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The essence of Reed-Solomon coding

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Re: The essence of Reed-Solomon coding

#41

Post by vmilner »

aortega wrote: post #26

There are many types of Reed-Solomon codes, each with different amount of redundancy, they are a special case of BCH codes, a kind of code that approach the Shannon limit (the maximum rate of error-free data that can be transferred over a noisy channel). The bandwidth of a channel (like radio, or optical fiber) is not really limited by the media, but only by the noise it has. Optical fiber have almost zero noise, tha…

LDPC coding (combined with BCH coding) is now used for most Western Europe digital and satellite TV in the DVB-T2 and DVB-S2 standards.

Re: The essence of Reed-Solomon coding

#42

Post by aortega »

nayuki wrote: post #40
aortega wrote: post #33

Earlier quoted context omitted.

One important stage of error correction is spreading, that use a pseudo-random function to 'spread' the damaged data over several blocks that can be then completely recovered, instead of concentrating the damage in a single block (like often happen in erasures) that cannot be recovered.

By spreading, I think you're referring to interleaving https://en.wikipedia.org/wiki/Burst_error-correcting_code#In... , which doesn't need randomness. Pseudo-random scrambling is used in places like https://en.wikipedia.org/wiki/64b/66b_encoding to reduce the chances of many consecutive 0s or 1s which could cause clock desynchronization between the sender and receiver.

>By spreading, I think you're referring to interleaving https://en.wikipedia.org/wiki/Burst_error-correcting_code#In... , which doesn't need randomness.

I stand corrected!

Re: The essence of Reed-Solomon coding

#43

Post by [deleted] »

vmilner wrote: post #41
aortega wrote: post #26

There are many types of Reed-Solomon codes, each with different amount of redundancy, they are a special case of BCH codes, a kind of code that approach the Shannon limit (the maximum rate of error-free data that can be transferred over a noisy channel). The bandwidth of a channel (like radio, or optical fiber) is not really limited by the media, but only by the noise it has. Optical fiber have almost zero noise, tha…

LDPC coding (combined with BCH coding) is now used for most Western Europe digital and satellite TV in the DVB-T2 and DVB-S2 standards.

[deleted]

Re: The essence of Reed-Solomon coding

#44

Post by joshspankit »

aortega wrote: post #42
nayuki wrote: post #40

Earlier quoted context omitted.

By spreading, I think you're referring to interleaving https://en.wikipedia.org/wiki/Burst_error-correcting_code#In... , which doesn't need randomness. Pseudo-random scrambling is used in places like https://en.wikipedia.org/wiki/64b/66b_encoding to reduce the chances of many consecutive 0s or 1s which could cause clock desynchronization between the sender and receiver.

>By spreading, I think you're referring to interleaving https://en.wikipedia.org/wiki/Burst_error-correcting_code#In ... , which doesn't need randomness. I stand corrected!

> I stand corrected!

Heh

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