Multichannel time-reversal processing for acoustic communications in a highly reverberant environment

• Published in: The Journal of the Acoustical Society of America 2005-10, Vol.118 (4), p.2339-2354
• Main Authors: Candy, James V., Poggio, Andrew J., Chambers, David H., Guidry, Brian L., Robbins, Christopher L., Kent, Claudia A.
• Format: Article
• Language: English
• Subjects: Acoustic signal processing; Acoustics; Communication; Environment; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Humans; Noise - adverse effects; Physics; Time Factors
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.2011167

The development of time-reversal (T/R) communication systems is a recent signal processing research area dominated by applying T/R techniques to communicate in hostile environments. The fundamental concept is based on time-reversing the impulse response or Green's function characterizing the uncertain communications channel to mitigate deleterious dispersion and multipath effects. In this paper, we extend point-to-point to array-to-point communications by first establishing the basic theory to define and solve the underlying multichannel communications problem and then developing various realizations of the resulting T/R receivers. We show that not only do these receivers perform well in a hostile environment, but they also can be implemented with a " 1 bit " analog-to-digital converter design structure. We validate these results by performing proof-of-principle acoustic communications experiments in air. It is shown that the resulting T/R receivers are capable of extracting the transmitted coded sequence from noisy microphone array measurements with zero-bit error.