64 citations · 102 across the 31 of their papers we have counts for
31 papers
Mask-Compliant Clipping-Aware Precoding for Multi-User MIMO-OFDM Systems
Navid Reyhanian, Parisa Ramezani, Emil Björnson
Orthogonal frequency-division multiplexing (OFDM) is widely adopted in frequency-selective channels for its ability to simplify equalization, yet it also causes large signal peaks,…
Swarm and Evolutionary Computation for Near-Field Localization
Parisa Ramezani, Seyed Jalaleddin Mousavirad, Mattias O'Nils +1
Near-field localization has attracted significant attention in recent years due to the move toward higher frequencies and extremely large aperture arrays, which expand the near-fie…
Symbol-Level Mask-Compliant Hybrid Precoding for Multi-User MIMO-OFDM Systems
Navid Reyhanian, Parisa Ramezani, Emil Björnson
Millimeter-wave (mmWave) technology is a crucial enabler for next-generation networks because it offers substantially greater available bandwidth. mmWave multiple-input multiple-ou…
Joint and Streamwise Distributed MIMO Satellite Communications with Multi-Antenna Ground Users
Parisa Ramezani, Emil Björnson
We consider a low Earth orbit downlink communication, where multiple satellites jointly serve multi-antenna ground users, transmitting multiple spatial streams per user. Using a li…
A Primer on Evolutionary Optimization Frameworks for Near-Field Multi-Source Localization
Seyed Jalaleddin Mousavirad, Parisa Ramezani, Mattias O'Nils +1
This paper introduces evolutionary optimization as a grid-free training-free continuous-domain search mechanism for near-field multi-source localization, addressing the major limit…
Maximum A Posteriori Probability Channel Tracking with an Intelligent Transmitting Surface
Parisa Ramezani, Alva Kosasih, Emil Björnson
This paper considers an intelligent transmitting surface (ITS) integrated into a base station and develops a low-overhead maximum a posteriori (MAP) probability channel tracking me…
Cell-Free MIMO in Space: Cooperative Satellite Transmission with Multi-Antenna Ground Users
Parisa Ramezani, Emil Björnson
This paper develops a multi-user downlink communication framework for distributed low Earth orbit satellite networks serving ground users equipped with multiple antennas. Building…
Precoding for Uplink RIS-Assisted Cell-Free MIMO-OFDM Systems with Hardware Impairments
Navid Reyhanian, Reza Ghaderi Zefreh, Parisa Ramezani +1
This paper studies a reconfigurable intelligent surface (RIS)-assisted cell-free massive multiple-input multiple-output (CF-mMIMO) system with multiple RISs. Joint design of transm…
Joint Spatial and Spectral Hybrid Precoding for Multi-User MIMO-OFDM Systems
Navid Reyhanian, Reza Ghaderi Zefreh, Parisa Ramezani +1
Millimeter wave (mmWave) multiple-input multiple-output (MIMO) systems operate over wide bandwidths and frequency-selective channels, making orthogonal frequency-division multiplex…
Machine Learning-Based Near-Field Localization in Mixed LoS/NLoS Scenarios
Parisa Ramezani, Seyed Jalaleddin Mousavirad, Mattias O'Nils +1
The conventional MUltiple SIgnal Classification (MUSIC) algorithm is effective for angle-of-arrival estimation in the far-field and can be extended for full source localization in…
Limited-Resolution Hybrid Analog-Digital Precoding Design Using MIMO Detection Methods
Parisa Ramezani, Alva Kosasih, Emil Björnson
While fully-digital precoding achieves superior performance in massive MIMO systems, it comes with significant drawbacks in terms of computational complexity and power consumption,…
A Novel Hybrid Precoder With Low-Resolution Phase Shifters and Fronthaul Capacity Limitation
Parisa Ramezani, Alva Kosasih, Emil Björnson
In massive MIMO systems, fully digital precoding offers high performance but has significant implementation complexity and energy consumption, particularly at millimeter frequencie…
