• Title/Summary/Keyword: Convolutional coder

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Comparison between 8PSK-TCM and QPSK of BER (8PSK-TCM과 QPSK의 BER 비교)

  • Wu, Bin-Bin;Suh, Hee-Jong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.7 no.1
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    • pp.39-44
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    • 2012
  • In this paper, we studied a high speed Trellis Coded Modulation (TCM) system and 8PSK-TCM system, and compare 8PSK-TCM system with QPSK system of BER. We know that 8PSK-TCM had 3 db improvement of BER than QPSK. And we demonstrated the superiority of 8PSK-TCM by simulating with Matlab. Input signal was 2 bits long, and 8PSK-TCM used 3bits long. Results of this simulation said that 8PSK-TCM had 3 db improvement of BER than QPSK.

A study of next generation OpenCable systems for Ultra-High Definition television broadcasting (초 고화질 텔레비전 방송을 위한 차세대 오픈 케이블 방식에 대한 연구)

  • Cho, Chang-Yeon;Heo, Jun;Kim, Joon-Tae
    • Journal of Broadcast Engineering
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    • v.14 no.2
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    • pp.228-237
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    • 2009
  • This paper examines the potential of Ultra-High Definition TV (UD-TV) broadcasting transmission systems beyond HD-TV over cable channel. Firstly, we analyze the trend of TOV(Threshold of Visibility) by extending the OpenCable (J.83 Annex B) system 256QAM which is the standard of Korean and American cable television transmission to 1024QAM, and realize that the OpenCable 1024QAM has nearly 30% higher data rate than 256QAM at the expense of impractically higher TOV (Threshold of Visibility). To achieve practical TOV, we control code rates of inner convolutional coder and replace turbo coder in forward error correction (FEC) part, thereby analyzing the best performance of the OpenCable systems having conventional FEC. In that result, it is necessary to modify conventional FEC of the OpenCable system to achieve under 31.5dB TOV. Moreover we study the potential of UD-TV transmission via two or more TV channels, so called channel bonding, through the Shannon capacity in 6MHz channel and the relationship with next generation A/V codec technologies.