• Title/Summary/Keyword: digital communication system

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Design of Synchronized Power Control Embedded System Based on Core-A Platform (Core-A 플랫폼을 이용한 동기형 전력제어 임베디드 시스템 설계)

  • Lee, Woo-Kyung;Moon, Dai-Tchul
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.6
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    • pp.1413-1421
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    • 2014
  • This paper realize power control embedded system with one master of Core-A 32-bit RISC processor and several slaves controling power with synchronized digital signals. Core-A platform is consisted of Core-A processor, AMBA bus, SSRAM, AC97, DMA, UART, GPIO etc. Slave is made by both digital part and analog part. The former generates various power control patterns synchronized with master signal. The latter converts 220V power proportional to 4 bit digital signals. design of Embedded system is executed in Flowrian II, in which software is cross-compiled and hardware is verified by simulation. Embedded system is implemented in FPGA board and CPLD chips as well as PCB board for analog power control.

A study on a digital load cell for the removal of load cell noise (Load Cell Noise 제거를 위한 Digital Load Cell 에 대한 연구)

  • Lee, Young-Jin;Lee, Heung-Ho
    • Proceedings of the KIEE Conference
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    • 2002.11c
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    • pp.562-564
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    • 2002
  • Noise reduction and a simplification of a precision measurement system has been performed by changing analog output mode of a load cell into digital output mode. Usually, analog output signal of a few $\mu V$ from a load cell are amplified by amp and acquired by A/D converter. If the distance from a load cell to a DAS(Data Acquisition System) increases, more noise signals are mixed. So, a microprocessor has been integrated into a load cell so that the amplification and A/D conversion of output signals could be done in close proximity to the lode cell for the reduction in mixing of noise. Obtained data from the load cell like this manner are transferred to a computer with digital values(of TTL level). To simplify the configuration of a multi-channel DAS, RS-485 communication system has used for data transfer.

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Medical Digital Twin-Based Dynamic Virtual Body Capture System (메디컬 디지털 트윈 기반 동적 가상 인체 획득 시스템)

  • Kim, Daehwan;Kim, Yongwan;Lee, Kisuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.10
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    • pp.1398-1401
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    • 2020
  • We present the concept of a Medical Digital Twin (MDT) that can predict and analyze medical diseases using computer simulations and introduce a dynamic virtual body capture system to create it. The MDT is a technology that creates a 3D digital virtual human body by reflecting individual medical and biometric information. The virtual human body is composed of a static virtual human body that reflects an individual's internal and external information and a dynamic virtual human body that reflects his motion. Especially we describe an early version of the dynamic virtual body capture system that enables continuous simulation of musculoskeletal diseases.

Channel Allocation Method of DAB System considering National SFN (전국 SFN을 고려한 DAB 시스템의 채널 배치 방안)

  • Ju, Sang-Lim;Yang, Kyu-Tae;Lim, Hyoungsoo;Kim, Kyung-Seok
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.95-103
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    • 2015
  • The Korea terrestrial broadcasting has TV and Radio, DMB. The TV broadcasting was converted from the analogue method to the digital method at the end of 2012. However the radio broadcasting is still in analogue method. The introduction of digital radio technology will bring many benefits such as high-quality of sound, various additional services and increase of efficiency in frequency utilization. In many countries, the radio broadcasting is been servicing in digital method. The discussion was begun on this year for the introduction of digital radio technology in Korea. So, to prepare against introduction of DAB system among digital radio technology, this paper proposes channel allocation method for each local radio broadcasting and the composition of national SFN, and proves the proposed method through the interference analysis.

A Review of Assistive Listening Device and Digital Wireless Technology for Hearing Instruments

  • Kim, Jin Sook;Kim, Chun Hyeok
    • Korean Journal of Audiology
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    • v.18 no.3
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    • pp.105-111
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    • 2014
  • Assistive listening devices (ALDs) refer to various types of amplification equipment designed to improve the communication of individuals with hard of hearing to enhance the accessibility to speech signal when individual hearing instruments are not sufficient. There are many types of ALDs to overcome a triangle of speech to noise ratio (SNR) problems, noise, distance, and reverberation. ALDs vary in their internal electronic mechanisms ranging from simple hard-wire microphone-amplifier units to more sophisticated broadcasting systems. They usually use microphones to capture an audio source and broadcast it wirelessly over a frequency modulation (FM), infra-red, induction loop, or other transmission techniques. The seven types of ALDs are introduced including hardwire devices, FM sound system, infra-red sound system, induction loop system, telephone listening devices, television, and alert/alarm system. Further development of digital wireless technology in hearing instruments will make possible direct communication with ALDs without any accessories in the near future. There are two technology solutions for digital wireless hearing instruments improving SNR and convenience. One is near-field magnetic induction combined with Bluetooth radio frequency (RF) transmission or proprietary RF transmission and the other is proprietary RF transmission alone. Recently launched digital wireless hearing aid applying this new technology can communicate from the hearing instrument to personal computer, phones, Wi-Fi, alert systems, and ALDs via iPhone, iPad, and iPod. However, it comes with its own iOS application offering a range of features but there is no option for Android users as of this moment.

