• Title/Summary/Keyword: broadcasting channel

검색결과 950건 처리시간 0.023초

농수산식품 전문채널 설립방안 - 농수산 마케팅 전문가, 농수산업인, 방송전문가 FGI 결과 - (A Plan to Establish Agriculture and Fisheries Special Channel - Marketing Expert, Farmer and Fisher, Broadcasting Expert FGI Result -)

  • 박지섭;문정훈;김진기
    • Agribusiness and Information Management
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    • 제2권1호
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    • pp.15-29
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    • 2010
  • Recently, IPTV population is growing by leaps and bounds. and We performed FGI(Focus Group Interview) with various experts related to agriculture field to establish Agriculture and Fisheries special channel. this growth has social background that is change of paradigm caused by the convergence of broadcasting, demand for Agriculture and Fisheries special channel using new media thanks to interests in Wellbeing, Green food. so we think that we need to consider the way to establish Agriculture and Fisheries special channel and its validity from all angles. that is why we are having a heated discussion with Agriculture and Fisheries marketing experts, farmer, fisher(Korean Cyber Farmer Association), broadcasting experts. Concretely, government budget is needed to establish Agriculture and Fisheries special channel, so we are just about to examine its validity and find business model. to make this discussion detailed, we made 4 subjects. First, Do we need agro-fishery products distribution channel using media? Second, After establishing of Agriculture and Fisheries special channel, how many demands will occur? Third, Should we make Agriculture and Fisheries special channel public channel? Fourth, What would be profit model of Agriculture and Fisheries special channel?

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ATSC 지상파 디지털 TV 방송의 단일 주파수 망 구성을 위한 등화형 디지털 동일 채널 중계기 (Equalization Digital On-Channel Repeater for Single Frequency Network Composition of ATSC Terrestrial Digital TV Broadcasting)

  • 박성익;음호민;이용태;김흥묵;서재현;김형남;김승원
    • 방송공학회논문지
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    • 제9권4호
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    • pp.371-383
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    • 2004
  • 본 논문에서는 단일 주파수 망(Single Frequency Network: SFN)을 통해 ATSC(Advanced Television Systems Committee) 지상과 디지털 TV 방송을 서비스하기 위해 필요한 기술적인 요구 사항에 대하여 고찰하고, 기존 디지털 동일 채널 중계기(Digital On-Channel Repeater: DOCK)가 가지는 단점을 극복한 등화형 동일 채널 중계기(Equalization Digital On-Channel Repeater: EDOCR)를 제안한다. EDOCR은 오류정정(Forward Error Correction: FEC) 복호 및 부호화부를 사용하지 않기 때문에 모호성(ambiguity) 문제가 발생하지 않아서 EDOCR의 입력 신호와 출력 신호가 동일하며, 고성능 등화기를 사용하여 주송신기와 EDOCR 사이의 전송로에 의해 야기된 잡음 및 다중경로 신호를 제거하므로 EDOCR 출력 신호의 품질이 입력 신호 보다 우수하다. 또한 낮은 안테나 격리도(isolation)로 인해 야기된 궤환(feedback) 신호를 EDOCR 등화기에서 제거할 수 있기 때문에 송신 출력을 높일 수 있다.

대화 채널을 이용한 양방향 방송 시스템의 구현 (Implementation of Bi-directional Broadcasting System Using Interaction Channel)

  • 정종면;최진수
    • 한국정보통신학회논문지
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    • 제9권5호
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    • pp.1002-1011
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    • 2005
  • 본 논문에서는 방송 프로그램에 시청자가 대화 채널을 이용하여 참여할 수 있도록 하기 위한 양방향 방송 시스템 즉, 리턴채널서버를 설계, 구현한다. 방송 프로그램에 시청자의 의견이나 응답을 실시간 반영하는 서비스를 제공하기 위한 리턴채널서버는 제어 모듈, 네트웍 인터페이스 모듈, 데이터베이스 관리 모듈, 그리고 실시간 콘텐츠 저작 모듈 등으로 구성된다. 이때 방송 서비스에 무관한 형태로 리턴채널서버를 구성하기 위하여, 본 논문에서는 리턴채널서버의 각 모듈들을 리턴채널서버 응용과 리턴채널서버 응용 실행 환경 등으로 계층적으로 구성한다. 리턴채널서버 응용은 실행코드와 실행코드의 실행에 필요한 파라메터로 구성되어 있으며, 리턴채널서버가 특정 방송 프로그램을 제공하기 위해 처리해야 하는 절차들을 정의한다. 한편 리턴채널서버응용 실행환경은 리턴채널서버 응용이 실행되기 위한 환경을 제공한다. 리턴채널서버를 리턴채널서버 응용 실행환경과 리턴채널서버 응용으로 계층적으로 구성하면, 방송 서비스 제공자가 제공하고자 하는 방송 서비스에 무관하게 리턴채널서버가 동작하도록 리턴채널서버를 구성할 수 있으며 이는 실험을 통해 확인되었다.

