DAB : encore et toujours aucune avancée?

matthieu 73 <b0664924973@hotmail.com> wrote in
news:4294ff82$0$303$7a628cd7@news.club-internet.fr:

Je croyais que les limitations actuelles, au niveau des encodeurs, ne
permettaient pas encore d'utiliser le part 10 (H.264) pour ce type
d'usage...

il y a des passerelles logiciel sat vers ip avec transcodage MPEG4.

OK. Quels sont les débits par programme ? Cela fonctionne-t-il depuis
longtemps ?

Il y a eu un essais de réception TNT mais c'est pas concluant pour le
moment. Il y a des soupçons que la couverture de roissy par les
émetteurs de tnt n'est pas suffisante pour une réception correcte.

Là, par contre, j'en doute fort. La tour Eiffel est en LOS depuis Roissy et
la PAR DVB-T est de 23 kW omni. Sannois et Chennevières ne rayonnement
quasiment pas dans cette direction (et de toute façon, l'IG a été augmentée
sur le R1, donc plus de problème d'autobrouillage de ce côté.

A mon humble avis, je pense plutôt à des problèmes liés aux multiples
sources de bruits impulsionnels dans la zone de l'aéroport (à ce sujet, Cf.
http://www.ebu.ch/trev_299-fernandez.pdf ).

Il serait intéressant de savoir si le R1 est plus touché que les autres,
étant donné que sur ce multiplex, en IDF, le FEC a été passé de 2/3 à 3/4
de manière à conserver un débit utile suffisant suite à l'augmentation, en
catastrophe, de l'IG du SFN francilien.

Oui le S-DMB est payant à ce que j'en sais.

En effet. J'ignore, cependant, si les services S-DMB ont déjà commencé,
Nicolas nous en dira certainement plus à ce sujet.

Question connexe : est ce vrai que T-DMB et DMB-T ne désignent pas la
même chose (le premier pour la norme coréenne et le deuxième pour la
chine)?

C'est ce que j'ai lu également, mais je n'ai pas de précisions quant aux
différences concrètes existant entre les deux normes.


--
A+,

Olivier

Olivier Boudot wrote:

<snip>

Yesterday, you said that I lacked experience on the ground, and
criticised me for not listening to people whom you presumably consider
understand this subject better than myself.

Also yesterday, you claimed that DVB-H required 30 dB higher transmitter
powers than DMB. I have accounted for 10 dB out of the 30 dB, but this
10 dB higher transmitter power allows DVB-H to carry 7 times the
capacity that DMB can carry.

Question: where is the remaining 20 dB out of the 30 dB that you claim?

You claim that you understand the subject better than myself. You think
I should listen to people like you because you work in the industry. I
am all ears, Olivier. Where is the remaining 20 dB?

30 dB is a factor of 1000!!! So far, I have accounted for 10 dB, which
is a factor of 10. And 20 dB is a factor of 100. Olivier, at the moment,
you are incorrect by a factor of 100.

I am going nowhere until you either:

1. account for the missing 20 dB that you claim DVB-H requires, or
2. admit that you made a *massive* mistake yesterday.


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

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http://www.digitalradiotech.co.uk/mp3_players_large_capacity.htm

Olivier Boudot wrote:

<snip>

Yesterday, you said that I lacked experience on the ground, and
criticised me for not listening to people whom you presumably consider
understand this subject better than myself.

Also yesterday, you claimed that DVB-H required 30 dB higher transmitter
powers than DMB. I have accounted for 10 dB out of the 30 dB, but this
10 dB higher transmitter power allows DVB-H to carry 7 times the
capacity that DMB can carry.

Question: where is the remaining 20 dB out of the 30 dB that you claim?

You claim that you understand the subject better than myself. You think
I should listen to people like you because you work in the industry. I
am all ears, Olivier. Where is the remaining 20 dB?

30 dB is a factor of 1000!!! So far, I have accounted for 10 dB, which
is a factor of 10. And 20 dB is a factor of 100. Olivier, at the moment,
you are incorrect by a factor of 100.

I am going nowhere until you either:

1. account for the missing 20 dB that you claim DVB-H requires, or
2. admit that you made a *massive* mistake yesterday.


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

Find the cheapest Freeview, DAB & MP3 Player Prices:
http://www.digitalradiotech.co.uk/freeview_receivers.htm
http://www.digitalradiotech.co.uk/dab_digital_radios.htm
http://www.digitalradiotech.co.uk/mp3_players_1GB-5GB.htm
http://www.digitalradiotech.co.uk/mp3_players_large_capacity.htm

DAB sounds worse than FM a écrit :

Olivier Boudot wrote:

<snip>

Yesterday, you said that I lacked experience on the ground, and
criticised me for not listening to people whom you presumably consider
understand this subject better than myself.

