Assessing the Performance of the Phase Difference Bathymetric Sonar Depth Uncertainty Prediction Model

Realistic predictions of the contribution of the uncertainty sources affecting the quality of the bathymetric measurements prior to a survey is of importance. To this end, models predicting these contributions have been developed. The objective of the present paper is to assess the performance of the bathymetric uncertainty prediction model for...

Comparative assessment of measured and modelled aircraft noise around Amsterdam Airport Schiphol

The impressive growth of the aviation industry and the number of flights entail several environmental repercussions, such as increased aircraft noise emissions. With the worrying number of complaints from the communities around airports comes also the distrust in numerical models used for aircraft noise prediction. In this study, we compare...

Mapping the seabed and shallow subsurface with multi-frequency multibeam echosounders

Multi-frequency multibeam backscatter (BS) has indicated, in particular for fine sediments, the potential for increasing the discrimination between different seabed environments. Fine sediments are expected to have a varying signal penetration within the frequency range of modern multibeam echosounders (MBESs). Therefore, it is unknown to...

Assessing the performance of the multi-beam echo-sounder bathymetric uncertainty prediction model

Realistic predictions of the contribution of the various sources affecting the quality of the bathymetric measurements prior to a survey are of importance to ensure sufficient accuracy of the soundings. To this end, models predicting these contributions have been developed. The objective of the present paper is to assess the performance of...

Using Alternatives to Determine the Shallowest Depth for Bathymetric Charting: Case Study

Methods for gridding multibeam echo sounder (MBES) measurements to equidistant grids are proposed as alternatives to the shallowest measured depth, which is affected by outliers. The approaches considered use a combination of mean and standard deviation of soundings and the regression coefficient from the best fitted plane. These methods...

Assessment of reliability of multi-beam echo-sounder bathymetric uncertainty prediction models

Nowadays Multi-Beam Echo-Sounder (MBES) systems are used for obtaining information of the sea/river bed bathymetry and sediment composition. For the latter, use is usually made of the backscatter strength and depth derivatives, such as depth residuals. However, the depth derivatives are affected by the uncertainties inherent to the MBES varying...

Correcting Multibeam Echosounder Bathymetric Measurements for Errors Induced by Inaccurate Water Column Sound Speeds

In this contribution a method for correcting bathymetric measurements affected by inaccurate water column sound speed profiles (SSPs) is presented. The method exploits the redundancy in the multibeam echosounder measurements obtained from the overlap of adjacent swaths by minimizing the difference between depths along overlapping swaths. Two...

Comparing Modeled and Measured Bathymetric Uncertainties: Effect of Doppler and Baseline Decorrelation

Nowadays Multi-Beam Echo-Sounder (MBES) derived bathymetry is used for a large range of applications. However, these measurements are affected by the uncertainties inherent to the MBES. Since the development of the depth uncertainty prediction model, MBES systems have been improved noticeably. The present contribution addresses the importance of...

Minimum depth, mean depth or something in between?

Reliable information about the seafloor and river-bed bathymetry is of high interest for a large number of applications. A Multi-Beam echo sounder (MBES) system is able to produce high-resolution bathymetry data at relatively small cost. These measurements, providing a depth for each beam and every ping, are processed to obtain a more ordered...

Multi-beam echo-sounder bathymetric measurements: Implications of using frequency modulated pulses

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...

Assessing the repeatability of sediment classfication method and the limitations of using depth residuals

Knowing the morphology and sediment composition of the seabed is of high importance for various applications. In this contribution, the repeatability of acoustic seafloor classification (ASC) results obtained from MBES backscatter value is investigated. The unsupervised classification algorithm based on Principal Component Analysis has been...

An uncertainty assessment of the effect of using FM pulses on MBES depth measurements

The most recent generation multi-beam echosounders (MBES) allows to transmit Frequency Modulated (FM) signals, in addition to the more conventional Continuous Wave (CW) pulses. In this contribution, the effect of using these FM pulses for bathymetric measurements is investigated. Advantage of using FM signals is that measurements can be taken at...

Minimum depth, mean depth or something in between?