A high-precision shipborne strapdown gravimetry method adaptively robust to global navigation satellite system signal anomalies

Abstract

The signal anomalies of global navigation satellite system (GNSS) are the key factors for the performance of shipborne strapdown gravimetry. In order to obtain reliable gravity information in real-time and at low operating cost in the conditions of signal outages or interference, we show a high-precision strapdown gravimetry method adaptively robust to GNSS signal anomalies. During signal outages, the method can reliably output gravity information by the strapdown inertial navigation system/pseudo log (SINS/PL) integration based on covariance matching adaptive Kalman filter. During interference or normal signal, the method uses the SINS/GNSS integration based on linear Huber-M estimation robust Kalman filter to perform gravimetry. The marine shipborne experiments show that, under the conditions of GNSS signal outages and interference scenarios, the overall accuracy of the method reaches 0.771mGal. By adaptively adjusting the measurement modes and advanced filters, the method can effectively handle GNSS signal anomalies. Compared to existing methods, it has superior comprehensive performance, such as higher computational efficiency and robustness.