A comparison of filter design structures for multi-channel acoustic communication systems.
The application of inverse filter designs as a means of providing improved communication performance in acoustic environments is investigated. Tikhonov regularized inverse filters of channel transfer functions calculated in the frequency domain are used as a means of obtaining multi-channel filters. Three classifications of inverse filter structures have been considered using time-domain simulations. The performance of Tikhonov regularized inverse filters designed according to each of these classifications is compared with each other and against a filter design developed by Stojanovic [Stojanovic, M. (2005). "Retrofocusing techniques for high rate acoustic communications," J. Acoust. Soc. Am. 117, 1173-1185]. It is shown that the filter design developed by Stojanovic requires less regularization and outperforms the Tikhonov regularized inverse filter designs when communicating over a single channel. While the filter developed by Stojanovic is designed to use multiple transmitters to transmit to a single receiver, the filter was implemented in a multi-channel system and proposed to have a focusing similar to that obtained using time-reversal. It was found that for the scenario used in the simulation, the Tikhonov regularized inverse design for full multi-channel inversion achieved better focusing than the design by Stojanovic, where simulation results show 20 dB less cross-talk at the expense of around 2 dB loss in signal strength.
Dumuid
Pierre M
PM
ANVC Group, School of Mechanical Engineering, The University of Adelaide, South Australia. pierre.dumuid@adelaide.edu.au
Cazzolato
Ben S
BS
Zander
Anthony C
AC
D000162:Acoustics; D003142:Communication; D004867:Equipment Design; D006801:Humans; D015233:Models, Statistical; D011601:Psychophysics / Q000295:instrumentation; D013997:Time Factors