Hi, 

 

The Us are when I do something else with the machine. They do not show when I 
keep my fingers off the mouse, so no reason to worry, it runs for ages without 
a single U when the machine is kept alone. 

 

I already found out about the rate. The coding also needs to be reflected by 
the transport stream, or just regarding the bitrate? I did not find a setting 
for that, but I will look deeper into it during the next days, when I find some 
time. My first test trying to set identical settings like from the working test 
stream brought just a black picture. 

 

Another question...when looking into the constellation, what are the two dot 
clouds on the X/I-axis, outside the expected 4*4 cloud matrix? Some embedded 
BPSK? I could not find this in the DVB-T specs at first glance...

 

Ralph.

 

 

From: Bogdan Diaconescu [mailto:b_diacone...@yahoo.com] 
Sent: Wednesday, April 8, 2015 2:57 PM
To: Ralph A. Schmid, dk5ras; 'Ron Economos'; discuss-gnuradio@gnu.org
Subject: Re: [Discuss-gnuradio] DVB-T/T2

 

Hi Ralph,

 

DVB-T.png shows some u's on the command line which means the whole flowgraph do 
not provide data to USRP at the right speed. It basically mean the computer 
cannot cope with the required processing requirement.

 

As for the video parameters, in the DVB-T specs 
(http://www.etsi.org/deliver/etsi_en/300700_300799/300744/01.06.01_60/en_300744v010601p.pdf)
 you will find Table 17 where the rates are presented. FYI, the settings you 
have used are 8Mhz bandwidth, QAM-16 constellation, coding 1/2, guard interval 
1/32. The video should be constant bit rate but it is not a hard requirement 
(see below).

 

If you just broadcast video from a file and not plan to use a live streaming 
from camera, the rate should not matter too much. The video is sent at the rate 
of the DVB-T according to it's parameters and with RTL2832 receiver it is 
buffered and played at the correct speed (at least for short files like 
test.ts).

 

Bogdan

 

 

On Wednesday, April 8, 2015 11:55 AM, "Ralph A. Schmid, dk5ras" 
<ra...@schmid.xxx <mailto:ra...@schmid.xxx> > wrote:

 

Yep, this would be quite useful!

Bogdan, as you are here, too - I don't know very much about all the crazy video 
file stuff, but maybe you can give me some basic parameters I need to comply 
with for a transport stream, to be able to transmit it with your package?! I 
need to use Windows for the conversion, as my Linux installation is only on a 
virtual machine, with limited space and power. A capable looking Windows 
program is available, but there are so many options I have no clue about :(

 

I modified your flow graph according to Rons hints, and now I have a stable and 
reliable DVB-T transmission path with your package. See 
http://dk5ras.dyndns.org/tmp/DVB/ with a screenshot. I am using the Ettus B210, 
and for reception a second PC with DVB-T stick, or a DVB-x tester that does 
them all, DVB-C/S/S2/T/T2. 

 

You and Ron really did a great job with coding those DVB-x packages!

 

Ralph.

 

From: discuss-gnuradio-bounces+ralph=schmid....@gnu.org 
<mailto:discuss-gnuradio-bounces+ralph=schmid....@gnu.org>  
[mailto:discuss-gnuradio-bounces+ralph=schmid....@gnu.org] On Behalf Of Bogdan 
Diaconescu
Sent: Wednesday, April 8, 2015 8:01 AM
To: Ron Economos; discuss-gnuradio@gnu.org <mailto:discuss-gnuradio@gnu.org> 
Subject: Re: [Discuss-gnuradio] DVB-T/T2

 

Ok, it would be useful to have receivers too like for the DVB-T. 

 

Bogdan

 

 

On Tuesday, April 7, 2015 11:23 PM, Ron Economos <w...@comcast.net 
<mailto:w...@comcast.net> > wrote:

 

Only transmitter implementations for now. They are here:

https://github.com/drmpeg/gr-dvbs2

https://github.com/drmpeg/gr-dvbt2

The DVB-T2 implementation supports T2-Lite, tone reservation PAPR reduction and 
MISO processing.

Ron

On 04/07/2015 06:38 AM, Bogdan Diaconescu wrote:

Hi Ron,

 

I have not followed the development of DVB-T2/S2 lately. Are there receiver 
implementations for the T2/S2 or just transmitters?

 

Thanks,

Bogdan

 

 

On Tuesday, April 7, 2015 1:32 PM, "Ralph A. Schmid, dk5ras"  
<mailto:ra...@schmid.xxx> <ra...@schmid.xxx> wrote:

 

Great to hear that you work finds its way into the official thing! 

 

At the moment, as the RF stuff works, I am trying to learn about all this crazy 
video file stuff, for being able to create transport streams with my own 
content. Up to now I am still testing with the cartoon .ts :) Still my laptop 
(with DVBViewer software) will not decode the audio, while the DVB tester 
decodes audio just fine. 

 

Ralph.

  

 

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