BER performance of Viterbi decoder

>
>lanbaba wrote:
>> > From fig.29 it is clear that the 7/8 code actually results in the
loss
>> >in BER at the channel BER = 7e-3, and this is what is anticipated.
>> >
>> >VLV
>> >
>>
>> Sorry, but why that? In Fig. 29 of the Xilinx data sheet, the coded BER
is
>> about 0.0008 with code rate 7/8 for uncoded BER = 0.007, 10 times
lower, or
>> do I see something fundamentally wrong?
>>
>> LBB
>
>Thats what I see also....
>
>I see approx 2dB gain?????
>
>please explain....
>
>Mark
>


I could not verify Xilinx data with Matlab's vitdec.m nor with own Viterbi
decoder. Would really want to know how to interpret that curves in Xilinx
data sheet. Hopefully they are not fakes.

LBB