Print Email Facebook Twitter Multi-beam echo-sounder bathymetric measurements Title Multi-beam echo-sounder bathymetric measurements: Implications of using frequency modulated pulses Author Mohammadloo, Tannaz H. (TU Delft Aircraft Noise and Climate Effects) Snellen, M. (TU Delft Aircraft Noise and Climate Effects) Simons, D.G. (TU Delft Aircraft Noise and Climate Effects) Date 2018 Abstract In this contribution bathymetric uncertainties induced by the use of frequency modulated (FM) signals for multi-beam-echo-sounder (MBES) measurements are quantified and their relevance for MBES bathymetric uncertainty predictions is assessed. When switching to FM, the quality of depth measurements can get deteriorated due to the Doppler effect and baseline decorrelation. The uncertainty due to the former is divided into second-order (imperfectness of the Doppler-range correction) and first-order (effect on beamsteering) effects. The latter also holds for continuous wave (CW) signals. Here, situations of relevance for measurements in the continental shelf and ship dynamics associated to rough and calm sea-states are considered, and the vertical uncertainty induced by the above sources is quantified. The influence of the Doppler effect depends on the sea state, but is found to potentially have a significant contribution to the MBES error budget for both FM and CW [nearly 82% (rough) and 68% (calm) of the total uncertainty]. The effect of baseline decorrelation depends on the actual pulse shape. For the specifications investigated, vertical uncertainties induced by this source are predicted to be larger for FM than that of CW. This is confirmed by a comparison between the modelled and measured effect on depth uncertainties when switching to FM. To reference this document use: http://resolver.tudelft.nl/uuid:caa3cce0-bdc0-4eb1-bc3d-c910748acfe1 DOI https://doi.org/10.1121/1.5050816 Embargo date 2019-04-30 ISSN 0001-4966 Source The Journal of the Acoustical Society of America, 144 (2), 842-860 Part of collection Institutional Repository Document type journal article Rights © 2018 Tannaz H. Mohammadloo, M. Snellen, D.G. Simons Files PDF 1.5050816.pdf 4.27 MB Close viewer /islandora/object/uuid:caa3cce0-bdc0-4eb1-bc3d-c910748acfe1/datastream/OBJ/view