Forward Error Correction (FEC) - A technique used with noisy or unreliable data streams such as spread spectrum RF transmission. FEC adds error correcting codes to a data stream at a low level. These codes -- typically Reed-Solomon codes -- are used for both error detection and correction. Because FEC is usually used with media where noise or crosstalk are problems, error bursts are likely. An error code with reasonable burst error detection capability is required. FEC can be, and often is, implemented transparently at a low level in a link that includes higher level error detection and handling as well.
The use of FEC can raise the reliability of an unreliable data channel and/or increase the throughput of a data channel that uses retransmission to achieve reliability. It is sometimes used to allow lower power to be used in RF links by correcting the errors introduced from fading of, or interference to, a low power signal.
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Copyright 1994-2002 by Donald Kenney.