Title :
Low Complexity OFDM Detector for Underwater Acoustic Channels
Author :
Stojanovic, Milica
Author_Institution :
Massachusetts Inst. of Technol., Cambridge, MA
Abstract :
An adaptive algorithm is proposed for OFDM signal detection on Doppler-distorted, time-varying multipath channels. The focus of the approach is on low complexity post-FFT signal processing. The receiver performs MMSE combining of signals received across an array, using adaptive channel estimation. Non-uniform Doppler compensation across subbands is performed using a single adaptively estimated parameter representing the Doppler rate. Algorithm performance is demonstrated on experimental data, transmitted through a shallow water channel over the distance of 2.5 km. QPSK modulation with a varying number of carriers is used in a 24 kHz acoustic bandwidth. Excellent performance is achieved with up to 1024 carriers, yielding an overall bit rate of 30 kbps
Keywords :
Doppler measurement; fast Fourier transforms; geophysical signal processing; signal detection; underwater sound; 24 kHz; Doppler compensation; Doppler distorsion; MMSE; OFDM signal detection; QPSK modulation; adaptive algorithm; adaptive channel estimation; experimental data; orthogonal frequency division multiplexing; post-FFT signal processing; shallow water channel; signals receiver; underwater acoustic channels; Acoustic signal detection; Acoustic signal processing; Adaptive algorithm; Detectors; Multipath channels; OFDM; Signal detection; Signal processing algorithms; Underwater acoustics; Underwater tracking;
Conference_Titel :
OCEANS 2006
Conference_Location :
Boston, MA
Print_ISBN :
1-4244-0114-3
Electronic_ISBN :
1-4244-0115-1
DOI :
10.1109/OCEANS.2006.307057
