Direct error correction

Direct error correction ( Forward Error Correction, FEC , error-correcting coding) is a coding / decoding technique that allows error correction to be performed using the forward error method. It is used to correct failures and errors during data transmission by transmitting excessive service information, on the basis of which the original contents of the package can be restored. In practice, it is widely used in computer LANs, LANs, and various telecommunication networks. Codes that provide direct error correction require more redundancy in the transmitted data than codes that only detect errors.

In satellite television, when transmitting a digital signal, for example, with FEC 7/8, eight bits of information will be transmitted: 7 bits of useful information and 1 control bit ^[1] .

In practice, only 5 types are used in DVB-S :

• 1/2
• 2/3
• 3/4 (most popular)
• 5/6
• 7/8

All things being equal, it can be argued that the lower the FEC value, the fewer packets are acceptable to lose, and, therefore, the required signal quality is higher.