Joint Polarization Dependent Loss and Polarization Mode Dispersion Tolerance for Single-Carrier Coherent System Using Block Reversal Alamouti Coding

The Alamouti space-time block code (STBC) has been shown to efficiently tolerate polarization dependent loss (PDL) due to its time slot orthogonality. However, if there is large polarization mode dispersion (PMD) in the transmission link, the ability of Alamouti STBC to tolerate PDL will be greatly compromised. In this paper, we demonstrate the block reversal Alamouti (BR-Alamouti) coding scheme that can jointly tolerate large PDL and PMD in the single-carrier coherent system. This coding scheme can achieve orthogonality in the frequency domain by time-reversing partial Alamouti-coded data blocks in the time domain. The performance of the BR-Alamouti is verified in the 20-GBaud QPSK coherent system based on both simulation and experiment platforms. The simulation and experiment results confirm that the BR-Alamouti provides excellent performance and stability to jointly deal with random polarization rotation and a large range of differential group delay (DGD) up to 100 ps and PDL up to 8 dB compared to the traditional Alamouti coding.