Hi all
thanks again for precious help,
I’ll soon start working on code cleaning and optimization for real time
performance of my Gnuradio DVB Tx.
here is a video showing latest improvements in transmitted signal…
http://wwvince.interfree.it/Soft-DVB
h264 video as usual
Best Regards
vincenzo
ps
Matt …is the VHF/UHF frontend release date confirmed somewhere around
January?
Thanks
Vincenzo,
I took a look at the video. Very cool work! If I understand correctly,
you are showing gnuradio + your code generating DVB in real time, and
transmitting it with a USRP over coax to a set top box for receiving
DVB. Is that right?
The 50 MHz to 1 GHz transceiver daughterboard should be available in
late February.
For those who are having trouble viewing it on linux, the video plays
for me with mplayer and xine.
Matt
Soft-DVB working flawlessly …
thanks again for precious help,
Thank you for building a great tool on top of all the signal
processing work that’s been poured into GNU Radio over the years.
We hoped someone like you would do things like this!
I’ll love to see it GUI’d and packaged so that anybody can make a
local DVB transmission station by just plugging the hardware together,
installing the right software package, and feeding it realtime video
streams. Has anyone glued GRC into MythTV?
I can already think of one use that others can make of your
transmitter. EFF and I are interested in measuring the DRM responses
of various digital television consumer products. DRM is the
unnecessary restrictions that are built in to control what consumers
can do. (Like no fast forwarding; won’t play in some countries; or
only works with one manufacturer’s products.) DVB is really thick
with complicated, ugly restrictions like “can only record one copy –
only on Tuesdays and only within 1000 meters or with members of your
immediate family except for kids of divorced parents”. I bet there is
a lot of variation in the products that try to enforce it – and maybe
some don’t even try.
Manufacturers tend to avoid documenting these ‘features’, for some
reason. We consumers can benefit by collectively reverse-engineering
what they are up to. In particular, nobody should be buying DRM-laced
products without knowing it, when similar non-DRM products would serve
the consumer as well or better. But how can we tell them apart? A
broadcast-quality software transmitter for DVB (and for ATSC and other
dtv waveforms) would let us do these tests. (We’ll also need a simple
editor for MPEG transport streams, for inserting and removing
“Broadcast Flags” and other data items.)
John G.
2007/11/22, Teun van Berkel [email protected]:
Hi Vicenzo,
first of all, great work, the video really looks cool. Just a couple
of questions.
thanks
You have build a DVB-t transmitter, right?
yup
The video you are
transmitting (The soccer video), is that stored on your local
harddrive?
it comes from an MPEG2 transport stream which was captured when we
(Italy)
won the 2006 WorldCup
the ts is just the input to my modulator which is entirely implemented
in
software,baseband samples for the consequent OFDM signal are calculated
(not
yet in real time, but it is achievable) and then sent out for the usrp
to
make them a real world signal, and place it where it is due in the UHF
spectrum.
Or did you receive a local DVB-t signal and converted it to
a different frequency before transmitting it again? it is a bit
unclear to me how where you get your video source from.Are you using the DVB-t setting with roughly 8000 subcarriers? Is it
no it is a 2K for now
still possible to do an IFFT with this many subccariers real-time? My
guess would be that this is the limited factor for real-time
transmission.Really hope you could answer these questions,
Thanks,
you’re welcome
Teun van Berkel
vincenzo
John G. schrieb:
some don’t even try.
Those ‘family’ options will only be available after having you and yours
updated (apparently evolution never
thought of that option…) with intracranial RFID chips…
But that aside… having the ability to do DVB would then allow one to
modify the signal with the idea of
simulating various distortions that occur in broadcast… is there an
ATSC 8VSB modulator?
John C…
Quoting John C. [email protected]:
John G. schrieb:
I can already think of one use that others can make of your
transmitter. EFF and I are interested in measuring the DRM responses
I am interested in a dvb-s receiver, but if I understand correctly
most open/free satellite transponders are wider than our current 8MHz
bandwidth.
http://www.lyngsat.com/freetv/United-States.html
–Chuck
Vincenzo P. schrieb:
code will be not just working but also clean and quick, I’ll start a
proper contribution procedure…
While in the recent past most of my interest has been directed to the US
DTV… I would like to see
DVB-T for the future…
John C…
Hi,
sorry I just have DVB-T at the moment…
for John G., I have just seen your email in GNURadio archive.
For some strange reason i had missed it. Really thanks for your words of
enthusiastic appreciation.
Currently I’m cleaning the code with the purpose of approaching
real-time on my current sempron-based single core pc. As soon as the
code will be not just working but also clean and quick, I’ll start a
proper contribution procedure… 
best regards
vincenzo
On Mon, Nov 26, 2007 at 11:18:53AM -0700, Chuck Swiger wrote:
Quoting John C. [email protected]:
John G. schrieb:
I can already think of one use that others can make of your
transmitter. EFF and I are interested in measuring the DRM responsesI am interested in a dvb-s receiver, but if I understand correctly
most open/free satellite transponders are wider than our current 8MHz
bandwidth.
