AF11FX Channel Size
- Jonathan Brewer
Ubiquiti’s AF11FX supports 40 or 56 MHz emissions. New Zealand’s channel plan supports 40 or 80 MHz channels. While it’s possible to operate an AF11FX using a 56 MHz emission in an 80 MHz channel, the practice is not allowed by Radio Spectrum Management. It goes against two of their policies - quotes from past deputy registrar Jeff Hicks:
“We have a policy of ensuring that equipment uses the entire 80 MHz bandwidth of the channel.”
“The minimum spectral efficiency requirement of 4 bits/s/Hz for 80 MHz channels in the 11 GHz band”
The second policy can be met by AF11FX if the radio’s operating at 1024QAM, but doesn’t override the first policy.
AF11FX is an inexpensive and inefficient radio & users with high bandwidth requirements should look to a different supplier to go beyond 500 Mbps full-duplex.
AirFibre in an 80 MHz channel on both polarisations nets 687 Mbps full-duplex
Cambium 850C (or Ceragon IP50C) in the same 80 MHz channel on both polarisation nets 1.4-1.7 Gbps
RSM can grant temporary dispensation to use AF11FX at 56 MHz in an 80 MHz channel in some cases - for example if a provider has ordered new equipment for the link that will support the full emission, to replace an existing AF11FX link. Dispensation must be granted in writing before a license modification is allowed.