Also yesterday, you claimed that DVB-H required 30 dB higher transmitter
powers than DMB. I have accounted for 10 dB out of the 30 dB, but this
10 dB higher transmitter power allows DVB-H to carry 7 times the
capacity that DMB can carry.

Question: where is the remaining 20 dB out of the 30 dB that you claim?

You claim that you understand the subject better than myself. You think
I should listen to people like you because you work in the industry. I
am all ears, Olivier. Where is the remaining 20 dB?

30 dB is a factor of 1000!!! So far, I have accounted for 10 dB, which
is a factor of 10. And 20 dB is a factor of 100. Olivier, at the moment,
you are incorrect by a factor of 100.

I am going nowhere until you either:

1. account for the missing 20 dB that you claim DVB-H requires, or
2. admit that you made a *massive* mistake yesterday.

Il a bientôt fini de nous emmerder dans une langue inconnue en .fr!
Il va se retrouver avec un abuse ce kon

nostradamus wrote:

Il a bientôt fini de nous emmerder dans une langue inconnue en .fr!
Il va se retrouver avec un abuse ce kon

Google's translation tool translates the above to this:

"It soon finished to us emmerder in an unknown language in fr! It will
be found with one deceives this kon"

which doesn't make sense. But assuming that you're criticising me for
writing in English on a French newsgroup, yes, I've already apologised
for this, but I cannot speak French (or any other language), so I can
either not post at all or I have to post in English.

I do not intend to post on here frequently, but I read this thread
yesterday, and both Nicolas Croiset and Olivier Boudet were, in my
opinion, deliberately providing totally false information, so I decided
to correct them.

Personally, I believe that providing correct and truthful information in
a language other than your own takes precedent over people being
provided with incorrect and untruthful information in your own language.

The solution is simple: if they provide correct and truthful
information, I will have no reason to ever post on here again.


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

Find the cheapest Freeview, DAB & MP3 Player Prices:
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http://www.digitalradiotech.co.uk/mp3_players_large_capacity.htm

DAB sounds worse than FM wrote:

Olivier Boudot wrote:

<snip>

Yesterday, you said that I lacked experience on the ground, and
criticised me for not listening to people whom you presumably consider
understand this subject better than myself.

Also yesterday, you claimed that DVB-H required 30 dB higher
transmitter powers than DMB. I have accounted for 10 dB out of the 30
dB, but this 10 dB higher transmitter power allows DVB-H to carry 7
times the capacity that DMB can carry.

Question: where is the remaining 20 dB out of the 30 dB that you
claim?

Additional Information:

Quoting from Wireless Communications, Principles & Practice, by T.S.
Rappaport, sub-section 3.12 Signal Penetration into Buildings, pages
131-132:

"Measurements in Liverpool [Tur 87] showed that penetration loss
decreases with increasing frequency. Specifically, penetration
attenuation values of 16.4 dB, 11.6 dB and 7.6 dB were measured on the
ground floor of a building at frequencies of 441 MHz, 896.5 MHz, and
1400 MHz, respecitvely."

And interpolating these figures to 200 MHz and 500 MHz you would get
penetration losses of:

200 MHz: 18.9 dB
500 MHz: 15.8 dB

In other words, a difference of 3.1 dB

Factors that influence differences in transmitter powers for the same
reception environments (e.g. coverage for indoor reception requires the
highest transmitter powers) are as follows:

* antenna gain
* required C/N
* signal bandwidth
* signal frequency
* building penetration loss


Antenna Gain:

Antenna gain is proportional to the length of the antenna up until the
length equals half a wavelength, i.e. a dipole.

Assuming a mobile phone antenna with a 7 cm long integrated antenna, the
antenna gains are as follows:

At 200 MHz:

antenna gain = 10 log (0.07 / 0.75) = -10.3 dB

At 500 MHz:

antenna gain = 10 log (0.07 / 0.3) = -6.3 dB

Difference = 4 dB higher power required for DMB in Band III

-----------------------------------------------------------------------

Required C/N

DMB using PL3A: 16 dB (quoted from Digital Audio Broadcasting,
Principles & Applications)

DVB-H using 16-QAM, inner code rate of 1/2: 15.1 dB (quoted from DVB-H
Implementation Guidelines, ETSI TR 102 377)

Difference = 0.9 dB higher for DMB

------------------------------------------------------------------------

Signal Bandwidth

The difference is simply:

