Adaptive Chromatic Dispersion Compensation for Coherent Communication Systems Using Delay-Tap Sampling Technique

Anatomy of a Digital Coherent Receiver

“…Diverse variants of this procedure, each using a different metric, have been shown so far. A criterion derived from constant modulus algorithm (CMA) is used in [10], [11], delay-tap sampling estimator [12], [13], autocorrelation of signal power waveform [14], [15], clock tone search [16]- [18], Gardner time error detector variance [19]. Recently, another technique has been demonstrated, where the sweep over CD values is performed automatically when applying FFT on the autocorrelation of discrete spectrum [20].…”

Chromatic dispersion and nonlinear phase noise compensation based on KLMS method

“…CD compensation is also performed in time domain using tap delay sampling [7,8] and maximum likelihood sequence estimation (MLSE) [9] based on the gradient decent algorithm which can be implemented by decision feedback equalizer (DFE) with less computational complexity in comparison with frequency domain methods. A fractionally spaced equalizer (FSE) in the time domain can compensate sampling time errors [10], by using an oversampling rate of two for CD compensation [5,8,11]. Linear mean square (LMS) algorithm which allows the recovery of signal in blind mode, works in the time domain [10].…”

Experimental demonstration of adaptive digital monitoring and compensation of chromatic dispersion for coherent DP-QPSK receiver

“…In literature different approaches to CD monitoring directly from the received data (blind monitoring) have been presented, such as: parameter extraction from FIR filter coefficients [2], time- [3] or frequency-domain [4] monitors placed before timing recovery stage and delay-tap sampling technique [5].…”