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50 kHz 체장어군탐지기용 분할 빔 음향 변환기의 지향성 보정 및 위치각 추정

Estimation of Angular Location and Directivity Compensation of Split-beam Acoustic Transducer for a 50 kHz Fish Sizing Echo Sounder

  • 이대재 (부경대학교 해양생산시스템관리학부)
  • Lee, Dae-Jae (Division of Marine Production System Management, Pukyong National University)
  • 투고 : 2011.04.12
  • 심사 : 2011.07.27
  • 발행 : 2011.08.30

초록

The most satisfactory split-beam transducer for fish sizing maintains a wide bearing angle region for correct fish tracking without interference from side lobes and lower sensitivity to fish echoes outside of the main lobe region to correctly measure the angular location of free-swimming fishes in the sound beam. To evaluate the performance of an experimentally developed 50 kHz split-beam transducer, the angular location of a target was derived from the electrical phase difference between the resultant signals for the pair of transducer quadrants in the horizontal and vertical planes consisting of 32 transducer elements. The electrical phase difference was calculated by cross-spectral density analysis for the signals from the pair of receiving transducer quadrants, and the directivity correction factor for a developed split-beam transducer was estimated as the fourth-order polynomial of the off-axis beam angle for the angular location of the target. The experimental results demonstrate that the distance between the acoustic centers for the pair of receiving transducer quadrants can be controlled to less than one wavelength by optimization with amplitude-weighting transformers, and a smaller center spacing provides a range of greater angular location for tracking of a fish target. In particular, a side lobe level of -25.2 dB and an intercenter spacing of $0.96\lambda$($\lambda$= wavelength) obtained in this study suggest that the angular location of fish targets distributing within a range of approximately ${\pm}28^{\circ}$ without interference from side lobes can be measured.

키워드

참고문헌

  1. Balanis CA. 1997. Anetenna Theory. John Wiley & Son Inc. New York, U.S.A., 294-306.
  2. Brede R, Kristensen FH, Solli H and Ona E. 1987. Target tracking with a split beam echo sounder. Int Sym on Fish Acoustics 87, 1-16.
  3. Foote KG. 1990. Designing an improved transducer array geometry. J Cons int Explor Mer 46, 129-132. https://doi.org/10.1093/icesjms/46.2.129
  4. Hans VS and Francis WZ. 2001. Statistical analysis in climate research. Cambridge University Press, London, U.K., 235-236.
  5. Hood CJ. 1987. Measurements of a split beam transducer. Int.Sym on Fish. Acoustics 87, 1-23.
  6. Lee DJ. 1999. Instrument engineering for fishing. Tae Hwa Publishing, Busan, Korea, 198-200.
  7. Lee DJ and Lee WS. 2010. Design, fabrication and performance characteristics of a 50kHz tonpilz type transducer with a half-wavelength diameter. J Kor Soc Fish Tech 46, 173-183. https://doi.org/10.3796/KSFT.2010.46.2.173
  8. Lee DJ and Lee WS. 2011. Development of 50kHz split-beam acoustic transducer for a fish sizing echo sounder. Kor J Fish Aquat Sci 44, 44-53.
  9. MacLeannan DN, Simmonds EJ. 1995. Fisheries Acoustics. Chaman & Hall, London. U.K., 45-88
  10. Malcolm JC. 1998. Handbook of acoustics. John Wiley & Sons Inc., New York, U.S.A., 1058-1059.
  11. Martyna M and Thomas B. 2010. Real Wages and the Business Cycle in Germany. IZA DP No 5199, 17-20.
  12. Park HY, Kim MJ, Lee DJ, Yoon JR and Kim CD. 2004. Split-beam method for fish finder using a band-limited sweep. Proceeding of ICA 2004, 759-760.
  13. Quaji AH. 1982. Array beam response in the presence of amplitude and phase fluctuations. J Acoust Soc Am 72 (1), 171-180. https://doi.org/10.1121/1.388001
  14. Ziomeck LJ. 1985. Underwater Acoustics. Academic Press, Inc., New York, U.S.A., 94-152.

피인용 문헌

  1. Bandwidth Enhancement of a Broadband Ultrasonic Mosaic Transducer using 48 Tonpilz Transducer Elements with 12 Resonance Frequencies vol.47, pp.3, 2014, https://doi.org/10.5657/KFAS.2014.0302
  2. Design and Development of a Broadband Ultrasonic Transducer Operating over the Frequency Range of 40 to 75 kHz vol.47, pp.3, 2014, https://doi.org/10.5657/KFAS.2014.0292