Influence of the clock of the encoding pulses in hydroacoustic transmission of binary numbers

  • 1 Institute of Metal Science, Equipment and Technologies, with Hydro- and Aerodynamics Centre “Acad. A. Balevski”, Bulgarian Academy of Sciences, Sofia, Bulgaria


Hydroacoustic waves are used to experimentally transmit binary numbers underwater. The numbers are first encoded into pulse sequences, according to the encoding scheme: two consecutive short pulses for a digit zero and two consecutive long pulses for a digit one. A clock period determines the timing of the encoding pulses. The influence of the clock period duration on the number of correctly transmitted binary numbers is tested in 30m deep coastal seawater, at a 1500m distance. The performance is compared at three different periods of the clock: 10ms, 20ms and 40ms. Increasing the clock period of the encoding pulses leads to an increase in the number of correct transmissions. At the longest tested clock period of 40ms all the transmissions of binary numbers are successful. Certainty of correct transmission increases at the longer clock periods of the encoding pulses due to attenuated interference from reflected signals.



  1. L. Liu, S. Zhou, J.-H. Cui, Prospects and Problems of Wireless Communication for Underwater Sensor Networks, Wireless Communications and Mobile Computing, 8 (8), 977-994 (2008)
  2. J. Partan, A Survey of Practical Issues in Underwater Networks, Computer Science Department Faculty Publication Series, 133 (2006)
  3. M. Stojanovic, J. Preisig, Underwater Acoustic Communication Channels: Propagation Models and Statistical Characterization, IEEE Communications Magazine, 47 (1), 84-89 (2009)
  4. I. Ivanov, R. Rainov, Ch. Ormanov, B. Monev, S. Vodenicharov, S. Kolev, Мarine Mines Control System, Patent 99649/15.01.1997. (not publicly available)
  5. 6.pdf
  6. A. Bensky, Radio Communication Basics, Wireless Security: Know It All, 77- 136 (2008)
  7. Н. Георгиев, А. Коларов, В. Пехливански, Тенденции в развитието на безжичните подводни комуникации, Инженерни науки, год. LVI, 2, 19-30 (2019)

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