A branching unit with full or partial broadcast of wavelengths

摘要

A branching unit (1) for optical transmission systems having a coupler (5; 5'). An incoming optical signal carrying a plurality of optical channels (3) is fed into the coupler from a first input port (11). The optical incoming signal has empty channel slots. The coupler (5; 5') adds new channels (6) coming from a branch path (4) to the incoming optical signal by filling the empty channel slots with the new incoming channels (6).