a question about cpw feed

these are all cpw feed, I wonder what is the different usage of them?why do people always use the second feed in silicon based antenna?thanks.

People use CPW feed for the purpose of better matching over the wider frequency range. The type depends on the application and ease of usage.

I used both and both work well, but i prefer waveport feed because it gives you more grasp on results you can find port impedence, you can deembed your port etc

I am interested to know how to deembed the port's affect when using the port as probe pad? I read some related papers but still puzzled. when simulating, the pad is a part of the antenna,so if deembed it, the result will change.how to deal with that?