60 GHz
Understanding 60 GHz Technology
The 60 GHz band is unique among RF frequencies because of the atmospheric oxygen absorption peak. Oxygen molecules resonate at 60 GHz, absorbing electromagnetic energy and limiting propagation distance. While this seems like a disadvantage, it actually enables several benefits: natural security (signals do not travel far enough to be intercepted), interference isolation (neighboring links do not interfere), and spectrum reuse (the same frequencies can be used in close proximity).
Applications
- WiGig (802.11ad/ay): Multi-gigabit wireless networking for indoor environments. Up to 8.085 Gbps with 802.11ay (channel bonding).
- Point-to-point backhaul: Short-range (< 1 km) high-capacity links for 5G small cell backhaul.
- Wireless VR/AR: Low-latency, high-bandwidth links for untethered virtual reality headsets.
- Radar sensing: Gesture recognition, presence detection, and vital signs monitoring.
Available bandwidth: up to 14 GHz (57-71 GHz)
Free-space path loss at 60 GHz, 10m: 88 dB
Wavelength: 5 mm
Frequently Asked Questions
Why does 60 GHz have high atmospheric absorption?
Oxygen molecules have a resonant absorption peak centered at 60 GHz. The magnetic dipole moment of O2 molecules causes them to absorb electromagnetic energy at this frequency, resulting in approximately 15 dB of attenuation per kilometer in addition to normal free-space path loss.
What is the range of 60 GHz systems?
Typical indoor range is 10-30 meters. Outdoor point-to-point links can extend to about 1 km with high-gain antennas, though the link budget must account for 15 dB/km of oxygen absorption in addition to free-space path loss and rain attenuation.
Is 60 GHz the same as V-Band?
V-Band covers 40-75 GHz, so 60 GHz falls within V-Band. However, 60 GHz typically refers specifically to the unlicensed spectrum around 57-71 GHz used for WiGig and short-range communications.