Virtual Time Reversal in Underwater Acoustic Communications: results on the INTIFANTE'00 Sea Trial

S.M. Jesus and A. Silva sjesus@ualg.pt , asilva@ualg.pt
SiPLAB-FCT, Universidade do Algarve
Faro, Portugal

Comments: download pdf file .
Ref.: Forum Acusticum, Sevilla, Spain, 2002(invited).


Abstract : Underwater acoustic communications in waveguides is known to be prone to severe multipath, which strongly limitates practical transmission rates with actual equalization techniques. The virtual Time Reversal Mirror (vTRM) principle uses the actual response of the ocean waveguide to attempt to reduce the multipath structure which, under ideal conditions, allows for environment independent signal extraction. One of the known limiting factors is the time stability of the acoustic channel. This paper focuses essentially in two aspects: one, is to demonstrate the potential application of the vTRM approach to undo the severe intersymbol interference in a real variable geometry channel scenario and, the other, is the variability of detection performance with symbol rate and source - array distance. The results obtained on at-sea recorded data during the INTIFANTE'00 sea trial will be shown to support the expectations. 

ACKNOWLEDGMENT: this work was partially supported by projects INFANTE from FCT (Portugal) and LOCAPASS from FUP/MDN.