Это радио, такой стабильности как по проводу быть не может. Скорость очень зависит от конечного устройства. Надо смотреть какой битрейт при подключении к роутеру.
iwconfig
eth0 no wireless extensions.
wlan0 IEEE 802.11bgn ESSID:"3500"
Mode:Managed Frequency:2.442 GHz Access Point: 4C:5E:0C:09:3E:7B
Bit Rate=150 Mb/s Tx-Power=15 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=70/70 Signal level=-27 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:806 Missed beacon:0
lo no wireless extensions.
bukass@ubunt:~$ speedtest
Retrieving speedtest.net configuration...
Retrieving speedtest.net server list...
Testing from Omskie kabelnye seti Ltd. (217.25.208.2)...
Selecting best server based on latency...
Hosted by Beeline (Omsk) [2.82 km]: 31.624 ms
Testing download speed........................................
Download: 75.68 Mbit/s
Testing upload speed..................................................
Upload: 49.02 Mbit/s
bukass@ubunt:~$ speedtest
Retrieving speedtest.net configuration...
Retrieving speedtest.net server list...
Testing from Omskie kabelnye seti Ltd. (217.25.208.2)...
Selecting best server based on latency...
Hosted by Beeline (Omsk) [2.82 km]: 22.355 ms
Testing download speed........................................
Download: 79.20 Mbit/s
Testing upload speed..................................................
Upload: 48.65 Mbit/s