Statistical measurements of BER fluctuations due to PMD in 10-Gb/s optical transmissions

Polarization-mode dispersion induces signal fading and fluctuating power penalties in optical systems. The intrinsic uncertainty of the bit error rate (BER) measurements combined to the time needed to perform power adjustments for a power penalty measurement can completely distort the statistics of the as-measured power penalties. We show that measuring the BER statistics and using the receiver sensitivity power dependence gives a better measurement of the power penalty statistics. The influence of the statistics of error detection in the measurements must be considered in order to define the correct measuring time for each situation.