forward error correction capabilities?

Started by owpex in comp.dsp9 years ago 12 replies

Hello I wanted to know the difference that can exist between(among) a flow of bits that goes out of a decodificador viterbi + Reed solomon and...

Hello I wanted to know the difference that can exist between(among) a flow of bits that goes out of a decodificador viterbi + Reed solomon and the flow of bits originally in a transmission of tdt cofdm That is to say: do I obtain the same result to the exit of the corrector Reed Solomon with a BER before Viterbi of 9-6 that with a BER before Viterbi of 2-2? Said otherwise: Do I obtain...


Order of encoder output in Reed-Solomon encoding

Started by Anonymous in comp.dsp14 years ago 1 reply

Hello: I had a query regarding the encoder transmission format order at the Reed-Solomon encoder output for the commercial standards such...

Hello: I had a query regarding the encoder transmission format order at the Reed-Solomon encoder output for the commercial standards such as European DVB, North American ATSC/ITU-J83 standards etc. For a RS (n,k) code, if the message polynomial is : m(x)=m(0)+m(1)*x+m(2)*x^2+......+m(k-1)*x^(k-1) and the parity polynomial is : c(x)=c(0)+c(1)*x+...........+c(n-k-1)*x^(n-k-1). Is the ree...


Euclidean algorithm used to decode Reed-Solomon codes?

Started by Jaco Versfeld in comp.dsp16 years ago 2 replies

Hi, Two traditional ways to decode Reed-Solomon codes include the Massey-Berlekamp and Euclidean decoding algorithms. Can someone please...

Hi, Two traditional ways to decode Reed-Solomon codes include the Massey-Berlekamp and Euclidean decoding algorithms. Can someone please explain the underlying theory on which the Euclidean algorithm is based, or perhaps give some pointers in literature where it is covered? Does it have anything to do with the Euclidean algorithm used in abstract algebra to compute the GCD? Your ti...


BCH Codes and Reed-Solomon Codes

Started by Randy Yates in comp.dsp15 years ago 15 replies

Does any one know of any research which attempts to analytically determine the the binary codeword subspace (BCH code) of a Reed-Solomon code,...

Does any one know of any research which attempts to analytically determine the the binary codeword subspace (BCH code) of a Reed-Solomon code, that is the binary vector subspace of a subspace of GF(2^m - 1)^n? -- % Randy Yates % "My Shangri-la has gone away, fading like %% Fuquay-Varina, NC % the Beatles on 'Hey Jude'" %%% 919-577-9882 % %%%...


reed solomon decoder Berlekemp massey algorithm

Started by mavricks_009 in comp.dsp14 years ago 1 reply

hey i am implementing reed solomon encoder decoder using verilog. I want to implement a decoder using berlekemp massey algorithm. I am looking for...

hey i am implementing reed solomon encoder decoder using verilog. I want to implement a decoder using berlekemp massey algorithm. I am looking for a hardware of that so that i can write a verilog code. any sort of help is highly appreciated. I am a student.


Regarding Generator Matrices of MDS codes?

Started by Anonymous in comp.dsp13 years ago 2 replies

Hi There, I am a bit confused. If I recall correctly, I have read/learned that any submatrix of a generator matrix is invertible. If one...

Hi There, I am a bit confused. If I recall correctly, I have read/learned that any submatrix of a generator matrix is invertible. If one considers the non-systematic Reed-Solomon code generated by a Vandermonde matrix, this is true. However, if one considers the "Reed-Solomon" code generated by [I | C], where I is a k X k identity matrix, and C is a (k X n-k) Cauchy matrix, not every ...


Reed Solomon error correction question

Started by lindasel in comp.dsp11 years ago 15 replies

I am normally a speech/audio processing engineer, so this is somewhat out of my primary expertise area. I have recently implemented the Reed...

I am normally a speech/audio processing engineer, so this is somewhat out of my primary expertise area. I have recently implemented the Reed Solomon error correction algorithm and have gotten it to work for the following case: the roots of the generator polynomial are in positions 1 through 2t, where t is the number of errors. However, I implemented the case where the roots of the generator poly...


