Extension of the area surveyed with the multibeam system in the Ria de Aveiro, Portugal, onboard the NEREIDE research vessel.

A Kongsberg EM 2040 C multibeam echo sounder transducer installed on the scientific vessel NEREIDE, was used to collect multibeam bathymetry data during graduation activities. This particular dataset was collected around the Ria de Aveiro, Portugal during January, 2021. The range of opening angles of the EM 2040 C multibeam varies between 60 and 65 degrees. The positioning system used was supported by the Real Time Kinematic (RTK) technique with the transmission of differential data in Ultra High Frequency (UHF) mode. The data is calibrated and corrected for the surface sound velocity. The processing of hydrographic data was performed using specific algorithms for hydrography - Combined Uncertainty and Bathymetric Estimator (CUBE). In its processing, data was referenced to the hydrographic Zero of Portugal and projected in the ETRS89-PTTM08 coordinate system.本数据集由安装于科研船“涅瑞伊德号（NEREIDE）”的康斯伯格（Kongsberg）EM 2040 C多波束测深仪（multibeam echo sounder）换能器（transducer），于毕业作业期间采集多波束测深数据所得。该数据集的采集区域为葡萄牙阿威罗湾（Ria de Aveiro）周边海域，采集时间为2021年1月。EM 2040 C多波束系统的开角范围为60°至65°。所用定位系统基于实时动态差分（Real Time Kinematic, RTK）技术，以超高频（Ultra High Frequency, UHF）模式传输差分数据。该数据已针对表层声速完成校准与改正。水文数据处理采用了面向水文测绘的专用算法——组合不确定性与测深估算器（Combined Uncertainty and Bathymetric Estimator, CUBE）。在数据处理流程中，所有数据均以葡萄牙水文零点为垂直基准，并投影至ETRS89-PTTM08坐标系。