• 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 the Institute of Electronics Engineers of Korea TC
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• v.49 no.8
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• pp.33-38
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• 2012

An equalization algorithm is proposed for digital video broadcasting - terrestrial version 2 (DVB-T2) systems to minimize the noise effect. It is done by averaging frequency-domain data and channel responses obtained with different signal intervals for the same orthogonal frequency division multiplexing (OFDM) symbol. Its performance is evaluated by computer simulations along with comparison of conventional algorithms.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.11a
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• pp.21-22
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• 2014

3D 방송서비스를 위해 다양한 방식이 제안되어 왔으며 최근에는 주파수 효율성을 극대화한 방식인 고정 및 이동 방송 융합형 3DTV 방송 방식이 북미 표준으로 채택되었다. 고정 및 이동 방송 융합형 3DTV 방송 방식은 기존의 고정 방송 및 이동 방송망을 활용하여 좌안 영상과 우안 영상 스트림을 전송하는 방식이며, 3D 방송서비스 제공을 위해 별도의 주파수 할당을 할 필요가 없으므로 높은 주파수 효율성을 제공할 수 있다. 본 논문에서는 ATSC의 고정 및 이동 방송 규격과 DVB T2의 고정 및 이동 방송 규격의 차이를 시그널링 정보 전송 관점에서 분석하고 고정 및 이동 방송 융합형 3DTV 서비스를 DVB T2 방송환경에서 제공하기 위한 시그널링 방식을 제안한다.

• Journal of Advanced Navigation Technology
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• v.15 no.4
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• pp.591-595
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• 2011

In this paper, we design the hardware architecture of the BICM(Bit Interleaved Coded Modulation) module for next generation European broadcast system and implement the BICM module with DSP(Digital Signal Processor) TMS320C6474. Simulation result shows that the BER(Bit Error Rate) performance of the fixed-point BICM module using more than 8 bits is very similar to that of the floating-point BICM module.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.11a
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• pp.71-74
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• 2012

본 논문에서는 현재의 HDTV와 3DTV보다 4배 이상 초고화질의 UHDTV와 Full-HD급 3DTV 등 지상파에서의 차세대방송 구현 가능성을 DVB-T2 전송방식과 HEVC 압축방식을 기반으로 설명한다. 4K 혹은 8K-UHDTV 대용량 데이터전송을 위하여 일본과 여러 나라에서 새로운 전송기술을 연구 중이지만 여기서는 현재 상용화된 기술 중 DVB-T2 전송기술을 중심으로 자료를 통하여 가능성을 알아본다. 지상파방송 디지털전환에 이어 또다시 차세대방송을 위한 전환의 성공조건으로 UHDTV와 3DTV전송도 중요하지만 시청자 직접수신과 실내수신 및 언제 어디서나 자유로운 수신환경 제공도 매우 중요하다. 그러므로 본 논문에서는 효율적인 주파수 활용과 수신능률 향상을 위하여 VHF대역과 UHF 700MJHz대역 등 2개의 서로 다른 주파수 대역을 이용한 SFN 송출망의 효과를 제시하고, 소출력 Gap Filler 및 가정용 SFN Gap Filler를 활용한 자유로운 수신환경 구성을 제안하고 있다.

• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.55-59
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• 2003

In this paper, we estimate the performance requirements of general-purpose DSP for Carrier Recovery of OFDM DVB-T receiver. Firstly, we transported the designed fixed-point OFDM DVB-T model to a floating-point software model written in C. Then, we measured the number of instruction cycles required for operation of Carrier Recovery in time. We use SignalMaster$\^$TM/ DSP platform of LYRtech Inc. as a environment of estimation, and Simulink$\^$TM/ as a graphical interface, Code Composer StudioTM of TI as profiler and compiler, and SPW$\^$TM/ for presenting functional reliability and comparing the performance distortion with fixed-point model. As a result, we show the required number of DSPs in our DSP-based system, and introduce the need of Multi-DSP-based system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.4
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• pp.151-156
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• 2010

In this paper, several computer simulations are investigated to confirm the DVB-H system performance and to find proper single frequency network cell coverage. From the result, we confirm that 2K mode transmission is more robust to Doppler frequency than 8K mode. The result of this paper can be partially applied to the design the single frequency network.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.1-7
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• 2012

In this paper, we was performed the interference analysis to determine an optimal coexisting criteria for the european digital video broadcasting service (DVB-T2) and the IMT-advanced LTE based TV Band Device (TVBD). The TVBD was equipped with the spectrum cognition method. To this end, we set the various transmission parameters, that includes the emission and blocking mask, antenna height and gain, transmission power and bandwidth, channel model etc. Based on this parameters, we were calculated the allowable transmit power, the number of TVBD and the change in probability of interference for the TVBD user operating in the adjacent channels of the DVB-T2 user. Also this paper presents how many TVBD users can sharing with DVB-T2 for spectral cognition performance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.4
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• pp.195-205
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• 2014

The ultra-high definition television (UHDTV) has been considered as a next generation broadcsating service. However the conventional digital terrestrial transmission system cannot afford the required transmission data rate of UHDTV, and thus adopting ultra-high order constellation, such as 4096-QAM, into the conventional DTT systems has been studied. In particular, when the ultra-high order constellation is adopted into the digital video broadcasting-2nd generation terrestrial (DVB-T2) unequal-error protection (UEP) properties of a codeword of an error correction coding and ultra-high order constellations should be properly matched by bit mapper in order to enhance the decoding performance. Because long codeword results in a heavy computational complexity to design the bit mapper, the DVB-T2 divided it into cascaded blocks, the bit interleaver and the bit-to-cell DEMUX, and there have been many researches related to each block. However, there are few published study related to design methodology of bit interleaver. In this respect, this paper proposes a design methodology of the bit interleaver and presents bit interleavers of 1024-QAM and 4096-QAM according to the proposed design algorithm. The newly designed interleavers improved the decoding performance of the error correction coding by maximally 0.6 dB SNR over both of AWGN and random fading channel.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.9
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• pp.817-825
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• 2013

The UHDTV system, which provides realistic service with ultra-high definite video and multi-channel audio, has been studied as a next generation broadcasting service. Since the conventional digital terrestrial transmission system is not capable to cover the increased transmission data rate of the UHDTV service, there are great necessity of researches about increase of data rate. Accordingly, the researches has been studied to increase the transmission data rate of the DVB-T2 system using dual-polarized MIMO technique and high order modulation. In order to optimize the MIMO DVB-T2 system where irregular LDPC codes are used, it is necessary to study the design of the bit mapper that matches the LDPC code and QAM symbols in MIMO channel. However, the research related to the design of the bit mapper has been limited to the SISO system. Therefore, this paper defines a new parameter that indicates the VND distribution of MIMO DVB-T2 system and performs the performance analysis according to the parameter which will be helpful for designing a MIMO bit mapper.