10 log (DVB-H OFDM bandwidth / DMB OFDM bandwidth)

For an 8 MHz DVB-H channel:

Difference = 10 log (7.64 / 1.536)

Difference = 7.0 dB higher for DVB-H

------------------------------------------------------------------------

Signal Frequency

Quoting the free space loss equation:

Free space loss (dB) = 32.44 + 20 log f (MHz) + 20 log d (km)

So, difference in power due to signal frequency is:

20 log (DVB-H frequency) - 20 log (DMB frequency)

and subtracting logarithms is the same as dividing:

20 log (500 / 200)

Difference = 8.0 dB

------------------------------------------------------------------------

Building Penetration Loss

As mentioned earlier, the building penetration loss for 200 MHz relative
to 500 MHz is 3.1 dB

------------------------------------------------------------------------

Overall Difference

Adding up all the differences, using positive numbers for DVB-H at 500
MHz being higher, and negative numbers for DMB at 200 MHz being higher:

Antenna gain = -4 dB
Required C/N = -0.9 dB
Signal bandwidth = +7 dB
Signal frequency = + 8 dB
Building penetration loss = -3.1 dB

Overall total = +7.0 dB

and 7 dB is equivalent to the transmitter powers being 5 times higher.

Olivier, you claimed that DVB-H requires 30 dB higher transmitter powers
than DMB. You are now incorrect by 23 dB, which means that you are
incorrect by a factor of 200!!!!!!!!!!!!!!

And just look at what you get for increasing the transmitter powers:

Multiplex Capacities

DMB using PL3A multiplex capacity = 1.091 Mbps
DVB-H using 16-QAM, code rate of 1/2, multiplex capacity = 7.46 Mbps

A DVB-H MULTIPLEX CARRIES SEVEN TIMES AS MUCH DATA AS A DMB MULTIPLEX.


Overall Conclusion:

DVB-H is a vastly superior mobile digital communication system to DMB.




--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

Find the cheapest Freeview, DAB & MP3 Player Prices:
http://www.digitalradiotech.co.uk/freeview_receivers.htm
http://www.digitalradiotech.co.uk/dab_digital_radios.htm
http://www.digitalradiotech.co.uk/mp3_players_1GB-5GB.htm
http://www.digitalradiotech.co.uk/mp3_players_large_capacity.htm

DAB sounds worse than FM wrote:

Olivier Boudot wrote:

<snip>

Yesterday, you said that I lacked experience on the ground, and
criticised me for not listening to people whom you presumably consider
understand this subject better than myself.

Also yesterday, you claimed that DVB-H required 30 dB higher
transmitter powers than DMB. I have accounted for 10 dB out of the 30
dB, but this 10 dB higher transmitter power allows DVB-H to carry 7
times the capacity that DMB can carry.

Question: where is the remaining 20 dB out of the 30 dB that you
claim?

Additional Information:

Quoting from Wireless Communications, Principles & Practice, by T.S.
Rappaport, sub-section 3.12 Signal Penetration into Buildings, pages
131-132:

"Measurements in Liverpool [Tur 87] showed that penetration loss
decreases with increasing frequency. Specifically, penetration
attenuation values of 16.4 dB, 11.6 dB and 7.6 dB were measured on the
ground floor of a building at frequencies of 441 MHz, 896.5 MHz, and
1400 MHz, respecitvely."

And interpolating these figures to 200 MHz and 500 MHz you would get
penetration losses of:

200 MHz: 18.9 dB
500 MHz: 15.8 dB

In other words, a difference of 3.1 dB

Factors that influence differences in transmitter powers for the same
reception environments (e.g. coverage for indoor reception requires the
highest transmitter powers) are as follows:

* antenna gain
* required C/N
* signal bandwidth
* signal frequency
* building penetration loss


Antenna Gain:

Antenna gain is proportional to the length of the antenna up until the
length equals half a wavelength, i.e. a dipole.

