Lightconnect Inc. (Newark, CA) has introduced a MEMS-based dynamic gain equalizer (DGE) for long and ultra-long-haul DWDM systems. The firm's DGE1020 device, when used in a feedback loop, dynamically compensates amplifier gain profiles, thus enabling high signal-to-noise ratio for all channels in optical amplifier systems. Dynamic gain compensation improves system performance, increases system flexibility, and increases the distance between amplifiers in long and ultra-long-haul transmission systems. This device is intended for use with Erbium-doped fiber amplifiers and Raman amplifiers.
The DGE is based on diffractive-MEMS (D-MEMS) technology that reportedly offers several advantages over other MEMS technology. Unlike mirror-based MEMS devices that require large movements of small mirrors, the diffractive MEMS approach requires less than 0.4 microns of motion. Moreover, the high resonant frequencies of the D-MEMS ribbons increase speed by 50 to 500 times over mirror-based MEMS components, while providing an optical platform virtually unaffected by ambient acoustic and seismic disturbances.
Unlike existing static gain flattening filters, which cannot respond to changes in optical networks, diffractive-MEMS-based DGEs respond fast to changes in the optical amplifier gain profile, with low residual ripple after equalization (less than 0.30 dB), even in the steepest portions of the gain profile. The DGEs also consume little power, require no temperature control, and have a small package size (64 by 96 by 16mm). Other features include an operating wavelength range of 1528 to 1570 nm, wavelength step response of 15 dB in 4 nm, and maximum attenuation ofI15 dB.