• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.8A
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• pp.771-778
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• 2002

We investigate the design of an interpolation filter of a MF-TDMA demodulator which is applied to DVB-RCS. If sampling is not synchronized to the data symbols, timing adjustment in digital receiver must be performed by interpolation. It is impossible that conventional sinc interpolation filter coefficients are actually extended to infinity. We propose a Kaiser window interpolation filter and a sinc interpolation filter using th Kaiser window. Simulation results show that the performance improvement is realized by employing the proposed interpolation filter.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.11
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• pp.4419-4435
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• 2015

The use of an efficient packet scheduling scheme for a forward link in satellite communication networks is very important to support fairness for each return channel satellite terminal (RCST) and the service differentiations for user traffics. To support fairness and QoS for each RCST with service-level agreement (SLA), the Adaptive Coding and Modulation (ACM) system in a satellite hub has to process packets with considering modulation and coding (MODCOD) and packet types. Although a DVB-S2 system with ACM scheme has higher transmission efficiency, it cannot offer fairness or quality of service (QoS) to RCSTs. Because the data are transmitted with high MODCOD in regions with clear skies, while data are transmitted using low MODCOD in regions experiencing rain events. In this paper, we propose a two-step scheduling scheme offering fairness and QoS to RCSTs, while minimizing a decrease in throughput. The proposed scheme is carried out performance evaluations using a computer simulation. As results of this simulation, the proposed scheduler was shown to support bandwidth fairness to an individual RCST, and provide a level of QoS differentiation for user traffics.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.5
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• pp.12-20
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• 1999

본 논문에서는 DVB-T (digital video broadcasting-terrestrial) 수신기의 동기화 알고리듬과 각 동기단 사이의 연동 알고리듬을 제안한다. OFDM( orthohonal frequency division multiplexing) 수신단에서는 프레임 동기, 반송파 동기, 심볼 타이밍 동기가 요구되어진다. 기존의 반송파 동기 방법은 부반송파 간격의 정수배 주파수 옵셋 보상 후 잔존해 있는 주파수 옵셋이 -0.5×(부반송파 간격) 혹은 +0.5×(부반송파 간격)에 가까운 값을 가질 때 많은 시간이 소요되는 문제점을 가지고 있다. 본 논문에서는 시스템의 복잡도를 그대로 유지 하면서 초기 동기화 시간을 줄일 수 있는 반송파 동기 알고리듬을 제안한다. 그리고 DVB-T모드를 추정하는 알고리듬을 제안하고 반송파 동기 추적루프와 심볼 타이밍 동기 추적루프를 동시에 동작시킴으로써 초기 동기화 시간을 추가적으로 줄일 수 있는 심볼 타이ALD 동기 알고리듬을 제안한다. 그리고 전체 수신기 모델의 연동 방안을 제시한다.

• Electronics and Telecommunications Trends
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• v.23 no.3
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• pp.130-137
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• 2008

최근 위성방송 기술은 고선명/고음질을 실현하고, 다양한 부가서비스를 제공하는 고품질의 디지털 전송방식으로 변화하고 있다. 이러한 위성방송의 수요확대에 다채널 데이터 전송 및 HD급 고품질의 영상을 전송할 수 있는 DVB-S2 시스템 개발에 한창이다. 본 논문에서는 DVB-S2 전송방식을 적용하기 위한 Ku-Ka 대역의 강우감쇠 등을 효과적으로 보상하여 보다 나은 위성방송 수신 가용도를 높이기 위한 방안에 대해 논한다.

• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.51-55
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• 2006

Digital satellite communication systems are usually integrated with terrestrial systems to provide various services. In these cases, they should satisfy the performance objectives defined by the terrestrial systems. Recommendation ITU-R S.1062 specifies the error performance objectives of digital satellite communication systems operating below 15 GHz. The error performance are given in terms of bit error probability divided by the number of the average bit errors in the burst ($\alpha$). This paper presents a theoretical method to estimate $\alpha$ that is a very important parameter in the satellite communication systems to analyze the error performance objectives. We show performance estimation result of DVB-RCS turbo code using the presented method, and verify them by comparing to the simulation results.

• Convergence Security Journal
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• v.22 no.2
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• pp.91-98
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• 2022

Because the movie has the characteristics of a cultural product where experience is important, a promotional strategy is used to convert viewers into movie audiences by providing indirect experiences of movies through professional movie information programs. Considering that the movie information program is a strategic publicity medium that raises the audience's intention to watch a movie, a study on the data service that provides useful additional information to the viewer in conjunction with the movie information program is meaningful. Against this background, this study contains the core research contents in the development of data service linked with movie information program. Specifically, additional information of the movie information program was defined. And to provide the additional information to the data service, the digital broadcasting international standard DVB-SI-based additional information transmission method was devised.

