How can I tell if I'm on 4G?

Hi everybody,

I know this seems like a relatively stupid question, but I'm not having any luck in finding the answer on my own.

This is conerning an iPad 3rd Generation, Retina Display 64GB, black, AT&T iPad. We are paying the monthly fee to AT&T, and we just received the normal monthly renewal notice. I can confirm that we are paying for LTE service because in our monthly statement, it says this:

"Your auto-renew of 250 MB of data for 30 days - LTE was successful."

So I know that we are paying for the service.

However, all it ever says in the upper-left corner of the iPad is "AT&T". It never says 4G and it never says LTE. We live in a large metro area with 4G/LTE service everywhere. We live in a location that is covered by the AT&T map that shows 4G/LTE is available all over our area, including where we live. I have friends who have the Verizon version of the same ipad that we have, and theirs always says "LTE" in the upper-left corner.

Is there something wrong with our iPad? How are we supposed to know if we have 4G/LTE service or not if it does not display on the iPad? Also, am I using the correct term? Is it called 4G or is it called LTE when referring to an AT&T iPad.

Thanks!!

PS: We are running iOS 6, and we just updated to iOS 6.1 with the same result.