Joint Source Enumeration and Direction Finding without Eigendecomposition for Satellite Navigation Receiver

Fast and accurate source number detection and direction of arrival (DOA) estimation are of considerable interest in satellite navigation receiver with antenna arrays. Normally, the number of sources is assumed to be known perfectly, however, is unknown in practice. This paper develops a computationally efficient joint estimation method of satellite signal number and DOA by designing a shared multistage Wiener filter (MSWF). First, considering complicated interference, such as broadband interference, the spatial-temporal signal processing model is adopted to increase the degree of freedom of antenna array. Then, using the principle of orthogonal projection and signal subspace reconstruction of MSWF, the enhanced Gerschgorin radii and satellite signal subspace without eigenvalue decomposition (EVD) are reformulated, respectively. At last, using the so-obtained signal number, both the DOAs and the frequencies of satellite signal and interference can be accurately estimated by multiple signal classification (MUSIC) in the spatial-temporal joint domain. Numerical results are presented to demonstrate the performance of the method.