How Far should be the PCell and Scell? Can a same Physical eNodeB can handle all (Pcell and Scells)?

Question

Is this a valid CA configuration?

Answer 1

One physical eNodeB can support multi cells of same carrier frequency or different carrier frequencies.
LTE advanced has the concept of primary cell and secondary cells. Primary cell has one carrier frequency and second cell belongs to another carrier frequency. These primary and secondary cells can be created within the same band or inter-band.

Now, answer of your question. Primary and Secondary cells can be co-located.