DOI QR코드

DOI QR Code

상용 모뎀 제어를 통한 수중 CSMA/CA 프로토콜 시험

Underwater Experiment on CSMA/CA Protocol Using Commercial Modems

  • 투고 : 2013.12.13
  • 심사 : 2014.05.30
  • 발행 : 2014.06.30

초록

본 논문에서는 수중음향센서네트워크의 수중 통신 프로토콜 시험을 위해 구축한 해상시험환경을 소개하고 상용 모뎀을 이용하여 실시한 및 매체접속제어기법(Medium Access Control: MAC)의 시험결과를 제시한다. 본 시험에서는 패킷 충돌을 회피하기 위해 기존 지상환경에서 많이 사용되는 반송파감지기반의 충돌회피기법(Carrier Sense Multiple Access/Collision Avoidance: CSMA/CA)을 사용하였으며 수중 통신 프로토콜로서의 가용성을 검증하였다. 시험에 사용된 네트워크 노드는 Benthos사의 상용 수중 모뎀과 ATmega2560 제어보드를 이용하여 구성하였다. 시험의 체계적 관리와 시험과정 관찰을 용이하게 하기 위해 각 노드가 GPS신호를 수신하여 자신의 위치를 파악할 수 있도록 하였으며 라디오주파수(Radio Frequency: RF) 인터페이스를 통해 위치정보 및 수중채널을 통해 송수신되는 패킷의 정보를 지상으로 보고할 수 있도록 했다. CSMA/CA 프로토콜을 수중환경에 적용하기 위해 4-way 핸드셰이킹동작에 사용되는 네 종류의 제어패킷 RTS(Request To Send), CTS(Clear to Send), DATA, ACK(Acknowledgement)을 수중환경에 맞게 설계했다. 시험을 통해 CSMA/CA 프로토콜의 실제 수중환경에서의 가용성을 검증할 수 있었다.

This paper introduces a test bed for communication protocol schemes of underwater acoustic sensor network, and also shows experimental results obtained from the test bed. As a testing protocol, carrier sense multiple access/collision avoidance (CSMA/CA) is evaluated on underwater acoustic channel. A sensor node is equipped with a DSP control board of ATmega2560 and a commercial underwater modem produced by Benthos. The control board not only manipulates a GPS signal to acquire the information of location and time, but also controls the underwater modem to operate according to the procedure designed for a given testing protocol. Whenever any event takes place such as exchanging control/data packets between underwater modems and acquiring location and timing information, each sensor node reports them through radio frequency (RF) air interface to a central station located on the ground. The four kinds of packets for CSMA/CA, RTS(Request To Send), CTS(Clear to Send), DATA, ACK(Acknowledgement) are designed according to the underwater communication environment and are analyzed through the lake experiment from the point of feasibility of CSMA/CA in underwater acoustic communications.

키워드

참고문헌

  1. K.-M. Kim and J.-W. Han, "Design of OFDM system for high speed data transmission in underwater," in Proc. IEEK summer Conf., pp 85-88, Pyungchang, Korea, Jun. 2008.
  2. J.-P. Kim, J.-W. Lee, Y.-S. Jang, K. Son, and H.-S. Cho, "A CDMA-based MAC protocol in tree-topology for underwater acoustic sensor networks," in Proc. IEEE WAINA, pp. 1166-1171, Bradford, UK, May 2009.
  3. M. Stojanovic and J. Preisig, "Underwater acoustic communication channels: propagation models and statistical characterization," IEEE Commun. Mag., vol. 47, no. 1, pp. 84-89, Jan. 2009.
  4. X. Guo, M. R. Frater, and N. J. Ryan, "An adaptive propagation-delay-tolerant mac protocol for underwater acoustic sensor networks," in Proc. MTS/IEEE OCEANS, pp. 1-5, Aberdeen, Scotland, Jun. 2007.
  5. D.-S. Shin and D.-K. Kim, "A dynamic NAV determination protocol in 802.11 based underwater networks," in Proc. IEEE ISWCS, pp. 401-405, Reykjavik, Iceland, Oct. 2008.
  6. D. Fang, Y. Li, H. Huang, and L, Yin, "A CSMA/CA-based MAC protocol for underwater acoustic networks," in Proc. IEEE WiCOM, pp. 1-4, Chengdu, China, Sept. 2010.
  7. Z. Peng, J.-H. Cui, B . Wang, K. Ball, and L. Freitag, "An underwater sensor network testbed: Design, implementation, and measurement," in Proc. WUWNet, pp. 65-72, Montreal, Canada, Sept. 2007.
  8. A. Goodney, Y. H. Cho, J. Heidemann, and J. Wroclawski, "An underwater communication and sensing testbed in marina del rey," in Proc. ACM WUWNet, Wood Hole, USA, Sept. 2010.
  9. B. Chen and D. Pompili, "A testbed for performance evaluation of underwater vehicle team formation and steering algorithms," in Proc. IEEE SECON, pp. 1-4, Boston, USA, Jun. 2010.
  10. J. Alves, J. Potter, G. Zappa, P. Guerrini, and R. Been, "A testbed for collaborative development of underwater communications and networking," in Proc. IEEE MILCOM, pp. 1-8, Orlando, USA, Oct. 2012.
  11. C. Petrioli and R. Petroccia, "SUNSET: Simulation, emulation and reallife testing of underwater wireless sensor networks," in Proc. IEEE UComms, pp. 1-12, Sestri Levante, Italy, Sept. 2012.
  12. J. Rice, B. Creber, C. Fletcher, P. Baxley, K. Rogers, K. McDonald, D. Rees, M. Wolf, S. Merriam, R. Mehio, J. Proakis, K. Scussel, D. Porta, J. Baker, J. Hardiman, and D. Green, "Evolution of seaweb underwater acoustic networking," in Proc. OCEANS 2000 MTS/IEEE, vol. 3, pp. 2007-2017, Providence, USA, Sept. 2000.
  13. J. Rice and D. Green, "Underwater acoustic communications and networks for the US Navy's seaweb program," in Proc. SENSORCOMM '08, pp. 715-722, Cap Esterel, France, Aug. 2008.
  14. G. Toso, R. Masiero, P. Casari, O. Kebkal, M. Komar, and M. Zorzi, "Field experiments for dynamic source routing: S2c evologics modems run the SUN protocol using the desert underwater libraries," in Proc MTS/IEEE OCEANS, pp. 1-10, Hampton Roads, USA, Oct. 2012.
  15. A. Caiti, V. Calabro, L. Fusini, A. Munafo, K. Grythe, J. M. Hovem, and A. L. T. A. Reinen, "Underwater acoustic network performance: Results from the UAN11 sea trial," in Proc. MTS/IEEE OCEANS, pp. 1-8, Hampton Roads, USA, Oct. 2012.
  16. Benthos Modem Brochure, Retrieved Dec. 9, 2013, from http://www.benthos.com/_doc/main/Brochures_Datasheets/Modems_brochure_201 3_lo_4_pg_1.pdf