The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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Mitigation of Inter-Symbol Interference in Underwater Acoustic Communication Using Spatial Filter

공간 필터를 이용한 수중음향통신의 인접 심볼 간 간섭 완화

  • 엄민정 (한국해양대학교 해양공학과) ;
  • 박지성 (한국해양대학교 해양공학과) ;
  • 지윤희 (한국해양대학교 해양공학과) ;
  • 김재수 (한국해양대학교 해양공학과)
  • Received : 2013.10.04
  • Accepted : 2013.11.20
  • Published : 2014.01.31
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Abstract

The underwater acoustic communication (UAC) is characterized by doubly spread channel. It is included in the time-variant doppler shift and delay-time spreads due to multiple paths. To compensate such distorted signals, various techniques including time-reversal processing, spatial diversity, phase estimator, and equalizer are being applied. In this paper, a spatial filter based on the beamforming is proposed as a method to mitigate such inter-symbol interferences that are generated in time-varying multipath channels. The proposed technique realizes coherent communications by steering the direction of the desired signals and improves the performance of UAC by increasing the signal-to-interference plus noise ratio using the array gain.

수중음향통신은 시변동성으로 인하여 도플러 편이를 발생하고, 다중경로로 인하여 지연 확산의 특성을 갖는다. 이러한 채널 특성은 인접 심볼 간 간섭을 발생시켜 통신 성능을 저하시킨다. 통신 성능을 개선하기 위하여 시역전, 공간 다이버시티, 위상 추정기 및 등화기 등과 같은 다양한 기법이 연구되고 있다. 본 논문에서는 시변동성 다중경로로 인한 인접 심볼 간 간섭을 완화하는 방법으로 빔 형성 기반의 공간 필터 기법을 제안한다. 제안된 기법은 원하는 신호방향으로 빔을 조향하여 공간상의 신호를 분리하고, 배열 이득으로 신호 대 간섭 잡음비를 향상시키고 통신 성능을 개선한다.

Keywords

References

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