Abstract
Multibeam echosounding technique is used to provide sea-floor mapping with relatively high-quality level and requires an accurate positioning and attitude system. Integration of Global Navigation Satellite System (GNSS) and inertial navigation system (INS) is widely used for positioning and attitude control and is carried out using an inertial unit integrated with GNSS solution to provide the required accuracy. Recently, the Kingdom of Saudi Arabia Continuously Operating Reference Station (KSACORS) network GNSS stations were developed by the Saudi Geodetic Commission for Survey (GCS) to maintain an accurate GNSS positioning solution for governmental and private sectors within Saudi Arabia coverage area. This paper investigates the performance of the KSACORS-based network GNSS-INS integration for Saudi coastal hydrographic surveys and also investigates whether the archived accuracy fulfill International Hydrographic Organization (IHO) standards for all survey orders. To meet this objective, the KSACORS-based network real-time-kinematic (NRTK) and network post-processed kinematic (NPPK) solutions are integrated with INS solution. The implementation of the KSACORS-based NRTK and NPPK GNSS-INS integration methods shows that centimeters and arc-minutes level of accuracies for position and attitude solutions, respectively, can be successfully achieved throughout onshore hydrographic surveys. Also, it is shown that the KSACORS-based NRTK GNSS-INS and NPPK GNSS-INS integration systems fulfill IHO standards for all survey orders and can be employed for Saudi coastal multibeam echosounding surveys. The significant contribution of the paper is that it implemented the performance of KSACORS-based NRTK GNSS-INS and NPPK GNSS-INS integration systems for hydrographic surveying application and validated their accuracies against IHO standards.