activity
20152026
collaborators

13 papers

math.FA2026

Characterization and Construction of Pairwise Orthogonal Parseval Frames with Applications to Sampling

Navneet Redhu, Anupam Gumber, Hartmut Führ +1

In this paper, we provide a characterization of pairwise orthogonal frames with generalized translation-invariant (GTI) structures, based on the unconditional convergence property…

math.FA2025

Ramanujan sums in signal recovery and uncertainty principle inequalities

Sahil Kalra, Niraj K. Shukla

This paper explores the perfect reconstruction property of filter banks based on Ramanujan sums and their applications in signal recovery. Originally introduced by Srinivasa Ramanu…

math.FA2025

Cyclic frames in finite-dimensional Hilbert spaces

Ole Christensen, Navneet Redhu, Niraj K. Shukla

Generalizing a definition by Kalra \cite{Kalra}, the purpose of this paper is to analyze cyclic frames in finite-dimensional Hilbert spaces. Cyclic frames form a subclass of the dy…

math.FA2023

Subspace Dual and orthogonal frames\\ by action of an abelian group

Sudipta Sarka, Niraj K. Shukla

In this article, we discuss subspace duals of a frame of translates by an action of a closed abelian subgroup of a locally compact group These subspace duals are…

math.FA2023

A characterization of MG Dual frames using infimum cosine angle

Sudipta Sarkar, Niraj K. Shukla

This article discusses the construction of dual frames and their uniqueness for the multiplication generated frames on , where is a -finite measure. A ne…

math.FA2023

Reproducing formulas associated to translation generated systems on Nilpotent Lie Groups

Sudipta Sarkar, Niraj K. Shukla

Let be a connected, simply connected, nilpotent Lie group whose irreducible unitary representations are square-integrable modulo the center. We obtain characterization results…

math.FA2022

An Application of the supremum cosine angle between multiplication invariant spaces in $L^2(X; \mc H)$

Sudipta Sarkar, Sahil Kalra, Niraj K. Shukla

In this article, we describe the supremum cosine angle between two multiplication invariant (MI) spaces and its connection with the closedness of the sum of those spaces. The resul…

math.FA2022

Characterizations of Extra-invariant spaces under the left translations on a Lie group

Sudipta Sarkar, Niraj K. Shukla

In the context of a connected, simply connected, nilpotent Lie group, whose representations are square-integrable modulo the center, we find characterization results of extra-invar…

math.FA2020

Microlocal analysis and characterization of Sobolev wavefront sets using shearlets

Bin Han, Swaraj Paul, Niraj K. Shukla

Sobolev wavefront sets and -microlocal spaces play a key role in describing and analyzing the singularities of distributions in microlocal analysis and solutions of partial diff…

math.FA2017

Orthogonality and duality of frames over locally compact abelian groups

Anupam Gumber, Niraj K. Shukla

Motivated by the recent work of Bownik and Ross \cite{BR}, and Jakobsen and Lemvig \cite{JL}, this article generalizes latest results on reproducing formulas for generalized transl…

math.FA2015

Semi-orthogonal Parseval wavelets associated to GMRAs on local fields of positive characteristics

Niraj K. Shukla, Saurabh Chandra Maury, Shiva Mittal

In this article we establish theory of semi-orthogonal Parseval wavelets associated to generalized multiresolution analysis (GMRA) for the local field of positive characteristics (…

math.FA2015

Orthonormal Wavelet System in

Anupam Gumber, Niraj K. Shukla

Using the group theoretic approach based on the set of digits, we first investigate a finite collection of functions in that satisfies some localization…

math.FA2015

Super-wavelets on local fields of positive characteristic

Niraj K. Shukla, Saurabh C. Maury

The concept of super-wavelet was introduced by Balan, and Han and Larson over the field of real numbers which has many applications not only in engineering branches but also in dif…