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 reed-solomon encoder format output by these standards given as: r=[m(0) m(1) .....m(k-1) c(0) c(1) .....c(n-k-1)] or r=[m(k-1) m(k-2) ......m(0) c(n-k-1) ....c(1) c(0)] ???? This is very important since the decoder needs to be aware of the format of the transmission at the encoder side.. Any help would be greatly appreciated. Vikram

# Order of encoder output in Reed-Solomon encoding

Started by ●March 8, 2005

Reply by ●October 3, 20052005-10-03

>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 reed-solomon encoder format output by these standards given as: > >r=[m(0) m(1) .....m(k-1) c(0) c(1) .....c(n-k-1)] > >or > >r=[m(k-1) m(k-2) ......m(0) c(n-k-1) ....c(1) c(0)] ???? > >This is very important since the decoder needs to be aware of the >format of the transmission at the encoder side.. > >Any help would be greatly appreciated. > >Vikram > >Hi Vikram, Co-efficient of highest order X is the first to ENTER the encoder, first to LEAVE the encoder. It is also the FIRST to enter the decoder and exit the decoder... ! Rider This message was sent using the Comp.DSP web interface on www.DSPRelated.com