[show abstract][hide abstract] ABSTRACT: We discuss options for upgrading coarse wavelength-division multiplexed (CWDM) optical access links over standard single-mode fiber (SSMF) by increasing per-channel data rates from 2.5 to 10 Gb/s. We identify electronic equalization and forward error correction (FEC) as the enabling technologies to overcome the dispersion limit of SSMF. In addition, we show how FEC enhances the tolerance to in-band crosstalk, and paves the way toward fully bidirectional CWDM transmission. Due to the lack of CWDM sources rated for 10-Gb/s operation, we demonstrate full-spectrum (1310 to 1610 nm) 10-Gb/s CWDM transmission over standard-dispersion fiber using uncooled, directly modulated lasers specified for 2.5 Gb/s. All 16 CWDM channels could be transmitted over more than 40 km, yielding a capacity-times-distance product of 6.4 Tb/s/km. The longest transmission distance (80 km) was achieved at 1610 nm, equivalent to 1600 ps/nm of chromatic dispersion.
[show abstract][hide abstract] ABSTRACT: We integrated a wavelength-selective cross-connect, de-interleaver, interleaver, power combiner, and variable attenuators on one silica waveguide chip and a band demultiplexer, band multiplexer, and optical monitor on another. These two chips are used to create an eight-channel add-drop node that is expandable up to 80 channels with minimal traffic interruption by adding more of these chips.
[show abstract][hide abstract] ABSTRACT: Uncooled 2.5-Gb/s directly modulated lasers are used to demonstrate a coarse wavelength-division-multiplexed (CWDM) transmission capacity of 160 Gb/s. All 16 CWDM channels, modulated at 10 Gb/s, are simultaneously transmitted over 40 km of uncompensated low-water-peak nonzero dispersion fiber. Operation with bit-error ratio BER<1E-9 is demonstrated for all 16 channels from room temperature to at least 65°C.
[show abstract][hide abstract] ABSTRACT: We demonstrate significant improvement in the measured bit-error rates of 40-Gb/s signals distorted after passing through a saturated semiconductor optical amplifier (SOA) by using a simple colorless general optical equalizer. The optical equalizer reduces the overshoots arising from the nonlinear gain dynamics of the SOA and improves the opening of the eye. We study the improvement in receiver sensitivity by using the equalizer while varying the optical power and wavelength at the input of the SOA.
[show abstract][hide abstract] ABSTRACT: We present a simple, silica waveguide optical equalizer that significantly mitigates intersymbol interference (ISI) impairments for many wavelength-division multiplexed (WDM) channels simultaneously. We study the mitigation of ISI arising from band-limited transmitters, narrow-band optical filtering, chromatic dispersion, and polarization-mode dispersion (PMD). We demonstrate significant improvements, both single- and multichannel, at 40 Gb/s with a single, potentially set-and-forget device.
[show abstract][hide abstract] ABSTRACT: A 16-channel 100-GHz-spacing wavelength selective cross connect is demonstrated using a combination of planar waveguides and MEMS piston-mirrors. Interswitch crosstalk is eliminated and switching speed is an order of magnitude faster than typical thermooptic switches. The power consumption is smaller than one microwatt per switch. An extinction ratio of 20 dB and an insertion loss of 10.6 dB are demonstrated.
[show abstract][hide abstract] ABSTRACT: We demonstrate that a simple general optical equalizer permits the generation of 42.7-Gb/s nonreturn-to-zero data from an 8-GHz bandwidth LiNbO/sub 3/ modulator. The sensitivity at 10/sup -9/ bit-error ratio is only 1 dB poorer than using a 36-GHz bandwith modulator. Since the equalizer can act on many channels simultaneously and be used in a set-and-forget mode, we can potentially reduce the cost of 40-Gb/s transmitters.
[show abstract][hide abstract] ABSTRACT: We demonstrate six-channel 160-Gb/s wavelength-division-multiplexed transmission over 20 100-km spans of nonzero-dispersion fiber, with a spectral efficiency of 0.53 b/s/Hz. We achieve this result using optical-time-division multiplexing with polarization bit interleaving and return-to-zero differential-phase-shift-keying modulation format. We also operate at 170.6 Gb/s per channel to emulate the use of forward error correction.
