Subspace relay

A subspace relay, or relay station, was a technical platform designed to receive subspace communications signals and retransmit them to other stations in a larger communications network.

Signals sent in the subspace realm travelled faster-than-light (FTL). Over vast distances, such signals eventually emerged into normal space, dropping to very slow light speed, which made interstellar communications very nearly impossible. Subspace relays solved this problem by receiving FTL subspace communications before they emerged into normal space and retransmitted them in subspace at higher energies, allowing the signal to travel further in subspace, and to arrive at its final destination much faster, than it could without the relay.

The Hirogen relied on a vast communication array network of unknown origins with several relay stations. 

Federation starships, themselves equipped with subspace transmitters relied on a network of subspace relays to boost inter-starship communication over the vast distances of interstellar space. 

In 2369, the Bajoran engineer Neela activated a short range subspace relay she previously placed in the security office aboard Deep Space 9. Combined with her creation, the program ANA, this should help her escape after she assassinated Vedek Bareil Antos by deactivating the promenade's weapon detectors. 

The Cardassian world Loval had a small subspace relay station. 

In the 2370s, the Dominion had an unmanned subspace relay on Callinon VII which the Karemma were told by the Vorta to send messages to. The USS Defiant (2370) transported Jadzia Dax and Miles O'Brien to the subspace relay in 2371 to see where the messages were relayed to. They were detected and a shield was activated around the relay. 

Subraumrelais