• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.11 no.1
• /
• pp.64-72
• /
• 1986

The error rate equation fo DS-BPSK(Direct Sequence Binary Phase Shift Keying) signal transmitted through the nonlinear satellite transponder has been derived in the cochannel interference and downlink Gaussian noise environment. The input to the satellite transponder is the superposition of DS-BPSK signal with one interfere which is a cochannel wide-band PN signal. The error rate performance of DS-BPSK system has been evaluated and shown in figures in terms of carrier to interference power ratio(CIR), downlink signal to noise power ratio(downlink SNR) and process gain. In the analysis, it has been shown that the use of a hard limiter in DS-BPSK satellite system leads to the generation of narrow-band intermodulation products which is independent of the process gain. Also it is known that the error rate performance can be improved in the low levels (below 10dB) of CIR as the CIR increase. As the process gain varies from 10 to 100 the curve gives the about 10 dB gain in downlink SNR to maintain a fixed error rate.

• Journal of the Institute of Convergence Signal Processing
• /
• v.15 no.1
• /
• pp.9-14
• /
• 2014

The path loss data was re-calculated according to the distance between the base station and a mobile station in the mobile telecommunications network. In this paper, the averaged path loss data was plotted with the conventional path loss models(free space, plane earth, Hata model ${\ldots}$). The standard deviations for the 2 Km, 1 Km, 0.5 Km-interval averaged path loss were 2.29 dB, 3.39 dB, 4.75 dB, respectively. Additionally, the derivative values for the 2 Km, 1 Km, 0.5 Km-interval averaged path loss were evaluated to find the positions with more than 1 times or 2times of the standard deviation. The situations with the sharply fluctuated path loss were calculated to 5 positions in the 2 Km interval, to 7 positions in the 1 Km interval, to 19 positions in the 0.5 Km interval, respectively. And, the exact distances between the base station and a mobile station were found with the sharply fluctuated path loss.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2006.05a
• /
• pp.1377-1380
• /
• 2006

사회가 풍요롭고 생활수준이 높아짐에 따라 사람들은 자신의 건강상태에 신경을 많이 쓰고 있다. 또한 유비쿼터스 시대가 시작되면서 언제 어디서든 간단하고 편하게 건강 상태를 체크할 수 있는 시스템이 필요하게 되었다. 이 시스템은 일상생활에서 시간과 장소의 제약 없이 개인이 자신의 심박변이도 상태를 체크 할 수 있다. 보통 큰 병원에서나 사용 해야만 했던 부담감 대신 항상 스스로 자신의 건강상태를 확인하여 그 결과에 따라 맞게 대처 할 수 있다. 브레드 보드와 마이컴을 이용하여 SPO2 센서를 통해 들어온 신호를 PDA로 전송하고, 측정된 HRV(Heart Rate Variability : 심박변이도) 신호를 임베디드 시스템을 이용하여 PDA의 화면에 그래프로 나타내는 GUI 환경의 시스템이다.

• Journal of the Institute of Convergence Signal Processing
• /
• v.3 no.2
• /
• pp.89-95
• /
• 2002

Global routing is to assign each net to routing regions to accomplish the required interconnections. The most popular algorithms for global routing inlcude maze routing algorithm, line-probe algorithm, shortest path based algorithm, and Steiner tree based algorithm. In this paper we propose weighted network heuristic(WNH) as a minimal Steiner tree search method in a routing graph and a genetic algorithm based on WNH for the global routing. We compare the genetic algorithm(GA) with simulated annealing(SA) by analyzing the results of each implementation.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2015.04a
• /
• pp.1049-1050
• /
• 2015

e-health보드를 이용하여 측정한 생체신호를 실시간으로 블루투스통신을 통한 무선통신을 함으로서 PC와 연결한다. PC에서 송신된 데이터를 텍스트로 저장한 뒤 c#으로 체온, 심전도, 근전도, 피층 전기 반응, 호흡 5가지의 결과 값을 그래프로 보여준다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.10
• /
• pp.1483-1489
• /
• 2022

Recently, due to the influence of the 4th industrial revolution and the development of communication media, various digital video equipment are being used in industrial fields. Image data is easily damaged by noise in the process of acquiring and transmitting and receiving from the camera and sensor, and since the damaged image has a great effect on the processing of the system, noise removal is essential. In this paper, a weight filter algorithm using a weight graph is proposed to restoration images damaged by high-density impulse noise. The proposed algorithm obtains a weight graph using pixel values inside the filtering mask of the image, and restores the image by applying the final weight to the filtering mask. Simulation was conducted to analyze the noise removal performance of the proposed algorithm, and the magnified image and PSNR were used to compare with the existing method. The resulting image of the proposed algorithm showed excellent performance by removing high-density impulse noise.

