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Title:	Capacity upgrading of scalable passive optical network based on multi-wavelength conversion for access applications
Authors:	Abdulhameed Almabrok Ali Swedan (P60190)
Supervisor:	Mohammad Syuhaimi Ab Rahman, Prof. Ir. Dr.
Keywords:	Universiti Kebangsaan Malaysia -- Dissertations Dissertations, Academic -- Malaysia Passive optical network Multi-wavelength conversion Access applications
Issue Date:	9-Apr-2019
Description:	Optical access networks require more bandwidth to figure out the bottleneck at access area to accommodate number of users and download speed demands. As a result, they have limited use in current network architectures. For these applications to be utilized the new communications' infrastructure must be developed. This research mainly aims to establish an appropriate configuration to provide high-capacity access architecture for broadband networks. This work focuses on characterizing and analyzing the saturated semiconductor optical amplifier (SSOA), and their employment in the 10 G passive optical systems (PON) to provide multi-wavelength conversion at optical network unit (ONU). The configuration is seeking to upgrade the downstream transmission capacity and provide additional bandwidth for end users. The proposed system facilitates the development of 10 GPON to improve the existing systems, besides increasing the number of maximum channels connected to the central office. Two schemes of multi-wavelength conversions (MWC) cross-gain modulation (XGM) and cross phase modulation (XPM) were investigated for short and long-term systems upgrade. Connelly's steady-state numerical model was adopted to investigate the SOA characteristics and evaluate performance under new operating settings. The OptiSystem commercial software is used to simulate the system. The modified SSOA was injected by a combination of an amplified spontaneous emission (ASE) source and a modulated pump to configure wavelength to ASE conversion (WASEC) operation. The design parameters extensively investigated including active region length, confinement factor, and injected current impact on the SSOA output. The results verify that the device provides a gain and noise figure response based on typical profiles, besides the range of 100 nm from 1471 to 1571 nm was passed the test to use as pump wavelength. For the short term improvement, different structures of MWC using continuous wave (CW) sources were demonstrated. The outcomes of 1:4 XPM using two pumps in 1490 and 1550 nm pointed out that the capacity increased from 20 to 100 Gb/s. The new configuration is capable of copying the full data from the modulated original signal pump to the whole ASE based on XGM or XPM SOA. The modulated ASE spectrum is sliced to generate a large number of modulated channels. The obtained channels have been investigated at a data rate of 10 Gb/s. The modulated spectrum of 120 nm was sliced by 0.8 and 0.4 nm spacing, which produce the maximum channels of 116 and 232, within the effective-spectrum of 93 nm from 1522 to 1610 nm. The WASEC structure at 10 Gb/s works well and performs excellently regarding conversion efficiency, waveform shaping, the optical signal to noise ratio, and bit error rate (BER) measurements. The system capacity of 20 km PON has significantly improved from 10 Gb/s to 1.16 and 2.32 Tb/s depending slice spacing. Furthermore, the proposed combination of the WASEC channel distribution device installed inside the ONU together with an optical splitter of 1:64 has been successively validated within the platform of 20 km PON. The results show the capability of all the sliced frequencies to provide the targeted splitting ratio within the pump power range 3 to -3 dBm. Results have confirmed the ability of every single OLT to serve 640 users within the short-term and 7424 or 14848 users for 0.8 and 0.4 nm sliced spacing within the long-term objective each appreciates 156.25 Mb/s bandwidth.,Ph.D.
Pages:	289
Publisher:	UKM, Bangi
Appears in Collections:	Faculty of Engineering and Built Environment / Fakulti Kejuruteraan dan Alam Bina

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