Demonstration of Fibre Impairment Compensation Using Split-Step Infinite-Impulse-Response Filtering Method

In recent years, coherent detection with subsequent Digital Signal Processing (DSP) has emerged as the most promising technique for long-haul optical data transmission. DSP alleviates the requirement for optical phase locking of the Local Oscillator (LO). Moreover, various fibre propagation impairments may be digitally compensated, relieving the need for complex and expensive optical solutions. With coherent detection high spectral efficiency may be achieved, e.g. using Orthogonal Wavelength-Division Multiplexing (OWDM), where channel spacing is equal to the symbol rate. A major difficulty in achieving high spectral efficiency is the combined effect of fibre nonlinearity and dispersion.