• Korean Journal of Remote Sensing
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• v.26 no.4
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• pp.439-449
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• 2010

This paper reports experiments and analysis work done to find out the cause of Y parallex for stereo pairs of KOMPSAT-2 images and means to improve the Y parallex problem. We could conclude that the Y parallex problem was caused by resampling errors of KOMPSAT-2 PANchromatic bands, induced by the process of warping PANchromatic band with reference to multispectral bands. We could also conclude that a rigorous warping process could improve resampling of KOMPSAT-2 PANchromatic band and remove the Y parallex problem significantly. We also confirmed that a rigorous warping process could also remove blocky brightness patterns present on KOMPSAT-2 PANchromatic band. Therefore, by implementing more rigorous warping process within KOMPSAT-2 scene generation procedures, KOMPSAT-2 geometric and radiometric quality will be improved.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.1
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• pp.9-15
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• 2017

In this study we performed the experiment to detect the ERP using SVM with wavelet features. The EEG signal that is generated visual stimulated ERP database in SCCN applied for the experiment. The feature vectors for experiment are categorized frequency and continuous wavelet- based vectors. In experimental results, the detection rate of SVM with wavelet feature vectors improved above 10% comparing with frequency- based feature vector. Based on the experimental results we analyzed the relation between the activity degree of the ERP and the band split characteristics of the ERP by wavelet transform.

• The Journal of the Acoustical Society of Korea
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• v.23 no.2
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• pp.134-145
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• 2004

The study aims to develop the underwater wireless telephone system. The system is designed based on the underwater acoustic communication channel parameters such as ambient noise, multipath effect and diver breathing noise. The system adopts SSB modem and its carrier frequency is about 33 kHz in which ambient noise level is low and therefore a high S/N ratio is easily obtained. The source level of the transmitter is designed as 131 dB re 1μPa. Its intelligibility index of sentence shows as 80% or mure in the range of less than 300m in the sea trial.

• The Journal of Information Technology
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• v.6 no.4
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• pp.81-91
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• 2003

This paper is concerned with the implementation of power line communication system with 9.6Kbps. This system is suitable to establish the smart home using the power line having been installed in house. In the suggested power line communication system, we use the chirp signal with a linearity and spread spectrum frequency band of 100KHz~200KHz. We had the performance experiment for the implementation system. The experiment was achieved in the pseudo load network similar to real circumstance of power line communication. As the result, the communications under the circumstance were accomplished satisfactorily. We confirmed that the suggested 9.6Kbps power line communication system with the Chirped-SS method had the performance enough to commercialize the smart home.

• The Transactions of the Korean Institute of Power Electronics
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• v.5 no.6
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• pp.632-637
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• 2000

In this paper, to control with light dimming levels of the fluorescent lamps, we have used the power line instead of the signal line to transmit the control signals. To reduce the BER(Bit Error Rate) on the power line communication with the serious noise interferences. We have adapted the FSK(Frequency Shift Keying) modulation and demodulation technique. Since the electronic ballast produced the EMI(ElctroMagnetic Interference) noise in some frequency bands, we have reduced the EMI levels in the band below -50dB. By varying the switching frequency of the ballast for the FL032/T8 from 18kHz to 25kHz, it is possible that the dimming levels are controled with the range of 5∼100%

• Journal of Korean Society for Geospatial Information Science
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• v.16 no.3
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• pp.71-78
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• 2008

Nowadays, echosouder has been widely used in sea survey and ship navigation. By utilizing echosounder, we can measure the depth of water reliability. However, the problem is that depth update rate drops remarkably when sea bottom is shallow or steep/rugged. Therefore, we have developed an optimized algorithm to process tranducer's soundwave signals at high-speed and minimize error. Processing algorithm is implemented by the latest DSP processor (TMS320F2812), consequently, high-speed data processing can be achieved. Performance of the proposed algorithm is verified by experiments and compared with existing algorithms. It has shown that our method results in higher precision in water depth measurement than other methods.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.3
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• pp.309-315
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• 1998

This paper is analyzed the performance of coded MC-CDMA system using the multi-carrier with narrow band that is suggested to solve ISI and ICI of DS-CDMA system. In this paper, considered channel model is indoor mobile radio communication environment with Rician fading distribution and fading of multi-carrier have mutual independent characteristics. For the performance analysis of MC-CDMA system, first, bit error probability of uncoded system is simulated in the reverse and forward Rician channels. And then, it is simulated that bit error probability of coded MC-CDMA system for users, multicarriers and SNR, using (7,4) Hamming code, (15,7) BCH code and 1/2-convolutional code with 7 constraint length.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.4
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• pp.686-691
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• 2012

Deviating from the exclusive frequency assignment, UWB has utilized much wider frequency range, worked independently without interfering other frequencies, and simultaneously enabled to increase more than hundreds of Mbps data transmission rate. In considering its high data rate and no interference, UWB certainly has an infinite and technical potential. In this paper, we studied the UWB technology as well as its technological trend, analyzed UWB antenna, and actualized a small antenna for wireless video streaming devices.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.296-299
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• 2003

In this paper, an underwater acoustic digital transceiver is designed and implemented by a multiple DSPs system. We have designed a QPSK transmitter based on look-up table and 13-symbols Barker code is used for frame synchronization. Channel distortions are compensated by a wide-band beamformer based on FIR filter and an adaptive equalize. with RLS algorithm. Uniform linear array (ULA) with four elements is used for the spartial signal processing. 1/2 convolutional code and Viterbi decoder are implemented to overcome time-varying multi-path fading. Also, we show experimental results in the underwater anechoic basin at KRISO/KORDl and Goseong, Donghae and Soyang lake of Kangwon-do.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.2
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• pp.60-65
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• 2009

A highly reliable Video Transmission System (VTS) was developed in order to obtain both video and digital data simultaneously in the real time flight test situation of a flying vehicle. The VTS integrates GPS date digital telemetry data and video signals into a compact digital data package which is compressed and processed by an MPEG-2 Encoder and a modulator respectively. The modulator is composed of a specially devised Forward Error Correction processor and base band QPSK modulator. The designed VTS was verified and proved for its required functioning and performance through separate flight tests using an airplane and Rockets.