How does one use one shared iAd banner using a Navigational Controller? iPhone/iPad

Basically I have an app that involves a navigation controller that moves between ta开发者_StackOverflow中文版ble views and scroll views. I wish to place iAds under the navigation bar but before the content of the page.

I assumed that in the mainwindow_iphone.xib I could just move down the view down from the navigation bar and have the app delegate handle the ads but apparently you cannot separate the navigational bar like this.

How would I go about implementing this? I would prefer to avoid having a separate banner load on each page.

If anyone needs anymore information from me, feel free to ask!

Thank you.