Summary: | 碩士 === 國立臺灣師範大學 === 工業教育學系 === 95 === In this thesis, we proposed three different methods to improve the performances of bidirectional hybrid dense wavelength-division-multiplexing (DWDM) for passive optical network (PON) transport system.
First, we proposed a bidirectional hybrid DWDM-PON transport system employing external light injection technique on vertical cavity surface emitting lasers (VCSELs) and distributed feedback laser diodes (DFB LDs). The broadband amplified spontaneous emission (ASE) light source is generated from a 3-stage erbium-doped fiber amplifier (EDFA). The broadband ASE is efficiently divided into four optical channels as injection sources by using DWDM DEMUX. Using an external light injection technique can effectively enhance the frequency response and reduce the driving current of VCSEL. The performance can be raised in our transport system.
Second, we completed a bidirectional hybrid DWDM-PON transport system based on data comparator and amplitude/phase compensator behind receiver. The system of distorted signal was compensated by data comparator and amplitude/phase compensator. Furthermore, the original signal can be continuously feedback in comparator and compensator to correct signal distortion. Thus the system distorted signal can be removed within less time. Therefore, the signal quality can be improved in transport system.
Finally, we employed both of external light injection technique, data comparator and amplitude/phase compensator for bidirectional hybrid DWDM-PON transport system. The experimental results showed that the performances of bit error rate (BER), carrier-to-noise ratio (CNR), composite second order (CSO), and composite triple beat (CTB) were improved over a 40-km standard single-mode fiber (SSMF) transport system.
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