Assuming a mobile phone antenna with a 7 cm long integrated antenna, the
antenna gains are as follows:

At 200 MHz:

antenna gain = 10 log (0.07 / 0.75) = -10.3 dB

At 500 MHz:

antenna gain = 10 log (0.07 / 0.3) = -6.3 dB

Difference = 4 dB higher power required for DMB in Band III

-----------------------------------------------------------------------

Required C/N

DMB using PL3A: 16 dB (quoted from Digital Audio Broadcasting,
Principles & Applications)

DVB-H using 16-QAM, inner code rate of 1/2: 15.1 dB (quoted from DVB-H
Implementation Guidelines, ETSI TR 102 377)

Difference = 0.9 dB higher for DMB

------------------------------------------------------------------------

Signal Bandwidth

The difference is simply:

10 log (DVB-H OFDM bandwidth / DMB OFDM bandwidth)

For an 8 MHz DVB-H channel:

Difference = 10 log (7.64 / 1.536)

Difference = 7.0 dB higher for DVB-H

------------------------------------------------------------------------

Signal Frequency

Quoting the free space loss equation:

Free space loss (dB) = 32.44 + 20 log f (MHz) + 20 log d (km)

So, difference in power due to signal frequency is:

20 log (DVB-H frequency) - 20 log (DMB frequency)

and subtracting logarithms is the same as dividing:

20 log (500 / 200)

Difference = 8.0 dB

------------------------------------------------------------------------

Building Penetration Loss

As mentioned earlier, the building penetration loss for 200 MHz relative
to 500 MHz is 3.1 dB

------------------------------------------------------------------------

Overall Difference

Adding up all the differences, using positive numbers for DVB-H at 500
MHz being higher, and negative numbers for DMB at 200 MHz being higher:

Antenna gain = -4 dB
Required C/N = -0.9 dB
Signal bandwidth = +7 dB
Signal frequency = + 8 dB
Building penetration loss = -3.1 dB

Overall total = +7.0 dB

and 7 dB is equivalent to the transmitter powers being 5 times higher.

Olivier, you claimed that DVB-H requires 30 dB higher transmitter powers
than DMB. You are now incorrect by 23 dB, which means that you are
incorrect by a factor of 200!!!!!!!!!!!!!!

And just look at what you get for increasing the transmitter powers:

Multiplex Capacities

DMB using PL3A multiplex capacity = 1.091 Mbps
DVB-H using 16-QAM, code rate of 1/2, multiplex capacity = 7.46 Mbps

A DVB-H MULTIPLEX CARRIES SEVEN TIMES AS MUCH DATA AS A DMB MULTIPLEX.


Overall Conclusion:

DVB-H is a vastly superior mobile digital communication system to DMB.




--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

Find the cheapest Freeview, DAB & MP3 Player Prices:
http://www.digitalradiotech.co.uk/freeview_receivers.htm
http://www.digitalradiotech.co.uk/dab_digital_radios.htm
http://www.digitalradiotech.co.uk/mp3_players_1GB-5GB.htm
http://www.digitalradiotech.co.uk/mp3_players_large_capacity.htm

DAB sounds worse than FM wrote:

<snip>

Required C/N

DMB using PL3A: 16 dB (quoted from Digital Audio Broadcasting,
Principles & Applications)

DVB-H using 16-QAM, inner code rate of 1/2: 15.1 dB (quoted from DVB-H
Implementation Guidelines, ETSI TR 102 377)

Difference = 0.9 dB higher for DMB

And, of course, DVB-H can use modes that require lower C/N:

QPSK code rate 1/2: required C/N = 9.6 dB (from DVB-H Implementation
Guidelines)
QPSK code rate 2/3: required C/N = 12.6 dB ( " "
" " )

------------------------------------------------------------------------

Overall Difference

Adding up all the differences, using positive numbers for DVB-H at 500
MHz being higher, and negative numbers for DMB at 200 MHz being
higher:
Antenna gain = -4 dB
Required C/N = -0.9 dB
Signal bandwidth = +7 dB
Signal frequency = + 8 dB
Building penetration loss = -3.1 dB

Overall total = +7.0 dB

Overall difference for DVB-H QPSK code rate 1/2 = +7 - (15.1 - 9.6) =
+1.5 dB
Overall difference for DVB-H QPSK code rate 2/3 = +7 - (15.1 - 12.6) =
+4.5 dB

Multiplex capacity for DVB-H QPSK code rate 1/2 = 3.735 Mbps
Multiplex capacity for DVB-H QPSK code rate 2/3 = 4.98 Mbps

DMB multiplex capacity using PL3A = 1.091 Mbps

Overall
--------

+1.5 dB transmitter power provides 3.735/1.091 = 3.4 times as much data
capacity
+4.5 dB transmitter power provides 4.98/1.091 = 4.56 times as much data
capacity
+7.0 dB transmitter power provides 7.46/1.091 = 6.84 times as much data
capacity

And:

DVB-H using QPSK code rate 1/2 only requires 1.5 dB extra transmitter
power compared to DMB, which means your prediction that DVB-H requires
30 dB higher transmitter powers is incorrect by 28.5 dB, or incorrect by
a factor of 709.

