• Title/Summary/Keyword: Terrestrial broadcasting

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Study on the technology of ATSC terrestrial DTV broadcasting service using single frequency networks (단일 주파수 망을 이용한 ATSC 지상파 디지털 TV 방송서비스 기술 연구)

  • 박성익;이용태;김승원;이수인
    • Journal of Broadcast Engineering
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    • v.8 no.2
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    • pp.109-115
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    • 2003
  • In this paper we propose an efficient method to broadcast digital television signals using Single Frequency Networks (SFNs) in the Advanced Television Systems Committee (ATSC) transmission systems. Since the proposed schemes to synchronize multiple transmitters minimize the changes from the conventional ATSC system, the hardware complexity for the changes is very low. Our simulation results show that the proposed scheme makes less than 0.1 dB degradation at the threshold of visibility (TOV: BER= 3$\times$$10^{-6}$) in the additive white Gaussian noise (AWGN) channel. It is possible to reduce the performance degradation by increasing an initialization period of the proposed scheme.

Mobile Performance Evaluation of ISDB-T Full-Segment TV Receiver (ISDB-T 풀세그 TV 수신기 이동 성능 평가)

  • Gu, Young Mo
    • Journal of Broadcast Engineering
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    • v.23 no.2
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    • pp.293-301
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    • 2018
  • In ISDB-T, which is Japanese digital terrestrial TV specification based on OFDM technology, 6MHz bandwidth is divided into 13 segments. Twelve segments (full-seg) are used for high definition broadcasting for fixed receivers and one segment (one-seg) for mobile receivers. Though one-seg supports high speed mobility by using QPSK modulation, it is not suitable for large display mobile devices because of its low data rate. Full-seg using 64QAM modulation also suffers from its low mobile performance. In this paper, mobile performance of ISDB-T full-seg receiver is evaluated by applying sub-carrier interference removing scheme, high speed mobile channel estimation scheme and antenna diversity scheme.

Analysis and Simulation of D-TV System (D-TV 시스템의 성능해석 및 시뮬레이션)

  • Youn Hyeok-Joon;Ha Yeon-Chul;Ko Bong-Jin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.623-627
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    • 2006
  • In this paper, we simulated terrestrial digital broadcasting system and analyzed the performance of 8-VSB signal and carried out baseband simulation of tranceiver modeling by standard parameter and passband simulation for interchannel interference. Also, an error rate equation for fading and interference of 8-VSB signal is derived. As a result, the case not to consider Rician fading, the influence of the interference did not exist if frequency interval fell of over the 20MHz. The case to consider Rician fading, the system had the degradation of the performance.

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A New Upper Layer Decoding Algorithm for MPE-FEC based on LLR (LLR 기반의 MPE-FEC 상위계층 복호 방식)

  • Kim, Chul-Seung;Kim, Min-Hyuk;Park, Tae-Doo;Kim, Nam-Soo;Jung, Ji-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.10
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    • pp.2227-2234
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    • 2009
  • DVB-SSP is a new broadcasting system for hybrid satellite communications, which supports mobile handheld systems and fixed terrestrial systems. An upper layer, including erasure Reed-Solomon error correction combined with cyclic redundancy check. However, a critical factor must be considered in upper layer decoding. If there is only one bit error in an IP packet, the entire IP packet is considered as unreliable bytes, even if it contains correct bytes. If, for example, there is one real byte error, in an IP packet of 512 bytes, 511 correct bytes are erased from the frame. Therefore, this paper proposed upper layer decoding methods; LLR-based decoding. By means of simulation we show that the performance of the proposed decoding algorithm is superior to that of the conventional one.

