Sub-Terahertz (THz) frequencies between 100 GHz
and 300 GHz are being considered as a key enabler for the sixthgeneration
(6G) wireless communications due to the vast amounts
of unused spectrum. The 3rd Generation Partnership Project
(3GPP) included the indoor industrial environments as a scenario
of interest since Release 15. This paper presents recent sub-
THz channel measurements using directional horn antennas of
27 dBi gain at 142 GHz in a factory building, which hosts equipment
manufacturing startups. Directional measurements with copolarized
and cross-polarized antenna configurations were conducted
over distances from 6 to 40 meters. Omnidirectional and
directional path loss with two antenna polarization configurations
produce the gross cross-polarization discrimination (XPD) with
a mean of 27.7 dB, which suggests that dual-polarized antenna
arrays can provide good multiplexing gain for sub-THz wireless
systems. The measured power delay profile and power angular
spectrum show the maximum root mean square (RMS) delay
spread of 66.0 nanoseconds and the maximum RMS angular
spread of 103.7 degrees using a 30 dB threshold, indicating the
factory scenario is a rich-scattering environment due to a massive
number of metal structures and objects. This work will facilitate
emerging sub-THz applications such as super-resolution sensing
and positioning for future smart factories.
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140 GHz Urban Microcell Propagation Measurements for Spatial Consistency Modeling
Abstract—Sub-Terahertz frequencies (frequencies above 100
GHz) have the potential to satisfy the unprecedented demand on
data rate on the order of hundreds of Gbps for sixth-generation
(6G) wireless communications and beyond. Accurate beam tracking
and rapid beam selection are increasingly important since
antenna arrays with more elements generate narrower beams
to compensate for additional path loss within the first meter of
propagation distance at sub-THz frequencies. Realistic channel
models for above 100 GHz are needed, and should include spatial
consistency to model the spatial and temporal channel evolution
along the user trajectory. This paper introduces recent outdoor
urban microcell (UMi) propagation measurements at 142 GHz
along a 39 m 12 m rectangular route (102 m long), where
each consecutive and adjacent receiver location is 3 m apart
from each other. The measured power delay profiles and angular
power spectrum at each receiver location are used to study spatial
autocorrelation properties of various channel parameters such as
shadow fading, delay spread, and angular spread along the track.
Compared to the correlation distances reported in the 3GPP TR
38.901 for frequencies below 100 GHz, the measured correlation
distance of shadow fading at 142 GHz (3.8 m) is much shorter
than the 10-13 m as specified in 3GPP; the measured correlation
distances of delay spread and angular spread at 142 GHz (both 12
m) are comparable to the 7-10 m as specified in 3GPP. This result
may guide the development of a statistical spatially consistent
channel model for frequencies above 100 GHz in the UMi street
canyon environment.
Index Terms—Terahertz; Spatial Consistency; Channel Measurement;
Channel Modeling; 140 GHz; 142 GHz; 5G; 6G
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- Award ID(s):
- 1909206
- NSF-PAR ID:
- 10309423
- Date Published:
- Journal Name:
- IEEE International Conference on Communications
- ISSN:
- 1550-3607
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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