• Title/Summary/Keyword: HFC-CATV

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HFC CATV 망의 전송 및 데이터 통신

  • 황승오;박종헌;박승권
    • Information and Communications Magazine
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    • v.15 no.7
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    • pp.75-94
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    • 1998
  • In this paper, HFC CATV networks are introduced. HFC CATV networks are currently considered as a most effective and plausible solution for subscriber access networks in the information superhighway, among others such as ADSL and B-WLL. The advantages of HFC CATV networks include its broad upstream and downstream channel bandwidths, much wider than PSTN's and its readiness. The HFC CATV networks are already well spread among the general subscribers in Korea. This fact will shorten the installation period and significantly reduce its cost. In addition, The structure and channel environment of the HFC CATV networks are introduced. At the same time, in this paper included are major problems in the HFC CATV networks and the solutions for these problems. Also discussed are data transmission, medium access control, IEEE802.14, and MCNS for standardizations. Moreover, additional telecommunications service activities in both Korea and other countries, using HFC CATV networks are also included. The topics which are covered in detail are the ones such as interoperation between HFC CATV networks and trunk line and the digital transmission performance test for the CATV networks. In the performance test, it is concluded that HFC CATV networks can satisfy the QoS for various additional services if the number of the subscribers in a cell is limited to less than 500 and other minor requirements are satisfied. Based on all these discussions and conclusions, HFC CATV networks are suggested in this paper for the subscriber access networks of the so called information superhighway.

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Performance Analysis of an Collision Resolution Algorithm in HFC-CATV Network (HFC-CATV 망에서의 충돌해결알고리즘에 대한 성능분석)

  • 이수연;안정희
    • The Journal of the Korea Contents Association
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    • v.2 no.3
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    • pp.113-118
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    • 2002
  • To provide interactive sonics in HFC(Hybrid Fiber Coax)-CATV network, there must be supported a MAC(Medium Access Control) protocol. It is wet known that collision can be occurred in the HFC upstream channel because it is shared by up to 500 users. Thus it needs the collision resolution algorithm. Consequently, this paper proposes the analysis mood to study stability of binary stack algorithm for adaptive collision resolution algorithm in HFC-CATV. Also, it compares a system throughput between IPP model and D-BMAP model.

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A MAC Protocol for Supporting QoS of Multimedia over HFC-CATV Network (HFC-CATV 망에서 멀티미디어 QoS 제공을 위한 MAC 프로토콜)

  • 이수연;안정희
    • Proceedings of the Korea Multimedia Society Conference
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    • 2002.11b
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    • pp.553-556
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    • 2002
  • 최근 초고속 통신망의 하부 가입자망으로 HFC-CATV에 관한 연구가 활발하게 이루어지고 있다. 특히, HFC-CATV 망은 양방향 멀티미디어 서비스를 제공할 수 있는 것이 특징이다. 따라서 본 논문에서는 HFC-CATV 망을 이용하여 다양한 멀티미디어 트래픽의 QoS를 만족시키기 위한 매체접근제어 프로토콜 중 우선순위 큐(Priority Queue)와 마이크로슬롯을 이용한 MAC 프로토콜을 제안한다. 제안한 알고리즘의 우수성을 입증하기 위해 기존 표준안에서 제안한 알고리즘과 비교 시뮬레이션을 통해 성능분석을 하였다.

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The Analysis of the Subscriber Capacity in a Cell of Data Service HFC Network (데이터 서비스용 HFC망에서 셀당 가입자 수용능력 분석)

  • 장태우
    • Proceedings of the IEEK Conference
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    • 2001.06a
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    • pp.371-374
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    • 2001
  • The upstream noise level was measured and analysed for the sample HFC networks to HFC subscriber capacity in the HFC network that is only for cable modem services. The upstream bands were measured not only in HFC networks that have accommodated only cable modem subscribers but in CATV networks that have accommodated cable modem and CATV subscribers. The study says that C/N of HFC networks be maintained though the networks have more cable modem subscribers than CATV networks do. This results are being expected to be used as a basis of network design and management of HFC network provider .

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A Performance Analysis of DPA(Dynamic Priority Assignment) MAC Protocol for traffic QoS Improvement on HFC-CATV Network (HFC-CATV 망에서 트래픽 QoS 향상을 위한 DAP MAC 프로토콜 성능분석)

  • Lee, Su-Youn
    • Convergence Security Journal
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    • v.11 no.1
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    • pp.3-10
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    • 2011
  • This paper proposes DPA(Dynamic Priority Assignment) MAC protocol to improve the traffic QoS on the HFC-CATV(Hybrid Fiber Coax CAble TeleVision) network. In results, DPA MAC protocol is the best performance compare with to IEEE 802.14a MAC in mean request delay, mean access delay. Also, the paper prove a reliability of proposed protocol through comparison between performance analysis and simulation result of DAP MAC protocol.

