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From: VB VB on 5 Jun 2010 04:50
Hi everyone!
Some question to all.
I simulate DVB-T system with concatenated coding. In this system the convolution coding as a inner code and RS code as a outher are used. DVB-T system must operate in QEF mode then BER after Viterbi decoding is equal 10^-4 and BER after RS decoder is equal 10^-11. But then i try to measure the BER with standard Simulink BER block i fix on display block after Viterbi that BER is equal approx. 10^-4 (this is correct), but after RS decoding BER is equal to zero (this is dont correspond to true). Then BER after Viterbi is equal for example 10^-3, then BER after RS is indicated again zero. But this can't be. BER block after RS begin to indicate value > 0, then BER is equal approx. 0.1. Then i try to encourage this by stating Display properties to long format, then long e format, and so on. But this don't fix the problem.

The question is following - how to indicate on display block+BER block the BER for example 10^-11 or 10^-9?
From: sscnekro on 5 Jun 2010 05:27
> The question is following - how to indicate on display block+BER block the BER for example 10^-11 or 10^-9?

Is your problem just with displaying numbers in a certain format, or first of all, a fix in your computation?
From: Andreas Lobinger on 5 Jun 2010 05:57
Aloha,

On Sat, 05 Jun 2010 08:50:08 +0000, VB VB wrote:

> equal 10^-4 and BER after RS decoder is equal 10^-11. But then i try to
> measure the BER with standard Simulink BER block i fix on display block
> after Viterbi that BER is equal approx. 10^-4 (this is correct), but
> after RS decoding BER is equal to zero

> The question is following - how to indicate on display block+BER block
> the BER for example 10^-11 or 10^-9?

You are aware, that you need to transmit 10^11 bits first, to capture that
1 bit wrong to show BER = 10^-11?
From: VB VB on 5 Jun 2010 07:35
You mean, that i must wait of time to the moment, then number of transmitted bits is being equal to 10^11? I of cause trying to wait, but for example for Viterbi decoding BER is unequal to zero even on start of simulation (for high values of AWGN). This caused by the fact, as i understand, that BER is computed as (number of errors)/(number of transmitted bits) and he gives instanteneous value of BER in every moment of simulation time. I am right?
Considering above BER after RS must generate BER value rigth after computation delay or receive time is over?
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