Hierarchical Cell-Free Massive MIMO for High Capacity with Simple Implementation
Abstract: Cell-free massive multi-input multi-output (MIMO) has recently gained much attention for its potential in shaping the landscape of sixth-generation (6G) wireless systems. This paper proposes a hierarchical network architecture tailored for cell-free massive MIMO, seamlessly integrating co-located and distributed antennas. A central base station (CBS), equipped with an antenna array, positions itself near the center of the coverage area, complemented by distributed access points spanning the periphery. The proposed architecture remarkably outperforms conventional cell-free networks, demonstrating superior sum throughput while maintaining a comparable worst-case per-user spectral efficiency. Meanwhile, the implementation cost associated with the fronthaul network is substantially diminished.
- H. Q. Ngo et al., “Cell-free massive MIMO versus small cells,” IEEE Trans. Wireless Commun., vol. 16, no. 3, pp. 1834–1850, Mar. 2017.
- W. Jiang et al., “The road towards 6G: A comprehensive survey,” IEEE Open J. Commun. Society, vol. 2, pp. 334–366, Feb. 2021.
- E. Nayebi et al., “Precoding and power optimization in cell-free massive MIMO systems,” IEEE Trans. Wireless Commun., vol. 16, no. 7, pp. 4445–4459, Jul. 2017.
- W. Jiang and H. D. Schotten, “Cell-edge performance booster in 6G: Cell-free massive MIMO vs. reconfigurable intelligent surface,” in Proc. IEEE Eur. Conf. on Netw. and Commun. (EUCNC), Gothenburg, Sweden, Jun. 2023, pp. 1–6.
- S. Buzzi and C. D’Andrea, “Cell-free massive MIMO: User-centric approach,” IEEE Wireless Commun. Lett., vol. 6, no. 6, pp. 706–709, Dec. 2017.
- S. Buzzi et al., “User-centric 5G cellular networks: Resource allocation and comparison with the cell-free massive MIMO approach,” IEEE Trans. Wireless Commun., vol. 19, no. 2, pp. 1250–1264, Feb. 2020.
- H. Masoumi and M. J. Emadi, “Performance analysis of cell-free massive MIMO system with limited fronthaul capacity and hardware impairments,” IEEE Trans. Wireless Commun., vol. 19, no. 2, pp. 1038–1052, Feb. 2020.
- W. Zeng et al., “Pilot assignment for cell-free massive MIMO systems using a weighted graphic framework,” IEEE Trans. Veh. Technol., pp. 6190 – 6194, Jun. 2021.
- W. Jiang and H. D. Schotten, “Cell-free massive MIMO-OFDM transmission over frequency-selective fading channels,” IEEE Commun. Lett., vol. 25, no. 8, pp. 2718 – 2722, Aug. 2021.
- W. Jiang and H. Schotten, “Impact of channel aging on zero-forcing precoding in cell-free massive MIMO systems,” IEEE Commun. Lett., vol. 25, no. 9, pp. 3114 – 3118, Sep. 2021.
- B. Hassibi and B. Hochwald, “How much training is needed in multiple-antenna wireless links?” IEEE Trans. Inf. Theory, vol. 49, no. 4, pp. 951 – 963, Apr. 2003.
Paper Prompts
Sign up for free to create and run prompts on this paper using GPT-5.
Top Community Prompts
Collections
Sign up for free to add this paper to one or more collections.