Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Journal of Korean Institute of Electromagnetic Engineering and Science
Journal Basic Information
Journal DOI :
The Korean Institute of Electromagnetic Engineering and Science
Editor in Chief :
Volume & Issues
Volume 12, Issue 7 - Dec 2001
Volume 12, Issue 6 - Oct 2001
Volume 12, Issue 5 - Aug 2001
Volume 12, Issue 4 - Jun 2001
Volume 12, Issue 3 - Apr 2001
Volume 12, Issue 2 - Feb 2001
Volume 12, Issue 1 - Jan 2001
Selecting the target year
Improvement of the Microstrip Patch Bandpass Filter using Interdigital Couping Structure and Embeded Slot
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 487~493
In this paper, A new microstrip bandpass filter is proposed. The novelty of the proposed structures is to use a interdigital capacitor and embeded slot that are fanned on a patch resonator such that its insertion loss and size can be significantly reduced simultaneously. As a result, it is found that the resonant frequency of patch filter designed at 5 GHz is decreased to 1.8946 GHz and the insertion loss is reduced from -2.168 dB to -0.379 dB. This proposed filter has small size and low insertion loss in comparison with the conventional parallel edge coupled bandpass filter.
Design and Implementation of Combined RF Receiver Front End for GPS/GLONASS
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 494~502
GPS(Global Positioning System) and GLONASS(GLObal Navigation Satellite System) are basic technologies providing the information of the position and the time, and they have various applications such as navigation, survey, control, and so on. However, each GPS and GLONASS has limited number of visible satellites, and, from the view of strategy, it is undesirable to be heavily dependent on only one system. Thus, GPS/GLONASS combined receiver became required to obtain more precise navigation and system stability. In this paper, the RF front end of GPS/GLONASS combined receiver was fabricated on 130
PCB(Printed Circuit Board), and its system application was shown finally one chip possibility of GLONASS receiver is studied.
Adaptive Predistorter for Power Amplifier based on Real -Time Estimation of Envelope Transfer Characteristics
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 503~512
A new adaptation algorithm for the digital predistorter is presented. The proposed technique employs the real-time transmitted signals through HPA for the table update. Hence the proposed algorithm does not depend on modulation format and the signal transmission of HPA is not affected during the adaptation process. The experimental results are presented to verify the proposed method and we obtained about 8.4 dB of ACPR improvement.
A Study on the Design of the Directional Coupler using Three Layer Microstrip Substrate
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 513~520
In this paper, the directional coupler using three layer microstrip substrate is proposed and the design method is notified. Modified re-entrant mode coupler is the proposed structure that one layer is added on upper plane of coupled transmission lines and the floating conductor is placed on added layer's upper planes. This structure has high coupling for the increase of odd mode capacitance and also has good performance in VSWR, isolation, phase difference because the difference of effective permittivity is small in each mode. We have designed the coupler from the calculation of impedance, effective permittivity, coupling coefficient using even, odd mode analysis method. From the simulation and measurement, proposed coupler has about 2 dB more tighter coupling than conventional coupler and also has good performance in VSWR, isolation, phase difference.
The Detection Method of a Target Position above a Ground Medium using the Buried Antenna
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 521~531
This paper presents the extraction scheme of the scattered waves by a target above the ground using the buried antenna in a lossy and dispersive medium. The half wave dipole antennas are used to transmit and to receive a signal. The transmission line model as a feeding model is considered to take into account the effect of transmission line in a real system. The ground is modeled by the 2nd order Debye approximation with the dispersion and loss. PLRC algorithm and DPML as absorbing boundary condition are utilized to apply the 2nd order Debye approximation to FDTD. To extract the scattered wave, in addition, we employed the delay time extraction algorithm. The simulations are conducted to observe the variation of magnitude in scattered wave and detection of target position according to the change of moisture content of the lossy medium.
Gain Analysis of the Radome Circular Microstrip Antenna using the Attachment Mode
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 532~541
In the case of the microstrip antenna with the coaxial probe-feeding, there is rapidly-varying patch current near the point where the probe feed is connected to the patch. We represent this current distribution using the attachment mode that insures continuity of currents from the feed to the patch. In this paper, we can accurately analyze the effect of a cover layer or radome for an antenna with the attachment which model rigorous probe feed.
