Sub-Terahertz Spatial Statistical MIMO Channel Model for Urban Microcells at 142 GHz

TL;DR

This paper develops a statistical MIMO channel model for 142 GHz urban microcells, based on measurements, to aid 6G system design at sub-THz frequencies, highlighting the impact of beamforming and spatial clusters.

Contribution

It introduces a detailed spatial statistical MIMO channel model for 142 GHz urban microcells based on empirical measurements, advancing 6G channel modeling accuracy.

Findings

One to four spatial clusters observed at most locations.

Beamforming outperforms spatial multiplexing in LOS scenarios.

Two spatial streams maximize spectral efficiency at NLOS locations.

Abstract

Sixth generation (6G) cellular systems are expected to extend the operational range to sub-Terahertz (THz) frequencies between 100 and 300 GHz due to the broad unexploited spectrum therein. A proper channel model is needed to accurately describe spatial and temporal channel characteristics and faithfully create channel impulse responses at sub-THz frequencies. This paper studies the channel spatial statistics such as the number of spatial clusters and cluster power distribution based on recent radio propagation measurements conducted at 142 GHz in an urban microcell (UMi) scenario. For the 28 measured locations, we observe one to four spatial clusters at most locations. A detailed spatial statistical multiple input multiple output (MIMO) channel generation procedure is introduced based on the derived empirical channel statistics. We find that beamforming provides better spectral efficiency than spatial multiplexing in the LOS scenario due to the boresight path, and two spatial streams usually offer the highest spectral efficiency at most NLOS locations due to the limited number of spatial clusters.