Saved in:
Bibliographic Details
Main Authors: Lyu, Lei, Mitra, Urbashi
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2509.10770
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915493564121088
author Lyu, Lei
Mitra, Urbashi
author_facet Lyu, Lei
Mitra, Urbashi
contents In this paper, the hybrid sparse/diffuse (HSD) channel model in frequency domain is proposed. Based on the structural analysis on the resolvable paths and diffuse scattering statistics in the channel, the Hybrid Atomic-Least-Squares (HALS) algorithm is designed to estimate sparse/diffuse components with a combined atomic and l2 regularization. A theoretical analysis is conducted on the Lagrangian dual problem and the conditions needed to be satisfied by primal and dual solutions are provided. This analysis, in turn, suggests an algorithm for optimal frequency support estimation. Debiased methods for improved channel estimation are provided. Given differing amounts of side information, performance bounds are derived in terms of a genie-aided estimator and constrained Cramer-Rao lower bounds (CRLB). Numerical results via simulations on synthetic data as well as real experimental data validate the efficacy of the proposed method. There are clear tradeoffs with respect to the properties of the channel with respect to performance: sparsity of specular paths and relative energy of diffuse components.
format Preprint
id arxiv_https___arxiv_org_abs_2509_10770
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Hybrid Atomic Norm Sparse/Diffuse Channel Estimation
Lyu, Lei
Mitra, Urbashi
Signal Processing
In this paper, the hybrid sparse/diffuse (HSD) channel model in frequency domain is proposed. Based on the structural analysis on the resolvable paths and diffuse scattering statistics in the channel, the Hybrid Atomic-Least-Squares (HALS) algorithm is designed to estimate sparse/diffuse components with a combined atomic and l2 regularization. A theoretical analysis is conducted on the Lagrangian dual problem and the conditions needed to be satisfied by primal and dual solutions are provided. This analysis, in turn, suggests an algorithm for optimal frequency support estimation. Debiased methods for improved channel estimation are provided. Given differing amounts of side information, performance bounds are derived in terms of a genie-aided estimator and constrained Cramer-Rao lower bounds (CRLB). Numerical results via simulations on synthetic data as well as real experimental data validate the efficacy of the proposed method. There are clear tradeoffs with respect to the properties of the channel with respect to performance: sparsity of specular paths and relative energy of diffuse components.
title Hybrid Atomic Norm Sparse/Diffuse Channel Estimation
topic Signal Processing
url https://arxiv.org/abs/2509.10770