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Time reversal communication over doubly spread channels.

Wen-Jun Zeng¹, Xue Jiang

¹Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong. cengwj06@mails.tsinghua.edu.cn

The Journal of the Acoustical Society of America

|November 14, 2012

Summary

This summary is machine-generated.

This study introduces novel time reversal receivers for underwater acoustic communications. These receivers effectively address both delay and Doppler spreads in time-varying channels, achieving precise temporal and frequency focusing.

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Area of Science:

Underwater acoustics
Signal processing
Wireless communication

Background:

Conventional time reversal effectively mitigates multipath delay dispersion but fails in time-varying channels with Doppler spread.
Existing adaptations of time reversal for time-variant channels require frequent updates and struggle with significant Doppler spread, limiting frequency focusing.

Purpose of the Study:

To propose two novel time reversal receivers for underwater acoustic communications in doubly spread channels.
To enable effective communication in challenging time-varying underwater acoustic environments.

Main Methods:

The proposed approach utilizes the channel spreading function for time-frequency channel matching, reducing the need for frequent channel updates.
A rake-like structure is employed to compensate for multiple Doppler shifts, overcoming the limitations of single Doppler shift correction.

Main Results:

The new receivers successfully counteract both delay and Doppler spreads simultaneously.
Achieved both temporal focusing (mitigating delay spread) and frequency focusing (mitigating Doppler spread).

Conclusions:

The proposed time reversal receivers offer a robust solution for underwater acoustic communications over doubly spread channels.
This method significantly enhances communication reliability and performance in dynamic underwater environments by achieving dual focusing.