D-Band Channel Modeling in Data Centers and Industrial Environments

This paper presents D-band channel modeling campaigns for short-range line-of-sight (LOS) communications in representative data center and industrial environments. An accurate multipath estimation framework, exploiting measured antenna radiation patterns, is utilized to extract multipath components (MPCs) with 0.1° angular resolution for precise large- and small-scale channel characterization. In the data center, directional inter-rack communication links exhibit a high path loss exponent (PLE) of 2.39 and a low mean delay spread of 1.32 ns, with cable obstructions increasing the PLE to 3.24 but further decreasing the mean delay spread to 0.59 ns. The omnidirectional measurement in the data center shows significant clustering effects in spatial-temporal domain. In contrast, industrial machine-to-machine (M2M) communication links, characterized through omnidirectional measurements, exhibit a lower PLE of 1.67. Mean values for delay spread, angular spread, and K-factor in industrial environments are moderate, which are 4.35 ns, 16.46°, and 8.11 dB, respectively, with weak clustering effects. The measurement results are compared and discussed with the literature across different environments and frequency bands for an overall understanding of unique propagation characteristics in these two environments. The quantitative measurement results contribute to D-band channel standardization.