recategorized by
1,429 views

1 Answer

Best answer
0 votes
0 votes

The Unlicensed National Information Infrastructure (U-NII)[1][2] radio band is part of the radio frequency spectrum used by IEEE-802.11a devices and by many wireless ISPs. It operates over four ranges:

  • U-NII Low (U-NII-1[3]): 5.150-5.250 GHz. Originally limited to indoor use only. Regulations required use of an integrated antenna, with power limited to 50 mW.[4] Rules changed in 2014 to permit outdoor operation, maximum fixed power 1 watt, maximum fixed EIRP 4 watts (+36 dBm) point-to-multipoint, 200 watts (+53 dBm) point-to-point. [1] However, strict out-of-band emission rules limit practical point-to-point power to lower levels.
  • U-NII Mid (U-NII-2A[3]): 5.250-5.350 GHz. Both outdoor and indoor use, subject to Dynamic Frequency Selection (DFS, or radar avoidance). Regulations allow for a user-installable antenna.[5] Power limited to 250 mW[4]
  • U-NII-2B: 5.350-5.470 GHz. Currently 120MHz of spectrum not allocated by the FCC for unlicensed use.
  • U-NII Worldwide (U-NII-2C / U-NII-2e): 5.470-5.725 GHz. Both outdoor and indoor use, subject to Dynamic Frequency Selection (DFS, or radar avoidance).[5] Power limited to 250 mW.[4] 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".[5] The FCC currently has an interim limitation on operations on channels which overlap the 5600 - 5650 MHz band.[6]
  • U-NII Upper (U-NII-3[7]): 5.725 to 5.850 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[4]

Ans: B

ref: https://en.wikipedia.org/wiki/U-NII

Related questions

0 votes
0 votes
3 answers
1
2 votes
2 votes
3 answers
2
0 votes
0 votes
1 answer
3
0 votes
0 votes
2 answers
4
rishu_darkshadow asked Sep 17, 2017
1,372 views
Match the following :$$\begin{array}{} \hline \text{(i)} & \text{Ethernet} & \text{(a)} & \text{Determinsitic} \\ \hline \text{(ii)} & \text{Token Ring N } & \text{(b)} ...