• Title/Summary/Keyword: Terrestrial System

Search Result 650, Processing Time 0.026 seconds

An effective error resilience coding of MPEG-4 video stream using DMB system (DMB를 통한 MPEG-4 비디오 스트림의 효율적인 오류 내성부호화 방안)

  • 백선혜;나남웅;홍성훈;이봉호;함영권
    • Proceedings of the IEEK Conference
    • /
    • 2003.07e
    • /
    • pp.2060-2063
    • /
    • 2003
  • Terrestrial DMB(Digital Multimedia Broad-casting) system that is now under standardization in Korea offers multimedia broadcasting services at mobile environment and is based on Eureka-147 DAB(Digital Audio Broadcasting) for transmission method. Also DMB provides the error protection method of convolution coding. In this paper, we study on the effective error resilience coding of MPEG-4 video stream over DMB system. In our algorithm, the first, we partition the MPEG-4 data using the MPEG-4 data partitioning method, and then controls the convolution coding rate according to the importance of the partitioned data. From our simulation result, we show that our algorithm is proper for terrestrial DMB services.

  • PDF

Adaptive Power Allocation Scheme for Mobile Satellite Systems Using LTE-Advanced (LTE-Advanced 기반 이동 위성 시스템을 위한 적응형 전력 할당 방식)

  • Yeo, Sung-Moon;Kang, Kun-Seok;Kim, Soo-Young;Ku, Bon-Jun
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.49 no.6
    • /
    • pp.1-7
    • /
    • 2012
  • Due to the increasing demand of network convergence, in future, hybrid/integrated satellite and terrestrial systems will play an important role. In that case, compatibilities between the satellite and terrestrial systems are very important for efficiency of the systems. 3GPP Long Term Evolution (LTE) is one of the 4G system. Therefore, in this paper, we introduce the design of interleaver for mobile satellite system based 3GPP LTE specification. The 4G system including the LTE specification adopted adaptive modulation and coding (AMC) schemes for efficient usage of resources, and the updating interval of resource allocation is an order of msec. However, because of the long round trip delay of satellite systems, we cannot employ the same AMC scheme specified for the terrestrial system, and thus it cannot effectively counteract to short term fadings. Therefore, in order to overcome these problems, we propose an interleaver scheme combined with AMC. We present the interleaver design results considering mobile satellite system based on the LTE and analyze the simulation results.

Modeling & Simulation Software Design for Coverage Analysis of Multiple Radio Positioning Integration System

  • Koo, Moonsuk;Kim, YoungJoon;So, Hyoungmin;Oh, Sang Heon;Kim, Seong-Cheol;Hwang, Dong-Hwan
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.5 no.2
    • /
    • pp.47-57
    • /
    • 2016
  • Since the Global Navigation Satellite System (GNSS) may not provide navigation information due to external interferences, many countries have plans to prepare a backup system for this situation. One of the possible GNSS backup systems is a multiple radio positioning integration system in combination with the terrestrial radio navigation system. Before constructing such a GNSS backup system, M&S software is needed to analyze if the system satisfies the performance the required navigation performance. This study presents requirements of M&S software for coverage analysis of the navigation system, and proposes an M&S software design scheme on the basis of the requirements. The M&S software is implemented, and coverage analysis is performed to verify the validity of the proposed design scheme.

Building IEC 61850 SCADA system based on TETRA (TETRA 기반 IEC 61850 SCADA 시스템 구축)

  • Song, Byung-Kwen;Jeong, Tae-Ui
    • Journal of IKEEE
    • /
    • v.13 no.3
    • /
    • pp.87-94
    • /
    • 2009
  • TETRA(TErrestrial Trunked RAdio) is the wireless communication system generally adopted to public network and backbone network, as the technology of Trunked Radio System specified by ETSI(European Telecommunications Standards Institute) and currently adopted to the Electric Power IT Backbone Network in Korea. IEC 61850 is the protocol proposed for SAS(Substation Automation System) of SCADA(Supervisory Control And Data Acquisition) system. In this paper, IEC 61850 Server and Client simulator are used based on Linux operating system. The multi-functional gateway, which transforms the communication based on TCP/IP between IEC 61850 Server Simulator and Client Simulator to the one based on TETRA Packet Data Service, is developed such that IEC 61850 SCADA system is constructed based on TETRA.

