## Forums Search for: Reed Solomon

## How to understand the syndrome of Reed Solomon code

Hi, In the following description of RS code, Syndrome S first said the remaider of R mod G. Then, it is said C is multiple of G. I feel...

Hi, In the following description of RS code, Syndrome S first said the remaider of R mod G. Then, it is said C is multiple of G. I feel that it is controversy here. C mod G has 0 remainder? Could you explain it to me? thanks a lot .................... Let C be the code word without any errors, R be the received code word and E be any error that the channel introduces. The...

## Request for the C Code for Erasure Decoding

inHell All, Can somebody Please provide me with a reliable source for studding and implementing a Reed Solomon Decoder capable of correcting...

Hell All, Can somebody Please provide me with a reliable source for studding and implementing a Reed Solomon Decoder capable of correcting Erasures? I have already implemented the syndrome detector, the Erasure Polynomial, Berlekamp ? Massey Algorithm and the program (written in C using VC++) is capable of finding the correct error / erasure locator polynomial but for some reason the (

## Question on Dual-Line RS decoder

inHello, I have been reading the excellent paper titled "A HIGH-SPEED AND LOW-LATENCY REED-SOLOMON DECODER BASED ON A DUAL-LINE STRUCTURE" by...

Hello, I have been reading the excellent paper titled "A HIGH-SPEED AND LOW-LATENCY REED-SOLOMON DECODER BASED ON A DUAL-LINE STRUCTURE" by Hyeong-Ju Kang and In-Cheol Park. I have been able to understand the algorithm as it is described, and have also been able to reproduce it successfully in software in order to calculate the Error Locator Polynomial. However I have been stru

## Complexity of reed-solomon (n, k) over m-bit symbol field

inI am trying to learn RS deeper. For the most conventional RS(n,k) defined for a m-bit symbol field , we let n=2^m to maximize the codeword...

I am trying to learn RS deeper. For the most conventional RS(n,k) defined for a m-bit symbol field , we let n=2^m to maximize the codeword block size. Its decoding complexity is known to be O(n log^2 n). But if we let n to be independent of m, then what will be the decoding complexity?

## Why there is an extra error when I try to correct more than the capacity?

inHi I am Krishna Chaitanya. I am trying to implement reed-solomon codes and check what is the performance of the coding scheme. I am using n=31...

Hi I am Krishna Chaitanya. I am trying to implement reed-solomon codes and check what is the performance of the coding scheme. I am using n=31 and k=29. This means that it has to correct 2 symbols(5 bits each). I would like to know few things about the error correction codes. When ever I induce more than 1 symbol error, that is lets say I introduce and error of 7 bits, now the error correc...

## Proving that the codebook of an (n,k) RS code is an ideal?

inHi, How can I prove that the (n,k) RS code book, i.e. all the valid code words of the specific (n,k) Reed-Solomon code, is an ideal? The...

Hi, How can I prove that the (n,k) RS code book, i.e. all the valid code words of the specific (n,k) Reed-Solomon code, is an ideal? The (n,k) RS code has a generator g(x), consisting of n-k consecutive roots in GF(2^m). (I.e. a valid RS codeword is divisible by g(x)) Also, g(x), the generator polynomial has order n, i.e. g(x) divides x^n-1. For an ideal, the following must hold: A...

## Why use BCH but not RS as out-code in DVB-S2?

inHello all, I am simulating the ECC code in DVB-S2. I found the error after LDPC decoding is mostly burst errors. And papers said when handling...

Hello all, I am simulating the ECC code in DVB-S2. I found the error after LDPC decoding is mostly burst errors. And papers said when handling burst errors, Reed-solomon is better than BCH. But why use BCH? Is BCH's decoder simpler than RS? Any ideas will be appreciated. Best Regards, Davy

## DVB-H FEC decoder question ...

inHello, I was looking at the DVB-H standard which has a serially concatenated encoding with Reed Solomon code (RS(204,188, t=8) from...

Hello, I was looking at the DVB-H standard which has a serially concatenated encoding with Reed Solomon code (RS(204,188, t=8) from RS(255,239, t=8) ) as the outer code and Convolution code (K=7) as the inner code. At the receiver, I can think of at least four decoding options, 1. Viterbi followed by RS decoder. 2. MAP (BCJR) followed by RS decoder. 3. MAP followed by soft input RS decode...

## Reed-Solomon syndrome equation solution question

inGood afternoon: I have implemented an RS encoder and decoder in GF16 and GF256. It works for the case when the first root of the generator...

Good afternoon: I have implemented an RS encoder and decoder in GF16 and GF256. It works for the case when the first root of the generator polynomial is alpha^1, the usual case shown in textbooks. I have been able to reproduce the textbook examples and it worked for a test of 10,000 random messages with random error locations and error values (t=3). However, when I try to use alpha^2 as...

## Reed Muller Code

I am looking for Reed Muller Encoder,Decoder Implementation in C/C++....Additional theory links can be helpful as well..Waiting...

