Augustin Vyukusenge,
University of Bujumbura, Bujumbura, Burundi,

DOI: 10.36724/2664-066X-2021-7-1-33-38

SYNCHROINFO JOURNAL. Volume 7, Number 1 (2021). P. 33-38.


System distortions due to chromatic dispersion (CD), polarization mode dispersion (PMD), laser phase noise and fiber nonlinearities have a significant impact on the performance of high-speed fiber optic networks [1].
In connection with the need to improve the quality of information transmission in high-speed fiber-optic communication systems, coherent detection with a digital signal processing unit is of particular interest. The main goal of the DSP block is to reduce the impact of linear and nonlinear effects that degrade the quality of information transfer. In this direction, the use of adaptive filters with adaptation algorithms for filter coefficients plays an important role. The Constant Modulus Algorithm (CMA) and the Least Mean Square (LMS) method used to compensate for dispersion distortions are presented. The load on transport networks based on fiber-optic transmission systems is increasing at an accelerating rate. This paper discusses the possibility and limitations of increasing the throughput of fiber-optic transmission systems by reducing the distance between carriers. A comparison is made between fixed and flexible grids in terms of the spectral bandwidth efficiency. It is concluded that the use of flexible mesh technology is promising when switching to channel speeds above 100 Gbit/s.

Keywords: equalizers, weights, digital signal processing, digital filtering algorithm, Bandwidth, fixed mesh, flexible mesh, number of channels, spectral efficiency, fiber optic transmission system.


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