  • PDF

Measurement of Joint-Orientation and Monitoring of Displacement in Tunnel using 3D Laser Scanning System (3차원 레이저 스캐닝 시스템을 이용한 불연속면의 방향성 측정과 터널 변위 모니터링)

  • Shon, Ho-Woong;Oh, Seok-Hoon;Kim, Young-Kyung
    • Journal of the Korean Geophysical Society
    • /
    • v.9 no.1
    • /
    • pp.47-62
    • /
    • 2006
  • More than 70% of Korean Peninsula is consisted of mountains, so that lots of roads, rail-roads and tunnel,which play a pivotal role in the industry activity, are existed along the rock-slope and in the rock-mass. Thus,it is urgent that tegration of management system through the optimum survey and design of rock-slope excavation, proper stabilization method and database of rock-slope. However, conventional methods have shortcoming with the economy of survey time and human resources, and the overcome of difficulties of approach to the in-situ rock-slope. To overcome the limitation of conventional method, this paper proposed the development of remote measurement system using Terrestrial Laser Scanning System. The method using Terrestrial 3D Laser Scanning System, which can get 3D spatial information on the rock-slope and2)Dept. Geosystem Engineering, Kangwon National University, Korea tunnel, has an advantage of reduction of measurement time and the overcome of difficulties of approach to the in-situ rock-slope/dam/tunnel. In the case of rock-slope, through the analysis of 3D modeling of point-cloud by Terrestrial Laser Scanning System, orientation of discontinuity, roughness of joint surface, failure shape and volume were successively achieved. in the case of tunnel face, through reverse-engineering, monitoring of displacement was possible.

  • PDF

Improving the Ownership Regulation in the Broadcasting Industry (방송사업의 소유겸영규제 개선)

  • LEE, Suil
    • KDI Journal of Economic Policy
    • /
    • v.33 no.4
    • /
    • pp.85-118
    • /
    • 2011
  • This paper uses the horizontal regulation system as the base analysis framework. The study clearly defines the regulatory goals of the followings: the horizontal cross-ownership regulations on program provider (PP) and platform provider, the vertical regulation on cross-ownership between PP and platform operator, the regulation on cross-ownership of program provider by terrestrial broadcasting company, and the regulation on cross-ownership between terrestrial broadcasting company and platform provider. Then, by analyzing the conformity between goals and criteria of regulations and the adequacy of the regulation level according to regulatory purposes, this paper examines the justifiability of each regulation and extracts improvement measures that suite regulatory purposes. This analysis finds following appropriate measures: replacing the horizontal cross-ownership regulation on PP with conduct regulations, such as designating major broadcasting programs or replacing the current criterion of cross-ownership regulation from sales to the audience market share; reshaping the horizontal cross-ownership regulation on platform provider so that system operator (SO), satellite broadcaster and Internet protocol television (IPTV) operator would be applied by the same regulation based on the number of subscribers of pay television services; and discontinuing other cross-ownership regulation. In this way, the study shows that with appropriate regulations on cross-ownership of PP, there would be no need for additional regulation on vertical integration between PP and platform operator. On the other hand, given that the regulation on terrestrial broadcasting cross-ownership of PP could be justified only by regulatory purpose of the protection of the diversity of public opinions, it would be desirable to replace the current criteria of the number of PPs with the criteria of the audience market share. Lastly, the study shows that when platform operator is targeted by the cross-ownership regulation based on the number of subscribers of pay television services, the regulation on cross-ownership between terrestrial broadcasting company and platform provider should be replaced with conduct regulations, such as designating must-offer channels and major broadcasting programs.

  • PDF

Enhanced-xVSB System Development for Next Generation Terrestrial DTV RF Transmission (차세대 지상파 DTV 전송시스템 개발)

  • Kim, Sung-Hoon;Lee, Jae-Youn;Lee, Soo-In;Ahn, Chie-Teuk;Kim, Ki-Doo
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2006.11a
    • /
    • pp.187-190
    • /
    • 2006
  • In this paper, we describe a new 1/4 rate robust modulation techniques for Enhanced-x VSB system which is fully backward compatible with ATSC 8-VSB standard. 1/4 rate mode Enhanced-xVSB system provides broadcasters with a wide choice of trade-offs of data rate vs amount of robustness of enhanced data for pedestrian/mobile services. Lab test results of proposed Enhanced-xVSB 1/4 rate mode robust stream are a significantly improved multipath as well as AWGN reception performance for Enhanced-xVSB receiver. We suggest an Enhanced-xVSB terrestrial broadcasting system for ATSC HDTV and pedestrian/portable TV simultaneous broadcasting service providing.