Design of a Channel Combiner for Digital Terrestrial Television Transmission
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 542~550
In this paper, a channel combiner is designed to combine two adjacent digital TV channels without interference to transmit these channels with one broadband antenna. A constant impedance type combiner, consisting of two identical bandpass filters and two identical 3 dB power combiners, is chosen as a channel combiner. The bandpass filter used in the channel combiner also suppresses out-of-band signal caused by digital transmitter's non-linearity. H-plane type bandpass filters and branch-line fewer combiners are adopted in the design. The simulated results of the designed bandpass filter and power combiner show excellent agreement with the theoretical results. Finally, a channel combiner is designed by combining filters with rover combiners and the characteristics are simulated. It is shown that the designed channel combiner shows excellent performance.
Large Signal Unified Model for GaAs pHEMT using Modified Curtice Model
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 551~561
In this paper, the large signal unified model is established for H4O GaAs pHEMT of GEC-Marconi using modified Curtice model. This unified model includes DC characteristic, small signal, and noise characteristic as various bias. Particularly, the model can simply and physically explain trans-conductance
of pHEMT using modified Curtice model, and can tell the difference
at DC and these at AC through inclusion of internal RF-choke. The results of the established model built up using SDD in HP-Eessof show good agreement to the S/W measured data in DC, small signal, and noise characteristic. This model can also be applied to various computer aided analysis, such as linear simulation, 1-tone harmonic balance simulation, and multi-tone harmonic balance simulation, so the LNA(Low Noise Amplifier), oscillator, and mixer design has been shown using this model library.
Optimum Design of T-shaped Microstrip-line-fed Slot Antennas
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 562~569
This paper presents the optimum design method for T-shaped microstrip-line-fed slot antennas on various substrates. Since the impedance bandwidth of the antenna depends highly on the vertical offset position and the length of horizontal strip conductor, we derived the formulas regarding these design parameters to get the maximum bandwidth. The formulas can compute the offset position and the length of horizontal strip conductor for any given substrate parameters. We compared the results obtained by using these design formulas and the one obtained by the simulation for each slot width, and it showed very good agreement.
Minimum Duration Outage of a DS-CDMA Cellular System Due to Cell Traffic Intensity
Kim, Nam-Soo ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 570~575
The minimum duration outage probability of a cellular system is defined the probability that the received signal level is hold under minimum required threshold duration. This definition is more realistic compared to the outage probability which is the received signal strength level is below predefined threshold level. Especially, in a DS-CDMA cellular system the received signal-to-interference ratio is a function of cell traffic, while the former researches are only considered the minimum duration outage probability independent of the cell traffic. We noticed that the minimum outage probability is rapidly increases as cell traffic increase.
Compensation of Chromatic Dispersion and Self Phase Modulation in Long-haul Optical Transmission System using Mid-span Optical Phase Conjugator
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 576~585
In this paper, we investigated the method of compensation for optical pulse shape distortion due to both chromatic dispersion and SPM(self phase modulation) in a single mode fiber We selected MSSI(mid-span spectral inversion) as compensation method using OPC(optical phase conjugator). We used EOP(eye-opening penalty) parameter in order to evaluate the efficiency of waveform distortion compensation. In this paper, we induced optimum pump power level in optical phase conjugator through analytic method of computer simulation. And we investigated input signal power range being able to maintain stable reception performance under the condition of optimum pump power. We verified the possibility of high performance optical transmission system realization through the inducement and application of optimum pump power, input signal power and in-line amplifier spacing, because power control is important in the compensation for optical pulse distortion.
Comparison between Path-loss Prediction Models fot Wireless Telecommunication System Design
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 586~593
LPI Performance Analysis of GMSK Modulation Scheme
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 594~599
The symbol rate which is the main feature of NRZ information signal is detected by DAM (Delay-And-Multiplier) receiver. It is important for secure communication to reduce the normalized output SNR which is calculated at the DAM output as a measure of detectability. In this paper, we use the signal which is modulated by the class of MSK modulation schemes as the input signal of the DAM receiver for analyzing LPI performance and the GMSK(BT=0.3) used in GSM system is highlighted. Consequently, GMSK which has better bandwidth efficiency than other modulation schemes(BPSK, QPSK, OQPSK, and MSK) has better LPI performance compared with other ones. To compare the performances of each modulation scheme fairly, the transmitted powers of each system are set to be same within useful bandwidth.
