Detecting spectrum holes

hi
i’m new to this ,i need your help on how to start detecting spectrum in
TV
band and holes in this spectrum.

The equipments i have

1-2xUSRP-1 PKG(one as RX and the other as TX)
2-WBX
3-RFX2400
4-TVRX
5-DBRX

ANTENNAS

1-LP0410
2-LP0926

2xlaptops with Ubuntu 10.04 with gnuradio and i tested it successfully.

is there any thing missing?

Abdelrahman A.
Communication and electronics Department
final semester
Arab Academy for science and technology and maritime transport

On Sun, Mar 18, 2012 at 12:13 AM, Abdelrahman A.
[email protected]wrote:

5-DBRX
Abdelrahman A.
Communication and electronics Department
final semester
Arab Academy for science and technology and maritime transport

I think you’re starting on the right path.

Tom

2012/3/18 Tom R. [email protected]

3-RFX2400
is there any thing missing?
Tom

hii, again
is there pre coded examples to detect the holes in spectrum?

On 01/-9/-28163 03:59 AM, Abdelrahman A. wrote:

i’m new to this ,i need your help on how to start detecting spectrum
in TV band and holes in this spectrum.

Ahmed,

though others will probable be able to give you more in-depth directions
wrt spectrum sensing, just out of curiosity, what’s your use case?

Are you looking into TV white spaces? [1]

Most likely you’ll want to use the USRP1 with WBX because I assume it
has better sensitivity than TVRX.

Why would you want to transmit anything if you’re just looking into
analyzing spectrum usage in TV channels?

LP0410 is covering the right frequency band for UHF (400 MHz to 1 GHz),
but it is a directional antenna. Is that what you want? Otherwise, you
might be better off using an omni antenna, preferably on a roof…

Here are a few pointers to papers on TV white spaces:

http://www.openspectrum.eu/drupal6/node/23

I’ve posted some of the key issues on this list two years ago:

http://www.ruby-forum.com/topic/205328

Dyspan has some nice papers on spectrum sensing as well:

http://www.ieee-dyspan.org/2010/

Now to the setup:

Hardware / sample data

I have a USRP1, two WBX, USRP1 N210 and an PC hardware available as
well, so unless you’re in a closed source / NDA environment, we could
set up a code repository on github, and I could provide you with sample
recordings from Hong Kong to cross-check detectors.

Regulatory environment / signals too look for

What is your location? From your signature, I assume you’re in the
Middle East, and I guess we’re talking mostly about DVB-T signals. Is
there still analog TV transmission around, wireless microphones, …?

gnuradio packages on Ubuntu

The gnuradio packages that come with Ubuntu 10.04 are most likely a bit
outdated, so you might want to upgrade your laptops to 11.10 first.

10.04 contains 3.0.4-2ubuntu1
(http://packages.ubuntu.com/hardy/gnuradio)
11.10 contains 3.2.2.dfsg-1ubuntu7
(http://packages.ubuntu.com/oneiric/gnuradio)

Once you’ve got 11.10 with the latest packages installed, you might want
to test your setup with some of the gnuradio examples, like a basic FM
receiver to tune in a local radio station.

Hope this helps for a start - please let us/me know on the mailing list
if you need more input :slight_smile:

Alex

[1] White spaces (radio) - Wikipedia

2012/3/19 Alexander L. [email protected]

wrt spectrum sensing, just out of curiosity, what’s your use case?

Are you looking into TV white spaces? [1]

Most likely you’ll want to use the USRP1 with WBX because I assume it has
better sensitivity than TVRX.

Why would you want to transmit anything if you’re just looking into
analyzing spectrum usage in TV channels?

White space sensing efforts - GNU Radio - Ruby-Forum

to test your setup with some of the gnuradio examples, like a basic FM
receiver to tune in a local radio station.

Hope this helps for a start - please let us/me know on the mailing list if
you need more input :slight_smile:

Alex

[1] White spaces (radio) - Wikipedia

hi ,
problem 1

i pugged usrp into usb and run usrp_fft.py and i got signal like noise
it’s
amplitude -60 dB.
i also can run usrp_spectrum_sense.py but only numbers of frequencies
appeared below each other (min freq and max freq).

problem 2

when i plugged out usrp from usb and run usrp_fftw.py again it told me
that can not open usrp.
and when i try benchmark_tx.py and benchmark_rx.py on the other lap,
there
is an error appeared told me that
can not find module usrp_transmit_path

problem 3

  • when i write usrp_probe i can not get any info about my usrp1.
  • when i write uhd_find_devices it told me that:

Could not locate USRP1 firmware

Please install the images package

so from these problems some programs can identify the usrp1 and the
other not, so what is happening here.

