151 citations · 220 across the 12 of their papers we have counts for
7 papers · 1 filter
Parametric Channel Estimation for RIS-Assisted Wideband Systems
Alva Kosasih, Ozlem Tugfe Demir, Emil Bjornson
A reconfigurable intelligent surface (RIS) alters the reflection of incoming signals based on the phase-shift configuration assigned to its elements. This feature can be used to im…
A New Polar-Domain Dictionary Design for the Near-field Region of Extremely Large Aperture Arrays
Özlem Tuğfe Demir, Emil Björnson
A grid of orthogonal beams with zero column coherence can be easily constructed to cover all prospective user equipments (UEs) in the far-field region of a multiple-antenna base st…
Cell-Free Massive MIMO in O-RAN: Energy-Aware Joint Orchestration of Cloud, Fronthaul, and Radio Resources
Özlem Tuğfe Demir, Meysam Masoudi, Emil Björnson +1
For the energy-efficient deployment of cell-free massive MIMO functionality in a practical wireless network, the end-to-end (from radio site to the cloud) energy-aware operation is…
Exploiting Array Geometry for Reduced-Subspace Channel Estimation in RIS-Aided Communications
Özlem Tuğfe Demir, Emil Björnson, Luca Sanguinetti
A reconfigurable intelligent surface (RIS) can be used to improve the channel gain between a base station (BS) and user equipment (UE), but only if its reflecting elements are…
Cell-Free Massive MIMO in Virtualized CRAN: How to Minimize the Total Network Power?
Özlem Tuğfe Demir, Meysam Masoudi, Emil Björnson +1
Previous works on cell-free massive MIMO mostly consider physical-layer and fronthaul transport aspects. How to deploy cell-free massive MIMO functionality in a practical wireless…
The Bussgang Decomposition of Non-Linear Systems: Basic Theory and MIMO Extensions
Özlem Tuğfe Demir, Emil Björnson
Many of the systems that appear in various signal processing applications are non-linear, for example, due to hardware impairments such as non-linear amplifiers and finite-resoluti…
ADMM-Based One-Bit Quantized Signal Detection for Massive MIMO Systems with Hardware Impairments
Özlem Tugfe Demir, Emil Björnson
This paper considers signal detection in massive multiple-input multiple-output (MIMO) systems with general additive hardware impairments and one-bit quantization. First, we presen…