The new document covers the new radio standards specifications for the Wi-Fi equipment operating in all the 5GHz frequency bands:
- UNII1 (5150-5250MHz)
- UNII2 (5250-5350MHz)
- UNII2-Extended (5470-5600MHz and 5650-5725MHz)
- UNII3 + ISM (5725-5850MHz)
Here are the updated radio standards specifications:
So what has changed? According to me, two important regulations were added. They are detailed below.
TCP Implementation (UNII2 & UNII2-Extended)
For Wi-Fi devices operating the UNII2 and UNII2-Extended, Industry Canada states that "devices with a maximum e.i.r.p. greater than 500mW shall implement TPC in order to have the capability to operate at least 6dB below the maximum permitted e.i.r.p. of 1W". This information can be important to keep in mind while designing a WLAN.
Higher e.i.r.p. allowed for Point-to-Point devices (UNII3 & ISM)
However the standards stats that "fixed point-to-point devices operating in this band may employ transmitting antennas with directional gain greater than 6dBi without any corresponding reduction in transmitter conducted power".
Here is an example to explain this regulation:
If we use a conducted power of 500mW we will have the following e.i.r.p.: 27dBm (500mW) + 9dBi = 36dBm (4W). This complies with the regulations!
On the right part of the drawing, we are setting up a point-to-point bridge link with an antenna gain of 13dBi; which is also greater than 6dBi. Even though the e.i.r.p. exceed 4W, we are still allowed to use a maximum conducted power of 1W.
I hope this information will be useful for some of you.
Written by François Vergès