Measurement Science and Technology · 2001 · 21 citations · 6 references
EngineeringMarine EngineeringOcean EngineeringAcousticsOcean AcousticsUnderwater AcousticsDigital Signal ProcessingDoppler UltrasonographyDoppler Velocity MeasurementRadar Signal ProcessingSonar SystemsUltrasonicsDoppler EstimationDoppler Shift AnalysisDoppler Shift MeasurementsFourier TransformSignal ClassificationSignal-to-noise RatioUnderwater Acoustic Signal ProcessingVelocity
In order to estimate ship velocity, we have applied the multiple signal classification (MUSIC) method to one-pulse burst-echo Doppler sonar data. The MUSIC method enabled us to estimate the Doppler frequency shift precisely under a low-signal-to-noise ratio (SNR) situation even from a one-pulse burst-echo signal with small data points. In simulation experiments, a signal frequency component of f = 16 Hz could be extracted from N = 128 data-point data under a 40% Gaussian-distributed additive noise with a sampling frequency fs = 2048 Hz. From actual one-pulse burst-echo signal data of N = 128 points, a Doppler frequency shift of Δf = 1.45 kHz, corresponding to a ship velocity 1.76 knots, was clearly detected, the frequency resolution of which was almost impossible to attain by the conventional Fourier transform (FFT) method. We found that the MUSIC method was useful especially for estimating the ship velocity at a very low speed.
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