arXiv subjects

Alexander Sherstobitov

Publications and source records attributed to Alexander Sherstobitov.

2 recordsLinked to original sources

arXiv2026

Mode-Tensorized Canonical Polyadic Decomposition for MIMO Channel Estimation

This paper proposes a channel estimation method for Multiple-Input Multiple-Output (MIMO) systems based on Canonical Polyadic (CP) decomposition applied to a mode-factorized tensor representation of the channel. The proposed approach reshapes the original low-order channel tensor into a higher-order tensor by factorizing its modes into multiple virtual modes, thereby introducing additional dimensions. By exploiting the sparse structure of MIMO channels and the plane-wave propagation model in the far-field regime, the proposed mode tensorization enhances the separability of individual propagation paths. It is shown that increasing the number of tensor modes improves component separation and provides inherent denoising effects. Building on these properties, a mode-tensorized CP decomposition (MTCPD) algorithm is developed. In addition, a metric for analyzing the virtual factors obtained from MTCPD is proposed, enabling estimation of the canonical rank and selection of the most informative components contributing to overall system performance. Numerical results demonstrate that the proposed method improves channel estimation accuracy compared to conventional tensor-based approaches, particularly under low signal-to-noise ratio conditions.

cs.IT↗

arXiv2022

A 2D-programmable and Scalable Reconfigurable Intelligent Surface Remotely Controlled via Digital Infrared Code

Reconfigurable Intelligent Surfaces (RISs) are promising and relatively low-cost tools for improving signal propagation in wireless communications. An RIS assists a base station in optimizing the channel and maximizing its capacity by dynamically manipulating with reflected field. Typically, RISs are based on dynamically reconfigurable reflectarrays, i.e. two-dimensional arrays of passive patch antennas, individually switchable between two or more reflection phases. Different communication scenarios and environments require RISs to provide a different spatial resolution of reflected field patterns, which depends on the aperture dimensions and the number of patches. Here we demonstrate a 1-bit RIS for 5-GHz Wi-Fi band made by assembling together multiple independently operating building blocks all powered by the same DC source. Each block contains four separately phase-switchable patch antennas with varactor diodes and a common microcontroller extracting digital control commands from modulated infrared light illuminating the entire RIS. Such distributed light-sensitive controllers grant the possibility of scaling the aperture by adding or removing blocks without re-designing any control circuitry. Moreover, in the proposed RIS a full 2D phase encoding capability is achieved along with a robust remote infrared control.

eess.SP↗