154 citations · 258 across the 14 of their papers we have counts for
14 papers
Beam Training for RIS-Aided ISAC Systems
Jinho Yang, Hyeongtaek Lee, Junil Choi
As a key technology for 6G, integrated sensing and communication (ISAC) is receiving considerable attention, and deploying a reconfigurable intelligent surface (RIS) can enhance bo…
Downlink Channel Estimation for mmWave Systems with Impulsive Interference
Kwonyeol Park, Gyoseung Lee, Hyeongtaek Lee +2
In this paper, we investigate a channel estimation problem in a downlink millimeter-wave (mmWave) multiple-input multiple-output (MIMO) system, which suffers from impulsive interfe…
Task-Based Quantization for Channel Estimation in RIS Empowered MmWave Systems
Gyoseung Lee, In-soo Kim, Yonina C. Eldar +4
In this paper, we investigate channel estimation for reconfigurable intelligent surface (RIS) empowered millimeter-wave (mmWave) multi-user single-input multiple-output communicati…
Robust Transmission Design for Active RIS-Aided Systems
Jinho Yang, Hyeongtaek Lee, Junil Choi
Different from conventional passive reconfigurable intelligent surfaces (RISs), incident signals and thermal noise can be amplified at active RISs. By exploiting the amplifying cap…
An Experimental Multi-Band Channel Characterization in the Upper Mid-Band
Roberto Bomfin, Ahmad Bazzi, Hao Guo +5
The following paper provides a multi-band channel measurement analysis on the frequency range (FR)3. This study focuses on the FR3 low frequencies 6.5 GHz and 8.75 GHz with a setup…
RIS-Enabled Cellular Systems Operated by Different Service Providers
Hyeongtaek Lee, Junil Choi
In realistic cellular communication systems, multiple service providers will operate within different frequency ranges. Each serving cell, which is managed by a distinct service pr…
Multi-Group Multicasting Systems Using Multiple RISs
Hyeongtaek Lee, Seungsik Moon, Youngjoo Lee +3
In this paper, practical utilization of multiple distributed reconfigurable intelligent surfaces (RISs), which are able to conduct group-specific operations, for multi-group multic…
Joint Downlink and Uplink Optimization for RIS-Aided FDD MIMO Communication Systems
Gyoseung Lee, Hyeongtaek Lee, Donghwan Kim +3
This paper investigates reconfigurable intelligent surface (RIS)-aided frequency division duplexing (FDD) communication systems. Since the downlink and uplink signals are simultane…
Channel Estimation for Reconfigurable Intelligent Surface with a few Active Elements
Gyoseung Lee, Hyeongtaek Lee, Jaeky Oh +2
In this paper, a channel estimation technique for reconfigurable intelligent surface (RIS)-aided multi-user multiple-input single-output communication systems is proposed. By deplo…
Practical Channel Estimation and Phase Shift Design for Intelligent Reflecting Surface Empowered MIMO Systems
Sucheol Kim, Hyeongtaek Lee, Jihoon Cha +3
In this paper, channel estimation techniques and phase shift design for intelligent reflecting surface (IRS)-empowered single-user multiple-input multiple-output (SU-MIMO) systems…
Complete Power Reallocation for MU-MIMO under Per-Antenna Power Constraint
Sucheol Kim, Hyeongtaek Lee, Hwanjin Kim +2
This paper proposes a beamforming method under a per-antenna power constraint (PAPC). Although many beamformer designs with the PAPC need to solve complex optimization problems, th…
Downlink Channel Reconstruction for Spatial Multiplexing in Massive MIMO Systems
Hyeongtaek Lee, Hyuckjin Choi, Hwanjin Kim +4
To get channel state information (CSI) at a base station (BS), most of researches on massive multiple-input multiple-output (MIMO) systems consider time division duplexing (TDD) to…
Massive MIMO Channel Prediction: Kalman Filtering vs. Machine Learning
Hwanjin Kim, Sucheol Kim, Hyeongtaek Lee +3
This paper focuses on channel prediction techniques for massive multiple-input multiple-output (MIMO) systems. Previous channel predictors are based on theoretical channel models,…
Efficient Channel AoD/AoA Estimation Using Widebeams for Millimeter Wave MIMO Systems
Hyeongtaek Lee, Sucheol Kim, Junil Choi
Using millimeter-wave (mmWave) bands is expected to provide high data rates through large licensed and unlicensed spectrum. Due to large path loss and sparse scattering propagation…