Overview of 3GPP Release 19 Study on Channel Modeling Enhancements to TR 38.901 for 6G

Channel models are a fundamental component of wireless communication systems, providing critical insights into the physics of radio wave propagation. As wireless systems evolve every decade, the development of accurate and standardized channel models becomes increasingly important for the development, evaluation and performance assessment of emerging technologies. An effort to develop a standardized channel model began around 2000 through the Third Generation Partnership Project (3GPP) and the International Telecommunication Union (ITU) with the aim of addressing a broad range of frequencies from sub-1 GHz to 100 GHz. Prior efforts focused heavily on sub-6 GHz bands and mmWave bands, and there exist some gaps in accurately modeling the 7-24 GHz frequency range, a promising candidate band for 6G. To address these gaps, 3GPP approved a Release (Rel) 19 channel modeling study. This study resulted in several enhancements to the channel models, including the ability to accurately model a Suburban Macrocell (SMa) scenario, realistic User Terminal (UT) antenna models, variability in the number of clusters, variability in the number of rays per cluster, a framework for capturing variability in power among all polarizations, near field (NF) propagation, and spatial non-stationarity (SNS) effects, all of which may be crucial for future 6G deployments. This paper presents the outcomes of this study and provides an overview of the underlying rationale, and key discussions that guided the validation, refinement, and enhancements of the 3GPP TR 38.901 channel models.