Abdelrahman ahmed

egypt,cairo

arab academy for science and technology and maritime transport

On 21/03/12 11:25 PM, John Ewan wrote:

Oh, I think we all know what is meant by “spectrum holes”, even though
they don’t really exist in the physical
world. But any energy entering your receiver that is significantly
below the equivalent noise temperature of
the receiver would be counted as a “hole”–there may be something
there, but it’s too weak to matter–modulo
schemes that place the instantaneous energy below the “noise floor”,
like certain types of CDMA systems.

And with the magic of integration, you can detect the presence of
“signals” that are well below the noise
temperature of your receiver. Which is how radio astronomy works.

but it is a directional antenna. Is that what you want? Otherwise, you
Dyspan has some nice papers on spectrum sensing as well:
so unless you’re in a closed source / NDA environment, we could set up a

========
is an error appeared told me that


Discuss-gnuradio mailing list
[email protected]
Discuss-gnuradio Info Page


Principal Investigator
Shirleys Bay Radio Astronomy Consortium

I have had enough about this. What the heck is a spectrum hole.
I am pretty sure this is probably a term brought up by some…

There are NO spectrum holes. Learn about black body radiation
and KTB…

Sorry folks. the term has always erked me.

We can talk about white space…that I can take.

John,

may I ask you to be a bit more patient with GNU Radio beginners in general, and in particular with those whose mother tongue is not English? On top of that, the tiny hairs on my spine just got triggered, and that's caused by an adrenaline rush in reaction to potentially rude language ;)

Back to the facts:

Google has 32.1 million hits for “spectrum hole”, and about every second
one on the first page seems to be an academic paper. So maybe some …
defined the term, but this won’t change the fact that it’s used in real
life, even by academics. Your point reminds me of my physics teacher
complaining that we shouldn’t use the term “weight” together with
kilograms, because kilogram is the unit of mass and weight is measured
in Newton. You will never get rid of colloquial language entirely.

Can we please get back to a constructive discussion now and help Ahmed
with his problem?

@Ahmed:

Problem 1: Please describe your hardware setup so that we can help:

a) What USRP model are you using? What GNUradio version, did you install
the distribution package on Ubuntu 8.04 or upgrade to 11.10 as
suggested? What was the exact command line you used for
usrp_spectrum_sense.py and usrp_fft.py?
b) What daughterboard did you install inside the USRP? How did you
connect it to the USB port of your laptop, and how to the antenna?
c) Is the USRP powering up?
d) After a power cycle (everything just switched on), does
uhd_find_devices still give you nothing? what about lsusb -v?

In case you managed to get up to d) and have the USRP and
daughterboard(s) detected correctly,

e) Did you connect the antenna to the appropriate RX channel of your
daughterboard? When using WBX, there’s an RX and an RX/TX port, so if
you connect the antenna to the wrong port, you might only see noise
except for a few very strong local sources. Try tuning to a local FM
radio station… Any antenna should do for this purpose, even a
paperclip - but don’t torture the gold plated SMA connectors of the USRP
with that :slight_smile:

Problem 3 is probably caused by Problem 2. I also noticed that sometimes
the USB stack seems to get messed up, so you might want to try a) power
cycling your USRP and if that doesn’t help, b) power cycling the laptop
connected to the USRP.

I’m only a beginner myself, but that’s what came to my mind because I
ran into similar issues myself. If this doesn’t help, please make sure
you’re at least on Ubuntu 11.10 and then we can compare results…

cheers

Alex

On Wed, 21 Mar 2012, John Ewan wrote:

I have had enough about this. What the heck is a spectrum hole.
I am pretty sure this is probably a term brought up by some…

There are NO spectrum holes. Learn about black body radiation
and KTB…

A spectrum hole is a part of spectrum nobody can sue you for using.

             best

               Vladimir Dergachev

On Thu, Mar 22, 2012 at 05:18:39PM +0800, Alexander L. wrote:

John,

may I ask you to be a bit more patient with GNU Radio beginners in general, and in particular with those whose mother tongue is not English? On top of that, the tiny hairs on my spine just got triggered, and that's caused by an adrenaline rush in reaction to potentially rude language ;)

Thanks for this, Alexander! Well put.
Besides, what the heck is ‘white’ about ‘white spaces’? :slight_smile:

MB


Karlsruhe Institute of Technology (KIT)
Communications Engineering Lab (CEL)

