Outdoor-to-indoor (OtI) signal propagation further challenges the already tight link budgets at millimeter-wave (mmWave). To gain insight into OtI mmWave scenarios at 28GHz, we conducted an extensive measurement campaign consisting of over 2,200 link measurements. In total, 43 OtI scenarios were measured in West Harlem, NewYork City, covering seven highly diverse buildings. The measured OtI path gain can vary by up to40dBforagivenlink distance, and the empirical path gain model for all data shows an average of 30dB excess loss over free space at distances beyond 50m, with an RMSfitting error of 11.7 dB. The type of glass is found to be the single dominant feature for OtI loss, with 20dB observed difference between empirical path gain models for scenarios with low-loss and high-loss glass. The presence of scaffolding, tree foliage, or elevated subwaytracks, as well as difference in floor height are each found to have animpact between 5–10dB. Weshowthatforurbanbuildings with high-loss glass, OtI coverage can support 500Mbps for 90% of indoor user equipment (UEs) with a base station (BS) antenna placed up to 49m away. For buildings with low-loss glass, such as our case study covering multiple classrooms of a public school, data rates over 2.5/1.2 Gbps are possible from a BS 68/175m away from the school building, when a line-of-sight path is available. We expect these results to be useful for the deployment of mmWave networks in dense urban environments as well as the development of relevant scheduling and beam management algorithms.
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Outdoor-to-Indoor 28 GHz Wireless Measurements in Manhattan: Path Loss, Environmental Effects, and 90% Coverage
Outdoor-to-indoor (OtI) signal propagation further challenges the
already tight link budgets at millimeter-wave (mmWave). To gain
insight into OtI mmWave scenarios at 28 GHz, we conducted an
extensive measurement campaign consisting of over 2,200 link measurements. In total, 43 OtI scenarios were measured in West Harlem,
New York City, covering seven highly diverse buildings. The measured OtI path gain can vary by up to 40 dB for a given link distance,
and the empirical path gain model for all data shows an average of
30 dB excess loss over free space at distances beyond 50 m, with an
RMS fitting error of 11.7 dB. The type of glass is found to be the
single dominant feature for OtI loss, with 20 dB observed difference
between empirical path gain models for scenarios with low-loss and
high-loss glass. The presence of scaffolding, tree foliage, or elevated
subway tracks, as well as difference in floor height are each found to
have an impact between 5–10 dB. We show that for urban buildings
with high-loss glass, OtI coverage can support 500 Mbps for 90%
of indoor user equipment (UEs) with a base station (BS) antenna
placed up to 49 m away. For buildings with low-loss glass, such
as our case study covering multiple classrooms of a public school,
data rates over 2.5/1.2 Gbps are possible from a BS 68/175 m away
from the school building, when a line-of-sight path is available. We
expect these results to be useful for the deployment of mmWave
networks in dense urban environments as well as the develop
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- NSF-PAR ID:
- 10346945
- Date Published:
- Journal Name:
- ArXivorg
- ISSN:
- 2331-8422
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Outdoor-to-indoor (OtI) signal propagation further challenges link budgets at millimeter-wave (mmWave). To gain insight into OtI mmWaveat28GHz, we conducted an extensive measurement campaign consisting of over 2,000 link measurements in West Harlem, NewYorkCity, covering seven highly diverse buildings. A path loss model constructed over all links shows an average of 30dB excess loss over free space at distances beyond 50m. We find the type of glass to be the dominant factor in OtI loss, with 20dB observed difference between clustered scenarios with low- and high-loss glass. Other factors, such as difference in floor height, are found to have an impact between 5ś10dB. We show that for urban buildings with high-loss glass, OtI data rates up to 400Mb/s are supported for 90% of indoor users by a base station (BS) up to 49m away. For buildings with low-loss glass, such as our case study covering multiple classrooms of a public school, data rates over 2.8/1.4Gb/s are possible from a BS 68/175m away when a line-of-sight path is available. We expect these results to be useful for the deployment of OtI mmWave networks in dense urban environments and the development of scheduling and beam management algorithms.more » « less
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null (Ed.)This paper provides indoor reflection, scattering, transmission, and large-scale path loss measurements and models, which describe the main propagation mechanisms at millimeter wave and Terahertz frequencies. Channel properties for common building materials (drywall and clear glass) are carefully studied at 28, 73, and 140 GHz using a wideband sliding correlation based channel sounder system with rotatable narrow-beam horn antennas. Reflection coefficient is shown to linearly increase as the incident angle increases, and lower reflection loss (e.g., stronger reflections) are observed as frequencies increase for a given incident angle. Although backscatter from drywall is present at 28, 73, and 140 GHz, smooth surfaces (like drywall) are shown to be modeled as a simple reflected surface, since the scattered power is 20 dB or more below the reflected power over the measured range of frequency and angles. Partition loss tends to increase with frequency, but the amount of loss is material dependent. Both clear glass and drywall are shown to induce a depolarizing effect, which becomes more prominent as frequency increases. Indoor propagation measurements and large-scale indoor path loss models at 140 GHz are provided, revealing similar path loss exponent and shadow fading as observed at 28 and 73 GHz. The measurements and models in this paper can be used for future wireless system design and other applications within buildings for frequencies above 100 GHzmore » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.48550/arXiv.2205.09436
