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Enhanced Data Transmission Rate of XCTD Profiler Based on OFDM

  • Hongzhi Li
  • Sai Zhang
  • Xiaocong Qin
  • Xiaoyang Zhang
  • Yu ZhengEmail author
Article
  • 4 Downloads

Abstract

An expendable conductivity-temperature-depth profiler (XCTD) is one of the most important instruments used to obtain hydrological data, such as temperature and conductivity, and detect ocean depth in a large area. However, the XCTD channel provides poor time-varying performance, narrowband, and low signal-to-noise ratio (SNR), which severely restricts the data transmission rate. In contrast to conventional single-carrier modulation techniques, such as amplitude-shift keying and differential phase-shift keying, this article provides a new method, based on orthogonal frequency division multiplexing (OFDM) to enhance the data transmission rate of deep-sea abandoned profilers. We apply the OFDM to enhance the SNR of the XCTD, which is achieved by reducing the data transmission rate of each sub-channel. Moreover, the bandwidth utilization may be improved by increasing the number of subcarriers in a given bandwidth, which enhances the data transmission rate. Based on analysis of the XCTD channel model, OFDM with different parameters such as constellation mapping, number of subcarriers, subcarrier spacing, signal period and cyclic prefix are achieved. To verify the effectiveness of the OFDM, this study investigates the influence of different parameters on the data transmission rate at different noise levels, i.e., −20 dB and −40 dB.

Key words

XCTD OFDM subcarrier bandwidth utilization data transmission rate 

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Notes

Acknowledgements

This study was supported by the National Key Research and Development Program of China (No. 2016 YFC1400400), and the Marine Economic Innovation and Development Demonstration Project in Binhai New Area (No. 1723434C4114194).

