• Title/Summary/Keyword: satellite broadcast

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디지털 방송 수신기 기술

  • 장현식;김용석;정주홍
    • The Magazine of the IEIE
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    • v.29 no.7
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    • pp.51-58
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    • 2002
  • This paper describes functions required for implementation of digital television (DTV) broadcast receivers. The necessary functions for the DTV receiver vary with the transmission media-terrdstrial, cable and satellite. This paper briefly introduces its hardware and software structure, This paper also presents the future of DTV receivers according to the tomorrow's broadcast environment.

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Digital Broadcasting industry: Today & Tomorrow

  • Kim, Kook-Jin
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2002.05a
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    • pp.3-16
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    • 2002
  • .Service Industry good digital contents are few high cost of broadcasting right Satellite broadcasting will be dominant in many countries Interactive TV service will be an engine of digital broadcasting .DTVsets Industry Big Market is coming

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Performance Analysis of the Encryption Algorithms in a Satellite Communication Network based on H-ARQ (H-ARQ 기반 위성통신망에서 암호화 알고리즘에 따른 성능 분석)

  • Jeong, Won Ho;Yeo, Bong-Gu;Kim, Ki-Hong;Park, Sang-Hyun;Yang, Sang-Woon;Lim, Jeong-Seok;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.45-52
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    • 2015
  • Since the broadcast message in satellite signals the security of the data is extremely poor compared to other communication technologies such as the broadcast signal. Thus, encryption of the communication satellite has become a very important issue, an analysis of the communication performance of a general service is always required. In this paper, In order to analyze the encrypted communication the turbo code in an IP-based satellite communication applies the code rate compatible punctured and The wireless channel in consideration of the actual satellite communication was constructed by placing a weight on the Rayleigh fading and the Rician fading two channels. Retransmission-based error control scheme were constructed in the best performance of H-ARQ Type-II, III scheme of a number of ways that are recently considered. we analyzed the effects of normal service against a satellite communication network The security services were configured with encryption algorithms AES, ARIA (CTR, CBC mode).

Scene Change Detection In the Hard Disk Drive Embedded Digital Satellite Receiver for Video Indexing (하드디스크를 내장한 디지털 위성방송수신기에서 비디오 인덱스를 위한 장면 전환 검출)

  • 성영경;최윤희;최태선
    • Proceedings of the IEEK Conference
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    • 2002.06d
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    • pp.259-262
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    • 2002
  • In this paper, we present a hard disk drive embedded digital satellite receiver with scene change detection for video indexing. This receiver can store, retrieve and classify the broadcast data by implementing an interface between the conventional digital satellite receiver and digital storage media. Using this system, user can obtain more information for efficient video retrieval.

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An Analysis on the Long-Term Variation of the GPS Broadcast Ephemeris Errors (GPS 방송궤도력 오차의 장기간 변화 분석)

  • Kim, Mingyu;Kim, Jeongrae
    • Journal of Advanced Navigation Technology
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    • v.18 no.5
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    • pp.421-428
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    • 2014
  • GPS satellite positions can be obtained from the navigation message transmitted from the GPS satellite. In this paper, the accuracy of broadcast orbit and clock are analyzed by comparing with the NGA precise ephemeris. For analyzing global and local orbit errors in 2004 to 2013, GPS satellite visibilities are calculated in Korea. Local RMS of 3D orbit error and SISRE are 4 cm and 3 cm less than global RMS of 3D orbit errors and SISRE. Orbit and clock errors are calculated for each GPS satellite Block for 10 years. SISRE of Block IIA satellites are 2.8 times greater than Block IIF satellites. The correlation between orbit errors and shadow condition is analyzed. The orbit errors in shadow is 2.1% higher than that in sunlight. Correlation analysis between the orbit errors and solar/geomagnetic index shows that orbit errors has a high correlation with from 2004 to 2008. However, the correlation became low since 2009.

Attribute-based Broadcast Encryption Algorithm applicable to Satellite Broadcasting (위성방송에 적용 가능한 속성기반 암호전송 알고리즘)

  • Lee, Moon-Shik;Kim, Deuk-Su;Kang, Sun-Bu
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.2
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    • pp.9-17
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    • 2019
  • In this paper, we propose an attribute-based broadcast encryption algorithm that can be applied to satellite broadcasting network. The encryption algorithm is a cryptographic method by which a carrier(sender) can transmit contents efficiently and securely to a plurality of legitimate users through satellites. An attribute-based encryption algorithm encrypts contents according to property of contents or a user, In this paper, we combine effectively two algorithms to improve the safety and operability of satellite broadcasting network. That is, it can efficiently transmit ciphertexts to a large number of users, and has an advantage in that decoding can be controlled by combining various attributes. The proposed algorithm reduces the network load by greatly reducing the size of the public key, the private key and the cipher text in terms of efficiency, and the decryption operation amount is reduced by half to enable fast decryption, thereby enhancing the operability of the user.

