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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 13, Issue 10 - Dec 2002
Volume 13, Issue 9 - Oct 2002
Volume 13, Issue 8 - Sep 2002
Volume 13, Issue 7 - Aug 2002
Volume 13, Issue 6 - Jul 2002
Volume 13, Issue 5 - Jun 2002
Volume 13, Issue 4 - Apr 2002
Volume 13, Issue 3 - Mar 2002
Volume 13, Issue 2 - Feb 2002
Volume 13, Issue 1 - Jan 2002
Selecting the target year
Analysis of Mutual Coupling between Antennas on Small UAV
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 407~415
In this paper, mutual coupling effect between antennas mounted on UAV(Unmanned Air Vehicle), operating In different frequency bands, is calculated for supposing efficient arrangement. For the calculation, FDTD method is used, simulation parameters are confined to distance between antennas, height of antennas, types of ground, etc. The simulation data are compared with those of other numerical method to confirm accuracy of the results. It is appeared that the critical factor of mutual coupling is height of an antenna relative to that of the other antenna.
A Study of Data Transmission Rate Measurement in 5 GHz Band Wireless LAN under the Influence of the Indoor Interference
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 416~425
In this Paper, It is analysed 5 GHz frequency characteristics that carry out interference experimental under the indoor environments for understanding propagation interference between existing 5 GHz band wireless communication system and 5 GHz band wireless LAN system. The interference signal which was generated by signal generator injected to 5 GHz Wireless LAN communication system measured interference characteristics and This radio propagation main interference factors were classified received power level separation by interference source frequency and interference source frequency pulse period & width separation. It is measured transmission rate according to variable data and packet size for conforming the quality of 5 GHz band wireless LAN system. We measured the packet data loss rate and power level of received signal and analyzed its frequency characteristics effected by interference signal.
The Indoor Propagation Modeling for Indoor Wireless LAN Service
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 426~435
In this paper we present an indoor propagation model for indoor wireless LAN service in the ISM band. We primarily use a 3D ray tracing as well as a patch scattering model in order to take into account the indoor fixtures. Therefore input parameters such as indoor environment parameters and antenna's types, polarizations are considered. As the results, we present fading characteristics and rms delay spread from time delay spread. In order to investigate the accuracy of the presented model, comparisons of predictions with measurement and simulations are performed in indoor wireless LAN service environments. The results show that measurements and simulations are very similar. Therefore in this paper, the effect of presented indoor propagation model is confirmed.
A Method to Reduce the Size of Amplifiers using Defected Ground Structure
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 436~444
This paper presents a new method, which uses defected ground structure (DGS) on the ground planes of planar transmission lines such as microstrip and coplanar waveguide (CPW), to reduce the size of amplifiers. The main idea can be summarized as follow; DGS on the ground plane of microstrip or CPW line shows an increased slow-wave effect due to the additional equivalent L-C components. So the electrical length of the transmission line with DGS is longer than that of the standard transmission line for the same physical length. Then, the length of the transmission line with DGS can be shortened in order to maintain the original electrical length to be the same. This leads the matching of the original amplifier to be kept. In order to show the proposed method is valid, two kinds of amplifiers, the original amplifier and reduced amplifier, are fabricated, measured, and compared using both microstrip and CPW. The measured performances of the reduced amplifiers with DGS are quite similar to the ones of the original amplifiers for both microstrip and CPW amplifiers, even though the size of matching networks of the amplifiers with DGS are much smaller than those of the original amplifiers.
Improved Coplanar Waveguide-to-Microstrip Right-Angled Transition using an Offset Microstrip Section
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 445~450
We analyzed and measured a CPW(coplanar waveguide)-to-microstrip right-angled transition. Asymmetric CPW-to-microstrip transitions show significant resonances by the slot mode generation at the discontinuities. The air-bridge just shifting the resonance frequency can not fundamentally suppress the occurrence of the slot mode. So, we proposed the structure using offset microstrip section to eliminate the resonance. The proposed structure may be useful for the application of multi-layed structure.
3:1 Bandwidth Switch Module by Using GaAs PH Diode
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 451~458
Absorptive type SP3T(Single Pole Three Throw) and SP8T switch modules over the 6-18 GHz are designed and fabricated. The epitaxial structure of GaAs PIN diode for switch modules are designed for low loss and high power capability. The maximum input power of SP3T and SP8T switch modules are 2 W and 1 W, respectively. The switching time with driver circuit is less than 130 nsec. The maximum insertion loss of SP3T switch module and SP8T module shows 2.8 dB and 4.2 dB, respectively. The isolation between input port and output port is more than 55 dB. Two switch modules for electronic warfare system have passed the environment tests of the related test items.
