Subspace radio works using the same technology as the Warp drive, even though the drive was developped over a century earlier. Subspace radio is a signal, similar to conventional 20th-century Terran radio or television. The sound waves are emmited in a subspace field, and because these particles weigh much less than a starship, they can travel at nearly sixty times faster than any ship (Warp Speed 9.9997). The signals can carry audio, visual, and textual transmissions.

he problem with subspace radio is that, unlike a starship, there is no constant source of energy. Without energy, the subspace field will degrade and the radio transmission will fall back to below-light speed. To solve this, Starfleet established a network of subspace relay stations that amplify, reroute, and rebroadcast subspace signals.

On-board Starfleet vessels, personnel use combadges to communicate. Combadges, descendant of the original Enterprise's communicator, are integrated into Starfleet insignia and allow audio communication. They also include subspace beacons, which can be used to locate personnel and allow for off-board communication back to the ship.

Combadges also have integrated universal translators. These allow for real-time, two-way communication by reading and comparing brain-waves, then translating that concept. Translation software was installed on the U.S.S. Enterprise-D's and Voyager's computers. Smaller versions of the translators can fit in the outer ear, but these devices are known to be less reliable.