The Unlicensed National Information Infrastructure (U-NII) radio band is part of the radio frequency spectrum used by IEEE-802.11a devices and by many wireless ISPs. It operates over three ranges:
- U-NII Low: 5.15-5.25 GHz. Regulations require use of an integrated antenna. Power limited to 50mW[1]
- U-NII Mid: 5.25-5.35 GHz. Regulations allow for a user-installable antenna, subject to Dynamic Frequency Selection (DFS, or radar avoidance)[2]. Power limited to 250mW[1]
- U-NII Worldwide: 5.47-5.725 GHz. Both outdoor and indoor use, subject to Dynamic Frequency Selection (DFS, or radar avoidance)[2]. Power limited to 250mW[1]. This spectrum was added by the FCC in 2003 to "align the frequency bands used by U-NII devices in the United States with bands in other parts of the world"[2].
- U-NII Upper: 5.725 to 5.825 GHz. Sometimes referred to as U-NII / ISM due to overlap with the ISM band. Regulations allow for a user-installable antenna. Power limited to 1W[1]
Wireless ISPs generally use 5.725-5.825 GHz.
U-NII is an FCC regulatory domain for 5- GHz wireless devices. U-NII power limits are defined by the United States CFR Title 47 (Telecommunication), Part 15 - Radio Frequency Devices, Subpart E - Unlicensed National Information Infrastructure Devices, Paragraph 15.407 - General technical requirements. Regulatory use in individual countries may differ.
The European HiperLAN standard operates in the U-NII band.
Sources
See also
References
External links
- In the USA, CFR Title 47 Part 15 (revised in 2005) describes the regulation of the U-NII bands.
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