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Updated: May 21, 2026

Continuous-Wave Propagation Channel-Sounding Measurement System - Testing, Verification, and Measurements
Published on: June 25, 2021
Parameterizing both path amplitude and delay variations of underwater acoustic channels for block decoding of
Xiaoka Xu1, Zhaohui Wang, Shengli Zhou
1Department of Electrical and Computer Engineering, University of Connecticut, 371 Fairfield Road, Unit 2157, Storrs, Connecticut 06269, USA.
Abstract:
There are no commonly-agreed mathematical models for the input-output relationship of underwater acoustic channels. For each path in a time-varying multipath channel within a short period of time (e.g., one short data block), this paper proposes to use one polynomial to approximate the amplitude variation and another polynomial up to the first order to approximate the delay variation within a block duration. Under such a channel parameterization, the discrete-time channel input- output relationship tailored to zero-padded orthogonal-frequency-division-multiplexing (OFDM) transmissions is then derived, based on which an OFDM receiver is validated using experimental data collected during the 2008 Surface Processes and Acoustic Communications Experiment. For channels with a short coherence time, the numerical results show that incorporating both the amplitude and delay variations improves the system performance.
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