q detector, digital pulse compression, MTI, DSP based Doppler FFT filter, adaptive CFAR, moving clutter compensation, platform motion stabilizer, and tracking capability. The design performance of the developed radar system is verified through various ground fixed and moving vehicle test as well as helicopter-borne field tests including MTD(Moving Target Detector) capability for the Doppler compensation due to the moving platform motion.
Exact Evaluation of a Sommerfeld Integral for the Impedance Half-Plane Problem
Koh Il-Suek ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 17, issue 8, 2006, Pages 788~794
In this paper, a Sommerfeld integral for an impedance half-plane is considered, which is one of classical problems in electromagnetic theory. First, the integral is evaluated into two series representations which are expressed in terms of exponential integral and Lommel function, respectively. Then based on the Lommel function expansion, an exact, closed-form expression of the integral is formulated, written in terms of incomplete Weber integrals. Additionally, based on the exponential integral expansion, an approximate expression of the integral is obtained. Validity of all formulations derived in this paper is demonstrated through comparisons with a numerical integration of the integral for various situations.