Journal of Broadcast Engineering (방송공학회논문지)

The Korean Institute of Broadcast and Media Engineers (한국방송∙미디어공학회)
권호 표지
DOI QR코드

DOI QR Code

Channel Estimation in E-OCR for T-DMB System

T-DMB 시스템을 위한 E-OCR에서의 채널추정

  • 박성익 (한국전자통신연구원 방송시스템연구부) ;
  • 임형수 (한국전자통신연구원 방송시스템연구부) ;
  • 김흥묵 (한국전자통신연구원 방송시스템연구부) ;
  • 오왕록 (한국전자통신연구원 방송시스템연구부)
  • Published : 2008.09.30
Download PDF
⟨ Previous Next ⟩

Abstract

This paper proposes noise reduction methods to improve the channel estimation performance in Equalization On-Channel Repeater (E-OCR) for Terrestrial-Digital Multimedia Broadcasting (T-DMB) system. In the E-OCR for T-DMB system, the channel estimation is performed by the pilot signal extraction and the channel coefficient estimation. Since the performance of the channel estimation highly depends on the estimated channel coefficients whose accuracy is associated with the received signal-to-noise ratio (SNR), it is important to reduce noise existing at the estimated channel coefficients. To reduce such noise components, various noise reduction methods of the estimated channel coefficients based on the M -point weighted moving average are proposed. Computer simulations show that the proposed methods improve the estimation performance by more than 2 to 3 dB in terms of the symbol error rate after equalization.

본 논문에서는 T-DMB (Terrestrial-Digital Multimedia Broadcasting) 시스템을 위한 E-OCR (Equalization On-Channel Repeater)에서의 채널추정 성능향상을 위한 잡음감소 기법을 제안한다. 일반적으로 E-OCR에서의 채널추정은 파일럿 신호 추출과 채널계수 추정에 의해 수행된다. 채널추정의 성능은 수신 SNR (Signal to Noise Ratio)과 연관되어 추정된 채널계수에 남아있는 잡음성분에 의해 결정되기 때문에, 잔존하는 잡음성분을 감소시키는 것은 매우 중요하다. 이러한 잡음성분을 감소시키기 위해, 주파수 영역에서의 M -point 가중이동평균(weighted moving average)을 기반으로 한 잡음제거 기법을 제안한다. 전산 실험에 의하면, 제안된 방법은 등화 후 SER (Symbol Error Rate) 측면에서 기존의 방법에 비해 2-3 dB의 성능 향상을 보인다.

Keywords

References

  1. Anders Mattsson, "Single Frequency Networks in DTV," IEEE Transactions on Broadcasting, vol. 51, no. 4, pp 413-422, Dec. 2005 https://doi.org/10.1109/TBC.2005.858419
  2. K. Salehian, M. Guillet, B. Carson, and A. Kennedy, "On-Channel Repeater for Digital Television Broadcasting Service," IEEE Transactions on Broadcasting, vol. 48, no. 2, pp. 97-102, June 2002 https://doi.org/10.1109/TBC.2002.1021274
  3. ETSI, "Digital Video Broadcasting (DVB); DVB Mega-Frame For Single Frequency Network (SFN) Synchronization," TS 101 191 v1.1.1, April 1997
  4. 박성익, 박소라, 음호민, 이용태, 김흥묵, "T-DMB의 SFN을 위한 등화형 동일채널 중계기," 방송공학회논문지, 제13권, 제3호, pp. 365-379, 2008년 https://doi.org/10.5909/JBE.2008.13.3.365
  5. Y. Zhao and A. Huang, "A Novel Channel Estimation Method for OFDM Mobile Communication Systems Based on Pilot Signals and Transform-Domain Processing," in IEEE 47th Vehicular Technology Conference, vol. 3, pp. 2089-2093, May 1997
  6. Y.-S. Lee, H.-N. Kim, S. I. Park, and S. I. Lee, "Noise Reduction for Channel Estimation Based on Pilot-Block Averaging in DVB-T Receivers," IEEE Trans. On Consumer Electronics, vol. 52, no. 1, pp. 51-58, Feb. 2006
  7. M. Hsieh and C. Wei, "Channel Estimation For OFDM Systems Based On Comb-Type Pilot Arrangement In Frequency Selective Fading Channels," IEEE Trans. On Consumer Electronics, vol. 46, no. 7, pp. 931-939, Jul. 1998
  8. X. Wang, Y. Wu, J.-Y. Chouinard, S. Lu, and B. Caron, "A Channel Characterization Technique Using Frequency Domain Pilot Time Domain Correlation Method For DVB-T Systems," IEEE Trans. On Consumer Electronics, vol. 49, pp. 949-957, Nov. 2003 https://doi.org/10.1109/TCE.2003.1261180
  9. Thomas M. Lehmann, Claudia Conner, Klaus Spitzer, "Survey: Interpolation Methods in Medical Image Processing," IEEE Trans. On Medical Imaging, vol. 18, No. 11, November 1999
  10. 김상진, "OFDM 시스템에서 이동평균필터를 이용한 LS 채널 추정 기법의 성능 분석," 연세대학교 대학원, 2005년
  11. Y.-T. Lee, S. I. Park, H. M. Eum. J. H. Seo, H. M. Kim, S. W. Kim, and J. S. Seo, "A Design of Equalization Digital On-Channel Repeater for the Single Frequency Networks," IEEE Trans. on Broadcasting, Vol. 53, No. 1, pp. 23-37, March 2007 https://doi.org/10.1109/TBC.2006.886453
  12. Mackenzie, ABERT, and SET, "General description of laboratory tests," DTV Field Test Report in Brazil, July 2000
  13. ETSI, "Radio Broadcasting Systems; Digital Audio Broadcasting (DAB) To Mobile, Portable And Fixed Receivers," ETSI EN 300 401 v1.3.3, Sept. 2001