Yes, and no. Most signals you might be interested in are, but
not all … there are lots and lots of SD DSNG signals from satellite
news trucks with symbol rates around 3978.7 Ksym/sec (a standard for a
5.5 Mbs transport stream with 3/4 FEC) and a few other rates near that
in use. These signals should be narrow enough to work with the USRP.
I am hoping the USRP II will have the resources to do full
transponder DVB-S and DVB-S2 stuff in some mode or another - there is
definately a need for this for signal analysis/transponder IDing…
–
Dave Emery N1PRE/AE, [email protected] DIE Consulting, Weston,
Mass 02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
‘For Rent’ sign still vainly flapping outside on the weed encrusted pole
Dave schrieb:
I can think of another as well… maybe you’ll consider this, even if
it’s still some time away from being widely implemented…As some of you (e.g. those in the San Francisco Bay Area) may already
be aware, the electrical power company here (PG&E, or Pacific Gas &
Electric) is now beginning to beta-test a “SmartMeter™” on 8,500 San
Francisco homes and businesses [1].
I think the basic reason why people are so accepting of these sorts of
things, are 1) They don’t care as long as their cable feed is up…
2) think along the lines of ‘Well, I’m not doing anything bad, so really
why should I worry’… until one of them ends up with a bill from
the recording industry for copyright infringements because they were
playing their neighbor’s iPod in their house…
On how to deal with such snoopage, perhaps GNURadio could be used
monitor and then to inject a small amount of ‘noise’ in to the line to
‘cover’
any residuals picked up by the line in the house.
John C…
On Tue 20 Nov 2007, at 11:07 PM, John G. wrote:
Soft-DVB working flawlessly …
thanks again for precious help,Thank you for building a great tool on top of all the signal
processing work that’s been poured into GNU Radio over the years.
We hoped someone like you would do things like this!
I second that!
Sidenote: I’d also like to thank Firas for his first approach at
documentation. With due respect to everyone doing all this great work
with GNU Radio, this signals the beginning for the rest of us (non-
radio engineers) to begin to understand and fully appreciate its
significance. Who knew, after that first meeting in Fry’s
Electronic’s cafe, that the project would take off in this great way. 
… I can already think of one use that others can make of your
transmitter. EFF and I are interested in measuring the DRM responses
of various digital television consumer products. …
That’s an excellent idea, John.
I can think of another as well… maybe you’ll consider this, even if
it’s still some time away from being widely implemented…
As some of you (e.g. those in the San Francisco Bay Area) may already
be aware, the electrical power company here (PG&E, or Pacific Gas &
Electric) is now beginning to beta-test a “SmartMeter™” on 8,500 San
Francisco homes and businesses [1].
After years of development (involving close work with the EPRI, or
Electric Power Research Institute, a power industry consortium of
large utility corporations), PG&E has selected a new type of electric
power meter from SmartSynch, Inc. [2] that can wirelessly transmit
massive amounts of data about your building’s electrical usage to a
radio receiver nearby in your neighborhood. From those base stations,
the data is sent over an “advanced communications network” (meaning
fractional T1?). Although PG&E has “no plan to utilize the device’s
real-time capabilities”, the feature is nevertheless fully present in
the beta devices… it is “just not turned on”, according to a semi-
trained SmartMeter representative I spoke with, the feature is
nevertheless fully present in the beta devices… it is “just not
turned on”. Of course, we all know how terribly trustworthy and super-
civic-minded these power companies are, right?
Some of you may already be familiar with the privacy and security
issues regarding wired home power circuits. Using current wired power
lines, an entity with sufficient access to a building’s wiring could
determine (with considerable accuracy) what people are doing inside
by tracking the voltage spikes of devices (e.g. appliances) plugged
into the wall. These days, this means virtually everything in the
house, including Japanese electronic toilets, kitchen refrigerators,
corded “massagers”, bedside lamps and clock-alarms, etc. You get the
idea. Security researchers as far back as the 80’s described and
later demonstrated TEMPEST-like surveillance capabilities, using
devices built from common off-the-shelf parts, that could extract a
viewable monochrome image of a computer display device (any type, not
just CRTs) anywhere on a building’s power circuit, after picking it
out of all of the other devices by progressively “tuning in” to
characteristic voltage patterns [3]. When “home ethernet over
electric power wire” kits recently became popular for retrofitting
networks in older buildings, new attacks on your home network
connection became possible [4].
Soon, enormous quantities of power metering data will be broadcast
wirelessly.
Because it is so “convenient” for Customers (they couldn’t really
explain to me how, yet they used that word), PG&E expects to install
these SmartMeters on nearly every urban structure in California
within 5 years. Where California goes, so goes the rest of the US.
