Strapdown inertial navigation heave measurement method based on improved singular spectrum analysis

The invention provides a strapdown inertial navigation heave measurement method based on improved singular spectrum analysis, which comprises the following steps of: performing singular value decomposition on a sky-direction acceleration time sequence by using conventional singular spectrum analysis to obtain an acceleration initialization singular value matrix and an initialization feature vector matrix; and performing grouping reconstruction according to the singular value features to obtain accelerated speed with noise filtered out, and performing integration to obtain speed. SVD decomposition is carried out on the speed time sequence, a speed initialization singular value matrix and an initialization feature vector matrix are obtained, and initialization is completed. Recursive updating is carried out, real-time updating is carried out through sky-direction acceleration driving data, an acceleration singular value matrix and a feature vector matrix at the current moment are obtained, noise-filtered accele