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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Journal of Korean Institute of Communications and Information Sciences
Journal Basic Information
Journal DOI :
The Korean Institute of Communications and Information Sciences
Editor in Chief :
Kwang Soon Kim
Volume & Issues
Volume 13, Issue 6 - Dec 1988
Volume 13, Issue 5 - Oct 1988
Volume 13, Issue 4 - Aug 1988
Volume 13, Issue 3 - Jun 1988
Volume 13, Issue 2 - Apr 1988
Volume 13, Issue 1 - Feb 1988
Selecting the target year
A Fundamental Study on the Receiver Front-End of Satellite Communication
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 277~284
A 12GHz low-noise amplifier, a single gate GaAs MESFET mixer, and a low-pass filter have been fabricated for DBS receiver applications by using MIC technology. Each subsystem contains DC block with symmetric line and ship capacitor, respectively. The frequency converter with chip capacitor exhibits a 20-23 dB conversin gain with a RF bandwidth of 11.581-11.981 GHz and an IF bandwidth of 581-981MHz. Rf bandwidth of 12.1GHz and an IF banewidth of 1GHz.
The Performance Analysis of Multi-Level Quadrature Partial Response Signaling System
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 285~301
The symbol error rate equations of multi-level quadrature PRS(QPRS) system have been derived in the individual and composite environment of Gaussian/impulsive noise, cochannel CW interference, carrier offset, phase jitter and fading. And using the derived error rate equations, the probability of error has been evaluated and shown in graphs as functions of carrier to noise power ratio, carrier to interference power ratio, phase error, impulsive index, the ration of Gaussian noise to impulsive noise power component, signal to noise power ration in phase locked loop(PLL), and fading figures. The rseults show that the error rate performances are generally more more degraded by impulsive noise than by Gaussian noise. But on the contrary the erors occurred more frequently by Gaussian noise than impulsive noise in a fading environment.
Fast Codebook Search for Vector Quantization in Image Coding
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 302~308
The paper describes a very simple algorithm for reducing the encoding complexity of vector quantization(VQ), exploiting the feature of a vector currently being encoded. A proposed VQ of 16(=4x4) vector dimension shows a slight performance degradation of about 0.1-1.9dB, however, with only 16-32 among 256 codeword searches, i.e., with just 1/16-1/8 search complexity compared to a full-search VQ. And the proposed VQ scheme is also compared to outperform tree-search VQ with regard to their SNR performance and memory requirement.
A Representation of the Nonlinear Axis in the G. C
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 309~321
This paper proposes on the algorithm of axis equation & radius function for the G.C representation which describes the curved objects with circular cross section. Object combined with linear and nonlinear parts is detached by clustering from depth data & axis points is extracted by normal vecter of the surface mask patches. In ths case of nonlinear axis point, axis equation is described by Hermite curve & the effectiveness of this paper is demonstrated by serveral experiments.
An Active filter Design using Normalized High Order Inverse Chebyshev Functions
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 322~331
In this thesis, an active RC filter using high order inverse chebyshev function is designed and the design method for cascading blocks with low sensitivity and maximum dynamic range is discussed. To have maximum dynamic range, we have proposed the simple algorithm with a pole-zero pairing, the cascading sequence by flatness matrix and optimum gain distribution for a given transfer function. And 2nd order Block is designed with negative feedback to improve the sensitivity problem which had a defect at active RC circuits. Using the suggested method, we have designed the active RC low pass filter of the normalized 7th order inverse chebyshev function, as a results, we have shown that this accord with the given specification.
Weak Random Signal Detection:In Signal-Dependent Noise
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 332~339
Using a generalized observation model, in which one can express the effects of non-additive noise such as signal-dependent noise and multiplicative noise in addition to purely-additive noise, the problem of weak random-signal detection is investigated. It is shown that the test statistics of locally optimum detectors for detection of weak random signals in signal-dependent noise model are interesting extensions of those in purely-additive noise model. This result is a complement to the result for weak random-signal detction in multiplicative noise model.
Adaptive Control of a Robot Manipulator in Operational Space
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 340~351
Up to now, hybrid torque/position control of robot manipulator have been researched under the assumption that link mass and/or load are known. This paper proposes a torque and position control method under unknown mass of links or load of a robot manipulator and the method extend control in joint space to control in operational space. In the method, known parameters are used to estimate unknown parameter. We illustrate the theory with some simulations and show that the result is effective.
A Study on the Discrete Time Parameter Adaptive Learning Control System
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 352~359
A learning control system which should have memory elements can be designed by utilizing the concept of parameter adaptation for unknown control object system parameters and regard it as a hybrid adaptive control system. A parameter adaptive learning control system applicable to a continuous time system has been already reported. Since there have been rapid developments in digital technology, it is possible to extend a continuous time parameter adaptive learning control system concept to a discrete time case. This problem is treated in this paper. Its justfication is proved and a simulation shows that this algorithms is effective.
Design of 14-14.5GHz Band Low Noise GaAsMESFET MIC Amplifier
The Journal of Korean Institute of Communications and Information Sciences, volume 13, issue 4, 1988, Pages 360~368
A 14 to 14.5 GHz low noise MIC amplifier is designed on the
substrate. The amplifier which uses a GaAsMESFET developed at COMSAT Laboratories has been designed and optivized to have gain greater than 7dB and noise figure less than 2dB using Super-Compact program. Experimental results show that the gain of the amplifier is 7 to 7.7 dB, while noise figure is 3.8 to 4.3dB through the desired band.