>Hi,
>If I have a 16-QAM demodulator I know I can use the I and Q values to
>access a lookup table and output soft codes for a Viterbi uisng LLR
>
>What do I do if I'm using 16-PAM? If my information is right its just
>amplitude modulation. So out of the demodulator I will get 1 of 16
values.
>How do I then create the soft codes indicating how strong, or weak the
'1's
>and '0's are?
>
>Thanks
>Mike
>
>This message was sent using the Comp.DSP web interface on
>www.DSPRelated.com
>
It's identical to calculating the LLR in 256-QAM. But here you only need
to calculate 4 soft bits in either I- or Q-branch, and not all 8 bits.
LBB
Reply by m2francis●September 9, 20052005-09-09
Hi,
If I have a 16-QAM demodulator I know I can use the I and Q values to
access a lookup table and output soft codes for a Viterbi uisng LLR
What do I do if I'm using 16-PAM? If my information is right its just
amplitude modulation. So out of the demodulator I will get 1 of 16 values.
How do I then create the soft codes indicating how strong, or weak the '1's
and '0's are?
Thanks
Mike
This message was sent using the Comp.DSP web interface on
www.DSPRelated.com