Abstract: The disclosed systems and methods for frequency domain (FD) local oscillator frequency offset (LOFO) compensation. The method comprising: i) compensating, by an integer Fast Fourier Transform (FFT) bins-based oscillator, LOFO in a received signal by an integer number of FFT bins; and ii) compensating, by a fractional FFT bins-based oscillator, LOFO in the compensated signal by the integer FFT bins-based oscillator with a fine compensation resolution of a fractional number of FFT bins.

Abstract: The disclosed systems and methods for compensating the polarization dependent loss (PDL) in communication networks comprising: i) filtering, by a first feed-forward filter, a current set of symbols in an equalized X-Pol signal; ii) filtering, by a second feed-forward filter, a current set of symbols in an equalized Y-Pol signal; iii) filtering, by a first feed-backward filter, a previously decided set of symbols associated with the equalized X-Pol signal; iv) filtering, by a second feed-backward filter a previously decided set of symbols associated with the equalized Y-Pol signal; v) adding, by a first adder, the outputs from the first feed-forward filter and the second feed-forward filter; and vi) subtracting, by the first adder, the outputs from the first feed-backward filter and the second feed-backward filter from the addition of outputs from the first feed-forward filter and the second feed-forward filter to determine the symbols in the equalized X-Pol signal.