title: Time reversal communication in a time-varying sparse channel.
abstract: Recently time reversal (TR) communications has been extended to time-varying channels. The basic idea is to implement it on a block-by-block basis such that within each block the channel remains time-invariant and subsequently is updated using detected symbols (decision-directed mode). Using experimental data (12-20 kHz) collected in shallow water, this letter investigates three different block-based TR approaches: (1) without explicit phase tracking, (2) with phase tracking, and (3) exploiting channel sparsity. The TR approaches then are compared to a conventional adaptive multichannel equalizer. It is found that approach (3) generally provides the best performance and robustness.
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0238, USA. hcsong@ucsd.edu
authors.forename: H C
authors.initials: HC
authors.lastname: Song
mesh_terms: D000162:Acoustics; D000465:Algorithms; D016018:Least-Squares Analysis; D008962:Models, Theoretical; D009038:Motion; D012815:Signal Processing, Computer-Assisted; D013016:Sound; D013018:Sound Spectrography; D013997:Time Factors; D014867:Water
chemical_list: D014867:Water