7 papers
TenSIM: Tensor-Based Channel Estimation for MIMO Systems with Stacked Intelligent Metasurfaces
André L. F. de Almeida, George C. Alexandropoulos
Stacked intelligent metasurfaces (SIMs) are emerging as a promising architecture for sixth-generation (6G) and beyond wireless systems, enabling richer electromagnetic-wave manipul…
Channel Estimation for Beyond Diagonal RIS Exploiting Core Tensor Sparsity
Daniel Costa Araújo, Daniel Costa Araújo, André L. F. de Almeida +1
Beyond diagonal reconfigurable intelligent surfaces (BD-RISs) enhance wave manipulation through inter-element couplings but pose significant channel estimation challenges due to ca…
Semi-Blind Joint Channel and Symbol Estimation for Beyond Diagonal Reconfigurable Surfaces
Gilderlan Tavares de Araújo, André L. F. de Almeida, Buno Sokal +1
The beyond-diagonal reconfigurable intelligent surface (BD-RIS) is a recent architecture in which scattering elements are interconnected to enhance the degrees of freedom for wave…
Semi-Blind Receivers for Hybrid Reflecting and Sensing RIS
Amarilton L. Magalhães, André L. F. de Almeida
Recent research has delved into advanced designs for reconfigurable intelligent surfaces (RIS) with integrated sensing functions. One promising concept is the hybrid RIS (HRIS), wh…
Reducing Complexity of Data-Aided Channel Estimation in RIS-Assisted Communications
Amarilton Lopes Magalhães, André Lima Férrer de Almeida, Gilderlan Tavares de Araújo
We consider the data-aided channel estimation (CE) problem in a reconfigurable intelligent surface (RIS)-assisted wireless communication system, where the channel and information s…
Efficient Techniques for Low-Rank Tensor Approximation and Applications in Robust Object Detection
Salman Ahmadi-Asl, Naeim Rezaeian, Cesar F. Caiafa +1
This paper introduces efficient randomized fixed-precision and single-pass algorithms for low-tubal-rank approximation of third-order tensors. The proposed fixed-precision algorith…