[show abstract][hide abstract] ABSTRACT: A novel technique for monitoring the alignment status between the pulse carver and data modulator for return-to-zero differential phase-shift keying systems is proposed and demonstrated. The proposed technique utilizes a polarization-maintaining fiber, polarizer, and power meter. Both the simulation and measurement results show that the proposed technique can monitor the bit-error-rate degradation caused by timing misalignment between the pulse carver and data modulator.
[show abstract][hide abstract] ABSTRACT: We present a widely tunable laser consisting of a semiconductor optical amplifier (SOA) glued directly to a silica waveguide grating router, that can be packaged without submicrometer alignments, air gaps, or SOA vertical spot-size conversion. However, issues regarding thermooptic power consumption and modal stability remain to be solved.
[show abstract][hide abstract] ABSTRACT: We demonstrate a colorless thermooptic-lens-based tunable dispersion compensator integrated with a tunable optical noise filter. The free-spectral range is 200 GHz, the tuning range is /spl plusmn/200 ps/nm, the transmissivity 3-dB bandwidth is >40 GHz, and the linear group delay bandwidth is >48 GHz.
[show abstract][hide abstract] ABSTRACT: We present a novel band demultiplexer design for planar lightwave circuits. It consists of two perfectly sampled waveguide grating routers connected by sets of equal-path-length waveguides separated on one side. Its advantages are compactness, sharp passband corners, and a lack of chromatic dispersion.
[show abstract][hide abstract] ABSTRACT: A fully packaged 40-channel 100-GHz-spacing full-coupler-type synchronized-gratings multiplexer with a 1-dB bandwidth >57 GHz, total adjacent crosstalk /spl plusmn/35 GHz around the ITU grid <-18 dB, and loss <3.5 dB for all channels is presented.
[show abstract][hide abstract] ABSTRACT: The authors demonstrate an integrated add-drop filter with true reconfigurability. It can drop any combination of eight wavelengths to any of eight drop ports, with less than 7 dB loss. Its features are suitable for mass production: use of standard silica waveguide technology, double-rejection switching and filtering for all paths, compactness, and power-efficient thermooptic switching.
[show abstract][hide abstract] ABSTRACT: We present a simple silica waveguide optical equalizer that significantly mitigates intersymbol interference impairments for many WDM channels simultaneously. We demonstrate dramatic multichannel improvements at 40 Gb/s with a single, set-and-forget device.
[show abstract][hide abstract] ABSTRACT: We integrated a cross-connect-type add-drop, de-interleaver, interleaver, combiner, and variable attenuators on one silica waveguide chip and a band demux, band mux, and optical monitor on another to create a potentially low-startup-cost node.
[show abstract][hide abstract] ABSTRACT: Tunable dispersion compensators for 10 and 40 Gb/s signals using planar waveguide ring-resonator allpass filters are reviewed. Recent work using tunable ring-resonators as building blocks for PMD emulation, compensation and monitoring are also discussed.
Lasers and Electro-Optics Society, 2002. LEOS 2002. The 15th Annual Meeting of the IEEE; 12/2002
[show abstract][hide abstract] ABSTRACT: A 16-channel wavelength selective cross-connect is demonstrated using planar waveguides and MEMS piston-mirrors. Compared to thermooptic switching, inter-switch crosstalk and power consumption are eliminated
Optical Communication, 2002. ECOC 2002. 28th European Conference on; 10/2002
[show abstract][hide abstract] ABSTRACT: We integrate an improved colorless thermooptic-lens-based tunable dispersion compensator (tuning range of plusmn160 ps/nm) with a tunable amplified spontaneous emission filter on a single silica waveguide chip. We demonstrate fast automatic adjustment of the compensator
Optical Communication, 2002. ECOC 2002. 28th European Conference on; 10/2002
[show abstract][hide abstract] ABSTRACT: Evaluation of the system performance degraded by first-order
polarisation-mode dispersion (PMD) for non-return-to-zero (NRZ) or
return-to-zero (RZ) differential phase-shift-keying (DPSK) signals is
presented. The PMD-induced power penalties were measured with a PMD
emulator for an optically preamplified receiver. The results show that
the PMD sensitivities of DPSK signals are comparable with on-off keying