WCSE 2015
ISBN: 978-981-09-5471-0 DOI: 10.18178/wcse.2015.04.091

Turbo Equalizer with Doppler Compensation for Underwater Channel: Experimental Results

Gun-Woong Park, Ji-Won Jung

Abstract— In this paper an acoustic underwater communication link is presented. The channel has severe inter symbol interference, we presented an iterative turbo equalization to cope with inter symbol interference induced by reflection of sea-level and sea-bottom for underwater sensor communication channel. Iterative turbo equalizer consists of inner codes and outer codes, we employ decision feedback equalizer as an outer codes and turbo codes as an inner codes. Equalizer and decoder are connected through the interleaving and de-interleaving that update each other's information repeatedly. At the receiver side, we resort to powerful turbo equalization algorithms that iteratively exchange probabilistic information between inner decoder and outer decoder, thereby reducing the error rates significantly. Very important for a successful decoding is the Doppler compensation, which also is discussed. The raw data rate is 1 [Kbps] but after reduction for the error correction coding the net bit rate is 2[kbit/s], a reliable communication is shown up to the distance of 350[m].

Index Terms— Underwater acoustic communications, Inter symbol interference, Turbo equalization, Doppler estimation, Decision Feedback Equalizer.

Gun-Woong Park, Ji-Won Jung
Department of Radio Communication Engineering,Korea Maritime and Ocean University, KOREA


Cite: Gun-Woong Park, Ji-Won Jung, "Turbo Equalizer with Doppler Compensation for Underwater Channel: Experimental Results," 2015 The 5th International Workshop on Computer Science and Engineering-Information Processing and Control Engineering (WCSE 2015-IPCE), pp. 547-552, Moscow, Russia, April 15-17, 2015.