A6airaciThe majority of model-based techniquen proposed to date for solving the multiple source direction-ofarrival (DOA) estimation problem operate under the assumption that the wavefronts impinging on the array are planar. However, when nourcea are located close to the array (i.e., in the near-field), the inherent curvature of the wavefront is no longer negligible. In this paper, we propose t...

Based upon the sparse array composed of cluster SAR satellites, this paper analyzes the space-time and space-frequency characteristic of the received signal in detail, and proposes an algorithm for the moving targets detection and imaging based on array signal processing and Wigner-Ville Distribution (WVD). The results of theoretical analysis and simulation show that the cluster SAR system can ...

In order to achieve the highly efficient and accurate identification of fracture modes including tension or shear fractures during rock failure, an intelligent method based on Wigner-Ville distribution (WVD) spectrogram features acoustic emission (AE) signals was proposed. This mainly constructed by following steps: Firstly, AE hits corre-sponding were obtained through conducting Brazilian disc...

[1] Magnetospheric ultra-low-frequency (ULF) waves (f = 1 mHz to 1 Hz) exhibit highly time-dependent characteristics due to the dynamic properties of these waves and, for observations in space, the spacecraft motion. These time-dependent features may not be properly resolved by conventional Fourier techniques. In this study we examine how the Wigner-Ville distribution (WVD) can be used to analy...

For a non-stationary seismic signal, time–frequency analysis methods often include time window function that serves as weighting and by which the signal is multiplied to form segment. The has highest coefficient for central sample of rest segment, there no adequate representation in frequency spectrum. Here, I propose use multiple orthogonal functions properly represent local spectral property ...