MATHEMATICAL MODELING OF VSB-BASED DTV CHANNELS

  • Kim, Hyoung-Nam;Lee, Yong-Tae;Kim, Seung-Won
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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    • pp.305-308
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    • 2001
  • We analyze mathematically a VSB (vestigial side-band) transceiver system for the Advanced Television Systems Committee (ATSC) digital television standard and extract a near-baseband equivalent VSB channel model. This model shows the multi-path fading effect of the quadrature component on the in-phase component. Also, we obtain a simplified model of the VSB transceiver system, which is represented by convolution of the transmission signal (before modulation) and the VSB channel. This simplified model is efficiently used for simulation of VSB systems to improve its performances, especially in an equalization part. Applying the DTV channel specifications tested by the Advanced Television Test Conter (ATTC) to the channel model, we obtain an equivalent VSB channel and show the equalization result by using the conventional derision-feedback equalize (DFE).

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MF 대역 디지털 라디오 방송 시스템을 위한 채널 추정 기법의 성능분석 (Performance Analysis of Channel Estimation Schemes for MF Band Digital Radio Broadcasting System)

  • 송정훈;김기남;노재성;조성준
    • 한국전자파학회:학술대회논문집
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    • 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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    • pp.599-603
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    • 2003
  • In this paper, the efficient channel estimationschemes for DRM system(AM band digital radio broadcasting standard) are investigated. In frequency domain, by means of the linear interpolation, the second order interpolation, cubic spline interpolation, and time domain interpolation, the channel impulse response is estimated respectively to compensate the attenuation due to the fading. And in time domain, the frequency channel impulse response is averaged to reduce the attenuation due to the AWGN. By the simulation, the performance of MSE, BER and the complexity of calculation is compared and analysized for each interpolation scheme.

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MF 대역 디지털 라디오 방송 시스템을 위한 채널 추정 기법의 성능 분석 (Performance Analysis of Channel Estimation Schemes for MF Band Digital Radio Broadcasting System)

  • 송정훈;김기남;노재성;조성준
    • 한국전자파학회논문지
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    • 제15권2호
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    • pp.217-222
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    • 2004
  • 본 논문에서는 AM 대역 디지틸 라디오 방송의 표준안인 DRM 시스템에 효율적인 채널 추정 방식에 대해 비교, 분석하였다. 채널의 다중경로 페이딩을 보상하기 위해 주파수 영역에서 선형 보간법, 이차 보간법, cubic-spline 보간법, time-domain 보간법을 통하여 채널을 추정하였다. 그리고 잡음에 의한 왜곡을 제거하기 위해 채널의 주파수 응답을 시간축으로 평균을 취하였다. 각 보간 방식의 성능 분석을 위해 시뮬레이션을 수행하여 MSE, BER의 성능과 연산의 복잡도를 비교, 분석하였다.

A Study on Feasibility of Dual-Channel 3DTV Service via ATSC-M/H

  • Kim, Byung-Yeon;Bang, Min-Suk;Kim, Sung-Hoon;Choi, Jin-Soo;Kim, Jin-Woong;Kang, Dong-Wook;Jung, Kyeong-Hoon
    • ETRI Journal
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    • 제34권1호
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    • pp.17-23
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    • 2012
  • This paper analyzes the feasibility of a new 3DTV broadcasting service scenario via Advanced Television Systems Committee Mobile/Handheld (ATSC-M/H). We suggest a dual-channel system in which a left-view image is encoded by MPEG-2 with HD quality and a small-sized right-view image is encoded by AVC. Also, the left view is transmitted through ATSC main channel and the right view is transmitted through ATSC-M/H channel. Although the transport stream formats of two channels are different from each other, we demonstrate that it is possible for the ATSC 2.0 decoder to synchronize the display of the left and right views when both encoders use a common wall clock and time stamp. We also propose a program specific information descriptor which guarantees full compatibility with the conventional 2D HDTV and emerging mobile TV services. Finally, we provide the results of subjective visual quality assessment of the proposed system in support of its 3DTV service quality.

