forward error control

Forward error control (FEC) is a method used in communications to protect transmitted information from errors caused by noise. It works by adding redundant bits to the original data. These extra bits allow the receiver to detect and correct errors that may occur during transmission.12

Unlike automatic repeat request (ARQ) systems, which only detect errors and request retransmission, FEC aims to correct errors directly. This is particularly useful in situations where retransmission is difficult, such as in deep-space communication.13

Simple examples of FEC include repetition codes, where data bits are sent multiple times, and the Hamming code, which adds parity bits to detect and correct single-bit errors. While FEC requires more redundant bits than error-detecting codes, it offers the advantage of automatic correction.123