You're looking at the difference in code rates between 256QAM 3/4 code rate (MCS8) and 256QAM 5/6 code rate (MCS9)? All things being equal in the same size TDD 40 MHz channel, of course the MCS9 radio will have a greater bps/Hz.
Talking about the bps/Hz for a single stream, the specs for 802.11ac say that an MCS8 channel 40 MHz wide will be 162 to 180 Mbps, while a MCS9 channel 40 MHz wide will be 180 to 200 Mbps. I am not sure the two can be compared directly side by side thanks to the B5's split frequency modes of operation. They can be better compared head to head if you're using a single fixed TDD frequency (like, 5760 center channel). On Thu, Nov 5, 2015 at 10:41 PM, Stefan Englhardt <[email protected]> wrote: > Anyone who have them both running did an unbiased comparison? > > We’ve several B5 links running and are quite happy with them. > > Good 11ac radios in a very neat package. > > > > The AF5x on the other side is a custom designed radio which seems to > > squeeze more mbits out of smaller channels. In a 40MHz Channel I see > > an aggregated thruput of 320 Mbit/s with the B5 with 4ms framesize at > > MCS9 (256QAM). > > Looking at the AF5X (inofficial) link table should do 390 Mbit/s aggregated > > with 2ms framesize. So they promise to do higher bandwidth with lower > > latency in a 40MHz Channel (at smaller channels the difference is higher > > as .ac do only MCS8). > > > > Is the AF5X the better radio with limited spectrum while the B5 can do more > > with enough spectrum available? > > > > I’ve sites where I ran out of spectrum (ETSI) so I plan to put AF5X there. >
