Spectrum Sensing 6G Full duplex Cognitive Radio OFDM Idle cells FBMC Energy Harvesting Ultra-dense small cell networks Bi-Directional stochastic geometry interference management Asynchronous Transmission SINR mismatch problem HetNet Dynamic TDD NOMA Cross-link interference Spectral efficiency bursty traffic model mode selection Device-to-Device (D2D) OQAM Channel estimation error multi-spectral Ultra-dense small cell Heterogeneous channel estimation capability synchronization Bi-directional full-duplex Preamble Intentional frequency offset (IFO) Asynchronism Shortened TTI Deep learning MLP Vehicle-to-vehicle communication Low Earth orbits (LEO) satellite Railway Simultaneous Sensing and Transmission full-duplex relay Cellular networks Latency selection diversity Cognitive relay networks MIMO K-S statistics Long Term Evolution-Advanced 5G networks interference coordination full-duplex cellular interference mitigation sensing duration Correlated MIMO outage probability transmission capacity (TC) Two-way communications self-interference cancellation in-band full-duplex system automatic repeat request (ARQ) achievable sum rate Coexisting network interference to noise ratio link reliability tabu-search massive connectivity resource size control Coexistence scenarios Resource management spectrum sharing mixed numerology Multiple input multiple output (MIMO) New radio non-terrestrial network (NR-NTN) full-spreading NOMA Intentional time offset LTE-based V2V CP-OFDM Singular Vale Decomposition non-orthogonal multiple access Non-orthogonal multiple access (NOMA) Complexity Cooperative systems Reliability B5G Multiple access Cell-free HST Mobility flexible duplex 5G Asynchronous non-orthogonal multiple access (NOMA) Edge computing Full-duplex Filtered OFDM Vehicle-to-Vehicle C-V2V Grant-free Transmission Sub-band filtering Computation offloading TDD configuration Degree of freedom (DoF) Satellite communication
Status : Published 
Date : 2022-04 
Title : How Will Cell-Free Systems Be Deployed? 
Authors : Taehyung Kim, Hyunsoo Kim, Sooyong Choi, and Daesik Hong 
Journal : IEEE Communications Magazine 
Abstract : The cell-free system has recently been investigated as a way to achieve uniform communication performance over the 5G cellular system. However, deploying cell-free systems in commercial mobile networks is a challenging task. One major bottleneck is the need to install access points (AP) on a large scale. APs will be gradually introduced into the mobile system and will need to be compatible with the existing cellular system. As a solution, we propose a transitional system architecture for beyond 5G, where the cell-free system and the legacy cellular system coexist. We call the proposed system a cellfree and legacy coexistence network (CLCN). In this article, the discussion focuses on technical challenges, design considerations, and practical CLCN system layouts. Simulations confirm that the gradual installation of APs in legacy cellular systems can reduce the performance gap between users and improve the average spectral efficiency of the system. The results show that CLCN can provide users uniformly high performance, which has long been a challenge for cellular systems. 
URL : https://ieeexplore.ieee.org/document/9755280 


List of Articles
Status Datesort
3 [IEEE Comm. Surveys & Turotials] Jehyun Heo, Seungwoo Sung, Hyunwoo Lee, Incheol Hwang, and Daesik Hong, "MIMO Satellite Communication Systems: A Survey from the PHY Layer Perspective" in IEEE Communications Surveys & Tutorials Published  2023-07 
» [IEEE Commun. Mag.] Taehyung Kim, Hyunsoo Kim, Sooyong Choi, and Daesik Hong, How Will Cell-Free Systems Be Deployed? in IEEE Communications Magazine, January 2022 Published  2022-04 
1 [IEEE Wireless Commun. Lett.] Hakkeon Lee, Insik Jung, Jehyun Heo, and Daesik Hong, "Exploiting Intentional Time-domain Offset in Downlink Multicarrier NOMA systems", IEEE Wireless Communications Letters, Apr. 2021 Published  2021-04