Dipl.-Ing. Martin B.
Research Associate

Kaiserstraße 12
Building 05.01
76131 Karlsruhe

Phone: +49 721 608-43790
Fax: +49 721 608-46071
www.cel.kit.edu

KIT – University of the State of Baden-Württemberg and
National Laboratory of the Helmholtz Association

MY problem

when i plugged out usrp from usb and run usrp_fftw.py again it told me
Could not locate USRP1 firmware
arab academy for science and technology and maritime transport



Discuss-gnuradio mailing list
[email protected]
Discuss-gnuradio Info Page

c) Is the USRP powering up?
station… Any antenna should do for this purpose, even a paperclip - but
don’t torture the gold plated SMA connectors of the USRP with that :slight_smile:

Problem 3 is probably caused by Problem 2. I also noticed that sometimes
the USB stack seems to get messed up, so you might want to try a) power
cycling your USRP and if that doesn’t help, b) power cycling the laptop
connected to the USRP.

frist of all i have two laptops with ubuntu 11.10 x32bit installed
inside
windows 7 professional x64, i used this link in synaptic to install
gnuradio packages:

11.10 contains 3.2.2.dfsg-1ubuntu7 (
http://packages.ubuntu.com/oneiric/gnuradio)

and this guide to install the other packages :

http://gnuradio.org/redmine/projects/gnuradio/wiki/UbuntuInstall#Install-Dependencies

After successful installation still there is UHD, i installed it through
this:

git clone git://code.ettus.com/ettus/uhd.git

cd uhd/host

mkdir build

cd build

cmake …/

make

make test

sudo make install

#Check where your path is with “find |grep libuhd”

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

after that i checked:

python worked
gnuradio-companion worked
gnuradio worked

so guide me if i mess something or did something wrong in installation
step
?
i will provide you with other information about hw setup and what each
usrp
box contain? in Saturday

On 3/22/12, [email protected] [email protected] wrote:

(http://packages.ubuntu.com/oneiric/gnuradio [1])

export
something or did something wrong in installation step ?
Links:


[1]
http://packages.ubuntu.com/oneiric/gnuradio
[2]

http://gnuradio.org/redmine/projects/gnuradio/wiki/UbuntuInstall#Install-Dependencies

[3]
http://code.ettus.com/ettus/uhd.git

I am curious, why did you not use the the build-gnuradio script here:
http://gnuradio.org/redmine/projects/gnuradio/wiki/InstallingGR

It has everything you need to get started and if you are new to GNU
Radio it does save you a lot of trouble.

-Jon

PS Save yourself some trouble and do a fresh install of Ubuntu on the
hard drive, just make an image of your current hard drive for when you
want to go back to Windows. VMs help make life miserable with this
sort of thing.

On Thu, 22 Mar 2012 15:38:18 +0200, Abdelrahman A. wrote:

frist of all i have two laptops with ubuntu 11.10 x32bit installed
inside windows 7 professional x64, i used this link in synaptic to
install gnuradio packages:

11.10 contains 3.2.2.dfsg-1ubuntu7
(http://packages.ubuntu.com/oneiric/gnuradio [1])

and this guide
to install the other packages :

http://gnuradio.org/redmine/projects/gnuradio/wiki/UbuntuInstall#Install-Dependencies
[2]

After successful installation still there is UHD, i installed
it through this:

git clone git://code.ettus.com/ettus/uhd.git [3]

cd uhd/host

mkdir build

cd build

cmake …/

make

make test

sudo make install

#Check where your
path is with “find |grep libuhd”

export
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib
after that i
checked:

python worked

gnuradio-companion worked

gnuradio worked

so guide me if i mess
something or did something wrong in installation step ?
i will provide
you with other information about hw setup and what each usrp box
contain? in Saturday

USB device performance/reliability inside a VM
from Windows is not good at all, and I’m surprised you can get anything
to work at all this way.

Links:

2012/3/22, Abdelrahman A. [email protected]:

i’m not using VMs at all i just choose install inside windows option
from ubuntu installation menu and i need to reboot to enter ubuntu os
so i think it is not VM

2012/3/22, Jonathan F. [email protected]:

Finding white space in the spectrum can be done by looking at power
across
the bins you are monitoring. I have done White space research with the
USRP2 and the WBX, and they worked out great for me. So you’re on the
right track!

Take a look at this work, Section 3.1:

They have a basic technique for detecting white space. Their paper was
not
about the TV bands, but the technique should work elsewhere.

