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Underwater Acoustic Channel Estimation and Statistical Analysis from Experimental Data. Missouri University of Science and Technology Department of Electrical and Computer Engineering Student: Jesse Cross Advisor: Dr. Rosa Zheng. RESULTS
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Underwater Acoustic Channel Estimation and Statistical Analysis from Experimental Data Missouri University of Science and Technology Department of Electrical and Computer Engineering Student: Jesse Cross Advisor: Dr. Rosa Zheng • RESULTS • The CIR estimation plot shows how the CIR can change with time. • The autocorrelation function is a measure of how likely the next coefficient values are related to the current coefficient. • OBJECTIVES • Estimate the channel impulse response (CIR) of the acoustic underwater channel • Compare the PDF of the channel coefficients to known distributions • Analyze statistical properties such as the correlation, coherence time, and scattering function • BACKGROUND • Acoustic communication in shallow water is more complicated than in air radio communication due to the excessive pass loss, scattering, and time varying nature of the channel. Underwater Multipath • APPROACH • Experimental data from the Reschedule Acoustic Communications Experiment in March 2008 (RACE08) has been analyzed. • The CIR of the channel has been estimated many times using the sliding window least squares estimation technique in the time domain. • The coefficients of the CIRs calculated were used to plot the PDF of the underwater channel and to calculate the other statistical properties • FUTURE WORK • Data from other environments will be analyzed. • The knowledge gained from this experiment will be used to create a transceiver design that improves upon the speed of current transceivers. • DISCUSSION • Rayleigh PDF does not describe the experimental PDF • Channel coherence time is .12 seconds. Therefore, the channel is time invariant for about 470 symbols. • Doppler spread is very low in this channel since both the receivers and transmitters were fixed. • Observed Doppler spread is due to the movement of the channel medium, itself. Acknowledgements NSF grant ECCS-0846486 ONR grant N00014-10-1-0174 Intelligent Systems Center