[Discuss-gnuradio] Sometimes USRP sensitiviy goes down
Now I've tried communication test a lot of times. I send a signal like below: https://picasaweb.google.com/lh/photo/Ntw86qudmxB4Qu07Z1TNvQ?feat=directlink Then RX shows plot like below: https://picasaweb.google.com/lh/photo/H9RItzjpfemHy-OR2eQhQg?feat=directlink Most of time it's fine. However, very rarely, RX just shows white noise like below: https://picasaweb.google.com/lh/photo/jJdZIfm6Fd_mGNwu9QRBYQ?feat=directlink Every condition has not been changed I just turn USRP off and on and now I have this problem. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] wiener based SSB demodulator
Hello, i've build a wiener based SSB demodulator, and i was wondering, does the amplitude of the sine and cosine oscilators influence the general signals behaviour? Gr. Sim ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] try to install minimal gnu-radio
On Tue, Mar 15, 2011 at 12:59 AM, wrote:
> if i did
> GRC_GRUEL dnl must come first
> GRC_GCELL
> GRC_GNURADIO_CORE
> GRC_USRP
> GRC_USRP2
> dnl GRC_GR_USRP dnl this must come after GRC_USRP
> dnl GRC_GR_USRP2
> dnl GRC_GR_GCELLdnl this must come after GRC_GCELL
> and GRC_GNURADIO_CORE
> dnl GRC_GR_MSDD6000
> dnl GRC_GR_AUDIO_ALSA
> dnl GRC_GR_AUDIO_JACK
> dnl GRC_GR_AUDIO_OSS
> dnl GRC_GR_AUDIO_OSX
> dnl GRC_GR_AUDIO_PORTAUDIO
> dnl GRC_GR_AUDIO_WINDOWS
> dnl GRC_GR_ATSC
> dnl GRC_GR_COMEDI
> dnl GRC_GR_CVSD_VOCODER
> dnl GRC_GR_GPIO
> dnl GRC_GR_GSM_FR_VOCODER
> dnl GRC_GR_NOAA
> dnl GRC_GR_PAGER
> dnl GRC_GR_RADAR_MONO
> dnl GRC_GR_RADIO_ASTRONOMY
> dnl GRC_GR_TRELLIS
> dnl GRC_GR_VIDEO_SDL
> dnl GRC_GR_WXGUI
> dnl GRC_GR_QTGUI
> dnl GRC_GR_SOUNDER dnl this must come after GRC_USRP
> dnl GRC_GR_UTILS dnl this must come after GRC_GR_WXGUI
> GRC_GNURADIO_EXAMPLES dnl must come after all GRC_GR_*
> GRC_GRC
> GRC_DOCSdnl must be last
>
> this in configure
>
> then why it shows
>
> ./configure: line 6273: AC_LIBTOOL_WIN32_DLL: command not found
> ./configure: line 6274: AC_ENABLE_SHARED: command not found
> ./configure: line 6288: AC_PROG_LIBTOOL: command not found
> checking for python... /usr/bin/python
> checking for python version... 2.6
> checking for python platform... linux2
> checking for python script directory...
> ${prefix}/lib/python2.6/dist-packages
> checking for python extension module directory...
> ${exec_prefix}/lib/python2.6/dist-packages
> checking for Python include path... /usr/include/python2.6
> checking Python.h usability... no
> checking Python.h presence... no
> checking for Python.h... no
> configure: error: cannot find usable Python headers
>
> this error during configureaton (./configure)...
>
> is there any way to not install dependiencies packages (like python,
> swig)...
> if i do not want to install related things in gnuradio...
By default, GNU Radio core requires Python. Disable it by passing
"--disable-python" to the configure script.
Tom
> >
> >
> > On 03/14/2011 06:55 AM, shushank.sha...@zerosystems.in wrote:
> >> Hello every one i am start using gnu radio...
> >>
> >> i want to write configure.ac in a manner that only gnuradio-core in
> >> build...
> >>
> >> without giving any commandline option on configure script...
> >>
> >> How can i did this...
