11 citations · 20 across the 22 of their papers we have counts for
24 papers
Adaptive Determinantal Client Scheduling in Federated Learning
Wen Xu, Ben Liang, Gary Boudreau +1
Scheduling clients for model training is critical in federated learning due to both data and system heterogeneity. Most previous works focus on the quality of the scheduled clients…
Handoff Design in User-Centric Cell-Free Massive MIMO Networks Using DRL
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
In the user-centric cell-free massive MIMO (UC-mMIMO) network scheme, user mobility necessitates updating the set of serving access points to maintain the user-centric clustering.…
Channel Estimation with Asynchronous Reception for User-Centric Cell-Free MIMO Systems
Xuyang Sun, Hussein A. Ammar, Raviraj Adve +2
The user-centric, cell-free wireless network is a promising next-generation communication system, but signal synchronization issues arise due to distributed access points and lack…
Regularized Top-: A Bayesian Framework for Gradient Sparsification
Ali Bereyhi, Ben Liang, Gary Boudreau +1
Error accumulation is effective for gradient sparsification in distributed settings: initially-unselected gradient entries are eventually selected as their accumulated error exceed…
Novel Gradient Sparsification Algorithm via Bayesian Inference
Ali Bereyhi, Ben Liang, Gary Boudreau +1
Error accumulation is an essential component of the Top- sparsification method in distributed gradient descent. It implicitly scales the learning rate and prevents the slow-down…
Handoffs in User-Centric Cell-Free MIMO Networks: A POMDP Framework
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
We study the problem of managing handoffs (HOs) in user-centric cell-free massive MIMO (UC-mMIMO) networks. Motivated by the importance of controlling the number of HOs and by the…
The Internet of Senses: Building on Semantic Communications and Edge Intelligence
Roghayeh Joda, Medhat Elsayed, Hatem Abou-zeid +5
The Internet of Senses (IoS) holds the promise of flawless telepresence-style communication for all human `receptors' and therefore blurs the difference of virtual and real environ…
POMDP-based Handoffs for User-Centric Cell-Free MIMO Networks
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
We propose to control handoffs (HOs) in user-centric cell-free massive MIMO networks through a partially observable Markov decision process (POMDP) with the state space representin…
Online Distributed Coordinated Precoding for Virtualized MIMO Networks with Delayed CSI
Juncheng Wang, Ben Liang, Min Dong +2
We consider online wireless network virtualization (WNV) in a multi-cell multiple-input multiple output (MIMO) system with delayed feedback of channel state information (CSI). Mult…
Analysis and Design of Distributed MIMO Networks with a Wireless Fronthaul
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +1
We consider the analysis and design of distributed wireless networks wherein remote radio heads (RRHs) coordinate transmissions to serve multiple users on the same resource block (…
Distributed Resource Allocation Optimization for User-Centric Cell-Free MIMO Networks
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
We develop two distributed downlink resource allocation algorithms for user-centric, cell-free, spatially-distributed, multiple-input multiple-output (MIMO) networks. In such netwo…
RWP+: A New Random Waypoint Model for High-Speed Mobility
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
In this letter, we emulate real-world statistics for mobility patterns on road systems. We then propose modifications to the assumptions of the random waypoint (RWP) model to bette…
Downlink Resource Allocation in Multiuser Cell-free MIMO Networks with User-centric Clustering
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
In this paper, we optimize user scheduling, power allocation and beamforming in distributed multiple-input multiple-output (MIMO) networks implementing user-centric clustering. We…
Hierarchical Online Convex Optimization
Juncheng Wang, Ben Liang, Min Dong +2
We consider online convex optimization (OCO) over a heterogeneous network with communication delay, where multiple workers together with a master execute a sequence of decisions to…
Resource Allocation for Massive MIMO HetNets with Quantize-Forward Relaying
Ahmad Abu Al Haija, Min Dong, Ben Liang +1
We investigate how massive MIMO impacts the uplink transmission design in a heterogeneous network (HetNet) where multiple users communicate with a macro-cell base station (MCBS) wi…
Online Multi-Cell Coordinated MIMO Wireless Network Virtualization with Imperfect CSI
Juncheng Wang, Ben Liang, Min Dong +1
We consider online coordinated precoding design for downlink wireless network virtualization (WNV) in a multi-cell multiple-input multiple-output (MIMO) network with imperfect chan…
Delay-Tolerant Constrained OCO with Application to Network Resource Allocation
Juncheng Wang, Ben Liang, Min Dong +2
We consider online convex optimization (OCO) with multi-slot feedback delay, where an agent makes a sequence of online decisions to minimize the accumulation of time-varying convex…
Distributed coordinated precoding for MIMO cellular network virtualization
Juncheng Wang, Min Dong, Ben Liang +2
This paper presents a new virtualization method for the downlink of a multi-cell multiple-input multiple-output (MIMO) network, to achieve service isolation among multiple Service…
User-centric Cell-free Massive MIMO Networks: A Survey of Opportunities, Challenges and Solutions
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
Densification of network base stations is indispensable to achieve the stringent Quality of Service (QoS) requirements of future mobile networks. However, with a dense deployment o…
Periodic Updates for Constrained OCO with Application to Large-Scale Multi-Antenna Systems
Juncheng Wang, Min Dong, Ben Liang +1
In many dynamic systems, decisions on system operation are updated over time, and the decision maker requires an online learning approach to optimize its strategy in response to th…
Optimizing RRH Placement Under a Noise-Limited Point-to-Point Wireless Backhaul
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +1
In this paper, we study the deployment decisions and location optimization for the remote radio heads (RRHs) in coordinated distributed networks in the presence of a wireless backh…
Resource Allocation and Scheduling in Non-coherent User-centric Cell-free MIMO
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +2
We study the problem of user-scheduling and resource allocation in distributed multi-user, multiple-input multiple-output (MIMO) networks implementing user-centric clustering and n…
Statistical Analysis of Downlink Zero-Forcing Beamforming
Hussein A. Ammar, Raviraj Adve, Shahram Shahbazpanahi +1
We analyze the mean and the variance of the useful signal and interference powers in a multi-cell network using zero-forcing beamforming (ZF-BF) with two beamformer normalization a…
An Efficient Clustering Algorithm for Device-to-Device Assisted Virtual MIMO
S. Hossein Seyedmehdi, Gary Boudreau
In this paper, the utilization of mobile devices (MDs) as decode-and-forward relays in a device-to-device assisted virtual MIMO (VMIMO) system is studied. Single antenna MDs are ra…