|Title||An overview of underwater time-reversal communication|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Journal||Ieee Journal of Oceanic Engineering|
|Type of Article||Article|
|Keywords||acoustic communications l; adaptive equalization; Adaptive multichannel equalization; communication; crosstalk; decision-feedback equalizer; interference cancellation; MIMO/multiuser; multiuser communications; passive-phase-conjugation; performance analysis; retrofocusing techniques; shallow-water; synthetic-aperture communications; time reversal (TR); underwater acoustic (UWA)|
Time reversal (TR) exploits spatial diversity to achieve spatial and temporal focusing in complex environments. Over the last decade, the TR concept has been applied successfully to phase-coherent acoustic communications in time-varying multipath ocean environments, as an alternative to conventional adaptive multichannel equalization. Temporal focusing ( pulse compression) mitigates the intersymbol interference (ISI) and subsequent single-channel equalization removes the residual ISI, thus providing nearly optimal performance in theory. The spatial focusing capability facilitates multiuser or multiple-input-multiple- output ( MIMO) communications without explicit use of time, frequency, or code division multiplexing, while an adaptive TR approach can reduce further the crosstalk among users or multiple transmitters. TR communications can be extended easily to time-varying channels using a block-based approach with channel updates. This paper provides an overview of TR communications in both shallow and deep water and recent advances including bidirectional equalization, multiuser communications with mobile users, and communication with a glider serving as a mobile gateway.
|Short Title||IEEE J. Ocean. Eng.|