Channel coding is referred to the processes done in both transmitter and receiver of a digital communications system. The mentioned processes require allocating extra bits, a.k.a. parity bits, and consuming extra bandwidth. Using this amount of communications resources results in more reliable connection between transmitter and its receiver. There are two policies to deal with channel coding:
- forward error correction (FEC)
- automatic repeat-request (ARQ)
FEC tries to discover the errors and correct them if it can. However, ARQ just discovers the error and sends a resend request to the transmitter.
