Communications
Coast Guard radio stations cover a wide geographical area using very high frequency, high frequency, and medium frequency radios. There are eight major radio stations covering long-range transmissions and an extensive network of VHF radio stations along the nation's coastline and inland rivers.
The current communication system is being replaced by Rescue 21. Rescue 21 is an advanced maritime command, control, and communications (C3) system.
The OMEGA navigation system and the LORAN-C transmitters outside the USA were run until 1994 also by the United States Coast Guard, and LORAN-C transmitters within the US were decommissioned on June 1st, 2010, with the exception of 5 CONUS LORAN-C stations that continue to be manned due to international agreements.
Read more about this topic: Equipment Of The United States Coast Guard