Sixth-generation wireless networks will aggregate higher-than-ever mobile traffic into ultra-high capacity backhaul links, which could be deployed on the largely untapped spectrum above 100 GHz. Current regulations however prevent the allocation of large contiguous bands for communications at these frequencies, since several narrow bands are reserved to protect passive sensing services. These include radio astronomy and Earth exploration satellites using sensors that suffer from harmful interference from active transmitters. Here we show that active and passive spectrum sharing above 100 GHz is feasible by introducing and experimentally evaluating a real-time, dual-band backhaul prototype that tracks the presence of passive users (in this case the NASA satellite Aura) and avoids interference by automatically switching bands (123.5–140 GHz and 210–225 GHz). Our system enables wide-band transmissions in the above-100-GHz spectrum, while avoiding harmful interference to satellite systems, paving the way for innovative spectrum policy and technologies in these crucial bands.
Terahertz Wireless Communications: Co-Sharing for Terrestrial and Satellite Systems Above 100 GHz
Abstract—This letter demonstrates how spectrum up to 1 THz
will support mobile communications beyond 5G in the coming
decades. Results of rooftop surrogate satellite/tower base station
measurements at 140 GHz show the natural isolation between
terrestrial networks and surrogate satellite systems, as well as
between terrestrial mobile users and co-channel fixed backhaul
links. These first-of-their-kind measurements and accompanying
analysis show that by keeping the energy radiated by terrestrial
emitters on the horizon (e.g., elevation angles g.t. 15 deg), there will
not likely be interference in the same or adjacent bands between
passive satellite sensors and terrestrial terminals, or between
mobile links and terrestrial backhaul links at frequencies above
100 GHz.
Index Terms—Mmwave, terahertz, spectrum sharing and coexistence,
satellite, OOBE, interference mitigation.
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- PAR ID:
- 10309449
- Date Published:
- Journal Name:
- IEEE communications letters
- Volume:
- 25
- Issue:
- 10
- ISSN:
- 1089-7798
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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