Reply by owpex September 12, 20102010-09-12
>I have training with matalb and de differences of the result >between a señal with error rate(before viterbi) -6 and a signal >with error rate -3(before viterbi) is cero > >from the view of the instaler is more easy to make a installation >with a ber of -3 than with a ber of -6 > >Could someboby tell me with is the difference between those two >signals from the point of view of the result? > >thank you again and sorry for my english >
up :D
Reply by owpex June 15, 20102010-06-15
I have  training  with matalb  and  de  differences   of  the  result 
between  a  señal with  error  rate(before  viterbi)  -6  and  a signal
with  error  rate  -3(before  viterbi)  is  cero

from the view  of  the instaler is  more  easy to make  a installation  
with a ber  of  -3  than with a ber  of  -6

Could  someboby  tell  me  with is  the difference  between those  two
signals from the  point  of  view  of  the result?

thank you  again and  sorry for  my  english 
Reply by Vladimir Vassilevsky December 27, 20092009-12-27

Steve Pope wrote:

> Vladimir Vassilevsky <nospam@nowhere.com> wrote: > > >>Translate the question through Babelfish twice: in forward and in >>backward direction. > > > That's the BCJR algorithm isn't it?
It's more like TURBO decoding iteration. VLV
Reply by Steve Pope December 27, 20092009-12-27
Vladimir Vassilevsky  <nospam@nowhere.com> wrote:

>Translate the question through Babelfish twice: in forward and in >backward direction.
That's the BCJR algorithm isn't it? Steve
Reply by Vladimir Vassilevsky December 27, 20092009-12-27

Rune Allnor wrote:

> On 27 Des, 03:23, robert bristow-johnson <r...@audioimagination.com> > wrote: >>On Dec 26, 7:59 pm, "owpex" <chipko...@hotmail.com> wrote: >> >>>Thank you very much and sorry for my translator-english >> >>i ain't never even heard of no "decodificador" beferr. > > > Give the guy a break. > > Given his two posts, it seems he is for real and actually > have used some translator-bot to translate the message from > whatever his native language is. I can hardly imagine the > reverses situation where I were forced to formulate a question > in, say, Japanese to get help.
Translate the question through Babelfish twice: in forward and in backward direction. Modify the original text until the output will be more or less sensible; hopefully it will be reasonable in Japanese as well. Perhaps, such procedure of optimization could be automated. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
Reply by Rune Allnor December 27, 20092009-12-27
On 27 Des, 03:23, robert bristow-johnson <r...@audioimagination.com>
wrote:
> On Dec 26, 7:59&#2013266080;pm, "owpex" <chipko...@hotmail.com> wrote: > ... > > > > > Thank you &#2013266080;very much and sorry &#2013266080;for my translator-english > > i ain't never even heard of no "decodificador" beferr. &#2013266080;
Give the guy a break. Given his two posts, it seems he is for real and actually have used some translator-bot to translate the message from whatever his native language is. I can hardly imagine the reverses situation where I were forced to formulate a question in, say, Japanese to get help. Rune
Reply by robert bristow-johnson December 26, 20092009-12-26
On Dec 26, 7:59&#2013266080;pm, "owpex" <chipko...@hotmail.com> wrote:
...
> > Thank you &#2013266080;very much and sorry &#2013266080;for my translator-english
i ain't never even heard of no "decodificador" beferr. i wonders what them things is. where can i pick me up one of them decodificadors? maybe at the same place where i get my Kalman filters, are they expensive? ;-) r b-j
Reply by owpex December 26, 20092009-12-26
My interest takes root in knowing the qualit diferencia of image
between(among) a sign, for example, with BER before Viterbi of 1e-6 and
other one with BER of 1e-2 
From the point of view of the technician installer is interesting to be
able to offer to a client the major quality of possible image, but visually
it is very difficult to know the quality of a digital image 
If an image with BER before Viterbi of 1e-6 has almost the same quality
that one of BER before Viterbi of 1e-2 probably does not deserve to the
pena to invest(invert) in improving the quality of receipt looking for
better emplacements for to the antena since this work podrian it being done
by the correctors Viterbi and Reed Solomon 

Thank you  very much and sorry  for my translator-english
Reply by Vladimir Vassilevsky December 21, 20092009-12-21

Eric Jacobsen wrote:
> On 12/21/2009 10:17 AM, Vladimir Vassilevsky wrote: >> Eric Jacobsen wrote: >> >>> The slope gets difficult to measure below error rates of 10e-9 or >>> 10e-10 or so just because the tests take so long to run, and at some >>> point in a practical system the limits of the dynamic range and noise >>> floor will be reached. >> >> >> Brute force simulation isn't practical for low BERs, however it is >> simple enough to derive the estimates in that case. >> > Even with real equipment running real-time it's hard to measure 10e-9 or > below with most system.
For real or simulated system, the case of marginally low BER is tractable. So the expected BER can be estimated from noise floor and code performance. There is no need to make long runs unless the goal is verification of the decoder operation. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
Reply by Eric Jacobsen December 21, 20092009-12-21
On 12/21/2009 10:17 AM, Vladimir Vassilevsky wrote:
> > > Eric Jacobsen wrote: > > >> The slope gets difficult to measure below error rates of 10e-9 or >> 10e-10 or so just because the tests take so long to run, and at some >> point in a practical system the limits of the dynamic range and noise >> floor will be reached. > > Brute force simulation isn't practical for low BERs, however it is > simple enough to derive the estimates in that case. > > Vladimir Vassilevsky > DSP and Mixed Signal Design Consultant > http://www.abvolt.com
Even with real equipment running real-time it's hard to measure 10e-9 or below with most system. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com