The Potential of IPTV Service: Is It a Bridging or Gap-filling Telecommunication Service? (기존 신규 방송통신서비스 분석을 통한 IPTV 서비스의 성장가능성 연구)

  • Lee, Hyeongjik;Kim, Kyoungtae;Jeong, Bo Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.05a
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    • pp.525-528
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    • 2009
  • This paper attempts to conceptually examine the potential of IPTV(Internet Protocol Television). First, this paper reviews the concept of a bridging telecommunication service and a gap-filling telecommunications service. Second, the current status of various emerging telecommunications services including mobile WiMax, called WiBro, and both satellite and terrestrial digital multimedia broadcasting service, called DMB are comprehensively analyzed. Based on those analysis, this paper analyzes whether IPTV is regared as a bridging telecommunications service or a gap-filling telecommunications service and examine the potential growth possibility of IPTV. Finally, the suggestions for policy makers are discussed.

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Research on Archive Opening and Sharing Projects of Korean Terrestrial Broadcasters and External Users of Shared Archives : Focusing on the Case of the 5.18 Footage Video Sharing Project 〈May Story(Owol-Iyagi)〉 Contest Organized by KBS (국내 지상파 방송사의 아카이브 개방·공유 사업과 아카이브 이용자 연구 KBS 5.18 아카이브 시민공유 프로젝트 <5월이야기> 공모전 사례를 중심으로)

  • Choi, Hyojin
    • The Korean Journal of Archival Studies
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    • no.78
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    • pp.197-249
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    • 2023
  • This paper focus on the demand for broadcast and video archive contents by users outside broadcasters as the archive openness and sharing projects of terrestrial broadcasters have become more active in recent years. In the process of creating works using broadcasters' released video footage, the study examined the criteria by which video footage is selected and the methods and processes utilized for editing. To this end, the study analyzed the the case of the 5.18 footage video sharing project 〈May Story(Owol-Iyagi)〉 contest organized by KBS in 2022, in which KBS released its footage about the May 18 Democratic Uprising and invited external users to create new content using them. Analyzing the works that were selected as the winners of the contest, the research conducts in-depth interviews with the creators of each work. As a result, the following points are identified. Among the submitted works, many works deal with the direct or indirect experience of the May 18 Democratic Uprising and focus on the impact of this historical event on individuals and our current society. The study also examined the ways in which broadcasters' footage is used in secondary works. We found ways to use video as a means to share historical events, or to present video as evidence or metaphor. It is found that the need for broadcasters to provide a wider range of public video materials such as the May 18 Democratic Uprising, describing more metadata including copyright information before releasing selected footage, ensuring high-definition and high-fidelity videos that can be used for editing, and strengthening streaming or downloading functions for user friendliness. Through this, the study explores the future direction of broadcasters' video data openness and sharing business, and confirms that broadcasters' archival projects can be an alternative to fulfill public responsibilities such as strengthening social integration between regions, generations, and classes through moving images.

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Joint Quality Control of MPEG-2 Video Programs for Digital Broadcasting Services (디지털 방송 서비스를 위한 MPEG-2 비디오 프로그램들의 결합 화질 제어)

  • 홍성훈;김성대
    • Journal of Broadcast Engineering
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    • v.3 no.1
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    • pp.69-84
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    • 1998
  • In digital broadcasting, services such as digital satellite TV, cable TV and digital terrestrial TV, several video programs are compressed by MPEG-2, and then simultaneously transmitted over a conventional CBR (Constant Bit Rate) broadcasting channel. In this paper, we propose a joint quality control scheme to be able to accurately control the relative picture quality among the video programs, which is achieved by simdt;,nL'Ously controlling the video encoders to generate the VBR (Variable Bit Rate) compressed video streams. Our quality control scheme can prevent the video buffer overflow and underflow by total target bit allocation process, and also exactly control the relative picture quality in terms of PSNR (Peak Signal to Noise Ratio) between some programs requiring higher picture quality and others by rate-distortion modification. Furthermore we present a rate-distortion estimation method for MPEG-2 video, which is base of our joint quality control, and verify its performance by experiments. The most attractive features of this estimation method are as follows: 1) computational complexity is low because main operation for the estimation is to calculate the histogram of OCT coefficients into quantizer; 2) estimation results are very accurate enough to be applied to the practical MPEG-2 video coding applications. Simulation results show that the proposed joint quality control scheme accurately controls the relative picture quality among the video progran1s transmitted over a single channel as well as provides more consistent and higher picture quality than independent coding scheme that encodes each program independently.

