| Author | Wan, Yueting |
| Call Number | AIT RSPR no.TC-97-4 |
| Subject(s) | Optical communications
|
| Note | A research study submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Advanced Technologies |
| Publisher | Asian Institute of Technology |
| Series Statement | Research studies project report ; no. TC-97-4 |
| Abstract | In recent decades, the nonlinearity of optical fiber has been enthusiastically studied and
applied. Among various applications, all-optical switching devices based on cross phase
modulation in optical fiber are of great interest because of their potential ultra-high-speed
response, high-power density due to their guided-wave structure, and extremely long
interaction length. Among them, the Sagnac-interferometer-based switch, which consists of a
directional coupler with its output ports connected by a nonlinear material, is most promising
because of its inherently balanced interferometer configuration that allows long fiber lengths
of over 1 km. This reduces the switching power while ensuring environmental stability.
In this research report, we reviewed the basic theory of nonlinear cross-phase
modulation and made a brief description of Nonlinear Sagnac Interferometer Switch (NSIS).
Also, the characteristics of NSIS and its applications to Ultra-High-Speed Optical Fiber
Communication Systems were discussed.
Because GVD could not be neglected in most cases, we have to base our studies on
the fundamental equations governing the nonlinear characteristics of fiber loop of NSIS. The
characteristics of the equations were studied and a numerical method, which is called split step
Fourier method was studied and applied. Based on this, we composed a computer program in
FORTRAN language which can be used to numerically solve the equations. Further studies
can be continued with the program. Some numerical results were obtained and relative
analyses were given.
Apart from the verification of some main characteristics of NSIS. We found that for
the case of LNL-Lv , a length of 0.1Lv optical fiber is a good choice for the transmission of a
signal with Gaussian pulse when both the pulse shape and pulse power are concerned during
the transmission period. When only data signals are considered, it is found that the length of
Lv is still a good choice. We also found that any value of probe power, which has a certain
repetition rate or a fixed pulse width and is smaller enough so that the nonlinearity caused by
it may be neglected, may be used to determine the nonlinear influence of a given pump pulse |
| Year | 1997 |
| Corresponding Series Added Entry | Asian Institute of Technology. Research studies project report ; no. TC-97-4 |
| Type | Research Study Project Report (RSPR) |
| School | School of Advanced Technologies (SAT) |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Telecommunications (TC) |
| Chairperson(s) | Zhang, Jian-Guo |
| Examination Committee(s) | Sharma, A. B.;Erke, Tapio |
| Scholarship Donor(s) | Asian Institute of Technology |
| Degree | Research Studies Project Report (M. Eng.) - Asian Institute of Technology, 1997 |