A Study on the Development of an Unmanned Marine probing Ship (소형 무인 해양탐사선 개발에 관한 연구)

  • 김상철;임종환;강철웅
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.312-315
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    • 2003
  • The paper presents a small. unmanned remote controlled probing ship that can reduce the cost for acquiring data of marine and coastal environments. The control system is composed of three microprocessors. one is for overall mission control. another for control of propulsion motors. and the other for sensor operation. For communication system, we adopt direct and indirect methods based on the wireless modem of commercial cellular telephone. The former is a direct communication between the modems of the ship and the server. and the latter is an indirect communication via internet between the ship and the server. The system is equipped with a digital compass and a GPS system for position estimation, and extended Kalman filter is used for the data association. The performance of the ship is demonstrated with the results produced by sets of experiments.

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Development of Current Control System for Solar LED Street Light System

  • Kim, Byun-Gon;Kim, Kwan-Woong;Jang, Tae-Su;Lee, Jun-Myung;Kim, Yong-Kab
    • International journal of advanced smart convergence
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    • v.1 no.1
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    • pp.52-56
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    • 2012
  • As inexhaustible clean energy, solar energy will be the most ideal green energy in the 21st century. The effective method to convert solar energy into electrical energy is by solar photovoltaic power generation technologies. LED Emitting Diode is a kind of component which can transform electricity into visible light. As the smart current control system for photovoltaic street lights, the proposed system has improved the battery charging and discharging mechanism to extend the lifespan and effectively controls the LED discharge current according to battery charge state and lighting.

Digital Down Converter System improving the computational complexity (복잡도를 개선한 Digital Down Converter 시스템)

  • Moon, Ki-Tak;Hong, Moo-Hyun;Lee, Joung-Seok;Kim, Kyung-Seok
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.3
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    • pp.11-17
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    • 2010
  • Multi-standard, multi-band, multi-service system to ensure a flexible interface between the SDR (Software Defined Radio) technology for the implementation of the Stability and Low-Power, Low-Calcualrion DDC (Digital Down Conversion) technology is essential. DDC technology consists of a digital channel filter. This is a typical digital filter because of the limited fisheries are vulnerable to overflow and rounding errors are drawbacks. In this paper, we overcome this disadvantage, we propose the structure of the DDC. The way WDF (Wave Digital Filter) Structural rounding error due to the structural resistance to noise. Therefore, This is the useful structure when the filter coefficients's word length is short. In addition, since IIR filters based on FIR filters based on the amount of computation is reduced because fewer than filter's tap. The proposed structure is used in DDC that CIC (Cascaded Integrator Comb) filter, WDF, IFOP (Interpolated Fourth-Order Polynomials) were analyzed with respect to, the results were confirmed by computer simulation.

A Study of Digitalizing Analog Gamma Camera Using Gamma-PF Board (Gamma-PF 보드를 이용한 아날로그 감마카메라의 디지털화 연구)

  • Kim, Hui-Jung;So, Su-Gil;Bong, Jeong-Gyun;Kim, Han-Myeong;Kim, Jang-Hwi;Ju, Gwan-Sik;Lee, Jong-Du
    • Journal of Biomedical Engineering Research
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    • v.19 no.4
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    • pp.351-360
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    • 1998
  • Digital gamma camera has many advantages over analog gamma camera. These include convenient quality control, easy calibration and operation, and possible image quantitation which results in improving diagnostic accuracies. The digital data can also be utilized for telemedicine and picture archiving and communication system. However, many hospitals still operate analog cameras and have difficult situation to replace them with digital cameras. We have studied a feasibility of digitalizing an analog gamma camera into a digital camera using Gamma-PF interface board. The physical characteristics that we have measured are spatial resolution, sensitivity, uniformity, and image contrast. The patient's data obtained for both analog and digital camera showed very similar image quality. The results suggest that it may be feasible to upgrade an analog camera into a digital gamma camera in clinical environments.

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Solution to remove High Interference Areas using DRM+ in DAB Environment (DAB 환경에서 DRM+를 활용한 고 간섭지역 해결 방안)

  • Kim, Young-Jae;Lee, Byoung-Jin;Kim, Kyung-Seok;Choi, Ik-Kwon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.4
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    • pp.79-86
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    • 2015
  • Recently, broadcasting environment is dramatically changed due to adopt digital method in broadcasting technology. numerous country is adopting technology for converting analog to digital. However, in the case of South Korean, standard is still indefinite. In this paper, when it broadcast using DAB system, in oder to avoid interference caused by the frequency resource shortage, DAB system is substituted narrow bandwidth DRM+ system. Therefore it considers the way that solve interference. Interference analysis simulation result shows to solve high interference area in DAB environment