학술논문

Lightweight Machine Learning for Digital Cross-Link Interference Cancellation With RF Chain Characteristics in Flexible Duplex MIMO Systems
Document Type
Periodical
Source
IEEE Wireless Communications Letters IEEE Wireless Commun. Lett. Wireless Communications Letters, IEEE. 12(7):1269-1273 Jul, 2023
Subject
Communication, Networking and Broadcast Technologies
Computing and Processing
Signal Processing and Analysis
Interference
Receiving antennas
Radio frequency
MIMO communication
Transmitting antennas
Channel models
Channel estimation
Flexible duplex
dynamic TDD/FDD
cross-link interference
6G
machine learning
MIMO
RF chain
Language
ISSN
2162-2337
2162-2345
Abstract
The flexible duplex (FD) technique, including dynamic time-division duplex (D-TDD) and dynamic frequency-division duplex (D-FDD), is regarded as a promising solution to achieving a more flexible uplink/downlink transmission in 5G-Advanced or 6G mobile communication systems. However, it may introduce serious cross-link interference (CLI). For better mitigating the impact of CLI, we first present a more realistic base station (BS)-to-BS channel model incorporating the radio frequency (RF) chain characteristics, which exhibit a hardware-dependent nonlinear property, and hence the accuracy of conventional channel modelling is inadequate for CLI cancellation. Then, we propose a channel parameter estimation based polynomial CLI canceller and two machine learning (ML) based CLI cancellers that use the lightweight feedforward neural network (FNN). Our simulation results and analysis show that the ML based CLI cancellers achieve notable performance improvement and dramatic reduction of computational complexity, in comparison with the polynomial CLI canceller.