Performance Of RSOA-based Wavelength Reused WDM-PON

Traffic patterns change in access networks require new access networks that support high-speed (> 100 Mb/s) bandwidths in each channael for future video services with high-definition TV quality. To minimize the cost of implementing a fiber to the premise (FTTP) solution, a passive optical network (PON) that uses a point-to-multipoint architecture is generally considered to be the best approach. While a TDM-PON appears to be a satisfactory solution for current bandwidth demands, the WDM -PON which provides point-to-point optical connectivity using a dedicated pair of wavelengths per user is widely believed to be the route towards the next generation of PONs. The technology challenge for WDM-PON has been to avoid the need for expensive wavelength selective optical components in each end-users optical network unit(ONU)。And the RSOA-based wavelength re-used WDM-PON scheme is a cost-effective solution. Camparing to other scheme, it only need one transmitter and one wavelength to fulfill the communication between each OUN and the Central Office (CO).In this paper, we will start by reviewing the current legacy methods for access solutions and point out their limitations. In the next section, we introduced the principle and characteristics of the semiconductor optical amplifier (SOA), which is a key device in the wavelength re-used WDM-PON scheme. The typical specification and classification is also included in this section. The following two section focus on the temperature control and power drive principle for the SOA, along with detailed circuits design and debug procedure. Finally, we analyze and compare the characteristics of RSOA-based wavelength re-used WDM-PON which adapts 1.25Gb/s, 2.5Gb/s and 5Gb/s Manchester and NRZ coded downstream signals and 1.25Gb/s NRZ coded upstream signals. The results showed that Manchester coded downstream signals are desirable in the asymmetric down/upstream bit rate, and also more suitable than NRZ coded downstream signals in the symmetric down/upstream bit rate.