Within 10-20 years, as the manufacturing and installation costs fall
(economies of scale) and the technology is transferred to other
countries, it is reasonable to imagine that SmartMeters will become
extremely common worldwide. Imagine all of that fine-grained power-
use data, broadcast into the air 24/7/365. Now, though the technical
security specifications are unavailable (or “coming soon” [5])
considering the complexity of the PKI (public key infrastructure)
that would be involved for the encryption, you can probably imagine
how unenthusiastic the power companies are about implementing a
robust security infrastructure for these transmissions… what a
headache for their IT departments, right? On the other hand, the
world’s intelligence agencies must be absolutely drooling with
anticipation… it’s a magical backdoor into Everything that is so
“transparent” that hundreds of millions of power consumers will never
give it a second thought.
Perhaps a GNU Radio tool for interacting with the wireless signals
from SmartMeters (and similar devices) might make it possible to
better protect people from unwarranted intrusions into their private
lives by:
* Sniffing the data, i.e. for auditing and/or analysing what
data the
power companies are extracting from your meter, just to “keep
them honest”,
* Selectively suppressing the signal and aggregating the data
(so that,
e.g. it could only broadcast a total power usage number at
midnight
on one night every month (allowing the power company access to
only the data required for billing purposes, just like they
used to
have),
* Preventing interference with cellular/handheld telephones,
pacemakers,
digital television broadcasts, etc by …attenuating or
jamming the
signal close to the source? (if this is even technically
feasible
with radio without making the interference worse…)
* Forcing open source encryption of the signal to the
neighborhood base
station to encourage the power company to implement security
measures that place the PKI control in the hands of the
consumers,
* Mixing random data in with the signal to, e.g., make every
device in
the house appear to randomly turn on for a few seconds at
intervals
of a few minutes (while preserving the total usage numbers
so there
is no fraud), effectively preventing analysis of the
individual
device usage in your home,
* Piggybacking on the transmission capability to build large ad hoc
wireless networks for free neighborhood TOR networks between
houses, and…
* Other creative uses?
Comments or additional ideas are most welcome.
dave
Dave Del Torto, CSO +1.415.333.3003
CryptoRights Foundation, Inc. (501c3) cryptorights.org
“Securing human rights worldwide, one bit at a time.”
…
[1] http://www.pge.com/smartmeter/
[2] http://www.smartsynch.com/
[3] http://jya.com/emr.pdf
[4] <http://reviews.cnet.com/bridges/siemens-speedstream-powerline-
ethernet/4505-3304_7-20684584.html>
[5] http://www.smartsynch.com/support/tech_library.html
Dave wrote:
semi-trained SmartMeter representative I spoke with, the feature is
nevertheless fully present in the beta devices… it is “just not
turned on”. Of course, we all know how terribly trustworthy and
super-civic-minded these power companies are, right?
Hello,
A sizable utility like PG&E needs a good data network for their SCADA
system. This is used for distributed metering and control at the
transmission line level and employs Microwave and/or Fiber. The Fiber
is usually run along the transmission line right-of-way. Utilites
usually own and maintain their communications networks.
Power Line Carrier is used for low speed data. It is basically Low
Frequency Radio Waves coupled directly to the transmission line. Older
systems used on-off keying while newer systems use PSK.
A brief search shows PG&E uses fiber and offers their excess capacity
for sale as some other utilities are doing. Some utilities are also
looking into becoming ISPs by deploying a Broadband over power lines
(BPL) system,.
From what I heard about SmartMeters they extend SCADA functions down to
the distribution level. I could see utiliies having the wireless
receivers at substations and using their fiber to get it back to the
central servers. I mainly deal with the Protective Relaying part of the
industry so I am more familiar with electric utility communications that
support the System Fault Protection part. The few large utilities I
have talked to do take network security seriously.
The security threat posed to you in your home depends on what is meant
by real-time. Typically the meter in a house measures the power you use
in watt-hours. The real-time function may just be a direct reading of
the voltage and current on a per cycle basis much like a regular AC
Voltmeter and AC Ampmeter. I would be more concerned if the device has
DFR (Digital Fault Recorder) functions that can sample many points on
the AC waveform and send it back over SCADA. The sampling rates
generally go up to 200 KSPS.
http://preview.ametek.com/content-manager/files/pip/2100736.pdf
I am not familiar with the sampling rates needed to reconstruct computer
monitor output.
A DFR is handy if a transmission line fault occurs and the fault
protection does not operate properly. It is possible to playback the
fault recording from the DFR records and test the fault protection.
I work for a company that makes test equipment for the power industry.
It is a private company in the process of being sold to the holding
company that owns DCSI. DCSI is involved with SmartMeters.
http://tdworld.com/customer_service/power_smartmeter_program_deployment_2/
73 Eric
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