Best of luck, and welcome!

  • George

On Fri, Mar 23, 2012 at 11:56 AM, Abdelrahman A.
[email protected]wrote:

http://static.usenix.org/event/nsdi10/tech/full_papers/yang.pdf
windows.

mkdir build

#Check where your path is with “find |grep libuhd”

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

i did not do anything else ??

This is an ancient version of Gnuradio. Please use Marcus L.'s
“build-gnuradio” script, available here:

http://www.sbrac.org/files/build-gnuradio

Uninstall your Gnuradio with Synaptic first.

–n

2012/3/23 George N. [email protected]

Best of luck, and welcome!

  • George

ok, now i installed ubuntu from scratch on the two laptops not with
windows.

so is there something missing in this installation :

i used this link in synaptic to install gnuradio packages:

11.10 contains 3.2.2.dfsg-1ubuntu7 (
http://packages.ubuntu.com/oneiric/gnuradio)

and this guide to install the other packages :

http://gnuradio.org/redmine/projects/gnuradio/wiki/UbuntuInstall#Install-Dependencies

After successful installation still there is UHD, i installed it through
this:

git clone git://code.ettus.com/ettus/uhd.git

cd uhd/host

mkdir build

cd build

cmake …/

make

make test

sudo make install

#Check where your path is with “find |grep libuhd”

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

i did not do anything else ??

Alexander L. wrote in post #1052238:

On 01/-9/-28163 03:59 AM, Abdelrahman A. wrote:

i’m new to this ,i need your help on how to start detecting spectrum
in TV band and holes in this spectrum.

Ahmed,

though others will probable be able to give you more in-depth directions
wrt spectrum sensing, just out of curiosity, what’s your use case?

Are you looking into TV white spaces? [1]

Most likely you’ll want to use the USRP1 with WBX because I assume it
has better sensitivity than TVRX.

Why would you want to transmit anything if you’re just looking into
analyzing spectrum usage in TV channels?

LP0410 is covering the right frequency band for UHF (400 MHz to 1 GHz),
but it is a directional antenna. Is that what you want? Otherwise, you
might be better off using an omni antenna, preferably on a roof…

Here are a few pointers to papers on TV white spaces:

http://www.openspectrum.eu/drupal6/node/23

I’ve posted some of the key issues on this list two years ago:

White space sensing efforts - GNU Radio - Ruby-Forum

Dyspan has some nice papers on spectrum sensing as well:

http://www.ieee-dyspan.org/2010/

Now to the setup:

Hardware / sample data

I have a USRP1, two WBX, USRP1 N210 and an PC hardware available as
well, so unless you’re in a closed source / NDA environment, we could
set up a code repository on github, and I could provide you with sample
recordings from Hong Kong to cross-check detectors.

Regulatory environment / signals too look for

What is your location? From your signature, I assume you’re in the
Middle East, and I guess we’re talking mostly about DVB-T signals. Is
there still analog TV transmission around, wireless microphones, …?

gnuradio packages on Ubuntu

The gnuradio packages that come with Ubuntu 10.04 are most likely a bit
outdated, so you might want to upgrade your laptops to 11.10 first.

10.04 contains 3.0.4-2ubuntu1
(http://packages.ubuntu.com/hardy/gnuradio)
11.10 contains 3.2.2.dfsg-1ubuntu7
(http://packages.ubuntu.com/oneiric/gnuradio)

Once you’ve got 11.10 with the latest packages installed, you might want
to test your setup with some of the gnuradio examples, like a basic FM
receiver to tune in a local radio station.

Hope this helps for a start - please let us/me know on the mailing list
if you need more input :slight_smile:

Alex

[1] White spaces (radio) - Wikipedia

Hello Alex, I’ve been working on detecting White Spaces with USRP-E110
for a while now. I’m no expert, fought my way up from
uhd_spectrum_sense.py and managed to collect some coherent results
playing with bin_statistics.cpp.

Currently I’m “identifying” White Spaces based solely on the power of
the signal, but I’m aware of this technique’s weaknesses. Have you
implemented another method? (Stochastic analysis perhaps?)

Very appreciated in advance.

Luis.

Hello my frnd…
i too faced same kind of problem and was not getting any output from
usrp_spectrum_sense.py, only center frequencies were displayed on
terminal.
Then i added “print m.data” after line no 238 “Print m.center freq” and
saved it. Then to sense spectrum i gave command
$ sudo python usrp_spectrum_sense.py start_freq End_freq > capture.dat
and all your sensed data will get stored in this capture.dat file