I start an Ad campaign and whenever user clicks the Ad banner, he will be redirect to a URL like this:
mysite.com/?utm_source=ad3
Then in my Google Analystics, I defines a goal as:
mysite.com/goal.htm
Then how to associate the ad campaign with the goal so that I can know whether the goal is generated from the ad campaign?
When using manual campaigns utm_source, utm_medium and utm_campaign are required parameters, you should use all 3.
If you go into your traffic source reports you can select the Goal metrics to see how many goals are completed per traffic source. This is automatically done for your correctly manual tagged campaigns.