TY  - JOUR
T1  - Analysis on the Number of Users in MRT and MRC Based Full-Duplex Massive MIMO Systems
AU  - Min, Kyungsik 
JO  - The Journal of Korean Institute of Communications and Information Sciences
PY  - 2025
DA  - 2025/1/1
DO  - 10.7840/kics.2025.50.7.1031
KW  - Full-duplex massive MIMO
KW  - number of users
AB  - In this paper, the number of users to maximize the sum-rate of full-duplex massive multiple-input multiple-output (MIMO) systems is analyzed. For full-duplex data transmission and reception with multiple antennas at the base station (BS), maximum ratio transmission and combining are considered. Based on a large number of antennas at the BS, closed-form expressions of downlink and uplink sum-rates based on maximum ratio transmission (MRT) and maximum ratio combining (MRC) are derived, respectively. Then, an optimization problem to find the numbers of downlink and uplink users maximizing the total sum-rate is formulated. It is analyzed that the numbers of downlink and uplink users to maximize sum-rates are equal to the number of BS antennas. It is verified that the derived sum-rate is well aligned with simulation results, and the analyzed numbers of downlink and uplink users maximize the total sum-rate of the full-duplex massive MIMO system based on MRT and MRC.