  • PDF

Calibration of Hydrographic Survey Multibeam System Using Terrestrial Laser Scanning and TS Surveying (지상 레이저 스캐닝과 TS 측량을 이용한 멀티빔 시스템의 검·보정)

  • Kim, Jin Soo
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.31 no.3
    • /
    • pp.199-207
    • /
    • 2013
  • In hydrographic survey, data surveyed with multibeam system includes various errors due to multiple factors. These are corrected by a calibration called patch test, and if existing method is used, the test needs to be conducted for about 8 times for precise system calibration. For more prompt and precise multibeam system calibration, the exact offset of a ship was determined using terrestrial laser scanning and TS surveying, which was used as the initial input for the patch test. In the result, the error of closure was 0.001 m or less for TS surveying and backsight error was 0.005 m or less for scanning. All the surveying data based on the same local coordinate was converted into vessel reference coordinate during which R-square for all rotation angles was 0.99 or higher and standard deviation was 0.008 m or less. Finally, in a patch test using calculated offset of sensors and motion sensor offset, the offset of MBES transducer satisfied manual on hydrography only with 1-time calibration. With these results, it is thought that terrestrial laser scanning and TS surveying can fully be utilized for multibeam system calibration.

Interference-aware Resource Allocation Scheme for VHF Data Exchange-terrestrial in Maritime Communication (해상 통신에서 지상파 VHF 데이터 교환을 위한 간섭 인지 기반 자원 할당 기법)

  • Sol-Bee Lee;Jung-Hyok Kwon;Hwa-Jin Na;Kyung-Tae Kim;Hyung-Jin Moon;Bu-Young Kim;Woo-Seong Shim;Dongwan Kim;Eui-Jik Kim
    • Journal of Internet of Things and Convergence
    • /
    • v.10 no.4
    • /
    • pp.109-115
    • /
    • 2024
  • This paper proposes an interference recognition-based resource allocation (IaRA) scheme for very high frequency (VHF) data exchange-terrestrial (VDE-TER) to ensure the reliability of automatic identification system (AIS) message transmission in a coastal environment with dense vessels. To this end, IaRA conducts channel selection and slot allocation based on scheduling information obtained through monitoring VHF data exchange system (VDES) channels. The simulation results show that IaRA achieved an 8.79% higher packet delivery ratio (PDR) and a 9.69% lower channel interference ratio (CIR) compared to the VDE-TER resource allocation scheme of the existing VDES standard.

Design and Implementation of Clipcast Service via Terrestrial DMB (지상파 DMB를 이용한 클립캐스트 서비스 설계 및 구현)

  • Cho, Suk-Hyun;Seo, Jong-Soo
    • Journal of Broadcast Engineering
    • /
    • v.16 no.1
    • /
    • pp.23-32
    • /
    • 2011
  • Design and Implementation of Clipcast Service via Terrestrial DMB This paper outlines the system design and the implementation process of clipcast service that can send clips of video, mp3, text, images, etc. to terrestrial DMB terminals. To provide clipcast service in terrestrial DMB, a separate data channel needs to be allocated and this requires changes in the existing bandwidth allocation. Clipcast contents can be sent after midnight at around 3 to 4 AM, when terrestrial DMB viewship is low. If the video service bit rate is lowered to 352 Kbps and the TPEG service band is fully used, then 320 Kbps bit rate can be allocated to clipcast. To enable clipcast service, the terminals' DMB program must be executed, and this can be done through SMS and EPG. Clipcast service applies MOT protocol to transmit multimedia objects, and transmits twice in carousel format for stable transmission of files. Therefore, 72Mbyte data can be transmitted in one hour, which corresponds to about 20 minutes of full motion video service at 500Kbps data rate. When running the clip transmitted through terrestrial DMB data channel, information regarding the length of each clip is received through communication with the CMS(Content Management Server), then error-free files are displayed. The clips can be provided to the users as preview contents of the complete VOD contents. In order to use the complete content, the user needs to access the URL allocated for that specific content and download the content by completing a billing process. This paper suggests the design and implementation of terrestrial DMB system to provide clipcast service, which enables file download services as provided in MediaFLO, DVB-H, and the other mobile broadcasting systems. Unlike the other mobile broadcasting systems, the proposed system applies more reliable SMS method to activate the DMB terminals for highly stable clipcast service. This allows hybrid, i.e, both SMS and EPG activations of terminals for clipcast services.