Experimental Modeling of Power Attenuation Factor for Characterizing Spatial Non-Stationary in XL-MIMO Channels

Extremely large-scale Multiple-Input Multiple-Output (XL-MIMO) is envisioned as a promising technology for sixth-generation (6G) communication, with the deployment of extremely large-scale antenna arrays at both the transmitter and receiver in XL-MIMO channels resulting in spatial non-stationary (SnS) characteristics. Although numerous channel measurements and models have been proposed focusing on the SnS characteristics of XL-MIMO channels, few low-complexity channel models characterize the characteristics. This paper proposes a low-complexity experimental model based on the power attenuation factor to characterize SnS. In this paper, channel measurements are conducted at 13 GHz in an indoor office. Analysis of the measurement data reveals significant fluctuations in cluster power along the antenna elements due to SnS. The power attenuation factor is used to model the power variations of clusters caused by SnS. The modeling method effectively captures the SnS characteristics. It provides important references for the XL-MIMO channel modeling research and standardization work.