[HTML][HTML] Dynamical sampling and frame representations with bounded operators

O Christensen, M Hasannasab, E Rashidi - Journal of Mathematical …, 2018 - Elsevier
The purpose of this paper is to study frames for a Hilbert space H, having the form {T n φ} n=
0∞ for some φ∈ H and an operator T: H→ H. We characterize the frames that have such a …

Frame properties of operator orbits

O Christensen, M Hasannasab… - Mathematische …, 2020 - Wiley Online Library
We consider sequences in a Hilbert space H of the form (T nf 0) n∈ I, with a linear operator
T, the index set being either I= N or I= Z, a vector f 0∈ H, and answer the following two …

[HTML][HTML] Dynamical sampling for the recovery of spatially constant source terms in dynamical systems

A Aldroubi, RD Martín, I Medri - Linear Algebra and its Applications, 2024 - Elsevier
In this paper, we investigate the problem of source recovery in a dynamical system utilizing
space-time samples. This is a specific issue within the broader field of dynamical sampling …

Robust estimation of smooth graph signals from randomized space–time samples

L Huang, D Needell, S Tang - … and Inference: A Journal of the …, 2024 - academic.oup.com
Heat diffusion processes have found wide applications in modelling dynamical systems over
graphs. In this paper, we consider the recovery of a-bandlimited graph signal that is an initial …

Norm retrieval from few spatio-temporal samples

F Bozkurt, K Kornelson - Journal of Mathematical Analysis and Applications, 2023 - Elsevier
Vectors in a real finite-dimensional Hilbert space that accomplish phase and norm retrieval
can be characterized. In this article, we consider the cases where an operator A is self …

On g-frame representations via linear operators

S Jahedi, F Javadi, MJ Mehdipour - Journal of Pseudo-Differential …, 2023 - Springer
Let {M k} k∈ Z be a sequence of closed subspaces of Hilbert space H, and let {Θ k} k∈ Z be
a sequence of linear operators from H into M k, k∈ Z. In the case where, Θ k is self-adjoint …

On approximate operator representations of sequences in Banach spaces

O Christensen, M Hasannasab, G Steidl - Complex Analysis and Operator …, 2021 - Springer
Generalizing results by Halperin et al., Grivaux recently showed that any linearly
independent sequence {f_k\} _ k= 1^ ∞ fk k= 1∞ in a separable Banach space X can be …

Frames and generalized operator orbits

O Christensen, M Hasannasab - Sampling Theory, Signal Processing, and …, 2023 - Springer
This short note is concerned with various operator representations of frames in a Hilbert
space H. While it is known that only very special frames can be represented in the form {T n …

Representations of frames via iterative actions of operators in tensor product spaces

NK Sahu, S Chauhan, RN Mohapatra - Journal of Pseudo-Differential …, 2023 - Springer
The purpose of this paper is to study the dynamical representation of frames in tensor
product of two Hilbert spaces H 1⊗ H 2. We have considered frames in H 1⊗ H 2 and …

Approximate frame representations via iterated operator systems

O Christensen, M Hasannasab - arXiv preprint arXiv:1910.03535, 2019 - arxiv.org
It is known that it is a very restrictive condition for a frame $\{f_k\} _ {k= 1}^\infty $ to have a
representation $\{T^ n\varphi\} _ {n= 0}^\infty $ as the orbit of a bounded operator $ T …