Abstract: A submarine optical gain equalizer installed on a submarine optical transmission cable 5. The submarine optical gain equalizer comprises a pressure housing 1, in which an optical gain equalizer and n through-fibers are installed. Input and output ports of the optical gain equalizer and the through-fibers are formed in the outside of the pressure housing. The submarine optical gain equalizer equalizes levels of signal light having wavelengths different each other caused by optical fiber amplifiers. In general, one submarine optical gain equalizer is installed for 40 optical fiber amplifiers on a submarine optical cable.

Abstract: A method of decoding a bitstream having an embedded clock, where the clock reference data is recovered from the bit stream. The clock reference data is combined, typically subtracted, from the system time clock to generate a result. This result is input to a pulse width modulator to form a pulse train, which is used to generate an input to a timing device.

Abstract: A three-level DC-to-DC converter is provided having zero-voltage and zero-current switching (ZVZCS). A flying capacitor is provided on the primary side of the converter to achieve zero voltage switching (ZVS). In addition, during freewheeling (i.e., when no power is being transferred from the primary side to the secondary side), an auxiliary power source is provided to eliminate the circulating energy and to achieve zero current switching (ZCS) for the commutation switches.