Error detection and correction
Noise or error is the main problem in the signal,
Which disturbs the reliability of the communication system as error control coding is a coding procedure that is implemented to control the occurrence of errors,
There are many different error-correcting codes depending on the mathematical principles applied to them, but these codes are categorized into linear block codes and convolution codes.
What is error control coding?
Error control coding: It is a coding procedure that is implemented to control the occurrence of errors, which helps these techniques to detect and correct errors,
It is a method of providing reliable transmission and storage of digital data when the communication medium used has an unacceptable bit error rate (BER) and a low signal-to-noise ratio (SNR).
Error coding is used in many digital applications such as computer memory, magnetic and optical data storage media, satellite communications, deep space, network communications, and cellular phone networks.
Instead of transmitting numerical data in raw bits to bits, the data is encoded in additional bits at the source, and then the longer code word is sent.
The receiver can decrypt it to retrieve the requested information,
The extra bits also convert the data into a valid code word in the cipher, since the area of valid code words is smaller than the area of possible bit strings of this length.
Thus, the destination can identify invalid code words.
In computing, telecommunications, information theory, and cryptographic theory, error correction code and sometimes error correction code (ECC) are used to control errors in data over unreliable or troublesome communication channels.
In every communication system, an error occurs in the data
Therefore, we do something called correction and error detection It means Error detection and correction
This is done by having a Chip inside the transmitter called an encoder that adds some bytes with the data before sending and after receiving the data on the other side, using these bytes for error detection and correction
This technology is called FEC so that when you see the word FEC on Telecom, you know what it means Forward error correction
Error Correction Mode:
The FEC-based system uses redundant coding to correct possible error bits to ensure bit error-free transmission.
Practical example:
If you follow a video signal for every 188 bytes of data, you will add 16 bytes to the FEC
The advantages of this technology are error correction and increased system reliability.
But it also has drawbacks, which are Consume bandwidth increase latency, which means that it consumes part of the data transfer speed and also increases the delay in data arrival.
key Indicator: NCG
When FEC is not used, the system bit error rate (BER) on the 1e-15 level requires a 22 dB OSNR.
When FEC is used, the system BER on the 1e-15 level requires only an 11 dB OSNR.
Using FEC, an 11 dB OSNR can be reduced.
The decrease in the required OSNR is NCG of the FEC.
NCG is an important indicator to measure the FEC performance of each vendor.
Thank You.
