Which antenna is for receiving?

Hello. With my basebox2 I have one 15dbi omni antenna and one 7dbi omni antenna.

I want to know which SMA/antenna port if for sending, and which is for receiving.

I want to use the 15dbi for receiving for embedded low power devices like my nexus7 and the 7dbi for sending.

This seems to make sense given my current hardware since the basebox2 pushes more wattage in the air, it doesn’t need the 15dbi for sending.

Thanks in advance,

Utopian