David Wolfson

40-Gb/s all-optical wavelength conversion, regeneration, and demultiplexing in an SOA-based all-active Mach-Zehnder interferometer

All-optical 2R and 3R regeneration techniques are investigated at 40 Gb/s. It is shown that an all-active SOA-based Mach-Zehnder device, employed as a wavelength converter, is capable of improving the OSNR by more than 20 dB at this bit rate, thereby resulting in penalty reduction. Furthermore, simultaneous all-optical wavelength conversion and demultiplexing from 40 to 10 Gb/s is demonstrated showing that the scheme, which also has a 3R regeneration capability, is feasible in a combined OTDM/WDM network.

Novel scheme for simple label-swapping employing XOR logic in an integrated interferometric wavelength converter

We present a novel scheme for all-optical label swapping that relies on logic exclusive-OR (XOR) in an integrated SOA-based Michelson interferometer. The scheme allows simple, efficient and mechanically stable operation, while relaxing the requirements on packet format and simplifying switch management. Furthermore, the label-swapping scheme does not require a guard band between the header and payload to perform alterations in the header. The method, which incorporates simultaneous wavelength conversion, is demonstrated at 10 Gb/s with negligible penalty and a high output signal-to-ASE ratio of /spl sim/35 dB.

Detailed theoretical investigation of the input power dynamic range for gain-clamped semiconductor optical amplifier gates at 10 Gb/s

A detailed theoretical investigation of the input power dynamic range for gain-clamped semiconductor optical amplifier (GC-SOA) gates at 10 Gb/s is presented. We show that although the gain is clamped, the dynamic changes of the carrier distribution in the GC-SOA causes pattern effects on a time scale given by the relaxation frequency of the GC-SOA. Combined with a higher noise figure compared to a conventional SOA, this results in a dynamic range only /spl sim/0.5 dB better than for an optimized SOA gate.

All-optical 2R regeneration at 40 Gbit/s in an SOA-based Mach-Zehnder interferometer

All-optical 2R regeneration in an SOA-based Mach-Zehnder interferometer is demonstrated at 40 Gbit/s. The regenerative capabilities combined with an input power dynamic range of 16 dB demonstrate the feasibility of this technique at very high bit rates.

Optical label swapping using payload envelope detection circuits

Optical label swapping of 10-Gb/s nonreturn-to-zero (NRZ) labels attached to 40-Gb/s return-to-zero payloads is demonstrated using payload envelope detection (PED) circuits based on 40-Gb/s clock recovery with nanosecond locking time. The circuits generate a digital envelope signal representing the payload location without having to process the 40-Gb/s data. The low-frequency PED signal, which is generated from the recovered 40-GHz packet clock by a radio-frequency mixer, can be utilized to erase/rewrite the label through traveling-wave electroabsorption modulators. This approach does not require active timing control to erase the label. Nearly penalty-free rewriting of a new 10-Gb/s NRZ label was demonstrated.

Experimental investigation at 10 Gb/s of the noise suppression capabilities in a pass-through configuration in SOA-based interferometric structures

We experimentally investigate a pass-through scheme for all-optical noise suppression in a SOA-based interferometric structure at 10 Gb/s. An input power dynamic range of /spl sim/8 dB as well as a noise suppression capability of /spl sim/4.5 dB has been demonstrated. Furthermore, the transmission properties have been investigated showing a small pre-amplified penalty of /spl sim/0.3 dB after transmission over 31 km of standard single mode fiber.

Experimental and theoretical investigation of the regenerative capabilities of electrooptic and all-optical interferometric wavelength converters

An experimental and theoretical investigation of the regenerative capabilities of electrooptic (E/O) and all-optical (A/O) interferometric wavelength converters is presented. We show that both the E/O and A/O regeneration scheme exhibit a 5-dB noise suppression capability. Furthermore, we demonstrate that by cascading two A/O-converters after an erbium-doped fiber amplifier (EDFA), the performance is further improved resulting in a total noise suppression of 8 dB. Our detailed model, which accounts for the redistribution of a signal in the converters, shows good agreement with the experiments and predicts a significant increase in the number of EDFAs that can be cascaded with interferometric wavelength converters in the link.

Synchronizing optical data and electrical control planes in asynchronous optical packet switches

We experimentally demonstrate the use of optical payload envelope detection in a 40 Gbit/s asynchronous optical packet switch to synchronize the optical data and electrical control planes. Measurements show 100% envelope recovery over an 8.5 dB packet power dynamic range.

Burst mode 10 Gbps optical header recovery and lookup processing for asynchronous variable-length 40 Gbps optical packet switching

We demonstrate 10 Gbps asynchronous optical header recovery with less than 20 bits lock time and over 380 bits hold time after the label end. Layer-1(BER) and Layer-2(Header Loss) results are presented for the first time

Suppression of interferometric crosstalk and ASE noise using a polarization multiplexing technique and an SOA

Noise suppression at 10 Gbit/s and 20 Gbit/s is demonstrated using a gain saturated semiconductor optical amplifier (SOA) and a polarization multiplexing technique, where no impairments like waveform distortion and extinction ratio degradation caused by the gain saturation of the SOA appear. Moreover, the method is bit rate transparent and the input power dynamic range is very large. Furthermore, the SOA can provide a high gain.