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A New Upper Layer Decoding Algorithm for a Hybrid Satellite and Terrestrial Delivery System (혼합된 위성 및 지상 전송 시스템에서 새로운 상위 계층 복호 알고리즘)

  • Kim, Min-Hyuk;Park, Tae-Doo;Kim, Nam-Soo;Kim, Chul-Seung;Jung, Ji-Won;Chun, Seung-Young
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.9
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    • pp.835-842
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    • 2009
  • DVB-SSP is a new broadcasting system for hybrid satellite communications, which supports mobile handheld systems and fixed terrestrial systems. However, a critical factor must be considered in upper layer decoding which including erasure Reed-Solomon error correction combined with cyclic redundancy check. If there is only one bit error in an IP packet, the entire IP packet is considered as unreliable bytes, even if it contains correct bytes. IF, for example, there is one real byte error, in an If packet of 512 bytes, 511 correct bytes are erased from the frame. Therefore, this paper proposed two kinds of upper layer decoding methods; LLR-based decoding and hybrid decoding. By means of simulation we show that the performance of the proposed decoding algorithm is superior to that of the conventional one.

A Study on the Decline of 'Orientating Journalism' in Korean News Media: An Empirical Analysis of News Coverage of Major Newspapers and Terrestrial TV (매체 간 경쟁의 심화에 따른 안내적 저널리즘의 약화: 중앙종합언론의 보도에 대한 실증적 분석)

  • Jang, Ha-Yong
    • Korean journal of communication and information
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    • v.56
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    • pp.48-70
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    • 2011
  • Although many researchers propose that market-driven journalism is incurred by the worsening of financial situation as a result of intensifying competition in mass media industry, few studies investigated this claim with actual news data. This study analyzed the headline news of eight major newspapers and two terrestrial TV companies to find the weakening of 'orientating-journalism' function of Korean news media. The results revealed that the duplication rate of news items among ten news companies were decreasing, and the range of news subjects were broadened into diverse topics during last ten years. Therefore it seemed that the tendency of monopolization of a certain events or issues was weakening in news reporting. The financial situation of news companies is an important factor in explaining the change of news reporting. The companies with more worse financial situation have higher duplication rate of news topics along as the more amount of soft news items, leading to the gradual deterioration of their own voices in reporting. The rate of 'independent issue report' was also less than seven precent, thus their reporting is evaluated as having many limitations. In sum, the major newspapers and network broadcasting companies are still exerting strong influences in agenda-setting, but they(mostly newspapers) are suffering from the financial problems, resulting the deterioration of performing orientation journalism function. This study concluded with remarks about the role of major news media in current changing situation.

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Target Advertisement based on a TV Viewer's Profile Inference and TV Anytime Metadata (시청자 프로파일 추론과 TV Anytime 메타데이타를 이용한 표적 광고)

  • Kim, Mun-Jo;Lee, Bum-Sik;Lim, Jeong-Yon;Kim, Mun-Churl;Lee, Hee-Kyung;Lee, Han-Gyu
    • Journal of KIISE:Computer Systems and Theory
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    • v.33 no.10
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    • pp.709-721
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    • 2006
  • The traditional broadcasting services over terrestrial, satellite and cable media have been unidirectional mass media regardless of TV viewer's preferences. Recently ich media streaming has become possible via the broadb and networks. Furthermore, since bidirectional communication is possible, personalcasting such as personalized streaming services has been emerging by taking into account the user's preference on content genres, viewing times and actors/actresses etc. Accordingly, personal media becomes an important means for content provision service in addition to the traditional broadcasting service as mass media. In this paper, we introduce a user profile reasoning method for target advertisement which is considered an important application in personalcasting service. The proposed user profile reasoning method predicts an unknown TV viewer's gender and ages by analyzing TV Viewing history data. Based on the estimated user's gender and ages, a target advertisement is provided with TV Anytime metadata. A proposed target advertisement system is developed based on the user profile reasoning and the target advertisement selection method. To show the effectiveness of our proposed methods, we present a plenty of experimental results by using realistic TV viewing history data.