www.WirelessCommunication.NL Chapter: Wireless Channels

Radio Propagation at 60 GHz

Frequencies around 60 GHz experience significant absorption by Oxigen. At 58 GHz the attenuation is about 12 dB/km. This property can be used as an advantage in interference-limited radio networks.

Indoor Propagation

The 60 GHz band can be a good candidate for indoor wireless office communication, once RF components and modules become more widely available. Indoor rms delay spreads presumably are on the order of 15 to 50 nsec. Typical delay profiles show

• a dominant line-of-sight
• a collection of early reflections with a constant delay profile between 0 and some instant tau.
• an exponential decay beyond tau.

For 60 GHz in-office propagation, tau is about 50 nsec. Oxigen attenuation is not noticable for such short-range transmission.

Severe attenuation occurs when signals have to penetrate through glass or wood. This helps to confine cell areas.

double-glazed windows     3 - 7 dB
concrete wall             20-30  dB

Vehicle-to-Vehicle Propagation

Another application can be car-to-car communication. Communication ranges are short, so typical links will not suffer from oxigen attenuation. However, interference from other links is attenuated, particularly if the transmitters are more than a kilometer away.

Metropolitan Area Networks

For point to point communication between office buildings, 60 GHz is an interesting band.

Wireless Communication © Jean-Paul M.G. Linnartz, 1993, 1996.