Presentation Information
[B-5A-50]Bit-Domain NOMA to Maximize Total Throughput by Low-Complexity Multiuser Detection
〇Motoshi Tawada1, Kazuhiko Fukawa1 (1. Institute of Science Tokyo)
Keywords:
NOMA,PD-NOMA,BD-NOMA,Spectral efficiency
Non-Orthogonal Multiple Access (NOMA) has attracted considerable attention as a multiple access scheme that can potentially achieve high spectral efficiency in next-generation mobile communications.
In conventional NOMA, Power-Domain NOMA (PD-NOMA), which superposes user signals with different transmit powers, has mainly been employed, and the receiver separates and detects each user signal by using Successive Interference Cancellation (SIC).
However, when the received Signal-to-Noise Ratio (SNR) difference between users is small, the Bit Error Rate (BER) performance and throughput degrade due to error propagation caused by SIC.
To address this problem, this paper focuses on Bit-Domain NOMA (BD-NOMA), which assigns the bit information of multiplexed users to the bit domain of a higher-order modulation scheme.
Specifically, we propose a constellation design method that maximizes the total throughput of two users by using I/Q-based Irregular 16QAM, in which the constellation-point spacings of the I/Q components are made nonuniform.
At the receiver, SIC is not required, and multiuser detection can be performed by simple threshold decision.
In conventional NOMA, Power-Domain NOMA (PD-NOMA), which superposes user signals with different transmit powers, has mainly been employed, and the receiver separates and detects each user signal by using Successive Interference Cancellation (SIC).
However, when the received Signal-to-Noise Ratio (SNR) difference between users is small, the Bit Error Rate (BER) performance and throughput degrade due to error propagation caused by SIC.
To address this problem, this paper focuses on Bit-Domain NOMA (BD-NOMA), which assigns the bit information of multiplexed users to the bit domain of a higher-order modulation scheme.
Specifically, we propose a constellation design method that maximizes the total throughput of two users by using I/Q-based Irregular 16QAM, in which the constellation-point spacings of the I/Q components are made nonuniform.
At the receiver, SIC is not required, and multiuser detection can be performed by simple threshold decision.