Forward error correction in optical core and optical access networks

Abstract

Forward error correction (FEC) techniques are essential for optical core and optical access networks. In optical core networks, the emphasis is on high coding gains and extremely low output bit error rates, while allowing decoder realizations to operate at a throughput of 100 Gb/s and above. Optical access networks operate at 10 Gb/s or above and require low‐complexity FEC codes with low power consumption. Coherent optical transmission with higher order modulation formats will become mandatory to achieve the high spectral efficiencies required in next‐generation core networks. In this paper, we provide an overview of these requirements and techniques, and highlight how coding and modulation can be best combined in optical core networks. We also present guidelines for modulation and low‐complexity FEC system design for optical access networks. © 2013 Alcatel‐Lucent.

Transmitters mapping of visible light communication system

“…For the worst case scenario, the TMLCM achieved a 12 dB SNR gain over the TTM when UE2 moved along x=1, and a 7 dB SNR gain along x=2. As shown in the results, the minimum SNR for the TMLCM is about 8.5 dB at location (x=1 and y=3), and for the OOK modulation an SNR of 8.5 dB can provide a 10 used to improve the BER for optical systems operated at a few gigabits [35]. From the results in this section it can be clearly seen that TTM does not support high data rates with an acceptable BER.…”

Adaptive receiver for visible light communication system

“…A low-complexity forward error correction (FEC) technique can be used to improve the BER (to further reduce the BER from 10 -5 to 10 -9 ) for optical systems operated at a few gigabits [21]. From the results obtained in this section it can be clearly seen that TWFR does not support high data rates with an acceptable BER.…”

DSP Enabled Optical Detection Techniques for PON

“…This means that we can tolerate an effective net SNR, considering the extra bandwidth required for the coding overhead, that is 4 times lower than without coding. This Reed-Solomon code is the first that found widespread use in fiberoptic communication systems and optical access systems [43].…”