A Study of Public Test-bed Operation for Satellite Communications via COMS (천리안 위성을 활용한 위성 통신용 공공 테스트베드 운용에 관한 연구)

  • Wang, Do-Huy;Oh, Deock-Gil
    • Journal of Satellite, Information and Communications
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    • v.8 no.4
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    • pp.12-16
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    • 2013
  • This paper we introduce operated public test-bed satellite system configuration for satellite communications and usage for services via COMS(Communication, Ocean and Meteorological Satellite). According to trial public test-bed operation, the broadband multimedia services are expected to be available at the next generation VSAT services due to the increasing of Ka-band utilization. In addition, UHD broadcasting services via satellite is expected to improve the universal accessibility of broadcast services.

Studies on Applying Scalable Video Coding Signals to Ka band Satellite HDTV Service (SVC 신호의 Ka대역 HDTV 위성방송서비스 적용에 관한 연구)

  • Yoon, Ki-Chang;Chang, Dae-Ig;Sohn, Won
    • Journal of Broadcast Engineering
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    • v.13 no.6
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    • pp.905-914
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    • 2008
  • The paper studied the scheme of applying the MPEG-4 SVC signal to the Ka band satellite broadcasting system through the JSCC system to resolve the rain fading problem generated when providing the Ka band HDTV satellite broadcasting service. The Ka band satellite broadcasting system is based on the VCM mode of the DVB-S2, and the SVC signal is considered as one of the spatial scalability, the SNR scalability and the temporal scalability. The JSCC system jointed all the layers of the source coding system and the channel coding system, and allocated bit rate to source coding and channel coding for each layer to get the optimum receiving quality. The layers are consists of a base layer and an enhancement layer, and the bit rate of each layer is affected by the SVC signal. The applicability of the three SVC signals to the Ka band satellite broadcasting service is analyzed with respect to the rain fading, and the scheme of applying the most excellent SVC to the service is considered.

TCP Accelerator for DVB-RCS SATCOM Dynamic Bandwidth Environment with HAIPE

  • Kronewitter, F. Dell;Ryu, Bo;Zhang, Zhensheng;Ma, Liangping
    • Journal of Communications and Networks
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    • v.13 no.5
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    • pp.518-524
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    • 2011
  • A high assurance IP encryption (HAIPE) compliant protocol accelerator is proposed for military networks consisting of red (or classified) networks and black (or unclassified) networks. The boundary between red and black sides is assumed to be protected via a HAIPE device. However, the IP layer encryption introduces challenges for bandwidth on demand satellite communication. The problems experienced by transmission control protocol (TCP) over satellites are well understood: While standard modems (on the black side) employ TCP performance enhancing proxy (PEP) which has been shown to work well, the HAIPE encryption of TCP headers renders the onboard modem's PEP ineffective. This is attributed to the fact that under the bandwidth-on-demand environment, PEP must use traditional TCP mechanisms such as slow start to probe for the available bandwidth of the link (which eliminates the usefulness of the PEP). Most implementations recommend disabling the PEP when a HAIPE device is used. In this paper, we propose a novel solution, namely broadband HAIPE-embeddable satellite communications terminal (BHeST), which utilizes dynamic network performance enhancement algorithms for high latency bandwidth-on-demand satellite links protected by HAIPE. By moving the PEP into the red network and exploiting the explicit congestion notification bypass mechanism allowed by the latest HAIPE standard, we have been able to regain PEP's desired network enhancement that was lost due to HAIPE encryption (even though the idea of deploying PEP at the modem side is not new). Our BHeST solution employs direct video broadcast-return channel service (DVB-RCS), an open standard as a means of providing bandwidth-on-demand satellite links. Another issue we address is the estimation of current satellite bandwidth allocated to a remote terminal which is not available in DVBRCS. Simulation results show that the improvement of our solution over FIX PEP is significant and could reach up to 100%. The improvement over the original TCP is even more (up to 500% for certain configurations).

Novel Compressed Sensing Techniques for Realistic Image (실감 영상을 위한 압축 센싱 기법)

  • Lee, Sun Yui;Jung, Kuk Hyun;Kim, Jin Young;Park, Gooman
    • Journal of Satellite, Information and Communications
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    • v.9 no.3
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    • pp.59-63
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    • 2014
  • This paper describes the basic principles of 3D broadcast system and proposes new 3D broadcast technology that reduces the amount of data by applying CS(Compressed Sensing). Differences between Sampling theory and the CS technology concept were described. Recently proposed CS algorithm AMP(Approximate Message Passing) and CoSaMP(Compressive Sampling Matched Pursuit) were described. This paper compared an accuracy between two algorithms and a calculation time that image data compressed and restored by these algorithms. As result determines a low complexity algorithm for 3D broadcast system.