DVB-H using QPSK code rate 2/3 only requires 4.5 dB extra transmitter
power compared to DMB, which means your prediction that DVB-H requires
30 dB higher transmitter powers is incorrect by 25.5 dB, or incorrect by
a factor of 355.

DVB-H using 16-QAM code rate 1/2 only requires 7 dB extra transmitter
power compared to DMB, which means your prediction that DVB-H requires
30 dB higher transmitter powers is incorrect by 23 dB, or incorrect by a
factor of 200.

Did you pass your maths exams at school?


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

Find the cheapest Freeview, DAB & MP3 Player Prices:
http://www.digitalradiotech.co.uk/freeview_receivers.htm
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http://www.digitalradiotech.co.uk/mp3_players_large_capacity.htm

DAB sounds worse than FM wrote:

<snip>

Required C/N

DMB using PL3A: 16 dB (quoted from Digital Audio Broadcasting,
Principles & Applications)

DVB-H using 16-QAM, inner code rate of 1/2: 15.1 dB (quoted from DVB-H
Implementation Guidelines, ETSI TR 102 377)

Difference = 0.9 dB higher for DMB

And, of course, DVB-H can use modes that require lower C/N:

QPSK code rate 1/2: required C/N = 9.6 dB (from DVB-H Implementation
Guidelines)
QPSK code rate 2/3: required C/N = 12.6 dB ( " "
" " )

------------------------------------------------------------------------

Overall Difference

Adding up all the differences, using positive numbers for DVB-H at 500
MHz being higher, and negative numbers for DMB at 200 MHz being
higher:
Antenna gain = -4 dB
Required C/N = -0.9 dB
Signal bandwidth = +7 dB
Signal frequency = + 8 dB
Building penetration loss = -3.1 dB

Overall total = +7.0 dB

Overall difference for DVB-H QPSK code rate 1/2 = +7 - (15.1 - 9.6) =
+1.5 dB
Overall difference for DVB-H QPSK code rate 2/3 = +7 - (15.1 - 12.6) =
+4.5 dB

Multiplex capacity for DVB-H QPSK code rate 1/2 = 3.735 Mbps
Multiplex capacity for DVB-H QPSK code rate 2/3 = 4.98 Mbps

DMB multiplex capacity using PL3A = 1.091 Mbps

Overall
--------

+1.5 dB transmitter power provides 3.735/1.091 = 3.4 times as much data
capacity
+4.5 dB transmitter power provides 4.98/1.091 = 4.56 times as much data
capacity
+7.0 dB transmitter power provides 7.46/1.091 = 6.84 times as much data
capacity

And:

DVB-H using QPSK code rate 1/2 only requires 1.5 dB extra transmitter
power compared to DMB, which means your prediction that DVB-H requires
30 dB higher transmitter powers is incorrect by 28.5 dB, or incorrect by
a factor of 709.

DVB-H using QPSK code rate 2/3 only requires 4.5 dB extra transmitter
power compared to DMB, which means your prediction that DVB-H requires
30 dB higher transmitter powers is incorrect by 25.5 dB, or incorrect by
a factor of 355.

DVB-H using 16-QAM code rate 1/2 only requires 7 dB extra transmitter
power compared to DMB, which means your prediction that DVB-H requires
30 dB higher transmitter powers is incorrect by 23 dB, or incorrect by a
factor of 200.

Did you pass your maths exams at school?


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

Find the cheapest Freeview, DAB & MP3 Player Prices:
http://www.digitalradiotech.co.uk/freeview_receivers.htm
http://www.digitalradiotech.co.uk/dab_digital_radios.htm
http://www.digitalradiotech.co.uk/mp3_players_1GB-5GB.htm
http://www.digitalradiotech.co.uk/mp3_players_large_capacity.htm

François Guillet a écrit :

"Olivier Boudot" <oboudotspam@freeaol.com> a écrit dans le message de news:
Xns966191B0BB6FBoboudotspamfreeaol@212.27.42.78...
| "DAB sounds worse than FM"
|
| Aïe... Je me disais bien que la peste finirait bien un jour pas s'abattre
| sur le bas clergé breton ;-). Plus prosaïquement, mes craintes sont que ce
| NG, au ton particulièrement constructif pour un NG usenet, ne tombe dans
| les affres de son homologue britannique, alt.radio.digital ,
| potentiellement illisible du fait de son envahissement par les
| élucubrations fort envahissantes de cet individu. ...

En tout cas d'un point de vue technique, il connaît son affaire, il n'a pas
dit de conneries, c'est même instructif car il donne beaucoup de références.

fg

Peut être mais c'est un NG en FRANCAIS !!!