Statistical Parameterization and Realization of Near-Field Spatially Non-Stationary XL-MIMO Channels

Journal article, 2026

Extremely large-scale multiple-input multiple-output (XL-MIMO) is a key enabling technology for sixth-generation (6G) wireless systems, where large antenna arrays lead to pronounced near-field (NF) propagation and spatial non-stationarity (SnS) effects. However, research work on accurate statistical characterization and realization of NF and SnS parameters remains limited, hindering practical stochastic channel modeling. This letter proposes a statistical parameterization and realization framework for NF-SnS XL-MIMO channels. Based on a previously developed NF-SnS model, the key parameters required for stochastic realization are specified, including NF propagation and SnS related parameters. RT simulations are sampled at 29.5 GHz in an indoor multipath environment dominated by line-of-sight (LoS) propagation to extract multipath characteristics and obtain the corresponding parameter distributions. By sampling these fitted distributions, stochastic XL-MIMO channels are realized, generating power delay profiles (PDPs) with controllable SnS power levels. The results demonstrate that the proposed framework accurately reproduces essential NF and SnS features, providing a practical statistical channel model for XL-MIMO evaluation and standardization.