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2006.06a
• /
• pp.13-16
• /
• 2006

사진을 찍을 때 카메라는 보기 좋은 사진을 얻을 수 있도록 많은 기능을 제공하고 있다. 대표적인 기능으로 자동 초점거리 조정(Auto Focus), 자동 색온도 보정(Auto White Balance), 자동 노출 조정(Auto Exposure)이 있다. 본 논문에서는 편리한 기능들 중 하나로써 자동 노출제어 시스템을 구현하였다. 본 논문에서 제안하는 자동 노출제어 시스템은 가변 시상수(Variable Time Constant)를 가지는 IIR 필터를 이용한다. Zone System에서 보여주는 사물의 휘도정보를 바탕으로 하여 이상적인 영상의 휘도 특성 그래프를 얻어내고, 이와 현재의 노출설정에서 휘도와 비교하여 적정 노출을 찾는다. 제안하는 자동 노출제어 시스템은 적정 노출을 얻을 수 있는 위치로 이동하기 위하여 기존의 마이크로 콘트롤러 등을 이용하여 구현하는 방법과 달리 간단한 구성을 가지는 IIR 필터를 이용한다. 제안하는 자동 노출제어 시스템은 간단한 구성을 가지므로 콤팩트 이미지 센서를 구성하기 위하여 사용 할 수 있다.

• Journal of the Institute of Convergence Signal Processing
• /
• v.6 no.1
• /
• pp.39-44
• /
• 2005

Scheduling for digital system synthesis is assigning each operation in a control/data flow graph(CDFG) to a specific control step without violating precedence relation. It is one of the most important tasks due to its direct influence on the performance of the hardware synthesized. In this paper, we propose a resource-constrained scheduling algorithm. Our algorithm first analyzes the given CDFG to determine the number of functional units of each type, then assigns each operation to a control step while satisfying the constraints. It also tries to improve the solution iteratively by adjusting the number of functional units using the results collected from the previous scheduling. Experiments were performed to test the performance of the proposed algorithm, and results are presented

• Journal of the Institute of Convergence Signal Processing
• /
• v.7 no.4
• /
• pp.201-206
• /
• 2006

Genetic Algorithms have been known to provide near optimal solutions for various optimization problems in engineering. In this paper, we study the effect of gene order in genetic algorithms on the defining length of the schema with high fitness values. Its effect on the performance of genetic algorithms was also analyzed through two well known problems. A few gene reordering methods were proposed for graph partitioning and knapsack problems. Experimental results showed that genetic algorithms with gene reordering could find solutions of better qualities compared to the ones without gene reordering. It is very important to find proper reordering method for a given problem to improve the performance of genetic algorithms.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2011.04a
• /
• pp.467-468
• /
• 2011

본 논문에서는 촉각전달장치를 기반으로 수식에 대한 그래프와 도형과 같은 시각교육정보들을 촉각 정보로 자동 변환하여 제공하는 프로그램을 구현하였다. 구현한 프로그램으로는 입력된 그래픽 정보를 촉각정보전달 장치의 해상도에 적합하게 다운샘플링(downsampling)을 수행한 후, 이진화(binarization)를 통해 촉각신호를 생성한다. 그리고 이를 촉각정보전달 장치에 전달하여 출력함으로써, 시각장애인들에게 그래픽 정보를 촉각정보로 변환하여 제공할 수 있다. 결과적으로 본 프로그램을 통해 수학 및 과학과 같은 이공계열의 교육정보를 편리하고 빠르게 촉각정보로 변환하여 시각장애인들에게 제공할 수 있었다.