Occasionally, when I try to deploy my drone near a base I receive a notification that my drone is being jammed. Is there something nearby I have to disable / destroy to remove the jammer?
Yep, there is a Drone Jammer in the base. Usually in the centre of the base.
If you scout the base with your Binoculars it should still highlight for you, as a radar dish and highlight as 'jammer'.
You can blow it up with explosives, or, if they have a generator, disable that will turn it off also.
It'll look like this.