I have a rb532 running 2.9.19 and I’ve found that my SR5 on a 12db Omni (this is in lab) is only outputting about 18Mbps TCP/UDP traffic yet can receive a full 30-35Mbps TCP/UDP. If I switch the card out to a CM9, I can see 30-35Mbps both ways. Is this a problem with SR5 cards (its fairly new) or do I just have a bad one. I’ve checked antenna and made sure I’m using A (ufl). Any suggestions?
Thanks
Nik
Update:
I’ve found that the speeds only slow down if I set the SR5 to the full 26dbm that i outputs. If I set the tx-power-mode to default it works fine. If I set to tx-power-mode=all-rates-fixed, manual-table,or card rates and tx-power=anything higher then 17, I see the throughput drop. Is this a bug? or is too much power being consumed by the card and the routerboard can’t keep up?
Thanks
On all OFDM cards, the max usable TX power drops as the modulation rates increase- this is to do with linearity in the TX amplifier I believe, which is more critical at high order modulation.
If you have to have 26dbm, exclude the higher modulation speeds and accept lower throughput.
If you must have 36, 48 , 54Mbps modulation, reduce the TX power.
AFAIK there is a table on the SR5 datasheet. I’ve not yet used that card, but we have tested various other brand atheros cards.
Regards
CableFree Solutions