A Novel Non-Stationary Channel Emulator for 6G MIMO Wireless Channels

TL;DR

This paper introduces a new non-stationary MIMO channel emulator for 6G systems that accurately reproduces space-time-frequency channel properties, enabling more realistic performance testing in lab environments.

Contribution

A novel non-stationary MIMO GBSM and a subspace-based reconstruction method for 6G channel emulation are proposed, filling a gap in current channel emulation capabilities.

Findings

The emulator accurately reproduces non-stationary channel characteristics.

Doppler and delay PSDs are consistent between model and emulation.

The approach enhances realistic 6G channel testing in lab settings.

Abstract

The performance evaluation of sixth generation (6G) communication systems is anticipated to be a controlled and repeatable process in the lab, which brings up the demand for wireless channel emulators. However, channel emulation for 6G space-time-frequency (STF) non-stationary channels is missing currently. In this paper, a non-stationary multiple-input multiple-output (MIMO) geometry-based stochastic model (GBSM) that accurately characterizes the channel STF properties is introduced firstly. Then, a subspace-based method is proposed for reconstructing the channel fading obtained from the GBSM and a channel emulator architecture with frequency domain processing is presented for 6G MIMO systems. Moreover, the spatial time-varying channel transfer functions (CTFs) of the channel simulation and the channel emulation are compared and analyzed. The Doppler power spectral density (PSD) and delay PSD are further derived and compared between the channel model simulation and subspace-based emulation. The results demonstrate that the proposed channel emulator is capable of reproducing the non-stationary channel characteristics.