29 citations · 104 across the 14 of their papers we have counts for
16 papers
CUNEC: A Path Loss Model for Urban Cell-Free Massive MIMO Networks
Thomas Choi, Yuning Zhang, Issei Kanno +2
Accurate path loss (PL) modeling is essential for evaluating and optimizing cell-free massive MIMO systems, especially in dense urban environments where traditional models fail to…
Large-scale Outdoor Cell-free mMIMO Channel Measurement in an Urban Scenario at 3.5 GHz
Yuning Zhang, Thomas Choi, Zihang Cheng +14
The design of cell-free massive MIMO (CF-mMIMO) systems requires accurate, measurement-based channel models. This paper provides the first results from the by far most extensive ou…
Cell-free massive MIMO Channels in an Urban Environment -- Measurements and Channel Statistics
Yuning Zhang, Thomas Choi, Zihang Cheng +4
Cell-free massive MIMO (CF-mMIMO), where each user equipment (UE) is connected to multiple access points (APs), is emerging as an important component for 5G and 6G cellular systems…
Energy Efficiency of Uplink Cell-Free Massive MIMO With Transmit Power Control in Measured Propagation Channel
Thomas Choi, Masaaki Ito, Issei Kanno +5
Cell-free massive MIMO (CF-mMIMO) provides wireless connectivity for a large number of user equipments (UEs) using access points (APs) distributed across a wide area with high spec…
Evaluation on Energy Efficiency of UE in UL Cell-Free Massive MIMO System With Power Control Methods
Masaaki Ito, Issei Kanno, Takeo Ohseki +4
Cell-free massive multiple-input multiple-output (CF mMIMO) systems are expected to provide faster and more robust connections to user equipments (UEs) by cooperation of a massive…
Uplink Energy Efficiency of Cell-Free Massive MIMO With Transmit Power Control in Measured Propagation Channels
Thomas Choi, Masaaki Ito, Issei Kanno +3
Cell-free massive MIMO (CF-mMIMO) is expected to provide reliable wireless services for a large number of user equipments (UEs) using access points (APs) distributed across a wide…
Using a Drone Sounder to Measure Channels for Cell-Free Massive MIMO Systems
Thomas Choi, Jorge Gomez-Ponce, Colton Bullard +5
Measurements of the propagation channel form the basis of all realistic system performance evaluations, as foundation of statistical channel models or to verify ray tracing. This i…
Air-to-Ground Directional Channel Sounder With 64-antenna Dual-polarized Cylindrical Array
Jorge Gomez Ponce, Thomas Choi, Naveed A. Abbasi +7
Unmanned Aerial Vehicles (UAVs), popularly called drones, are an important part of future wireless communications, either as user equipment that needs communication with a ground s…
Co-Located vs Distributed vs Semi-Distributed MIMO: Measurement-Based Evaluation
Thomas Choi, Peng Luo, Akshay Ramesh +1
With the growing interest in cell-free massive multiple-input multiple-output (MIMO) systems, the benefits of single-antenna access points (APs) versus multi-antenna APs must be an…
Robust Non-Coherent Beamforming for FDD Downlink Massive MIMO
François Rottenberg, Ming-Chun Lee, Thomas Choi +2
Designing beamforming techniques for the downlink (DL) of frequency division duplex (FDD) massive MIMO is known to be a challenging problem due to the difficulty of obtaining chann…
Experimental Investigation of Frequency Domain Channel Extrapolation in Massive MIMO Systems for Zero-Feedback FDD
Thomas Choi, François Rottenberg, Jorge Gomez-Ponce +4
Estimating downlink (DL) channel state information (CSI) in frequency division duplex (FDD) massive multi-input multi-output (MIMO) systems generally requires downlink pilots and f…
Channel Extrapolation for FDD Massive MIMO: Procedure and Experimental Results
Thomas Choi, François Rottenberg, Jorge Gomez-Ponce +4
Application of massive multiple-input multiple-output (MIMO) systems to frequency division duplex (FDD) is challenging mainly due to the considerable overhead required for downlink…
Performance Analysis of Channel Extrapolation in FDD Massive MIMO Systems
Francois Rottenberg, Thomas Choi, Peng Luo +2
Channel estimation for the downlink of frequency division duplex (FDD) massive MIMO systems is well known to generate a large overhead as the amount of training generally scales wi…
How Many Antennas Do We Need for Massive MIMO Channel Sounding? - Validating Through Measurement
Thomas Choi, François Rottenberg, Peng Luo +2
This paper investigates the impact of the number of antennas (8 to 64) and the array configuration on massive MIMO channel parameters estimation for multiple propagation scenarios…
Enable Super-resolution Parameter Estimation for Mm-wave Channel Sounding
Rui Wang, C. Umit Bas, Zihang Cheng +14
This paper investigates the capability of millimeter-wave (mmWave) channel sounders with phased arrays to perform super-resolution parameter estimation, i.e., determine the paramet…
Outdoor to Indoor Penetration Loss at 28 GHz for Fixed Wireless Access
C. Umit Bas, Rui Wang, Thomas Choi +5
This paper present the results from a 28 GHz channel sounding campaign performed to investigate the effects of outdoor to indoor penetration on the wireless propagation channel cha…