ULTRA-WIDE BANDWIDTH FIBER BASED OPTICAL AMPLIFIER
An ultra-wide bandwidth optical amplifier (10) for the 1550nm optical band divides the 1520nm-1610nm bandwidth into three narrow bandwidths, i.e. C1(1520nm-1541nm), C2(1541nm-1565nm) and L(1565nm-1610nm), and uses three separate erbium doped fiber amplifier blocks (12, 14, 16), configured in parallel relation and individually optimized to separately amplify the respective bandwidth. Multipath interference is controlled by constructing all three amplifier blocks with the same optical transmission length. The C1 and C2 band amplifier blocks (12, 14), which include shorter erbium doped fibers (44, 52) than the L band amplifier block (16), are physically lengthened using lengths of single mode fiber (70, 72) so that the optical transmission path of each amplifier block is generally equal. Amplifier blocks (12, 16) further include delay control devices (74, 76) which selectively delay signals passing through the respective amplifier block (12, 16) to provide fine adjustment to signal recombination.