• Title/Summary/Keyword: digital communication systems

Search Result 1,155, Processing Time 0.032 seconds

Image Enhancement Algorithm in Imaging Systems for Electronic Photography (전자사진용 화상시스템의 화상개선 알고리즘)

  • 박용주;김지홍
    • Journal of the Korean Graphic Arts Communication Society
    • /
    • v.20 no.1
    • /
    • pp.133-145
    • /
    • 2002
  • A study on electronic imaging system with silver halide photography emulation by a parametric approach will be introduced. The study contains the comparison analysis between silver halide imaging process and electronic imaging process, the characterization of the detailed process in those imaging chains, such as exposure, developing, photographic print and the other photographic and digital process. We investigated the characteristic curve between optical density and the amount of exposure in silver halide and digital photography systems. Under wide range of exposure condition, several sensitometric parameters were obtained via studio and outdoor photographic experiments with conventional photography and a digital camera. whose experimental results will be shown. Finally, the comparison between electronic imaging and conventional photography via silver halide photography emulation and modeling the silver halide process wi13 be discussed.

  • PDF

A Case Study on Foreign Intelligent Transport System (지능형 교통 시스템의 해외 사례 연구)

  • Lee, Dong-Woo
    • Journal of Digital Convergence
    • /
    • v.12 no.6
    • /
    • pp.259-264
    • /
    • 2014
  • Digital convergence means a service or new product which appeared through fusion of unit technologies in information and communication regions. In 2011, The Government introduced "IT Convergence Technology Prediction Survey 2025". Smart mobility is a main factor in smart city which is main example of convergence. A intelligent transport system(ITS) is a key factor of smart mobility. The conventional transport systems include road, car, signal systems. But the ITS is a transport system containing additional technologies such as electronics, control, communication to increase traffic safety and effectiveness of traffic facilities. In this paper, we described intelligent transport system related with our life.

Implementation of QPSK Modem using TMS320C31 (TMS320C31을 이용한 QPSK 모뎀 구현)

  • 김광호;김종욱;조병모;김영수
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.12 no.5
    • /
    • pp.817-826
    • /
    • 2001
  • In this paper, we implemented QPSK(Quadrature Phase-Shift Keying) modem which is widely used for communication systems, using a general Digital Signal Processor(DSP), TM320C31. Up to now, almost all of communication systems consist of hardware. However, the implemented system herein is composed of software and hardware part. Software part includes the modulation process, before passing D/A(Digital-to-Analog Converter) and the demodulation process, after passing A/D(Analog-to-Digital Converter) in IF(Intermediate Frequency) node. Hardware part is related to input, output and process of signal. To demonstrate the successful implementation of modem, the output results obtained from DSP processor are compared with the simulated result on the personal computer.

  • PDF

A study on the digital image transfer application mass chest X-ray system up-grade (간접촬영기의 디지털 영상 변환 장치 적용에 대한 연구)

  • Kim, Sun-Chil;Park, Jong-Sam;Lee, Jon-Il
    • Journal of radiological science and technology
    • /
    • v.26 no.3
    • /
    • pp.13-17
    • /
    • 2003
  • By converting movable indirect mass chest X-ray devices for vehicles into digital systems and upgrading it to share information with the hospital's medical image information system, excellencies have been confirmed as a result of installing and running this type of system and are listed hereinafter. 1. Upgrading analog systems, such as indirect mass chest X-ray devices dependent on printed film, to digital systems allows them to be run and managed much more efficiently, contributing to the increase in the stability and the efficiency of the system. 2. Unlike existing images, communication based on DICOM standards allow images to be compatible with the hospital's outer and inner network PACS systems, extending the scope of the radiation departments information system. 3. Assuming chest-exclusive indirect mass chest X-rays, a linked development of CAD (Computer Aided Diagnosis, Detector) becomes possible. 4. By applying wireless Internet, Web-PACS for movable indirect mass chest X-ray devices for vehicles will become possible. Research in these fields must continue and if the superior image quality and convenience of digital systems are confirmed, I believe that the conversion of systems still dependent on analog images to modernized digital systems is a must.

  • PDF

Performance Study of Multicore Digital Signal Processor Architectures (멀티코어 디지털 신호처리 프로세서의 성능 연구)

  • Lee, Jongbok
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.13 no.4
    • /
    • pp.171-177
    • /
    • 2013
  • Due to the demand for high speed 3D graphic rendering, video file format conversion, compression, encryption and decryption technologies, the importance of digital signal processor system is growing rapidly. In order to satisfy the real-time constraints, high performance digital signal processor is required. Therefore, as in general purpose computer systems, digital signal processor should be designed as multicore architecture as well. Using UTDSP benchmarks as input, the trace-driven simulation has been performed and analyzed for the 2 to 16-core digital signal processor architectures with the cores from simple RISC to in-order and out-of-order superscalar processors for the various window sizes, extensively.