• Convergence Security Journal
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• v.23 no.3
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• pp.57-64
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• 2023

Due to the COVID-19 pandemic, the broadcasting industry has been greatly affected, to the extent that the footprint of travel programs has disappeared. Although travel programs have been back on the air since 2022, there remains a task of recovering the stagnant desire for travel. Based on a study that travel programs have a positive impact on viewers' travel intentions, this study examined a data service that provides preferred additional information on travel programs, considering the broadcasting environment of satellite broadcasters that transmit multiple travel programs through various channels. Specifically, preferred additional information was investigated for travel programs of various genres and formats, and a feature model based on FODA was designed to be used when the satellite broadcaster decides the data service configuration. In addition, the necessary information for operating the data service was defined based on the feature model, and a method of transmitting it using the DVB-S SI, a domestic satellite broadcasting standard, was devised. The feasibility of this study was also confirmed using a DVB-MHP based data service prototype.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.373-379
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• 2005

The volatile components of Pinus densiflora needles were studied by gas chromatography-mass spectrometry(GC-MS), using seven kinds of solid phase microextraction (SPME) fibers, seven in SPME fibers: 100 ${\mu}m$ PDMS, 65 ${\mu}m$ PDMS/DVB, 65 ${\mu}m$ SF-PDMS/DVB, 85 ${\mu}m$ PA, 75 ${\mu}m$ CAR/PDMS, 65 ${\mu}m$ CW/DVB and 50/30 ${\mu}m$ DVB/CAR/PDMS fibers. A total of 40 components were identified by using the seven different SPME fibers. The identified components were classified, according to their functionalities, as follows: 26 hydro-carbons, 7 alcohols, 4 carbonyl compounds, and 3 esters. The major volatile components of Pinus densiflora needles identified by these SPME fibers were $\alpha$-pinene ($1.7\~21.7\;{\mu}g/g$), $\beta$-myrcene ($2.0\~20.1\;{\mu}g/g$), $\beta$-phel-landrene ($4.6\~22.8\;{\mu}g/g$), $\beta$-caryophyllene ($6.7\~26.0\;{\mu}g/g$) germacrene D ($1.1\~11.9\;{\mu}g/g$). In the comparison of the seven SPME fibers, PDMS appeared to be the most suitable fiber for the analysis of hydrocarbon compounds and CAR/DPMS, PDMS/DVB, CW/VB and DVB/CAR/PDMS are shown to be optimal for analysis of the alcohols and carbonyl compounds.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.2
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• pp.223-228
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• 2007

The Digital Frequency Synthesizer(DFS) that generates the wideband signal with high speed frequency hopping rate and high frequency resolution characteristics was designed and implemented in this paper The DFS was applied as local oscillator for direct frequency conversion IF modules of DVB-RCS, which directly generates the transmission immediate frequency signal by using DDS and wideband PLL technologies. The DDS technology provides high speed frequency hopping rate and high frequency resolution characteristics, which are also the DVB-RCS requirement. The wideband PLL technology also provides the wideband signal generation, which is a necessity for direct frequency conversion modules. The implemented DFS provides the spurious suppression characteristic of -50 dBc and less, frequency resolution of 0.233 Hz and frequency hopping rate of 125 ns, respectively. Also the DFS represents the amplitude flatness of 3 dB and less in the pass-band, and phase noise characteristic of -75 dBc/Hz at 1 kHz frequency offset.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.4
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• pp.64-71
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• 2009

This paper presents an efficient frame synchronizer architecture using the common autocorrelator for Digital Video Broadcasting via Satellite, Second generation(DVB-S2). To achieve the satisfactory performance under severe channel conditions and the efficient hardware resource utilization of functional synchronization blocks which have been implemented, we propose a new efficient common autocorrelator structure. The proposed architecture can improve the performance of the frame and frequency synchronizer since each block operates jointly in parallel and significantly reduce the complexity of the frame synchronizer. Hence, The proposed architecture can ensure the decrease by about 92% multipliers and 81% adders compared with the direct implementation. Moreover, it has been thoroughly verified with an FPGA board and R&STM SFU broadcast test equipment and consists of 29,821 LUTs with XilinxTM Virtex IV LX200.