What Is FEC forward error correction?
Forward error correction (FEC) is a digital signal processing technique used to enhance data reliability. It does this by introducing redundant data, called error correcting code, prior to data transmission or storage. FEC provides the receiver with the ability to correct errors without a reverse channel to request the re-transmission of data. As we know, sometimes optical signals could deteriorate due to some factors during transmission, which may lead to misjudgment at the receiver end, possibly mistaking “1” signal for “0” signal, or “0” signal for a “1” signal. If the number of errors in transmission is within the correction capacity (discontinuous errors), the channel decoder will locate and correct the false “0” or “1” to improve the quality of the signal.
Why need forward error correction (FEC) ?
As bandwidth demands increase and the tolerance for errors and latency decreases, designers of data communication systems have been looking for new ways to expand available bandwidth and improve the quality of transmission.
So FEC help to solve this problem, a technique has been used for years to enable efficient, high-quality data communication over noisy channels.
The development of Forward Error Correction in optical communications can be divided into three generations.
The first generation FEC represents the first to be successfully used in submarine systems and terrestrial systems. As WDM systems matured, a stronger second generation FEC was installed in commercial systems. The advent of third-generation FEC opened up new vistas for the next generation of optical communication systems.
