Cocoon only works on the 2.4GHz band, so you won't be able to connect using 5GHz.
We have designed Cocoon to function at a very high quality, but at the lower spectrum. This means that it can cope with being located further away from your router, whilst overcoming the obstacles of the home environment.
If you do have a dual-band router but you only have one network name, then you don't need to worry, it will connect to the 2.4GHz band.
If you have two network names, you will need to make sure your smartphone is set it to the 2.4GHz network when you set up your Cocoon for the first time.