If you have radios and a command base, you should be reporting in regularly - the only exception being if you're surrounded by enemies with the means to detect your signals. Yet it's amazing how often operations teams in fiction or in gaming don't report in, even when radio silence is not really needed. The feeling of autonomy adds to the drama of course, and people have come to expect that over years of watching TV and movies.

But try inverting it. Give your PCs some mission, and require them to report in regularly. The command base might be supportive, or potentially interfering, or offer suggestions or orders which are not optimal under the field circumstances. How the PCs react to such communication can lead to interesting roleplaying situations.

Transcript

Han: I told you it was gonna work. No problem.
Leia: Uh huh. They let us through.
C-3PO: So now what?
R2-D2: Same plan. Infiltrate the Peace Moon and take it over. The fact they know we're coming doesn't make it any harder.
[SFX]: < nip-jewhree dip-deep boot-zibuzz bebedooby-bing kibuzz zizang doing dip-deep doosquee ting zi-zing >
GM: Your ship is heading towards the forest moon of Endor.
Luke: They sent us the wrong flight path.
Chewbacca: We should report this. Rebel command, come in.
Admiral Ackbar: {over radio} Admiral Ackbar here, how goes the subterfuge?
Chewbacca: We gave them an obviously fake code, and now they're diverting us to the forest moon.
Admiral Ackbar: Hmmm. Land with caution.
Leia: Don't you think it's a trap?
Admiral Ackbar: I wouldn't have used that word myself.