Title :
Underwater acoustic communication system of AUV
Author :
Wei-Qing, Zhu ; Chang-Hong, Wang ; Feng, Pan ; Min, Zhu ; Rui, Wang ; Xiang-Jun, Zhang ; Yong-Mei, Dai
Author_Institution :
Inst. of Acoust., Acad. Sinica, Beijing, China
fDate :
28 Sep-1 Oct 1998
Abstract :
The underwater acoustic communication system (UACS) is an important part of an AUV. We developed an underwater acoustic communication system for a AUV: IASS-1, which is based on both MFSK and MPSK. Generally a AUV sends a large amount of data to the host vessel, and MPSK modulation is adopted. The receiver on the host vessel adopts space diversity (SD), a decision feedback equalizer (DFE), and fast self-optimized LMS phase estimator (FOLMSPE) techniques jointly. The fast self-optimized LMS (FOLMS) algorithm is implemented in the DFE. A short vertical hydrophone array is suspended or towed on the host vessel for signal reception. The separation between each hydrophone is far larger than the wavelength. The MFSK modulation and convolution code are adopted when the host vessel sends a message to the AUV. The receiver on AUV adopts the Viterbi algorithm. This well-known mechanism, using MFSK and convolution code, performs well when the transmission rate is low. Compared with MPSK modulation, it has the advantage of being very resistant to the most difficult multipath propagation, and is less sensitive to the vessel scattered wave. IAAS-1 was tested in a lake and was successfully operated at ranges over 100-4000 m (constrained by the test area). The symbol rate for QPSK is 2.5 ks/s and 5.0 ks/s. The bit error rate (BER) is between 10-4 and 10-5
Keywords :
acoustic receivers; acoustic transducer arrays; convolutional codes; decision feedback equalisers; diversity reception; frequency shift keying; hydrophones; least mean squares methods; modulation coding; multipath channels; phase estimation; quadrature phase shift keying; remotely operated vehicles; underwater acoustic communication; underwater vehicles; 100 to 4000 m; AUV; DFE; FOLMS algorithm; FOLMSPE; IASS-1; MFSK; MPSK; UACS; Viterbi algorithm; autonomous underwater vehicles; bit error rate; convolution code; decision feedback equalizer; fast self-optimized LMS algorithm; fast self-optimized LMS phase estimator; modulation; multipath propagation; receiver; short vertical hydrophone array; signal reception; space diversity; symbol rate; transmission rate; underwater acoustic communication system; vessel scattered wave; Bit error rate; Convolution; Decision feedback equalizers; Least squares approximation; Modulation coding; Phase estimation; Sonar equipment; Testing; Underwater acoustics; Viterbi algorithm;
Conference_Titel :
OCEANS '98 Conference Proceedings
Conference_Location :
Nice
Print_ISBN :
0-7803-5045-6
DOI :
10.1109/OCEANS.1998.725793