Are there any spare pairs between the gate opener and the house?

I have used telephone cable pairs to open the gate from the house many times. If you have enough pairs you can do just about anything from the house that you can from the keypad.

Example: If you only have one pair between the opener and the house you can put it on a momentary switch and connect it to the RTE leads in the opener. Pressing the switch will open the gate for the amount of time set in the opener.

Also, many openers have wireless remote ability just like garage door openers if the distance isn't too far.