A geometric approach to covariance matrix estimation and its applications to radar problems

A Aubry, A De Maio, L Pallotta - IEEE Transactions on Signal …, 2017 - ieeexplore.ieee.org
A new class of disturbance covariance matrix estimators for radar signal processing
applications is introduced following a geometric paradigm. Each estimator is associated with …

Gaussian distributions on Riemannian symmetric spaces: statistical learning with structured covariance matrices

S Said, H Hajri, L Bombrun… - IEEE Transactions on …, 2017 - ieeexplore.ieee.org
The Riemannian geometry of covariance matrices has been essential to several successful
applications, in computer vision, biomedical signal and image processing, and radar data …

The Riemannian Barzilai–Borwein method with nonmonotone line search and the matrix geometric mean computation

B Iannazzo, M Porcelli - IMA Journal of Numerical Analysis, 2018 - academic.oup.com
Abstract The Barzilai–Borwein (BB) method, an effective gradient descent method with
clever choice of the step length, is adapted from nonlinear optimization to Riemannian …

Computational aspects of the geometric mean of two matrices: a survey

DA Bini, B Iannazzo - Acta Scientiarum Mathematicarum, 2024 - Springer
Algorithms for the computation of the (weighted) geometric mean G of two positive definite
matrices are described and discussed. For large and sparse matrices the problem of …

An efficient damped Newton-type algorithm with globalization strategy on Riemannian manifolds

MAA Bortoloti, TA Fernandes, OP Ferreira - Journal of Computational and …, 2022 - Elsevier
We propose a new globalization strategy of the damped Newton method for finding
singularities of a vector field on Riemannian manifolds. We establish its global convergence …

The Kahler mean of block-Toeplitz matrices with Toeplitz structured blocks

B Jeuris, R Vandebril - SIAM Journal on matrix analysis and applications, 2016 - SIAM
When one computes an average of positive definite (PD) matrices, the preservation of
additional matrix structure is desirable for interpretations in applications. An interesting and …

Toeplitz Hermitian positive definite matrix machine learning based on Fisher metric

Y Cabanes, F Barbaresco, M Arnaudon… - Geometric Science of …, 2019 - Springer
Here we propose a method to classify radar clutter from radar data using an unsupervised
classification algorithm. The data will be represented by Positive Definite Hermitian Toeplitz …

Robust Burg estimation of radar scatter matrix for autoregressive structured SIRV based on Fréchet medians

A Decurninge, F Barbaresco - IET Radar, Sonar & Navigation, 2017 - Wiley Online Library
The authors address the estimation of the scatter matrix of a scale mixture of Gaussian
stationary autoregressive (AR) vectors. This is equivalent to consider the estimation of a …

Unsupervised machine learning for pathological radar clutter clustering: The p-mean-shift algorithm

Y Cabanes, F Barbaresco, M Arnaudon, J Bigot - C&ESAR 2019, 2019 - hal.science
This paper deals with unsupervised radar clutter clustering to characterize pathological
clutter based on their Doppler fluctuations. Operationally, being able to recognize …

Geometric optimization in machine learning

S Sra, R Hosseini - Algorithmic Advances in Riemannian Geometry and …, 2016 - Springer
Abstract Machine learning models often rely on sparsity, low-rank, orthogonality, correlation,
or graphical structure. The structure of interest in this chapter is geometric, specifically the …