6G • Spectrum
Atmospheric Windows
Low-Loss Transmission Windows at 140, 220, and 340 GHz
Specific valleys in the atmospheric molecular absorption spectrum where wireless signals propagate with minimal attenuation over long distances.
Technical Explanation
While terahertz spectrum suffers from molecular absorption spikes, it also features broad 'atmospheric windows'—valleys where absorption drops to manageable levels (less than 1-2 dB/km). 6G systems target these specific windows: Window 1 (130-175 GHz), Window 2 (200-250 GHz), and Window 3 (300-350 GHz). By centering wideband carriers within these windows, operators achieve multi-kilometer transmission distances identical to legacy millimeter waves.
Key Functions
- Targeting clean atmospheric transmission valleys with minimal molecular water vapor loss
- Window 1 (130-175 GHz) supporting primary metropolitan 6G micro-cells and backhaul
- Window 2 (200-250 GHz) delivering extreme capacity for dense campus and venue deployments
- Window 3 (300-350 GHz) enabling initial commercial terabit-rate point-to-point links
- Maximal spectral efficiency achieved by centering super-wideband carriers in low-loss troughs
Specifications
ITU-R Recommendation P.676, IEEE Microwave and Wireless Components Letters
Interfaces
Atmo-Window-TableCarrier-Center-Bus
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