On Broad-Beam Reflection for Dual-Polarized RIS-Assisted MIMO Systems
Parisa Ramezani, Maksym A. Girnyk, Emil Björnson
The use of a reconfigurable intelligent surface (RIS) for aiding user-specific transmission has been widely explored. However, little attention has been devoted to utilizing RIS fo…
An Efficient Modified MUSIC Algorithm for RIS-Assisted Near-Field Localization
Parisa Ramezani, Alva Kosasih, Emil Björnson
In this paper, we consider a single-anchor localization system assisted by a reconfigurable intelligent surface (RIS), where the objective is to localize multiple user equipments (…
Enabling 6G Performance in the Upper Mid-Band by Transitioning From Massive to Gigantic MIMO
Emil Björnson, Ferdi Kara, Nikolaos Kolomvakis +3
The initial 6G networks will likely operate in the upper mid-band (7-24 GHz), which has decent propagation conditions but underwhelming new spectrum availability. In this paper, we…
MSE Minimization in RIS-Aided MU-MIMO with Discrete Phase Shifts and Fronthaul Quantization
Parisa Ramezani, Yasaman Khorsandmanesh, Emil Björnson
In this paper, we consider a downlink multi-user multiple-input multiple-output (MU-MIMO) communication assisted by a reconfigurable intelligent surface (RIS) and study the precodi…
Near-Field Localization and Sensing with Large-Aperture Arrays: From Signal Modeling to Processing
Zhaolin Wang, Parisa Ramezani, Yuanwei Liu +1
The signal processing community is currently witnessing a growing interest in near-field signal processing, driven by the trend towards the use of large aperture arrays with high s…
Joint Discrete Precoding and RIS Optimization for RIS-Assisted MU-MIMO Communication Systems
Parisa Ramezani, Yasaman Khorsandmanesh, Emil Björnson
This paper considers a multi-user multiple-input multiple-output (MU-MIMO) system where the downlink communication between a base station (BS) and multiple user equipments (UEs) is…
Localization in Massive MIMO Networks: From Near-Field to Far-Field
Parisa Ramezani, Özlem Tuğfe Demir, Emil Björnson
Source localization is the process of estimating the location of signal sources based on the signals received at different antennas of an antenna array. It has diverse applications…
A Novel Discrete Phase Shift Design for RIS-Assisted Multi-User MIMO
Parisa Ramezani, Yasaman Khorsandmanesh, Emil Björnson
Reconfigurable intelligent surface (RIS) is a newly-emerged technology that might fundamentally change how wireless networks are operated. Though extensively studied in recent year…
Broad Beam Reflection for RIS-Assisted MIMO Systems with Planar Arrays
Parisa Ramezani, Maksym A. Girnyk, Emil Björnson
While reconfigurable intelligent surface (RIS)-aided user-specific beamforming has been vastly investigated, the aspect of utilizing RISs for assisting cell-specific transmission h…
Dual-Polarized Reconfigurable Intelligent Surface Assisted Broad Beamforming
Parisa Ramezani, Maksym A. Girnyk, Emil Björnson
A reconfigurable intelligent surface (RIS) consists of a large number of low-cost elements that can control the propagation environment seen from a transmitter by intelligently app…
Parametric Channel Estimation with Short Pilots in RIS-Assisted Near- and Far-Field Communications
Mehdi Haghshenas, Parisa Ramezani, Maurizio Magarini +1
Considering the dimensionality of a typical reconfigurable intelligent surface (RIS), channel state information acquisition in RIS-assisted systems requires lengthy pilot transmiss…
Exploiting the Depth and Angular Domains for Massive Near-Field Spatial Multiplexing
Parisa Ramezani, Alva Kosasih, Amna Irshad +1
In this article, we present our vision for how extremely large aperture arrays (ELAAs), equipped with hundreds or thousands of antennas, can play a major role in future 6G networks…