CPC H04B 10/6164 (2013.01) [H04B 10/07951 (2013.01); H04B 10/25759 (2013.01); H04B 10/516 (2013.01); H04B 10/616 (2013.01); H04L 1/1657 (2013.01); H04L 7/0075 (2013.01); H04L 25/03305 (2013.01); H04L 25/03331 (2013.01); H04L 27/0014 (2013.01); H04L 27/2662 (2013.01); H04L 69/22 (2013.01); H04B 10/6161 (2013.01); H04L 2027/0026 (2013.01)] | 23 Claims |
1. An apparatus comprising:
a receiver circuit operable to receive a modulated optical signal and provide digital samples based on the modulated optical signal; and
processor circuitry operable to:
receive the digital samples indicative of data frames from the receiver circuit;
determine estimated positions of framer indices in the data frames, the data frames including framer symbols indicative of positions of frame headers in the data frames;
identify, using a non-linear filter, a subset of estimated positions of the determined estimated positions of the framer indices that are greater than a threshold distance away from a median index position of the determined estimated positions of the framer indices;
generate a second subset of estimated positions by removing the subset of estimated positions from the determined estimated positions across the data frames; and
determine an estimated framer index position of the data frames by determining an average position of the second subset of estimated positions.
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