> >>
> >
> > comment out the GRC_GR_* lines in configure.ac
> >
> >> thanks
> >>
> >>
> >> ___
> >> Discuss-gnuradio mailing list
> >> Discuss-gnuradio@gnu.org
> >> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
> >
> > ___
> > Discuss-gnuradio mailing list
> > Discuss-gnuradio@gnu.org
> > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
> >
>
>
>
> ___
> Discuss-gnuradio mailing list
> Discuss-gnuradio@gnu.org
> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>
___
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] REF clock for USRP2
Would experienced users please recommend me a 10MHz REF clock for stabilizing USRP2? I followed previous emails and found that "any 10 MHz reference (square or sine wave, DC-blocked and terminated in 50 ohms, 3V pk-pk) with will suffice, it does not need to be a pulse per second source." As such, is there any existing product that I can purchase directly. A REF clock without GPSDO will be excellent. Than you in advance, Andrew ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] REF clock for USRP2
On 03/15/2011 11:54 AM, Feng Andrew Ge wrote: > > Would experienced users please recommend me a 10MHz REF clock for > stabilizing USRP2? I followed previous emails and found that "any 10 > MHz reference (square or sine wave, DC-blocked and terminated in 50 > ohms, 3V pk-pk) with will suffice, it does not need to be a pulse per > second source." As such, is there any existing product that I can > purchase directly. > A REF clock without GPSDO will be excellent. > > Than you in advance, > Andrew > > > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio > Something like this: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=535-10099-ND Should work just fine, although you'll have to take care of providing power and connections yourself. -- Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] tunnel.py printing string of "B"s
I'm trying to run tunnel.py on my Atom PC with a USRP 1 hooked up. I'm attemping to run it with a Fc of 4 Mhz and the standard values (Basic RX and LF Tx daughterboards). The terminal window is filling up with the "B character and I can't determine a) why that's happening and b) where it's coming from. Thoughts? Thanks. -William ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] tunnel.py printing string of "B"s
On Tue, Mar 15, 2011 at 3:03 PM, William Cox wrote: > I'm trying to run tunnel.py on my Atom PC with a USRP 1 hooked up. I'm > attemping to run it with a Fc of 4 Mhz and the standard values (Basic RX and > LF Tx daughterboards). > The terminal window is filling up with the "B character and I can't > determine a) why that's happening and b) where it's coming from. > Thoughts? > Thanks. > -William > The "B" is part of our "CSMA" MAC layer telling you that it's blocked from transmitting due to high received signal strength in the channel. You can play with the threshold level for the detection with the -c option. Tom ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Computing Power Spectra
Hello,
I wrote a simple grc graph to compute power spectra of the output of the
usrp. My test setup is a signal generator outputting a tone at the same
frequency that I set as the usrp center frequency, directly connected to
the usrp. But when I examine the output in Matlab, the first vector is
exactly what I expect, a peak at the center and then the noise floor.
The following vectors show the peak at lower and lower power levels
until, after 10 or so, it disappears into the noise. My code is
attached. Anybody know what could be causing this?
Any help would be appreciated.
Scott
--
Scott Johnston
MIT Lincoln Laboratory
244 Wood Street, Lexington, MA 02420-9108
(781) 981-8196
scott.johns...@ll.mit.edu
#!/usr/bin/env python
##
# Gnuradio Python Flow Graph
# Title: Logpowertest
# Generated: Tue Mar 15 17:36:43 2011
##
from gnuradio import blks2
from gnuradio import eng_notation
from gnuradio import gr
from gnuradio import uhd
from gnuradio import window
from gnuradio.eng_option import eng_option
from gnuradio.gr import firdes
from optparse import OptionParser
class logpowertest(gr.top_block):
def __init__(self):
gr.top_block.__init__(self, "Logpowertest")
##
# Variables
##
self.samp_rate = samp_rate = 32000
##
# Blocks
##
self.blks2_stream_to_vector_decimator_0 = blks2.stream_to_vector_decimator(
item_size=gr.sizeof_gr_complex,
sample_rate=samp_rate,
vec_rate=30,
vec_len=1024,
)
self.gr_complex_to_mag_squared_0 = gr.complex_to_mag_squared(1024)
self.gr_fft_vxx_0 = gr.fft_vcc(1024, True, (window.blackmanharris(1024)), True)
self.gr_file_sink_0 = gr.file_sink(gr.sizeof_float*1024, "/home/user/Desktop/logpowertest.bin")
self.gr_file_sink_0.set_unbuffered(False)
self.gr_nlog10_ff_0 = gr.nlog10_ff(10, 1024, 0)
self.uhd_single_usrp_source_0 = uhd.single_usrp_source(
device_addr="addr=192.168.10.2",
io_type=uhd.io_type.COMPLEX_FLOAT32,
num_channels=1,
)
self.uhd_single_usrp_source_0.set_clock_config(uhd.clock_config.external());
self.uhd_single_usrp_source_0.set_samp_rate(.2e6)
self.uhd_single_usrp_source_0.set_center_freq(800e6, 0)
self.uhd_single_usrp_source_0.set_gain(0, 0)
##
# Connections
##
self.connect((self.gr_fft_vxx_0, 0), (self.gr_complex_to_mag_squared_0, 0))
self.connect((self.gr_complex_to_mag_squared_0, 0), (self.gr_nlog10_ff_0, 0))
self.connect((self.uhd_single_usrp_source_0, 0), (self.blks2_stream_to_vector_decimator_0, 0))
self.connect((self.blks2_stream_to_vector_decimator_0, 0), (self.gr_fft_vxx_0, 0))
self.connect((self.gr_nlog10_ff_0, 0), (self.gr_file_sink_0, 0))
def set_samp_rate(self, samp_rate):
self.samp_rate = samp_rate
self.blks2_stream_to_vector_decimator_0.set_sample_rate(self.samp_rate)
if __name__ == '__main__':
parser = OptionParser(option_class=eng_option, usage="%prog: [options]")
(options, args) = parser.parse_args()
if gr.enable_realtime_scheduling() != gr.RT_OK:
print "Error: failed to enable realtime scheduling."