I am looking for Reed Muller Encoder,Decoder Implementation in C/C++....Additional theory links can be helpful as well..Waiting for reply.. Cheers

## FIFO sampling in the modulator

I woul'd like to know if someone have information about FIFO in ATSC modulator. This FIFO is located at the Data Randomizer input. The...

I woul'd like to know if someone have information about FIFO in ATSC modulator. This FIFO is located at the Data Randomizer input. The finality of it is generate some null time to be consumed for anothers blocs (Reed Solomon, Trellis, Sync, Field Sync, and pilot). I am looking for information about amount of data in FIFO and clock rate. Thanks

## Regarding the working of Cyclic Codes

Hello all, I also tried to implement a cyclic code with very high values of (n,k)=(117,102). When I tried that and check if the code is able...

Hello all, I also tried to implement a cyclic code with very high values of (n,k)=(117,102). When I tried that and check if the code is able to correct all the 2 bit errors, it was not able to do that. The minimum distance for the code is 6 but it was not able to correct all the 2 bit errors. Could you let me know why this is happening. I have one more question about the REED SOLOMON CODES....

## Puncturing BCH codes

inHi, Does anyone have any references on puncturing BCH codes? Is there a closed form solution for the effect puncturing has on a the...

Hi, Does anyone have any references on puncturing BCH codes? Is there a closed form solution for the effect puncturing has on a the codes minimum distance? Is puncturing even done on BCH codes? It seems puncturing a Reed-Solomon code is fairly common, but I am unable to find any mention of punctured BCH codes anywhere. thanks, -Sam

## Negative Input values to RS encoder

inI want to feed negative values to the input of reed solomon encoder?? is this means that i have to use Binary RS encoder ,and if so ,how can...

I want to feed negative values to the input of reed solomon encoder?? is this means that i have to use Binary RS encoder ,and if so ,how can i convert the negative values to a BIT assignment.??

## Massey-Berlekamp vs Euclid's decoding?

inHi, Is there a performance difference between the Massey-Berlekamp decoder and the decoder based on Euclid's algorithm for Reed-Solomon...

Hi, Is there a performance difference between the Massey-Berlekamp decoder and the decoder based on Euclid's algorithm for Reed-Solomon decoding? (decoding failures, speed of execution, etc.) Which one is the most popular in practical systems, and which one is the easiest to implement? (Does anyone have pointers in literature where an Errors-and-Erasures Euclid decoder is discussed, e...

## question on WiMax 802.16 ReedSolomon parity position

inDear all what are the advantage or disadvantage when we prepend or append the Reed Solomon (RS) parity ? notation: systematic RScodec...

Dear all what are the advantage or disadvantage when we prepend or append the Reed Solomon (RS) parity ? notation: systematic RScodec (n,k,t) n is code length k is message length t is correcting ability m = message m(0)...m(k-1) p = parity p(0)...p(2t-1) where 0 is MSB append style [m(0) ...m(k-1) p(0)..p(2t-1)] prepend style [p(0)..p(2t-1) m(0) ...m(k-1) ] case study: WiM...

## question on convolutional interleaver

inI am using convolutional interleaver for DVB-T. DVB-T uses shortened (204, 188) Reed Solomon code. The output is sent to a convolutional...

I am using convolutional interleaver for DVB-T. DVB-T uses shortened (204, 188) Reed Solomon code. The output is sent to a convolutional interleaver with depth 12 and slope 17. I tested it in Matlab and am using the function 'convintrlv'. After the convolutional interleaver, the interleaved symbols contain many zero symbols because of the delay registers. my question is, are we gonna sen...

## Help: need Reed-Solomon C++ code for RS(4, 2) and RS(24, 20) on 6 bit symbols

inYou may guess i'm trying to correct CD subcodes R-W in software. Symbols are 6 bits each. I've seen the code here:...

You may guess i'm trying to correct CD subcodes R-W in software. Symbols are 6 bits each. I've seen the code here: http://www.eccpage.com/rs.c and a lovely explaination here: http://www.4i2i.com/reed_solomon_codes.htm my problem is, with s=6 (mm in the aforementioned code) that means my data n is 63 symbols long. but it's not, it's explicitly 4 symbols long, with 2 parity symbols (t =...

## Reed Solomon Confirmation

Hi, I was wondering if anyone out there has a way of confirming a (6 byte) RS parity with known data. I have written a program that computes...

Hi, I was wondering if anyone out there has a way of confirming a (6 byte) RS parity with known data. I have written a program that computes the (6 byte) RS parity and have confirmed the program works with http://cm.bell-labs.com/who/emina/applets/FFCalc.html but this calculator doesnt include 0x00 in the data field. My data is 0xC0, 0x40, 0xF0 and then 25 of 0x00 so the data field i...

## Reed-Solomon Error Locator Roots

inI've got a RS implementation that's producing correct error values for a (204,188) code with generator g(x) =...

I've got a RS implementation that's producing correct error values for a (204,188) code with generator g(x) = (1-a^0x)(1-ax)...(1-a^(2t-1)x) The thing that has me puzzled is that I'm producing the correct error values, but when I go to look at the roots of the error locator, they don't seem to be correct. Example: I placed errors in samples 0-3 of the received codeword, so I would expect to ...