Patent ID: 7085456

Claim:
A branching unit for interconnecting at least three undersea optical transmission cables, said branching unit comprising: a branching device including: a first pressure vessel adapted for use in an undersea environment; first and second ports located in the first pressure vessel for receiving first and second undersea, electrically powered, optical transmission cables; a third port located in the first pressure vessel for receiving a third, electrically unpowered, optical transmission cable; an optical and electrical isolating unit including: a second pressure vessel adapted for use in an undersea environment; fourth and fifth ports located in the second pressure vessel for receiving a fourth undersea, electrically powered, optical transmission cable and a fifth electrically powered transmission cable, respectively; a sixth port located in the second pressure vessel for receiving an end of said third, electrically unpowered optical transmission cable remote from the third port of the branching device; an electrical power conductor segment located in the second pressure vessel for electrically coupling an electrical power conductor in the fourth cable received in the fourth port to an electrical power conductor in the fifth cable received in the fifth port; and at least one optical fiber segment located in the second pressure vessel optically coupling at least one optical fiber of the third cable to at least one optical fiber of the fourth cable.