Study of Modeling HFC Networks Upstream Channel and Performance Improvement of Two-Way CATV System (HFC망 상향채널 모델링과 양방향 CATV 시스템의 성능 개선에 대한 연구)

  • 이재일;서종수
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2000.11b
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    • pp.3-8
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    • 2000
  • 본 논문에서는 고품질의 DTV, HDTV와 인터넷 등의 고속 광대역 멀티미디어 서비스를 위한 HFC(Hybrid Fiber Coaxial)-CATV망의 상향채널을 SPW(Signal Processing Worksystem)를 사용하여 모델링하고, HFC-CATV망 상향채널의 문제점인 유입잡음의 영향을 전산모의 실험을 통해 분석하였다. 그리고 상향채널의 열악성을 극복할 수 있는 방법으로 트렐리스 부호화 변조(Trellis-Coded Modulation)와 OFDM(Orthogonal Frequency Division Multiplexing)을 결합한 OFDM-TC8PSK 시스템을 제안하고 그 성능을 CATV 상향채널 환경에서 전산모의 실험하고 기존의 QPSK 시스템의 성능과 비교 분석하였다.

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Study on Dynamic Priority Collision Resolution Algorithm in HFC-CATV Network (HFC-CATV 망에서 동적 우선순위 충돌해결알고리즘에 관한 연구)

  • Lee, Su-Youn;Chung, Jin-Wook
    • The KIPS Transactions:PartC
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    • v.10C no.5
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    • pp.611-616
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    • 2003
  • Recently, the HFC-CATV network stand in a substructure of superhighway information network. Because of sharing up to 500 of subscribes, the Collision Resolution Algorithm needs in the upstream channel of HFC-CATV network. In order to provide Quality of Service (QoS) to users with real-time data such as voice, video and interactive service, the research of Collision Resolution Algorithm must include an effective priority scheme. In IEEE 802.14, the Collision Resolution Algorithm has high request delay because of static PNA(Priority New Access) slots structure and different priority traffics with the same probability. In order to resolve this problem, this paper proposed dynamic priority collision resolution algorithm with ternary tree algorithm. It has low request delay according to an increase of traffic load because high priority traffic first resolve and new traffic content with different probability. In the result of the simulation, it demonstrated that the proposed algorithm needs lower request delay than that of ternary tree algorithm with static PNA slots structure.

Implementation on On-Demand System using ATM/HFC Network (ATM/HFC망을 이용한 On-Demand 시스템 구현)

  • 김광수
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1999.06b
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    • pp.149-155
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    • 1999
  • 방송과 통신산업의 융합현상이 가속화됨에 따라, CATV망을 이용하여 다양한 영상, 음성, 데이터 통신을 위한 새로운 기술과 서비스의 요구가 증가하고 있다. 디지털 방식의 CATV를 위한 세계적 표준화 작업이 선진국을 중심으로 진행되고 있으며, 국내에서도 이에 따른 기술개발의 목표 및 규격설정을 통한 호환성 보장 체계가 필요함에 이를 위한 연구개발을 수행하였다. CATV의 디지털화는 MoD, 화상전화, 고속 인터넷 와 같은 다양한 디지털 서비스를 CATV사업자가 가입자에게 제공함으로써 서비스 폭을 넓히는 FSN(Full Service Network)의 기반으로 활용할 수 있다.

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Study on Medium Access Control Protocol with a Priority Scheme for HFC-CATV Network (HFC-CATV 망에서 우선순위를 제공하는 MAC 프로토콜 연구)

  • Lee, Su-Youn;Chung, Jin-Wook
    • Proceedings of the Korea Information Processing Society Conference
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    • 2003.05b
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    • pp.1253-1256
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    • 2003
  • HFC(Hybrid Fiber Coax)망은 광케이블 구간과 동축케이블 구간으로 나뉘어져 있으며 광케이블 구간은 성형(Star)구조를 가지며 동축케이블 전송구간은 수지분기형(Tree and Branch)구조로 되어있다. HFC망의 상향채널은 가입자에서 헤드앤드로 데이터 전송 시 500가입자 이상이 공유하기 때문에 이를 제어하기 위한 매체접근제어(Medium Access Control)프로토콜이 필요하다. 특히, 음성, 비디오 그리고 데이터와 같은 트래픽의 QoS(Quality of Service)를 만족시키기 위해서는 서비스별로 우선 순위를 고려한 충돌해결알고리즘이 요구되어진다. 그러므로, 본 논문에서는 기존 알고리즘의 문제점을 분석하여 트래픽 특성에 따라 우선순위를 제공하는 충돌해결알고리즘을 제안하였다.

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A Study on the Convergence of CATV Networks for Ultra High Speed Internet Service (초고속 인터넷 서비스를 위한 CATV 망의 융복합 연구)

  • Park, Yong-Seo
    • Journal of Digital Convergence
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    • v.13 no.9
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    • pp.219-224
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    • 2015
  • The broadcasting communications service will accelerate its development with the convergence of broadcasting media and internet service. In the field of CATV network related technology, only those service providers will be able to survive in future, and they can combine available services in the most effective and economical way. This research aims to explain the CATV status of Korea and China and its technology trends. It also analyzes CMC(Cable Modem Concentrator) technology, suggested as one of the high-speed internet technology. CMC technology has the advantages of enhancing the transmission speed while using the existing basic structure of HFC network and expanding service area by adding amplifiers within CMC. The distance between coaxial cables is getting shorter with more concentrated areas in large cities in Korea. However, in China, the demand for long distance transmission service is increasing. CMC technology satisfies both short and long distance service subscribers without any geographical limitations. With these advantages, CMC technology is expected to generate lots of economic benefits if applied for the CATV network in the area of China, Middle East, and Southeast Asia.