Jose A. Lazaro

Scalable Extended Reach PON

Extended reach highly-scalable, fully passive WDM/TDM-PON allows reaching >1000 users along protected 100 km by colorless ONUs, centralized light-generation and control, single-fiber access and remote amplification. ONUs are based on 1.25/2.5/5Gbps-capable RSOA and downstream at 10 Gbps.

10 Gb/s full-duplex bidirectional transmission with RSOA-based ONU using detuned optical filtering and decision feedback equalization

Full-duplex bidirectional transmission at 10 Gb/s is demonstrated for extended wavelength division multiplexed passive optical network (WDM-PON) applications, achieving transmission distances up to 25 km of standard single mode fiber (SSMF) when using a low-bandwidth (approximately 1.2 GHz) reflective semiconductor optical amplifier (RSOA) for signal re-modulation at the optical network unit (ONU). The system is assisted by optimum offset filtering at the optical line terminal (OLT)-receiver and the performance is further improved with the use of decision-feedback equalization (DFE). Chromatic dispersion (CD) and Rayleigh Backscattering (RB) effects are considered and analyzed.

Reach Extension Strategies for Passive Optical Networks [Invited]

We present here the main results for reach extension in passive optical network (PON) technologies. Both passive and active architectures integrating several multiplexing techniques are studied, and they provide promising results for the future generation of optical access networks. Extender boxes based on optical amplification and optical-electrical-optical (OEO) repeaters are evaluated over a standardized gigabit PON (GPON) system. With this architecture, the optical budget of a class B+ access network can be increased so as to achieve a total budget of 65 dB. Furthermore, using the technique of remotely pumped optical amplification on a wavelength division multiplexing/time division multiplexing (WDM/TDM) topology, the optical budget of a class C+ PON tree could be increased by an additional 22 dB amounting to a total budget of 55 dB. These results are promising since they should enable high flexibility on the optical budget to achieve more reach and splitting ratio, which are prerequisites needed for the migration to the next-generation access networks.

WDM transmission at 6-Tbit/s capacity over transatlantic distance, using 42.7-Gb/s differential phase-shift keying without pulse carver

We report the transmission of a record 6 Tbit/s capacity over 6120 km distance, involving channels modulated at 42.7-Gb/s bit-rate with differential phase-shift keying (DPSK). The performance is found similar to DPSK with subsequent pulse carving, namely RZ-DPSK.

Direct 10-Gb/s Modulation of a Single-Section RSOA in PONs With High Optical Budget

We experimentally demonstrate 10-Gb/s operation of a reflective semiconductor optical amplifier (RSOA) for data transmission in passive optical networks, with optical power budgets of up to 28 dB. Besides a passive adaptation for the electrooptical response of the semiconductor device, neither active electronic equalization nor optical offset filtering was applied to enhance the modulation bandwidth of the RSOA. Error-free transmission without using error correcting codes can be obtained even for low RSOA input power values of -20 dBm.

Remotely amplified combined ring-tree dense access network architecture using reflective RSOA-based ONU

Feature Issue on Passive Optical Network Architectures and TechnologiesA highly scalable access architecture achieving high density and featuring resiliency, centralized light-generation control, remote amplification, and colorless optical network unit with reflective semiconductor optical amplifier (RSOA) for upstream modulation is presented and experimentally demonstrated. It is based on a user-single-fiber completely passive outside plant and provides broadband connections to >1000 users distributed along large distances. It is believed to represent an intermediate step toward metro-access convergence and offers flexible configurations covering high- and low-density population areas.

10 Gb/s RSOA transmission by direct duobinary modulation

An ultra low-cost electronic solution to achieve 10 Gb/s transmission by means of passive equalization and duobinary encoding using an RSOA with 1.5 GHz electrical bandwidth is demonstrated.

Remotely Pumped Long-Reach Hybrid PON With Wavelength Reuse in RSOA-Based ONUs

Symmetrical full-duplex transmission in a Passive Optical Network (PON) is demonstrated over a 100 km dual-fiber ring with 1:16 split trees. The customer premises equipment is based on a Reflective Semiconductor Optical Amplifier (RSOA), which reuses the wavelength of the intensity modulated downstream signal for upstream data transmission. A commercial RSOA was used together with optical offset filtering at the upstream receiver to operate at data rates of 5 and 10 Gb/s. Margins of >; 8 dB are left at a data rate of 5 Gb/s, proving that the utilized downstream suppression scheme and therefore the intensity modulation format for both, down- and upstream, is suitable for its application in long-reach hybrid access networks. The signal degradation along the PON and the transmitted pump that features means of remote amplification in its conjunction points between the metro ring and the local trees are discussed and further possibilities for an improvement of the transmission performance are proposed.

Characterization of the Main Semiconductor Laser Static and Dynamic Working Parameters From CW Optical Spectrum Measurements

We present a complete characterization of the work parameters of several types of semiconductor lasers. Static parameters as: power, linewidth and linewidth enhancement factor and also dynamic parameters such as: relaxation oscillations, relative intensity noise and damping rates are calculated using measurements of the optical spectrum of the lasers operated in continuous-wave mode. Methods for the calculation of these parameters are described and applied to the lasers under test by means of a single general setup and a single set of measurements

Demonstration of a Remotely Dual-Pumped Long-Reach PON for Flexible Deployment

We propose and experimentally demonstrate a flexible wavelength division multiplexing/time division multiplexing network architecture for converged metro-access environment. Entire passiveness in the fiber plant is achieved with remote amplification in the signal distribution nodes along the metro ring and in the power splitters of the local access tree. We assist a traditional remote pumping scheme with a distributed pump provided by the optical network units and demonstrate that loss budgets beyond 30 dB can be supported. Data transmission of up to 10 Gb/s is evaluated in different deployment scenarios, reaching from a 78 km long reach rural to a dense 1:128 split/λ urban configuration with field installed fibers, including also worst case resilience configurations.