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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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This content will become publicly available on December 13, 2026
Over-the-air transmission of Zak-OTFS with spread pilots on the sub-THz communication testbed
Looking towards 6G wireless systems, frequency bands like the sub-terahertz (sub-THz) band (100 GHz - 300 GHz) are gaining traction for their promises of large available swaths of bandwidth to support the ever-growing data demands. However, challenges with harsh channel conditions and hardware non-linearities in the sub-THz band require robust communication techniques with favorable properties, such as good spectral efficiency and low peak-to-average power ratio (PAPR). Recently, OTFS and its variants have garnered significant attention for their performance in severe conditions (like high delay and Doppler), making it a promising candidate for future communications. In this work, we implement Zak-OTFS for the over-the-air experiments with traditional point pilots and the new spread pilots. Notably, we design our spread pilot waveforms with communications and sensing coexisting in the same radio resources. We define the system model and the signal design for integration onto our state-of-the-art sub-THz wireless testbed. We show successful data transmission over-the-air at 140 GHz and 240 GHz in a variety of signal-to-noise ratio (SNR) conditions. In addition, we demonstrate integrated sensing and communications (ISAC) capabilities and show PAPR improvement of over 5 dB with spread pilots compared to point pilots.
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- PAR ID:
- 10656248
- Publisher / Repository:
- IEEE
- Date Published:
- Subject(s) / Keyword(s):
- delay-Doppler, ISAC, OTFS, PAPR, sub-THz, spread-pilots
- Format(s):
- Medium: X
- Location:
- IEEE GLOBECOM, Taipei, Taiwan, December 2025.
- Sponsoring Org:
- National Science Foundation
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