Samsung R&D Institute China-Beijing (SRC-B) published three papers recently accepted by the 97th Institute of Electrical and Electronics Engineers (IEEE) Vehicular Technology Conference: VTC2023-Spring, to be held in Florence from June 20 to 23, 2023. This semiannual flagship conference of the IEEE VTC will bring together individuals from academia, the government, and industry to discuss and exchange ideas in the wireless, mobile, and vehicular technology fields. These papers accepted by VTC represent Samsung’s breakthroughs and innovations in the 5th generation mobile network (5G) field.

1.“High-Reliability Transmission Scheme for Anchored Indoor New Radio Unlicensed Systems”

This paper investigates high-reliability transmission for anchored indoor New Radio Unlicensed (NR-U) systems. One successful transmission-ensuring scheme is proposed for indoor NR-U deployment to achieve high-reliability transmission using an unlicensed spectrum. Simulation results proved that the proposed successful transmission-ensuring scheme significantly decreases the retransmission ratio and provides less transmission latency and higher throughput.

In this paper, the success transmission probability (STP) of NR-U has been first modeled with historical Listen Before Talk (LBT) results by using the nonlinear Levenberg-Marquardt method. The STP-based packet request algorithm for initial transmission and the STP-based channel allocation algorithm for Automatic Repeat reQuest (ARQ) retransmission were used to enhance the performance of the NR-U system. Simulation results have demonstrated the proposed algorithm ensures high-reliability NR-U transmission with more than 50% ReTx ratio reduction and less than 0.5% dropped packet ratio. Meanwhile, it reduces 73% packet transmission latency and brings more than 43.6% throughput gain. In short, this paper provides an effective solution that satisfies the high-reliability transmission requirement for NR-U.

Link to the paper
https://ieeexplore.ieee.org/document/10199363

2. “Projection Riemannian Manifold-based Regular Sparse Array Beamforming for Millimeter Wave Communication”

This paper proposes Projection Riemannian Manifold (PRM)-based Regular Sparse Array (RSA) beamforming to reduce hardware cost and power consumption.

RSA is first obtained by removing parts of antenna elements from a uniform array and introducing them into millimeter wave (mmWave) networks, enabling implementation feasibility. The mathematical modeling and residual error algorithm are proposed to derive a minimal antenna number for RSA. Furthermore, PRM is proposed to generate a beam book with nonlinear constraints and boost the coverage with fewer antennas. In addition, we are the first to suggest a P-R beamforming framework interlacing both PRM and RSA with MMSE verification. From performance evaluation and theoretical analysis, the proposed P-R beamforming algorithm can reduce at least 15% of the hardware cost and power consumption with negligible performance loss.

Link to the paper
https://ieeexplore.ieee.org/document/10200832

3. “A Collision Probability-based Multiuser Grant-Free Scheduling Method for Ultrareliable and Low-Latency Communications”

Predicting the exact packet arrival time of User Equipment (UE) is challenging for a base station for uplink transmission in an Ultrareliable and Low-Latency Communication (URLLC) system. Without knowing the exact time of UE packets, grant-free scheduling, a key enabler to support uplink URLLC, becomes challenging for guaranteeing network resource utilization and UE capacity while ensuring the performance of URLLC.

This paper proposes a Collision Probability-based Multiuser (CPMU) grant-free resource allocation method to select an appropriate sending time occasion set and frequency multiplexed scheduling user set for a multiuser multi-input multi-output (MU-MIMO) network. Simulation results show the proposed method improves system resource utilization from 10% up to 341% and increases UE capacity from 25% up to 400%, while the URLLC performance is guaranteed.

Link to the paper
https://ieeexplore.ieee.org/abstract/document/10199833