WDM-PON Based on Wavelength Locked Fabry-Perot LDs

Abstract

A WDM-PON has been considered as an ultimate solution for access networks. However, there were many technical and practical issues for commercial deployment. These issues were solved with wavelength locked F-P LD and the WDM-PONs employing this optical source were commercialized. These WDM-PON systems have been deployed in Korea, Europe, and US. We reviewed wavelength locking technology and WDM-PON achievements. When we inject spectrum sliced broadband light into an F-P LD, the multimode output is changed to a quasi single mode. Then, we can use the single mode light for WDM signal transmission. The broad spectral gain of the semiconductor gain medium enables a color-free operation of WDM-PON, i.e., an identical ONT can be used for each user. The wavelength locking properties depend on many parameters, especially alignment of injection wavelength to a lasing mode, passband profile of AWG and front facet reflectivity of F-P LD. However, these dependencies can be reduced by proper design of the laser and the injection bandwidth. Thus, WDM-PON systems have been achieved with color-free operation.

Coarsely sliced spectrum wavelength division multiplexing-passive optical networking for remote monitoring systems

“…2 Also, dense wavelength division multiplexing passive optical network ͑DWDM-PON͒ is often too expensive. 3 We propose a PON-like 4,5 low-cost communication architecture utilizing superluminescent light emitting diodes ͑SLEDs͒, coarse wavelength division multiplexers ͑CWDMs͒, and reflective semiconductor amplifiers ͑RSOAs͒. The SLED is used as a low-cost broadband source, 6 while the CWDM multiplexers are used to slice the entire spectrum into four different 20-nm-wide sources for each individual remote site.…”

Equivalent Optical Bandwidth of Reflective Electro-Absorption Modulator Based Optical Source with a Broadband Seed Light for a 2.5 Gb/s and Beyond Signal Transmission

“…In many previous studies, a wavelength-specific optical source has been mainly used as a seeding source for the R-EAM based optical source. However, it has been well known that a broadband light source (BLS) would be a more cost-effective seed source than wavelength-specific sources especially for the colorless wavelength-division multiplexed (WDM)-PON systems [5][6]. Thus, in order to demonstrate the feasibility of the R-EAM based optical source with a BLS seed, we have evaluated the effect of various noises, such as excess intensity noise (EIN) within a BLS, chromatic dispersion of transmission fiber and in-band crosstalk, on the performance of an R-EAM based system [7].…”

Performance Evaluation of Bidirectional Optical Amplifiers for Amplified Passive Optical Network Based on Broadband Light Source Seeded Optical Sources

“…In principle, the in-band crosstalk components would be generated by a double Rayleigh backscattering (DRB) and discrete reflection points within a transmission fiber, and amplified with the gain of bidirectional optical amplifier. In addition, broadband light source (BLS) seeded optical sources, such as a wavelength-locked Fabry-Perot laser diode (FP-LD) and a reflective SOA (RSOA), have been widely used for the cost-effective implementation of hybrid TDM/WDM-PONs or WDM-PONs [6][7], since these sources could provide a colorless operation and a signal modulation/amplification using a single device. Thus, we believe that the maximum gain of bidirectional optical amplifiers should be evaluated properly in order to estimate the maximum reach and splitratio of amplified PONs based on the BLS seeded optical sources.…”