Ruwan Weerasuriya

Generation of frequency symmetric signals from a BPSK input for phase sensitive amplification

We report a novel system for simultaneous carrier recovery and frequency symmetric signals generation from a NRZ-BPSK input by exploiting FWM in HNLF for phase sensitive amplification.

DPSK Signal Regeneration With a Dual-Pump Nondegenerate Phase-Sensitive Amplifier

We demonstrate, for the first time to our knowledge, regeneration of a 42.66-Gb/s differential phase-shift keyed signal using a dual-pump nondegenerate four-wave-mixing-based fiber-optic parametric amplifier. The regenerative performance of the subsystem is characterized in terms of bit-error rate against narrowband and wideband introduced noise. While a strong receiver sensitivity improvement, up to 20 dB, is noticed against narrowband noise, against quasi-random (wideband) noise we observe a regeneration of 2.7 dB.

All-optical phase regeneration of 40Gbit/s DPSK signals in a black-box phase sensitive amplifier

We present a black-box four wave mixing based bit-rate-flexible phase sensitive amplifier and use it in the first demonstration of 40 Gbit/s DPSK phase regeneration.

Novel real-time homodyne coherent receiver using a feed-forward based carrier extraction scheme for phase modulated signals

We report a novel real-time homodyne coherent receiver based on a DPSK optical-electrical-optical (OEO) regenerator used to extract a carrier from carrier-less phase modulated signals based on feed-forward based modulation stripping. The performance of this non-DSP based coherent receiver was evaluated for 10.66 Gbit/s BPSK signals. Self-homodyne coherent detection and homodyne detection with an injection-locked local oscillator laser was demonstrated. The performance was evaluated by measuring the electrical signal-to-noise (SNR) and recording the eye diagrams. Using injection-locking for the LO improves the performance and enables homodyne detection with optical injection-locking to operate with carrier-less BPSK signals without the need for polarization multiplexed pilot-tones.

Field Experiments With a Grooming Switch for OTDM Meshed Networking

Field experiments of 42.7/128.1 Gb/s wavelength-division multiplexed, optical time-division multiplexed (WDM-OTDM) transmultiplexing and all-optical dual-wavelength regeneration at the OTDM rate are presented in this paper. By using the asynchronous retiming scheme, we achieve error-free bufferless data grooming with time-slot interchange capability for OTDM meshed networking. We demonstrate excellent performance from the system, discuss scalability, applicability, and the potential reach of the asynchronous retiming scheme for transparent OTDM-domain interconnection.

Phase locking and carrier extraction schemes for phase sensitive amplification

We demonstrate two schemes which enable simultaneous phase locking, carrier extraction and frequency shifting for use in stand-alone phase sensitive amplifiers. The schemes provide phase locked pumps at appropriate frequency spacing for a number of non-degenerate PSA configurations.

Novel carrier extraction scheme for phase modulated signals using feed-forward based modulation stripping

We report a novel carrier extraction scheme for carrier-less phase modulated signals using feed-forward based modulation stripping. The scheme could be used in various sub-systems which require phase coherent local oscillators such as phase sensitive amplifiers or coherent receivers.

Field trial of WDM-OTDM transmultiplexing employing photonic switch fabric-based buffer-less bit-interleaved data grooming and all-optical regeneration

We report, for the first time, a field trial of a novel 42.7Gbps/128.1Gbps WDM/OTDM grooming node, and confirm node interoperability and the data integrity of asynchronous retiming.

Optical grooming switch with regenerative functionality for transparent interconnection of networks

We demonstrate a regenerative optical grooming switch for buffer-less interconnection of metro/access and metro/core ring networks with switching functionality in time, space and wavelength domain. Key functionalities of the router are the traffic aggregation with time-slot interchanging (TSI) functionality, the WDM-to-ODTM multiplexing and the OTDM-to-WDM demultiplexing of high-speed channel into lower bit-rate tributaries as well as multi-wavelength all-optical 2R regeneration of several higher-speed signals. BER and Q-factor measurements of different switching scenarios show excellent performance with no error floor and Q-factors above 21 dB.

An All-Optical Grooming Switch for Interconnecting Access and Metro Ring Networks [Invited]

A regenerative all-optical grooming switch for interconnecting 130 Gbit/s on-off keying (OOK) metro/core ring and 43 Gbit/s-OOK metro/access ring networks with switching functionality in time, space, and wavelength domains is demonstrated. Key functionalities of the switch are traffic aggregation with time-slot interchanging functionality, optical time division multiplexing (OTDM) to wavelength division multiplexing (WDM) demultiplexing, and multi-wavelength 2R regeneration. Laboratory and field demonstrations show the excellent performance of the new concept with error-free signal transmission and Q-factors above 20 dB.