Hi,
I want to use banana pi m3 over a mobile robot. So I sholud use wifi to connect it. But Banana Pi 's own wifi is working very slowly. How can I make it more faster?
When wifi is working slow I tried to use Realtek RTL8192cu with install it’ s driver but wifi didn’ t be active. Can anyone help with it?
Onboard Wi-Fi is pretty limited due to crappy hardware: http://linux-sunxi.org/Banana_Pi_M3#Wi-Fi
External Wi-Fi is not working due to crappy software: https://github.com/BPI-SINOVOIP/BPI-M3-bsp/blob/master/linux-sunxi/arch/arm/configs/sun8iw6p1smp_bpi_defconfig#L1543-L1552
The vendor ‘forgot’ to compile drivers for the most common external Wi-Fi dongles and also lacks the skills to provide linux kernel headers to enable you building ANY device driver on your own. So you can’t compensate from broken onboard Wi-Fi without downloading their whole BSP from Github and compiling an own kernel.
Happy suffering with this great device and this superiour vendor support! 
Thanks for your answer…
I’ m trying to sell it but anyone give an offer … So I’ m trying to use it until I sell it.
are you test our image ,wifi working fine . why not to test it , or you can do and help us , if not ,go away, You has no contribution to this project:sweat_smile:
Which image did you say? I tried lots of image but wifi is working very slowly… 
You have to put BPi M3 as near as possible to the AP. Try to reduce distance to 1m or maybe 50cm! Everything above 3m is known to not work reliably. This is confirmed by all users and denied by @sinovoip again and again
Fixing the problem requires desoldering components so @sinovoip is in the lucky position that if you follow his advices you void your warranty: How to use BPI-M3 wifi extebd antenna slot
if you just want to DIY BPI-M3, use on board wifi antenna, if you want good wifi support ,the best way is to use a External antenna.