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We present experimental investigations of the dynamical properties of semiconductor optical amplifiers (SOAs) and their impacts in all-optical signal processing using SOAs. We introduce ultrafast optical signal characterization techniques to fully characterize the gain and phase dynamics of SOAs. We elucidate a consequence of the slow carrier recovery as pattern-dependent phase fluctuation in wavelength conversion of on-off -keyed signals. We also analyze the conversion of the phase fluctuation into amplitude fluctuation limiting the performance of all-optical xor operation. Finally, the performance of all-optical wavelength conversion of differential phase-shift-keyed signals is presented with emphasis on regeneration of the phase information. [ABSTRACT FROM PUBLISHER]

This work presents a high-resolution (13.2 GHz) channel-blocking optical filter, suitable for use as a reconfigurable optical add/drop multiplexer (ROADM), which seamlessly supports data rates from 2.5 to 160 Gb/s. The filter consists of a linear array of 64 MEMS micromirrors and a high-dispersion echelle grating. The demonstrated device had an insertion loss of 9 dB, a loss ripple of 1.2 dB, and a group delay ripple of 15 ps. Data transmission through the device with various mixed data rate scenarios ranging from 2.5 to 160 Gb/s showed negligible penalty, except at 40 Gb/s where a maximum penalty of 1.5 dB was observed due to a phase coherence with the blocker filter ripple. [ABSTRACT FROM PUBLISHER]

We introduce a general concept for the design of all-optical wavelength converters with pulse reformatting functionality. The novel wavelength converters are based on a single semiconductor optical amplifier followed by an optical filter. A microelectromechanical system-based realization is shown and simultaneous 40 Gb/s wavelength conversion, switching and signal format conversion is demonstrated. The new pulse reformatting optical filter device outperforms current schemes with respect to input-power requirements, input-power dynamic range and signal quality. [ABSTRACT FROM PUBLISHER]

This paper analytically and experimentally examines node architectures for wavelength-routing networks, with emphasis on the degree of wavelength conversion provided. Wavelength flexibility simplifies network management and increases network capacity but requires large cross-connects and deployment of wavelength converters (WCs). A simple probabilistic model is used to upper-bound the number of WCs required at a network node, under dynamic traffic load. When provisioned in a shareable pool, with a fixed number of wavelength channels per fiber, the number of WCs required remains low as overall network capacity is scaled up. Motivated by this analysis, experiments demonstrate the feasibility of implementing wavelength-flexible network nodes using large microelectromechanical (MEMS)-based cross-connects and all-optical WCs. In one design, WCs were attached directly to cross-connect output ports, and in another, they were attached in a loop-back fashion to allow sharing. Error-free transmission at 10 Gb/s was demonstrated in both cases. [ABSTRACT FROM PUBLISHER]

This paper describes Si-micromachined two-axis beam-steering micromirrors and their performance in 256 × 256- and 1024 × 1024-port large optical cross-connects (OXCs). The high-reflectivity wavelength-independent mirrors are electrostatically actuated; capable of large, continuous, controlled, dc tilt in any direction at moderate actuation voltages; and allow setting times of a few milliseconds. Packaged two-dimensional (2-D) arrays containing independently addressable identical 256 and 1296 mirrors are used to build fully functional bitrate and wavelength-independent single-stage, low-insertion-loss, single-mode fiber OXC fabrics. [ABSTRACT FROM PUBLISHER]

A single-mode fiber connectorized microelectromechanical systems (MEMS) reflective optical switch attenuator operating in the 1550-nm wavelength region is described. The device consists of an electrostatically actuated gold-coated silicon vane interposed in a fiber gap yielding 0.81-dB minimum insertion loss in the transmit state and high transmission isolation in the reflection state with 2.15-dB minimum return loss. The switch attenuators also work as continuously variable optical attenuators capable of greater than 50-dB dynamic range and can be accurately regulated with a simple feedback control circuit. Switching voltages were in the range of 5-40 V and a switching time of 64 μs was achieved. The MEMS switch can be used in optical subsystems within a wavelength-division-multiplexed (WDM) optical network such as optical power regulators, crossconnects, and add/drop multiplexers. We used a discrete array of 16 switch attenuators to implement a reconfigurable 16-channel 100-GHz spacing WDM drop module of an add/drop multiplexer. Thru-channel extinction was greater than 40 dB and average insertion loss was 21 dB. Both drop-and-transmit of multiple channels (11-18-dB contrast, 14-19-dB insertion loss) and drop-and-detect of single channels (>20-dB adjacent channel rejection, 10-14-dB insertion loss) were demonstrated [ABSTRACT FROM PUBLISHER]

We demonstrate all-optical recognition of a byte pattern embedded in phase-shift-keyed data streaming at 40 Gb/s. We use matched filtering to generate an autocorrelation pulse indicating the pattern matching. Matched filtering is implemented using a reconfigurable silica planar-lightwave-circuit optical delay-line filter. We show excellent discrimination against spurious patterns consistent with the theoretical predictions. [ABSTRACT FROM PUBLISHER]

A reconfigurable 16-channel 100-GHz spacing wavelength-division-multiplexed drop module for use at 1550 nm was demonstrated using silicon microelectromechanical system (MEMS) optical switches and arrayed waveguide grating routers. Through-channel extinction was greater than 40 dB and average insertion loss was 21 dB, Both drop-and-retransmit of multiple channels (11-18 dB contrast, 14-19-dB insertion loss) and drop-and-detect of single channels (>20-dB adjacent channel rejection, 10-14-dB insertion loss) were implemented [ABSTRACT FROM PUBLISHER]