Directional Wideband Channel Measurements at 28 GHz in an Industrial Environment

Abstract

With the expected adoption of millimeter wave technologies for industrial communication, it is fundamentally important to properly understand the radio channel characteristics of such environments. This paper presents the setup, scenario and results of a measurement campaign at 28 GHz in a machine hall. The radio channel was measured with a bandwidth of 2 GHz and both large scale parameters and directional information were extracted. Evaluation of the power delay profiles shows that the channel contains dense multipath components. A path loss model is parameterized and blockage losses, RMS delay and angle spreads are evaluated. Comparison with the 3GPP TR 38.901 channel model shows that none of the currently defined scenarios is a fit for industrial settings. This emphasizes the need for a newly defined scenario with an industry specific parameter set.

6G Wireless Systems: Vision, Requirements, Challenges, Insights, and Opportunities

“…Tremendous progress is observed in understanding the nature of wave propagation in industrial environments at both sub-6-GHz and mmWave frequencies (see [56] and [160]- [162] for a taxonomy). Naturally, the typical industrial environment is unlike the residential or other indoor environments since the effects of mechanical and electrical noise, as well as interference, are high due to the broad operating temperatures, heavy machinery, and ignition systems [56], [160], [161], [163]. Generally, industrial buildings are taller than ordinary office buildings and are sectioned into several working areas, between which there usually exist straight aisles for transportation of materials or for human traffic.…”

“…The study in [164] proposes a double-directional model with parameters that are tailored at 5 GHz from measured data. A detailed comparison between propagation characteristics at 3.7 and 28 GHz is presented over a bandwidth of 2 GHz in [161], where LOS and NLOS pathloss exponents different to those seen in [162] are reported due to the environmental differences. No substantial difference in the delay spread is seen across the two bands of 3.7-28 GHz.…”

“…Many further investigations are required to understand the time-varying nature of industrial channels at both below 6 GHz and mmWave frequencies, where not many results exist. For further discussions, the reader is referred to [54], [56], [160], [161], [163], and [164].…”

Wideband Channel Characterization for 6G Networks in Industrial Environments

“…Radio propagation measurements at the sub-THz band in indoor industrial environments are expected to attract more research interest [ 40 ]. For instance, a few mmWave radio propagation measurements have been conducted in various industrial environments at 28 GHz [ 44 , 45 , 46 , 47 , 48 , 49 , 50 ] and 60 GHz [ 44 , 51 , 52 ]. Narrowband measurements were conducted inside a factory environment at 28 GHz in [ 46 ] to study the path loss at a 5–100 m distance over 400 LoS and NLoS measured points, and it was shown that the PLE values were 2 and 4.1 for LoS and NLoS, respectively.…”

“…Based on the conducted wideband measurements at 28 GHz in an engineering workshop, it was observed that the reflected and refracted mmWave propagation waves from metallic surfaces were significantly high [ 47 ]. In [ 49 ], based on wideband time domain measurements at 28 GHz with a 2 GHz bandwidth inside a circle-shaped machine hall, the path loss and RMSDS were investigated. It was found that the PLEs of the FI model were 1.9 and 0.9 for LoS and NLoS, respectively, and 1.8 and 2 based on the CI model for LoS and NLoS, respectively.…”