Effects of Group Delay and Non-linear Characteristics in Ka-Band High Data Rate Satellite Communication System
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 600~610
The effects of group delay and non-linear characteristics on high data rate(HDR) satellite channel are presented in this paper Based on the modeling of group delay and non-linear characteristics the system performances which provide various data rate services were analyzed in Ka-band satellite channel. As the transmission data rate is increased, the degradation due to these channel characteristics is severely increased. The linear component of group delay and the AM-AM component of non-linear characteristics severely affect the system performance. To efficiently provide the various service via the same transmission system it is necessary to equalize the primary impairment factors. The optimum operating points of HDR satellite transmission system are implemented by considering the analyzed results on channel characteristics.
Design of Microstrip Line Bandpass Filter using Photonic Bandgap Structures
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 611~621
This paper presents a design methodology of bandpass filter by using defect modes in photonic bandgap (PBG) structures. PBG structures are realized with alternating section of microstrip line arranged in a periodical manner. A passband is created within the stopband of PBG structures with defect modes, which can be generated by changing the period of certain part of PBG structure. We also extract a simple equivalent circuit of a bandstop filter by using several LC sections.
Nonlinear Design of Engineering Model Oscillator with a Very Low Phase Noise fot Satellite Transponder
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 622~629
An engineering model VCO with a good phase noise for Ku-band satellite transponder is designed using a nonlinear design methodology. It generates frequencies from 1,745 and 1,755 MHz with control voltages from 0 to 5 V DC. This unit requires 7 mA of current from 5 V DC supply voltage. Phase noise characteristics of the manufactured VCO exhibit -114 dBc/Hz @10 kHz offset and -131 dBc/Hz @100 kHz of offset and its output power is 5 dBm.
Performance Analysis of a Multi-Carrier DS-CDMA/BPSK Signal with Hybrid SC/MRC-
Diversity Reception in Multipate Fading Channe
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 630~643
In this paper, the performance of a Multi-Carrier DS-CDMA system with Hybrid
diversity in the multipath Rayleigh fading environment is analyzed and compared with that of a Wideband DS-CDMA system. Each carriers of the number of the input diversity branches in the Multi-Carrier DS-CDMA system is L and among L, the branches of
are chosen to be maximum-ratio-combined. And the diversity outputs are coherent-detected and despread by the correlator of each carrier. As the result, we have known that the structure of the Wideband DS-CDMA system with Hybrid
diversity reception becomes simple due to no synchronization of bit or phase and in terms of the error performance, the performance of Hybrid
diversity is better than that of selection diversity, but worse than that of MRC diversity. Moreover, the performance of a Multi-Carrier DS-CDMA system is better than that of a Wideband DS-CDMA system in multipath Rayleigh fading channel since Hybrid
diversity can obtain gain from each diversity branch. In case four carriers are used and required BER is
in wireless data communication, Hybrid SC/MRC-2/4 diversity can increase more 17 users than Hybrid SC/MRC-2/3 diversity because the better input branches can be selected through increase of input branches.
A Study on Remotely Located Synchronization System using GPS Common-View Method
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 644~650
A remotely located synchronization system which is locked to the remote master clock has been implemented by using GPS Common-View technique. The measurement results showed that the accuracy of the remote synchronization system could be kept within a few parts in
and MTIE(Maximum Time Interval Error) met the ITU-T Recommendation(G.811). A prototype system having fully automatic operational functions has been realized up to now and is expected to be used in the network synchronization in the near future.
Design of A Microwave Planar Broadband Power Divider
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 12, issue 4, 2001, Pages 651~658
A novel multi-section power divider configuration is proposed to obtain wide-band frequency performance up to microwave frequency region. Design procedures for the proposed microwave broadband power divider are composed of a planar multi-section three-ports hybrid and a waveguide transformer design procedures. The multi-section power divider is based on design theory of the optimum quarter-wave transformer. Furthermore, in order to obtain the broadband isolation performance between the two adjacent output ports, the odd mode equivalent circuit should be matched by using the lossy element such as resistor. The derived design formula for calculating these odd mode matching elements is based on the singly terminated filter design theory. The waveguide transformer section is designed to suppress the propagation of the higher order modes such as waveguide modes due to employing the metallic electric wall. Thus, each section of the designed waveguide transformer should be operated with evanescent mode over the whole design frequency band of the proposed microwave broadband power divider. This paper presents several simulations and experimental results of multi-section power divider to show validity of the proposed microwave broadband power divider configuration. Simulation and experiment show excellent performance of multi section power divider.