• Journal of Satellite, Information and Communications
• /
• v.3 no.2
• /
• pp.38-42
• /
• 2008

In 2005, DVB-S2 spec. was finalized. But with a large number of DVB-S receivers already installed, backwards compatibility may be required for a period of time, where old receivers continue to receive the same capacity as before, while the new DVB-S2 receivers could receive additional capacity broadcasts. To facilitate the reception of DVB-S serviced by DVB-S2 receivers, implementation of DVB-S in DVB-S2 chips is highly recommended. For the backward compatibility the system adapt the hierarchical modulation scheme. And the system has to meet system margin, so in this paper analyzes the effect according to the deviation angle and shows the BER performance. And finally this paper shows the result of the system implement using FPGA chip.

• Journal of Navigation and Port Research
• /
• v.38 no.3
• /
• pp.211-216
• /
• 2014

In this paper, high throughput method is studied to provide floating objects with broadband service as ship by using satellite. In recent, satellite broadcastings standard is based on DVB-S3 for communication service using wireless device on navigation communication by satellite. LDPC codes are iterative coding algorithm proposed in DVB-S3. In this paper, FTN technique is applied to LDPC codes with 8-PSK modulation and then present the method to alleviate performance degradation due to FTN through BICM-ID. BICM-ID is the method to improve performance by calculating a new LLR from hard-decision value of decoder output. DVB-S2 system with 8-PSK modulation and FTN technique based on iterative decoding had a better performance than DVB-S2 with 8-PSK modulation and FTN technique over Gaussian channels.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.45 no.2
• /
• pp.118-124
• /
• 2008

For forward error correction, DVB-S2, which is the digital video broadcasting forward error coding and modulation standard for satellite television, uses a system based the concatenation of BCH with LDPC inner coding. In DVB-S2 the LDPC codes are defined for 11 different code rates, which means that a DVB-S2 LDPC decoder should support multiple code rates. Seven of the 11 code rates, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, and 9/10, are regular and the rest four code rates, 1/4, 1/3, 2/5, and 1/2, are irregular. In this paper we propose a flexible decoder for the regular LDPC codes. We combined the partially parallel decoding architecture that has the advantages in the chip size, the memory efficiency, and the processing rate with Benes network to implement a DVB-S2 LDPC decoder that can support multiple code rates with a block size of 64,800 and can configure the interconnection between the variable nodes and the check nodes according to the parity-check matrix. The proposed decoder runs correctly at the frequency of 200MHz enabling 193.2Mbps decoding throughput. The area of the proposed decoder is $16.261m^2$ and the power dissipation is 198mW at a power supply voltage of 1.5V.

• Journal of the Korean Chemical Society
• /
• v.29 no.2
• /
• pp.164-171
• /
• 1985

The salicylic acid-formaldehyde condensed copolymer (SAF) and the 3-carboxy-4-hydroxy benzyl methacrylate divinylbenzene copolymer (CHBM-DVB) were synthesized. The capacities of SAF and CHBM-DVB ion exchangers were 4.6meq/g and 3.9 meq/g, respectively. The adsorption of several heavy metal ions on these weakly acidic ion exchangers and the property of ion exchanger were discussed. The distribution coefficients in hydrochloric acid solution and the elution behavior of several heavy metal ions were also discussed.

• Membrane Journal
• /
• v.6 no.4
• /
• pp.273-283
• /
• 1996

A cation-exchange membranes were prepared by polystyrene and poly(sodium 4-styrene sulfonate). The degree of crosslinking of polystyrene membranes was controlled by DVB. At the same time, the structure of PS membranes was changed from RO to MF by varying the concentration of PSS in the casting solution. Water flux increased with PS-PSS membranes due to the sulfonate groups, and final membrane cast from the solution containing 5% of DVB and 3% of PSS showed MF structure.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2000.11a
• /
• pp.139-148
• /
• 2000

국내 데이터방송 프로토콜 표준안 요약 .국제규격과의 호환성을 유지하기 위해 지상파(ATSC)와 위성(DVB) 규격을 별도로 정함. - 지상파 .T3/S13 : ATSC Data Broadcasting Standard .T3/S8 : PSIP(Program and System Information Protoc이) - 위성 .ETSI SN 301 192 : DVB Specification for Data B Broadcasting .ETSI EN 300 468 : Specification for SI(Service Information) i in DVB Systems 국내 규격 고유의 기능인 한글 처리 부분을 보완 또는 추가함 .

• Broadcasting and Media Magazine
• /
• v.13 no.3
• /
• pp.22-35
• /
• 2008

• Broadcasting and Media Magazine
• /
• v.13 no.3
• /
• pp.4-21
• /
• 2008

• Broadcasting and Media Magazine
• /
• v.13 no.3
• /
• pp.36-48
• /
• 2008

• Information and Communications Magazine
• /
• v.26 no.10
• /
• pp.3-10
• /
• 2009

본 논문에서는 2009년 5월부터 유럽 DVB (Digital Video Broadcasting)를 중심으로 본격적으로 진행되고 있는 차세대 VSAT(Very Small Aperture Terminal) 시스템 표준기술인 DVB-RCS (Return Channel via Satellite) NG(Next Generation) 표준의 시스템 및 서비스 개요와 표준화 ad-hoc 기술 그룹회의에서 제안된 기술들에 대해서 소개하고자 한다. DVB-RCS NG 표준은 2008년 5월부터 DVB-RCS CM (Commercial Module)과 시스템 interoperability 테스트 관할 협의체인 유럽의 Satlabs를 중심으로 새로운 규격 작업을 위한 상업적 요구사항 선정 및 구체적인 서비스/시스템 모델을 수립하였다. DVB-TM (Technical Module)과 CM을 거쳐 최종적으로 SB(Steering Board)에서 2008년 10월에 승인을 받고 RCS ad-hoc 그룹은 study mission을 수행하게 되었다. 2008년 11월부터 DVB-RCS NG 규격을 위한 call for technology 작업, 제안된 기술에 대한 평가 방법, 이를 평가하기 위한 system그룹 및 study 그룹이 결성되어 2009년 1월에 call for technology가 공지되고 2009년 5월 4일까지 20개 기관으로부터 19개의 기고서가 제출되었다. 본 고에서는2009년 7월 회의까지 검토된 후보기술에 대한 소개와 향후, RCS NG 표준에서 유망한 기술에 대하여 다루고자한다.