Reed solomon simulation in awgn environment...

[stiltz]

Hi,
I am trying to simulate reed solomon codes on awgn channel . I can not understand how I should add the noise in my encoded signal because the signal is in GF(2 ^m) and if I limit the noise in the corresponding field then it will change the variance of the noise. Can any one guide me ???
Best Regards..

 

[mar_deepmode]

Hi,
I am trying to simulate reed solomon codes on awgn channel . I can not understand how I should add the noise in my encoded signal because the signal is in GF(2 ^m) and if I limit the noise in the corresponding field then it will change the variance of the noise. Can any one guide me ???
Best Regards..

Hello!
Can't you use Simulink from MatLab program to simulate RS on AWGN channel?
If you use it, with a few blocks and you won't have GF problem there.
I think you just have to do GF conversion in MatLab code...

Cheers,
mar_deepmode

 

[stiltz]

Thanx . Actually I am simulating the system in C not in matlab .

 

[bulx]

In a real system you will have to modulate the GF symbols before you send them. You could just send them serially ie; bit by bit (say 0 -> -1 and 1 -> 1). you can add required noise, and do a hard decision at reciever (positive is 1, negative is zero), recode, find BER ...

Also you could map your m bits of a GF element into a 2^m QAM constellation, and send one of the 2^m symbols. then above mentioned process can be done.
-b

 

[stiltz]

what does recode mean ?????????

 

[mar_deepmode]

what does recode mean ?????????

Code it again? :idea:

 

[stiltz]

Do you mean that at sending end first I should encode the data then before transmitting convert it to bits then add the noise and at receiver end received bits should be recoded again and then I should run the decoding algorithms ????????
Will it work ??? I mean to say is it a valid pragmatic approach ????

 

[bulx]

it was typo, i meant "decode", not recode..and for the rest of it: it is just a parallel to serial at Tx and serial to parallel in Rx. perfect symbol synch and knowledge of begining of codeword is assumed.

hope it is clear now
-b

 

[mar_deepmode]

it was typo, i meant "decode", not recode..and for the rest of it: it is just a parallel to serial at Tx and serial to parallel in Rx. perfect symbol synch and knowledge of begining of codeword is assumed.

hope it is clear now
-b

lol
Indeed letters "r" and "d" are close to each other in the keyboard!!