Extremely simple to set up - but simultaneous Dual Band NO

The setup is really super simple, small application provided on CD (Multi-OS) automatically finds the terminal connected to the local network.
Just enter a network name, select a wireless key and the frequency band to be used. (2.4GHz 5GHz OR)

This is the problem:
I'm in a saturated environment where there are multiple wireless terminals 2.4GHz, resulting in low flow or cuts when I turn on my microwave (2.4GHz ^^)
I wish to make the Simultaneous Dual Band:
1) A broadband connection 802.11n 5GHz WiFi on my MacBookPro / iPhone 5 / iPad Retina to avoid interference.
2) Keep the 2.4 GHz band active for devices that do not support the 5GHz band (iPhone 4, 4S, ...)

Now this terminal is not Dual Band, she does not disseminate both on the band of 2.4 and that of 5. It must choose.