Abstract: A long-distance DWDM lightwave transmission system operating in the 2000 nm wavelength region is proposed that is based on the utilization of hollow core fiber configured to exhibit low loss (e.g., on the order of 0.02 dB/km) in combination with a hybrid TDFA/HDFA repeater device. Multiple concatenated spans of the combination of the hollow core fiber and hybrid TDFA/HDFA repeater device are able to provide communication over path lengths in excess of 10,000 km without the need for electronic regeneration of the propagating signals. In one case, the hollow core fiber is configured as a double-nested anti-resonant nodeless fiber (DNANF) with the number of nested structures and their various parameters optimized to provide the low loss operation in the 2000 nm region.

Abstract: A long-distance DWDM lightwave transmission system operating in the 2000 nm wavelength region is proposed that is based on the utilization of hollow core fiber configured to exhibit low loss (e.g., on the order of 0.02 dB/km) in combination with a hybrid TDFA/HDFA repeater device. Multiple concatenated spans of the combination of the hollow core fiber and hybrid TDFA/HDFA repeater device are able to provide communication over path lengths in excess of 10,000 km without the need for electronic regeneration of the propagating signals. In one case, the hollow core fiber is configured as a double-nested anti-resonant nodeless fiber (DNANF) with the number of nested structures and their various parameters optimized to provide the low loss operation in the 2000 nm region.

Abstract: A hybrid optical fiber amplifying device is proposed that is based upon a concatenated combination of a section of Tm-doped fiber (TDF) followed by a section of Ho-doped fiber (HDF). The doped fiber sections are configured to be no more than a few meters in length. Using the sections of doped fiber in this order (i.e., TDF followed by HDF) has been found to provide amplification of input signals over a relatively wide wavelength band from about 1725 nm to about 2105 nm (thus exhibiting a useful wideband range of about 380 nm). The use of pump beams operating at several Watts of power have been found to yield multi-Watt output signals. The wideband hybrid device itself may take the form of an amplifier, laser (including a ring laser configuration), or a source of amplified stimulated emission (ASE).

Abstract: An electroabsorption modulator comprises a tandem arrangement of a conventional electroabsorption (EA) modulator element and a phase modulator element. The EA modulator element is driven by the digital data signal and the phase modulator is driven by a chirp tuning control signal, such as the complement of the data signal. By controlling the amplitude and/or bias of the chirp tuning control signal, the frequency chirp of the intensity-modulated output signal from the EA modulator element can be controlled.

Abstract: An electroabsorption modulator comprises a tandem arrangement of a conventional electroabsorption (EA) modulator element and a phase modulator element. The EA modulator element is driven by the digital data signal and the phase modulator is driven by a chirp tuning control signal, such as the complement of the data signal. By controlling the amplitude and/or bias of the chirp tuning control signal, the frequency chirp of the intensity-modulated output signal from the EA modulator element can be controlled.