References

  1. Alexander, S., and Darren, W., 2000. XBT/XCTD Standard test procedures for reliability and performance tests of expendable probes at sea. 3rd Session of JCOMM Ship-of-Opportunity Implementation Panel. La Jolla, California, 1–8.Google Scholar
  2. Baron, G., and Mendoza, D., 1984. A System for calibration of expendable conductivity, temperature, and depth (XCTD) probes. IEEE Oceans Conference. Washington, D. C., 210–213, DOI: 10.1109/OCEANS.1984.1152331.Google Scholar
  3. Chen, H. S., van den Boom, H. P. A., and Koonen, A. M. J., 2010. OFDM MMF optical communication transmission system based on mode group division multiplexing. Proceedings 15th Annual Symposium of the IEEE Photonics Benelux Chapter. Delft, the Netherlands, 97–100.Google Scholar
  4. Chen, L., Jia, Z. C., Li, Y. J., Zhang, L. Y., and Zhang, Y., 2009. Development of data transmission system of expendable CTD profiling system. Ocean Technology, 28 (3): 26–29 (in Chinese with English abstract).Google Scholar
  5. Chuang, J., and Sollenberger, N., 1999. Wideband wireless data access based on OFDM and dynamic packet assignment. Wireless Communications and Networking Conference. New Orleans, LA, 757–761, DOI: 10.1109/WCNC.1999.796749.Google Scholar
  6. Jia, Z. C., Yu, X. S., Ni, J. J., Li, Y. J., and Chen, L., 2010. Design and realization of data transmission circuit for XCTD profiler. Ocean Technology, 29 (2): 1–4 (in Chinese with English abstract).Google Scholar
  7. Johnson, G. C., 1995. Revised XCTD fall-rate equation coefficients from CTD data. Journal of Atmospheric and Oceanic Technology, 12 (6): 1367–1373.CrossRefGoogle Scholar
  8. Kizu, S., Onishi, H., Suga, T., Hanawa, K., Watanabe, T., and Iwamiya, H., 2008. Evaluation of the fall rates of the present and developmental XCTDs. Deep Sea Research Part I: Oceanographic Research Papers, 55 (4): 571–586, DOI: 10.1016/j.dsr.2007.12.011.CrossRefGoogle Scholar
  9. Li, Q. W., Zheng, Y., Tian, L., Song, G. M., Shang, Y. S., Jin, X. Y., and Wang, X. R., 2017. Analysis of Signal error rate of time-varying channel effects on ASK band transmission of deep-sea abandoned profiler measuring instrument. International Conference on Communication and Electronic Information Engineering. Guangzhou, 540–546, DOI: 10.299/ceie-16.2017.69.Google Scholar
  10. Miyoshi, K., 2001. Preliminary design of OFDM and CDMA acoustic communication system. IEEE Oceans Conference. Honolulu, 2216–2219, DOI: 10.1109/OCEANS.2001.968342.Google Scholar
  11. Nee, R. V., and Prasad, R., 2000. OFDM for Wireless Multimedia Communications. Artech House Publishers, Norwood, 1–270.Google Scholar
  12. Qaddour, J., Leonard, D., Matalgah, M. M., and Guizani, M., 2003. Beyond 3G: Uplink capacity estimation for wireless spread-spectrum orthogonal frequency division multiplexing (SS-OFDM). Global Telecommunications Conference. San Francisco, 4139–4141, DOI: 10.1109/GLOCOM.2003.1259006.Google Scholar
  13. Stuber, G. L., Barry, J. R., Mclaughlin, S. W., Li, Y., Ingram, M. A., and Pratt, T. G., 2004. Broadband MIMO-OFDM wireless communications. Proceedings of the IEEE, 92 (2): 271–294, DOI: 10.1109/jproc.2003.821912.CrossRefGoogle Scholar
  14. Uehara, H., Kizu, S., Hanawa, K., Yoshikawa, Y., and Roemmich, D., 2008. Estimation of heat and freshwater transports in the North Pacific using high-resolution expendable bathythermograph data. Journal of Geophysical Research Atmospheres, 113 (2): 503–504, DOI: 10.1029/2007JC004165.Google Scholar
  15. Wijffels, S. E., Willis, J., Domingues, C. M., Barker, P. M., White, N. J., Gronell, A., Ridgway, K., and Church, J. A., 2008. Changing expendable bathythermograph fall rates and their impact on estimates of thermosteric sea level rise. Journal of Climate, 21 (21): 5657–5672, DOI: 10.1175/2008jcli22 90.1.CrossRefGoogle Scholar
  16. Zhao, X., Zheng, Y., Jing, L. I., Wang, J. H., Li, H. Z., and Liu, N., 2014. Effects of distributed capacitance among XCTD profiler transmission wire on equivalent inductance. Instrument Technique and Sensor, 43 (7): 54–57 (in Chinese with English abstract).Google Scholar
  17. Zheng, Y., Fu, X. H., Zhao, X., Gao, Y., Fang, J., Wang, J. H., Li, H. Z., and Liu, N., 2014. The method of improving the phase stability of time-varying channels of vessel-mounted XCTD profilers. Journal of Ocean Technology, 33 (3): 12–17 (in Chinese with English abstract).Google Scholar
  18. Zheng, Y., Gao, Y., Fang, J., Song, G. M., Shang, Y. S., and Li, H. Z., 2015. The research methods of a time-varying channel model of the XCTD profiler. Journal of Geophysics and Engineering, 12 (5): 849–856, DOI: 10.1088/1742-2132/12/5/849.CrossRefGoogle Scholar
  19. Zheng, Y., Song, G. M., Shang, Y. S., Jin, X. Y., Wang, X. R., Tian, L., and Liu, J. W., 2017. Analysis of the DPSK transmission carrier frequency of time-varying channel model of XCTD profiler. International Conference on Communication and Electronic Information Engineering. Guangzhou, 534–539.Google Scholar
  20. Zheng, Y., Song, G. M., Shang, Y. S., Li. H. Z., Zhang, X. W., Tian, L., and Li, Q. W., 2018. Research on improving transmission reliability of deep sea disposal profiler by RS-CC concatenated code. Periodical of Ocean University of China, 48 (9): 140–146 (in Chinese with English abstract).Google Scholar
  21. Zheng, Y., Zhao, X., Li, J., Wang, J. H., Li, H. Z., and Liu, N., 2013. Dynamic analysis of XCTD profiler signal transmission. Ocean Technology, 32 (4): 11–14 (in Chinese with English abstract).Google Scholar
  22. Zheng, Y., Zhao, X., Li, J., Fu, X. H., Wang, J. H., Li, H. Z., and Liu, N., 2014. Analysis of time-varying channel effects on transmission performance of deep-sea abandoned measuring instrument. Acta Physica Sinica, 63 (4): 69–76, DOI: 10.7498/ aps.63.040507.Google Scholar

Copyright information

© Ocean University of China, Science Press and Springer-Verlag GmbH Germany 2019

Authors and Affiliations

  • Hongzhi Li
    • 1
  • Sai Zhang
    • 2
  • Xiaocong Qin
    • 2
  • Xiaoyang Zhang
    • 2
  • Yu Zheng
    • 2
    Email author
  1. 1.National Ocean Technology CenterTianjinChina
  2. 2.School of Electronics and Information EngineeringTianjin Polytechnic UniversityTianjinChina

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