Digital Leveraging: The Methodology of Applying Technology to Human Life (디지털 레버리징: 기술을 인간의 삶에 적용하는 방법론)

  • Han, Sukyoung;Kim, Hee-Cheol;Hwang, Wonjoo
    • Journal of Korea Multimedia Society
    • /
    • v.22 no.2
    • /
    • pp.322-333
    • /
    • 2019
  • After the launch of smart phones, various miniaturized smart devices such as wearable and IOT devices have deeply embedded in human life, and have created a technology-oriented society. In this technology-oriented society, technology development itself is important, however it seems more important to utilize existing technology appropriately and deliver effectively to human life. As the computer became personalized after the appearance of PC, human-centered computing such as HCI and UCD had begun to appear. However, most of the researches focused on technology that made human being convenient to interact with computer such as computer systems design and UX development. In the technology-oriented society, it seems more urgent to apply existing technology to human life. In this paper, we propose a methodology, 'Digital Leveraging' which guides how to effectively apply technology to human life. Digital Leveraging is the way of convergence between technology and humanities.

High-performance Mobile Transmission Rate and Physical Layer Linear Error Correction Performance Verification (고성능 모바일의 전송율 향상을 위한 무선 통신 시스템의 물리계층 선형에러 성능 검증)

  • Chung, Myungsug;Lee, Jooyeoun;Jeong, Taikyeong
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.22 no.3
    • /
    • pp.19-26
    • /
    • 2017
  • In this paper, a Linear Error Correction Code, Which is Applicable to Next Generation Wireless Communication System Technology, is Constructed Based on Performance Comparison and Transmission Based on the Premise of High Performance Mobile Rate Enhancement System. This is Because Data Rates are Becoming an Important Issue in Reed-Solomon Codes and Linear Error Code (LDPC) Used in the Physical Layer of Digital Communication and Broadcasting Technologies. Therefore, this paper Simulates the Performance of Reed - Solomon Code and LDPC Applied to Mobile Broadcasting DVB (Digital Video Broadcasting) System and Mobile Broadcasting in Digital Communication and Broadcasting, At this time, Technical Aspects of the Transmission Efficiency and Performance of the LDPC Replacing the Existing Reed-Solomon Code have been Verified from the Viewpoint of Efficiency.

Control of Inverted Pendulum Using Continuous Time Deadbeat Control

  • Lee, Ho-Jin;Kim, Seung-Youal;Lee, Jung-Kook;Kim, Jin-Yong;Lee, Seung-Hwan;Lee, Keum-Won;Lee, Jun-Mo
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.510-513
    • /
    • 2005
  • Due to the asymptotic property, deadbeat control can hardly be applied to the continuous time system control. But some delay element method can deal such a problem. Besides delay element method, well-known digital deadbeat control can be used by the aid of some smoothing elements. In this paper, 2nd order smoothing element is used for the smoothing of the digital deadbeat controller. And this element is argumented to the plant, and so control problem is to control the argumented system digitally. We simulated this control system using Matlab language and finally apply this algorithm to the rotary inverted pendulum system.

  • PDF

A Study on Policy Making for e-Navigation from the Viewpoint of a Maritime Digital Communication Network (e-Navigation을 위한 해상디지털통신 구축에 관한 정책 연구)

  • Lim, Hyuntaek;Cho, Yong-Gab
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.24 no.6
    • /
    • pp.679-685
    • /
    • 2018
  • In order to reduce marine accidents using advanced information and communication technology, various research and development projects are conducted globally on e-Navigation related technologies and services. Existing studies do not provide policy measures for LTE-M. In order for these technologies and services to be installed on vessels and to contribute to the prevention of accidents at sea, the law should be expand operational organizations and systems. In particular, communication equipment and related technical standards should be prepared, and its digital communication technology (LTE-M, VDES, Digital-MF / HF, etc.) In this study, we conducted short, medium, and long term performance assessment of the identification system and the policy for effective implementation of Korean e-Navigation. We presented a visible plan of the relevant policy. For example, e-Navigation core services, e-Navigation communication networks and operating systems, e-Navigation international standard leading technologies and e-navigation services activated in the field. To do this, we conducted research based on the progress data of the Korean e-Navigation project, which was led by the Ministry of Maritime Affairs and Fisheries, and conducted research discussions with practitioners and experts in related fields. As a result of this study, it is expected that the proposed policies will contribute to the reduction of marine accidents, the promotion of the maritime industry and the development of additional government policies for national security.

Analysis and Proposal of Communication System for Maritime HF Band Digital Data Exchange (해상 HF대역 디지털 데이터 교환을 위한 통신시스템 분석 및 제안)

  • Choi, Sung-Cheol;So, Ji-Eun;Park, Hyung-Chul
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.21 no.12
    • /
    • pp.2249-2260
    • /
    • 2017
  • IMO (International Maritime Organization) has been providing GMDSS (Global Maritime Distress and Safety System) and mandating to install distress and safety systems according to SOLAS. Digital-HF(High-Frequency) coast station communication system maintains interoperability between ship and coast station and digital data exchange in maritime mobile service by digitizing existing analog base voice communication. In this paper, we analyze ITU-R M. 1798-1 established by ITU for digital HF communications and propose Advanced annex2 and new Annex 5 to improve the problems of the existing Annex 2 and Annex 4. The proposed OFDM protocol basically adopts ARQ (Automatic Retransmission Request) which retransmits when an error occurs in a half-duplex manner between an information transmitting side (ISS) and an information receiving side (IRS) and we propose a digital HF communication system and its operational concept which is more reliable and superior than the existing ITU-R M. 1798 by implementing technical development on implementation and performance improvement.