Design and Fabrication of a Planar Inverted-F Antenna for the Wireless LAN using the 5 GHz Band
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 459~467
A compact, lightweight and low-cost Planar Inverted-F Antenna(PIFA) for wireless LAN communication in the 5 GHz band is designed. The antenna is designed using the IE3D, the simulation tool of the Zeland Inc.. The characteristics of the implemented antenna are measured and analyzed. The antenna is resonated at the 5.25 GHz and its bandwidth is about 580 MHz under the condition of VSWR
Two-Arm Microstrip Spiral Antenna with a Circular Slot on the Ground Plane
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 468~474
In this paper a novel two-arm microstrip spiral antenna with a circular slot on the ground plane is presented. The proposed antenna structure is constructed in a planar form without a balun circuit and the radiation characteristics of conventional and eccentric spiral antennas are obtained simultaneously. The main beam direction is normal to the plane of the spiral for characteristic frequency band and the direction of the main beam moves linearly into
direction as the frequency increases.
Stabilization of an Adaptive Polynomial Predistorter
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 475~483
The new architecture for the stabilization of an adaptive linearizer using the RLS algorithm is presented. The delay lock loop is apl)lied to compensate the feedback loop delay of the nonlinear amplifier output, and the Yang's algorithm is used to mitigate the numerical unstability of the RLS algorithm. This method is applied to the linearizer using the polynomial predistorter, and it's efficacy is verified by the simulation of the proposed structure.
Voltage-Controlled PH Diode Attenuator and Temperature Compensation Circuit for Ku-band Satellite Payload
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 484~491
This paper presents the results of a study of voltage-controlled PIN diode attenuators for Ku-band satellite payload and suggests the temperature-compensation method of these attenuators. The PIN diode attenuators are designed using thin-film hybrid techniques. The load resistance for maximum linear characteristics is determined by simulation and measurements. In the case of APD0805, load resistance of 150
gives attenuator up to 10 dB linear attenuation range per a PIN diode. Also, measurements over temperature of these PIN diode attenuators were performed. From these measurements, designed PIN diode attenuators shows the severe temperature dependency due to forward voltage variation. A temperature compensation method using thermistor is now suggested to compensate the temperature variation of these PIN diode attenuators. This circuit shows good linear characteristics over wide temperature range
MTJ Performance Analysis of Hybrid DS/SFH Spread-Spectrum System using MSK or QPSK Modulation over Rayleigh Fading Channel
Ryu, Heung-Gyoon ; Chung, Byung-Ki ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 492~499
Performance analysis and comparison of the hybrid DS-SFH spread-spectrum (SS) system using coherent MSK and QPSK modulation techniques over Rayleigh fading channel are considered in the presence of MTJ(multi-tone jamming). To analyze the BER performance of the hybrid systems with or without the Rake receiver, signal-to-noise plus interference ratio is derived as a function of the average signal-to-noise ratio, the jammer-to-signal ratio and other system parameters. Numerical results show that the performance difference between the two modulation schemes, MSK and QPSK, is negligible for low JSR, while it becomes significant with the increase of JSR. In multi-path Rayleigh fading channel without Rake receiver, the performances of the two modulation schemes are slightly improved as the DS spreading gain is increased when the total SS bandwidth is fixed. In particular, there is an optimum DS spreading gain for large JSR, in which a minimum BER is achieved, while only DS spreading gives the best performance for small JSR. For hybrid systems with Rake receiver, it is shown that the hybrid system of the MSK modulation scheme provides better anti-jamming performance and larger performance improvement with the increase of multi-path resolution capability of Rake receiver than that of QPSK modulation for all conditions.
A Compact Rotman Lens with Wide Angle Steering Characteristics
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 13, issue 5, 2002, Pages 500~506
This paper presents a design of wide angle steering microstrip Rotman lens operating over broadband frequency range for Electronic Warfare equipments. It has a compact and simple structure which it is easy to manufacture repetitively. The lens is modelled as a 2-dimension planar circuit, the contour integral method is performed over entire lens contour and the transmission coefficients from 8 beam ports to 8 array ports are found. The measured results are well agreed with those of analysis. Prediction of the multibeam array pattern fed by linear array antenna shows
of beam steering and
5 dB insertion loss deviation over 3:1 frequency range.