Reed-Solomon error correction capacity

Started by marval in comp.dsp11 years ago 15 replies

Hi: I am a newbie on Reed-Solomon coding, and I was wondering what happens when the received message has more errors than the error...

Hi: I am a newbie on Reed-Solomon coding, and I was wondering what happens when the received message has more errors than the error correcting capacity 2t. I would say that the decoding fails completely, but I am not sure. Could anybody explain this to me?, is there anyway to prevent my decoding from crashing when the received message contains more than 2t errors? Thanks


Reed Solomon Simulation

Started by cpshah99 in comp.dsp11 years ago 14 replies

Hi All I want to simulate Reed Solomon code with code rate 1/2 to compare rate 1/2 convolution code, I know that rate 1/2 RS will perform...

Hi All I want to simulate Reed Solomon code with code rate 1/2 to compare rate 1/2 convolution code, I know that rate 1/2 RS will perform better. So far I was using RS code of polynomial [255 239]; Can anybody please tell me how to simulate rate 1/2 code? Your help will be appreciated. Thanks Chintan


Erasures decoding of Reed Solomon codes

Started by Mike McLernon in comp.dsp3 years ago 10 replies

Hi, I'm building an erasures decoder for Reed Solomon codes, and I'm having trouble when the number of erasures (without errors) exceeds...

Hi, I'm building an erasures decoder for Reed Solomon codes, and I'm having trouble when the number of erasures (without errors) exceeds (n-k)/2, the error-correcting capability of the code. When my code has no errors, and only erasures, I would expect the error locator polynomial to be uniquely 1. When I have up to (n-k)/2 erasures, that's exactly what happens. However, when the nu...


Reed Solomon decoder -help

Started by Zeph80 in comp.dsp12 years ago 3 replies

This is the first time Ive implemented a Reed Solomon decoder, and Im having some strange problems , which I have not been able to debug. Ive...

This is the first time Ive implemented a Reed Solomon decoder, and Im having some strange problems , which I have not been able to debug. Ive implemented a RS(255,191) code. That makes it a lil hard to verify all steps of my C code by calculations on paper. Anyways, Ive tried Euclids and Berlekamp in C, I always get the correct error locations, but my magnitudes are not correct. If my Error l...


Reed-Solomon encoder in Matlab

Started by ramsay in comp.dsp6 years ago 5 replies

Hi, I am trying to use the Reed-Solomon encoder in the Matlab Communications toolbox ( command rsenc). For example if you are trying to a...

Hi, I am trying to use the Reed-Solomon encoder in the Matlab Communications toolbox ( command rsenc). For example if you are trying to a (7,3) R-S encoder. When you use rsenc the inputs and outputs have are alphabets in the respective Galois fields ( GF(8) in this example). Is there a way to convert the input and output formats such that we can input a binary string and get a binary string o...


Reed-Solomon Coding under ITU-J.83 Annex-B

Started by jitu007 in comp.dsp12 years ago

Hiiiii, I am Jitendra,Comm.Engg. making Reed-Solomon Codec using specs of ITU-J.83 Annex-B. Specs are : n=128,k=122, under...

Hiiiii, I am Jitendra,Comm.Engg. making Reed-Solomon Codec using specs of ITU-J.83 Annex-B. Specs are : n=128,k=122, under GF(128), 7-bit symbol, Generator Polynomial : G(x)=(x+alpha^1)(x+alpha^2)(x+alpha^3)(x+alpha^4)(x+alpha^5); As per the standard I come up with a encoder, But I didnt have any reference to verify/check my codeword. In matlab, RS functions are taking n and k ...


Reed solomon Berlekemp massey algorithm

Started by mavricks_009 in comp.dsp13 years ago 1 reply

I am designing a reed solomon decoder encoder in verilog. while designing I was unable to calculate delta using Berlekmp massey algorithm. It...