Seamless Video Switching System for Service Compatible 3DTV Broadcasting

  • Kim, Sangjin;Jeon, Taehyun
    • ETRI Journal
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    • 제38권5호
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    • pp.847-857
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    • 2016
  • Broadcasting services such as multi/single channel HDTV and 3DTV/2DTV use a multi-channel encoder that changes the bitrate and composition of the video service depending on the time. However, this type of multi-channel encoder could cause a longer latency owing to the variable bitrate and relatively bigger size of the buffers, which results in the same delay as in 3DTV even for a conventional DTV service. On the other hand, systems built based on separate encoders, each of which is optimized for the target service, might not have such latency problems. Nevertheless, there might be a distortion problem in the image and sound at the time of a switchover between two encoders with different output bitrates and group of picture structures. This paper proposes a system that can realize a seamless video service conversion using two different video encoders optimized for each video service. An overall functional description of the video service change control server, which is a main control block for the proposed system, is also provided. The experiment results confirm the seamless switchover and reduced broadcasting latency of DTV services compared with a broadcasting system composed of a multi-channel encoder system.

Secure Broadcasting Using Multiple Antennas

  • Ekrem, Ersen;Ulukus, Sennur
    • Journal of Communications and Networks
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    • 제12권5호
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    • pp.411-432
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    • 2010
  • We consider three different secure broadcasting scenarios: i) Broadcast channels with common and confidential messages (BCC), ii) multi-receiver wiretap channels with public and confidential messages, and iii) compound wiretap channels. The BCC is a broadcast channel with two users, where in addition to the common message sent to both users, a private message, which needs to be kept hidden as much as possible from the other user, is sent to each user. In this model, each user treats the other user as an eavesdropper. The multi-receiver wiretap channel is a broadcast channel with two legitimate users and an external eavesdropper, where the transmitter sends a pair of public and confidential messages to each legitimate user. Although there is no secrecy concern about the public messages, the confidential messages need to be kept perfectly secret from the eavesdropper. The compound wiretap channel is a compound broadcast channel with a group of legitimate users and a group of eavesdroppers. In this model, the transmitter sends a common confidential message to the legitimate users, and this confidential message needs to be kept perfectly secret from all eavesdroppers. In this paper, we provide a survey of the existing information-theoretic results for these three forms of secure broadcasting problems, with a closer look at the Gaussian multiple-input multiple-output (MIMO) channel models. We also present the existing results for the more general discrete memoryless channel models, as they are often the first step in obtaining the capacity results for the corresponding Gaussian MIMO channel models.

Implementation of efficient multi-view system through function distribution in digital multi-channel broadcasting service

  • Kwon, Myung-Kyu
    • 한국컴퓨터정보학회논문지
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    • 제22권6호
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    • pp.17-24
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    • 2017
  • In recent digital broadcasting, up to 250 channels are multiplexed and transmitted. The channel transmission is made in the form of MPEG-2 Transport Stream (TS) and transmits one channel (Video, Audio). In order to check if many broadcast channels are transmitted normally, in multi-channel multi-view system, ability of real-time monitoring is required. In order to monitor efficient multi-channel, a distributed system in which functions and load are distributed should be implemented. In the past, we used an inefficient system that gave all of the functionality to a piece of hardware, which limited the channel acceptance and required a lot of resources. In this paper, we implemented a distributed multi-view system which can reduce resources and monitor them economically through efficient function and load balancing. It is able to implement efficient system by taking charge of decoding, resizing and encoding function in specific server and viewer function in separate server. Through this system, the system was stabilized, the investment cost was reduced by 19.7%, and the wall monitor area was reduced by 52.6%. Experimental results show that efficient real-time channel monitoring for multi-channel digital broadcasting is possible.