How to config 951G-2HnD AP router for support wireless N 300

Dear All

My config ::
Internet → ADSL bridge mode → 951G-2HnD router mode (PPPoE) share AP via Wireless

/interface wireless> print
Flags: X - disabled, R - running
0 R name=“wlan1” mtu=1500 mac-address=00:0C:42:B7:xx:xx arp=enabled
interface-type=Atheros AR9300 mode=ap-bridge ssid=“wifi1”
frequency=2457 band=2ghz-b/g/n channel-width=20/40mhz-ht-above
scan-list=default wireless-protocol=802.11 wds-mode=disabled
wds-default-bridge=none wds-ignore-ssid=no bridge-mode=enabled
default-authentication=no default-forwarding=no default-ap-tx-limit=0
default-client-tx-limit=0 hide-ssid=no security-profile=default
compression=no

I tested connect via Laptop Wireless N (300)
→ Connection speed is 1xx Mbps/1xx Mbps
→ Test Copy file speed is 4 - 8 MBps (Maximum Speed 's N draft Only)


How to config 951G-2HnD wireless interface support wireless N 300?

Best regards,
9Toy

use ht below for 2457 frequency