Re: [Discuss-gnuradio] A problem of the turbo channel coding!

[Brian Padalino]

On Fri, Sep 12, 2008 at 8:37 AM, Shucai Xiao <address@hidden> wrote:
> Hi, all
>
>
>
>          Currently, I am trying to establish a data transmission system
> using the Viterbi coding method as the channel coding.
>
>          I found a problem that the output of the coding module is short
> type,
>
>          Enc = trellis.encoder_ss(f, 0)
>
>
>
>          While the decode module needs a float type
>
>          Va = trellis.viterbi_s(f, K, 0, -1)
>
>
>
>          Can some one tell me how to make them compatible?

The encoder works on hard data bits that you want to transmit over the air.

The decoder works on soft decision bits that you have received.

Scale your encoder bits to be within the soft decision range.

Brian