• Information and Communications Magazine
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• v.30 no.5
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• pp.59-67
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• 2013

본고에서는 유럽의 모바일 방송 기술과 차세대 모바일 방송이 개발된 배경에 대해서 살펴보고 지상파 디지털 방송 표준인 DVB-T2를 기반으로 모바일 방송에 특화된 DVB-T2 Lite의 특징 및 차세대 모바일 방송 규격인DVB-NGH시스템에서 다루고 있는 다양한 프로파일들과 관련하여 세부 기술들에 대해 알아본다. 또한, 현 시점에서의 미래 디지털 방송 기술 발전에 대한 전망을 살펴보고자 한다.

• Broadcasting and Media Magazine
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• v.19 no.2
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• pp.36-45
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• 2014

With major sports events such as FIFA World Cup and The Olympic Games coming up, UHDTV technology has been given a major push by broadcasters, test and measurement (T&M), and consumer electronics (TV and set-top box) manufacturers. The increase in picture resolution ($3840{\times}2160$) for 4K and ($7680{\times}4320$) for 8K compared to current HDTV ($1920{\times}1080$), as well as the need to deliver these services in higher frame rates (50/60 up to 100/120fps) translate to a big challenge in UHDTV content delivery to households over terrestrial transmission due to higher data rates. DVB-T2 has been favored by many countries across the world as it is proven to give the best spectral efficiency for terrestrial broadcasting. On the other hand MPEG-4 appears to be the bottleneck for UHDTV since a much higher data rate is needed to deliver such services. Therefore HEVC becomes mandatory for UHDTV delivery over DVB-T2. In this paper, we will give an overview about a complete end-to-end solution for UHDTV delivery over DVB-T2 based on a realistic SFN scenario in Seoul metropolitan area.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.5C
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• pp.485-497
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• 2009

In this paper, we described DVB-S2 system for mobility. cross layer coding technique are needed to maintain the performance in deep fading channel. Cross layer coding is divided into two kinds of level. First level is Physical layer coding and, second layer is link layer or upper layer coding. Fixed on DVB-S2 short frame coding method as a physical layer, we simulated the various coding method as an upper layer coding. Furthermore, we analyzed the performance of each coding method on according to mobile vehicle speed, data rate, interleaving memory size, and IP packet size.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.2A
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• pp.91-97
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• 2008

In this paper, we propose a channel estimation method associated with the interpolation order for OFDM systems. We first analyze the time varying channel and frequency selective channels, and then derive the channel index which indicates the ratio of the time axis variation and the frequency axis variation. This index is used for determining the order of interpolation such as time axis followed by frequency axis interpolation or vice versa. The computer simulation over a DVB-T system shows that the proposed method can provide more accurate channel information, thereby improving the overall performance.

• Journal of Broadcast Engineering
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• v.18 no.4
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• pp.572-588
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• 2013

In this paper, 4K-UHDTV or 8K-UHDTV and UHD-3DTV that the next generation broadcasting implementation and the possibility of direct receiving environment construction is analyzed on the terrestrial broadcasting. Particularly, we investigated the possibility by analyzing the previous and related works with regard to UHDTV transmission by DVB-T2 that is one of the best commercialized transmission mode. In order that the UHDTV broadcasting succeeds once again after completion of digital terrestrial switch over at the end of 2012, the ultra high resolution image transfer is important. However, the direct, the indoor and ubiquitous receiving environment is important in not only TV but also the personal type multimedia terminal in the sense of UHDTV service penetration. Therefore, in this paper, by using SFN and high error-correcting mode in DVB-T2 standard, the efficient frequency utilization and effective reception environment construction is illustrated. Particularly, SFN network constitution by 2 mutually different frequencies including the VHF bandwidth and UHF band, and etc. is shown. And the method that builds the free wireless receive environment by using SFN low power radio repeater and for home use gap filler is proposed. And the effect and frequency amount required are presented, when UHDTV broadcasting use 10MHz bandwidth.

