If you have two different banners on your home page which link to the same page, you can only differentiate them in your analysis by tagging the URL in the banners differently. To do so you need to use Netminers Internal Link URL Generator.
Please note that this tool is only for tagging links on your own website. For example, if you have two different banners on your home page which link to the same page, you can only differentiate them in your analysis by tagging them differently.