Doppler Frequency Estimation for Time-Varying Underwater Acoustic Communication Channel

Tracking of Rapidly Time-Varying Sparse Underwater Acoustic Communication Channels

Characterization of Long-Range Time-Varying Underwater Acoustic Communication Channels

Underwater acoustic communication over Doppler spread channels

by Trym H. Eggen Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 1997 This work is concerned with coherent communication by means of acoustic signals over underwater communication channels. The estimated scattering functions of real data ranging from the Arc...

Doppler Effect Compensation for Cyclic-prefix-free Ofdm Signals in Fast-varying Underwater Acoustic Channel

In this paper, we propose a receiver of OFDM signals in fast-varying multipath underwater acoustic channels with Doppler spread covering several subcarrier intervals. The OFDM signals are cyclicprefix-free and the transmitted and pilot data are superimposed. The data symbols are encoded across subcarriers to exploit the frequency diversity. The receiver employs three stages for compensating the...

Underwater Acoustic Channel Estimation and Analysis

This paper analyzes statistical characteristics of underwater acoustic channels using experimental measurements. Channel impulse responses (CIRs) are estimated in the time domain using a least square method with sliding windows applied to received data. The probability density functions (PDF) of the real part, imaginary part, magnitude, and phase of the CIR are estimated, and the two-sample Kol...