• Journal of Broadcast Engineering
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• v.21 no.4
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• pp.506-514
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• 2016

In this study, HEVC over DVB-T2 systems with a bandwidth of 6 MHz is considered, particularly for the terrestrial 4K-UHDTV broadcasting service in the Republic of Korea. The threshold of visibility carrier-to-noise power ratio (ToV C/N) and the receiver minimum required input level (sensitivity) for satisfying the subjective picture failure (SPF) condition are measured in the laboratory. It is observed, for transmitting 26.37 Mbps data stream correctly, that ToV C/N is 18.8 dB on average, and the receiver sensitivity is varied from minimum -84.2 dBm to maximum -80.0 dBm. Based on the results, the receiver noise floor is calculated by -100 dBm on average.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.2
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• pp.702-721
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• 2012

In the DVB-T2 system with a multiple-input single-output (MISO) transmission mode, Alamouti coded orthogonal frequency division multiplexing (OFDM) signals are transmitted simultaneously from two spatially separated transmitters in a single frequency network (SFN). In such systems, each transmit-receive link may have a distinct carrier frequency offset (CFO) due to the Doppler shift and/or frequency mismatch between the local oscillators. Thus, the received signal experiences dual CFOs. This not only causes dual phase errors in desired data but also introduces inter-carrier interference (ICI), which cannot be removed completely by simply performing a CFO compensation. To overcome this problem, this paper proposes an iterative detection with dual phase errors compensation technique. In addition, we propose a successive-iterative ICI cancellation technique. This technique successively eliminates ICI in the initial iteration by exploiting pre-detected data pairs. Then, in subsequent iterations, it performs a fine interference cancellation using a priori information, iteratively fed back from the channel decoder. In contrast to previous works, the proposed techniques do not require estimates of dual CFOs. Their performances are evaluated via a full DVB-T2 simulator. Simulation results show that the DVB-T2 receiver equipped with the proposed dual phase errors compensation and the successive-iterative ICI cancellation techniques achieves almost the same performance as ideal dual CFOs-free systems, even for large dual CFOs.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.540-543
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• 2008

본 논문은 DVB-T 전송스트림의 비디오, 오디오 및 그 외의 데이터의 다중화를 고찰하고, 효율적인 역다중화에 대한 연구이다. DVB 시스템은 위성, 케이블, 지상파, 휴대용 등 모든 전송 매체에 디지털 TV 및 데이터 방송을 제공하며 전송(Transport) 시스템으로 MPEG-2 시스템을 채택하였다. MPEG-2 시스템은 여러 가지 영상과 음성, 데이터 스트림을 하나의 스트림으로 다중화하고 188byte 크기의 전송 스트림 패킷을 사용한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2005.11a
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• pp.87-90
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• 2005

이 연구는 DVB에서 제안한 휴대형 디지털 TV 전송시스템인 DVB-H 시스템의 이동수신 성능을 분석하였다. DVB-H 시스템은 DVB-T 시스템을 휴대용으로 보완한 것으로 4K 모드, MPE-FEC 및 In-depth Interleaver 등이 추가되었으며, 이 연구는 각 추가 기능에 대하여 이동수신 성능향상 정도를 분석하였다. 이동수신 환경을 제공하기 위하여 COST 207을 적용하였다. 4K 모드는 최대지연시간이 긴 다중경로채널에서 8K 모드와 유사하고 2K 모드보다 훨씬 우수한 수신성능을 보였으며 도플러에 대해서는 2K와 8K 모드의 중간정도의 수신성능을 보여 주었다. MPE-FEC와 In-depth Interleaver는 이동수신채널에서 약간의 수신성능 향상을 보여 주었다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.8
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• pp.60-64
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• 2007

In this paper, we designed FFT for European DTV and implemented system with Stratix EP1S25F672C6 FPGA At the implemented FFT, we used SIC architecture. SIC architecture is composed of algorithm-specific processing element, RAM memory, registers, and a central or distributed control unit. Designed FFT was acceptable either 2K or 8K point FFT processing, and is selectable guard interval such as 1/4, 1/8, 1/16, 1/32. Consequently, it was suitable for the standard of DVB-T(Digital Terrestrial Video Transmission System) specification. It resulted in 12% of total logic gate and 53% of total memory bit in Stratix device.