I am designing a reed solomon decoder encoder in verilog. while designing I was unable to calculate delta using Berlekmp massey algorithm. It will be great help if you can give me some hint. delta(k) = syndrome(k) - sumation( lambda(k-1) * syndrome(k -i) lambda is something like zx^3+ ax2+ bx+1 syndrome is y by solving this suppose we get the delta = k. http://www.ee.ucla.edu/~ma...


Fair comparision: Reed Solomon code and convolutional code

Started by cpshah99 in comp.dsp11 years ago 13 replies

Hello People I want to compare Reed Solomon code [255,239] and rate 1/2 convolution code with constraint length 5, i.e. generator polynomials...

Hello People I want to compare Reed Solomon code [255,239] and rate 1/2 convolution code with constraint length 5, i.e. generator polynomials are [23 35]_8; Now, my channel is frequency selective, doppler effect and noise. Also the way I am scaling the noise is sigma=sqrt(0.5*Eb/(Rc*snr_lin)) where for RS, the Rc=239/255 and for convolution encoder Rc=1/2; Is this fair compari...


Reed Solomon Encoder

Started by florence8106 in comp.dsp13 years ago

Hello I am modelling a magnetic recording channel and implementing the reed solomon encoder and decoder for better error correcting codes. My...

Hello I am modelling a magnetic recording channel and implementing the reed solomon encoder and decoder for better error correcting codes. My system input is the random binary interger. then I AM using RS (256,239), is that any ways that i can input the binary string for RS Encoder and Display in binary after the encoder ? The binary output of the RS encoder is that go to the magnetic recording...


Difficulty with article regarding decoding Reed-Solomon codes

Started by Jaco Versfeld in comp.dsp3 years ago 2 replies

Hi, I am trying to implement the pseudocode given in the article "A new decoding algorithm for correcting both erasures and errors...

Hi, I am trying to implement the pseudocode given in the article "A new decoding algorithm for correcting both erasures and errors of Reed-Solomon codes" (appeared in IEEE Transactions on Communications, vol. 51, no. 3, March 2003). In section IV, the authors present an algorithm, (Algorithm 2), to decode both erasures and errors, using an algorithm based on the Euclidean algorithm toge...


CCSDS Reed-solomon decoding- error evaluation

Started by Raju_srk in comp.dsp9 years ago

Hi, I'm making a CCSDS reed-solomon decoder. I'm using the C code as written by Simon Rockliff (1991) as a starting point. The main feature of...

Hi, I'm making a CCSDS reed-solomon decoder. I'm using the C code as written by Simon Rockliff (1991) as a starting point. The main feature of the CCSDS specification is that it uses alpha^11 as primitive element and generator polynomial roots are : alpha^(128-E) to alpha^(127+E), which makes the problem unusual. In the above C code, by changing the generator polynomial and using the roots of ...


Reed Solomon: time vs. frequency domain algorithms

Started by lindasel in comp.dsp11 years ago 3 replies

These questions refer to a thesis posted on the Internet. Author: Chih-Lung Shih Title: Soft IP Generator of Reed Solomon Codec for...

These questions refer to a thesis posted on the Internet. Author: Chih-Lung Shih Title: Soft IP Generator of Reed Solomon Codec for Communications Systems Location: National Central University, Taiwan In Fig. 1.4 there is a chart which lists some algorithms as frequency domain and others as time domain. Berlekamp-Massey is classofoed as a frequency domain algorithm. The Euclidian algorithm...


Question about Reed-Solomon error control code

Started by Anonymous in comp.dsp14 years ago 2 replies

Hi, I am simulating equalizer with Reed-Solomon channel code a frequency fading channel. The fading channel has a severe spectral null, I...

Hi, I am simulating equalizer with Reed-Solomon channel code a frequency fading channel. The fading channel has a severe spectral null, I use frequecy domain equalization to contre the null. At present I think the equalizer works well. When I add the RS(170,180) (8 bit) channel code for a data frame, I find the BER performance is not improved at all. It is even worse a little bit than that o...