Densify the Network or Adding a New Carrier?

[edgar05]

Hi Experts,

Is there any reason, besides spectrum availability, for which the network densification is preferred before adding a second or third carrier??

It's not clear to me why it's better adding more cells to the network for increasing capacity instead of adding a new carrier to the network.

I know the spectrum is very expensive and it is not always available, but is there any other reason?

Thanks!!