Fig. 1. QPSK system, (a) modulation system, (b) demo-dulation system, and (c) its scatter plot.
Fig. 2. Raised cosine filter according to the roll-offf actor, (a) time signal and (b) frequency response.
Fig. 3. Experimental configuration.
Fig. 4. Experimental configuration, (a) impulse response at 100 m, (b) impulse response at 400 m.
Fig. 5. Results of simulations according to roll-off factor, (a) Rcos (0.0), (b) Rcos (0.5), (c) Rcos (1.0), and (d) Rect+Rcos (0.5).
Table 1. Simulation and experimental parameters.
Table 2. Simulation results.
참고문헌
- T. C. Yang, "Properties of underwater acoustic communication channels in shallow water," J. Acoust. Soc. Am. 131, 129-145 (2012). https://doi.org/10.1121/1.3664053
- W. B. Yang and T. C. Yang, "High-frequency channel chara- cterization for M-ary frequency-shift-keying underwater acoustic communications," J. Acoust. Soc. Am. 120, 2615-2626 (2006). https://doi.org/10.1121/1.2346133
- T. B. Aik, Q. S. Sen, and Z. Nan, "Characterization of multipath acoustic channels in very shallow waters for communications," Proc. of OCEANS'06 Asia-Pacific Conference, 1-8 (2007).
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- J. R. Yoon, K. C. Park, J. Park, and J. Park, "Performance comparison between packet and continuous data transmission using two adaptive equalizers in shallow water," Jpn. J. Appl. Phys. 50, 07HG05 (2015).
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- Raised Cosine Filtering, https://kr.mathworks.com/help/comm/examples/raised-cosine-filtering.html.
- T. S. Rappaport, Wireless Communications: Principles and Practice, 2nd ed. (Prentice Hall, New Jersey, 2002), pp. 400.
- Window Function, https://kr.mathworks.com/help/dsp/ref/windowfunction.html?searchHighlight=window%20function&s_tid=doc_srchtitle.