tb = logpowertest()
tb.start()
raw_input('Press Enter to quit: ')
tb.stop()
Tue Mar 15 17:36:42 2011
variable
id
samp_rate
_enabled
True
value
32000
_coordinate
(10, 170)
_rotation
0
gr_complex_to_mag_squared
id
gr_complex_to_mag_squared_0
_enabled
True
vlen
1024
_coordinate
(910, 187)
_rotation
0
uhd_single_usrp_source
id
uhd_single_usrp_source_0
_enabled
True
type
complex
nchan
1
dev_addr
addr=192.168.10.2
ref_clk
ext
sd_spec
samp_rate
.2e6
center_freq0
800e6
gain0
0
ant0
bw0
0
center_freq1
0
gain1
0
ant1
bw1
0
center_freq2
0
gain2
0
ant2
bw2
0
center_freq3
0
gain3
0
ant3
bw3
0
_coordinate
(182, 75)
_rotation
0
gr_fft_vxx
id
gr_fft_vxx_0
_enabled
True
type
complex
fft_size
Re: [Discuss-gnuradio] Computing Power Spectra
On Tue, 2011-03-15 at 17:48 -0400, Scott Johnston wrote:
> Hello,
>
> I wrote a simple grc graph to compute power spectra of the output of the
> usrp. My test setup is a signal generator outputting a tone at the same
> frequency that I set as the usrp center frequency, directly connected to
> the usrp. But when I examine the output in Matlab, the first vector is
> exactly what I expect, a peak at the center and then the noise floor.
> The following vectors show the peak at lower and lower power levels
> until, after 10 or so, it disappears into the noise. My code is
> attached. Anybody know what could be causing this?
My guess is DC offset correction. Receiving an unmodulated baseband
signal will just look like DC, which will get offset corrected in the
FPGA. Try generating a signal very slightly offset from the USRP receive
freq.
--n
>
> Any help would be appreciated.
>
> Scott
>
> Python script attachment (logpowertest.py)
> #!/usr/bin/env python
> ##
> # Gnuradio Python Flow Graph
> # Title: Logpowertest
> # Generated: Tue Mar 15 17:36:43 2011
> ##
>
> from gnuradio import blks2
> from gnuradio import eng_notation
> from gnuradio import gr
> from gnuradio import uhd
> from gnuradio import window
> from gnuradio.eng_option import eng_option
> from gnuradio.gr import firdes
> from optparse import OptionParser
>
> class logpowertest(gr.top_block):
>
> def __init__(self):
> gr.top_block.__init__(self, "Logpowertest")
>
> ##
> # Variables
> ##
> self.samp_rate = samp_rate = 32000
>
> ##
> # Blocks
> ##
> self.blks2_stream_to_vector_decimator_0 =
> blks2.stream_to_vector_decimator(
> item_size=gr.sizeof_gr_complex,
> sample_rate=samp_rate,
> vec_rate=30,
> vec_len=1024,
> )
> self.gr_complex_to_mag_squared_0 =
> gr.complex_to_mag_squared(1024)
> self.gr_fft_vxx_0 = gr.fft_vcc(1024, True,
> (window.blackmanharris(1024)), True)
> self.gr_file_sink_0 = gr.file_sink(gr.sizeof_float*1024,
> "/home/user/Desktop/logpowertest.bin")
> self.gr_file_sink_0.set_unbuffered(False)
> self.gr_nlog10_ff_0 = gr.nlog10_ff(10, 1024, 0)
> self.uhd_single_usrp_source_0 = uhd.single_usrp_source(
> device_addr="addr=192.168.10.2",
> io_type=uhd.io_type.COMPLEX_FLOAT32,
> num_channels=1,
> )
>
> self.uhd_single_usrp_source_0.set_clock_config(uhd.clock_config.external());
> self.uhd_single_usrp_source_0.set_samp_rate(.2e6)
> self.uhd_single_usrp_source_0.set_center_freq(800e6, 0)
> self.uhd_single_usrp_source_0.set_gain(0, 0)
>
> ##
> # Connections
> ##
> self.connect((self.gr_fft_vxx_0, 0),
> (self.gr_complex_to_mag_squared_0, 0))
> self.connect((self.gr_complex_to_mag_squared_0, 0),
> (self.gr_nlog10_ff_0, 0))
> self.connect((self.uhd_single_usrp_source_0, 0),
> (self.blks2_stream_to_vector_decimator_0, 0))
> self.connect((self.blks2_stream_to_vector_decimator_0, 0),
> (self.gr_fft_vxx_0, 0))
> self.connect((self.gr_nlog10_ff_0, 0), (self.gr_file_sink_0, 0))
>
> def set_samp_rate(self, samp_rate):
> self.samp_rate = samp_rate
>
> self.blks2_stream_to_vector_decimator_0.set_sample_rate(self.samp_rate)
>
> if __name__ == '__main__':
> parser = OptionParser(option_class=eng_option, usage="%prog: [options]")
> (options, args) = parser.parse_args()
> if gr.enable_realtime_scheduling() != gr.RT_OK:
> print "Error: failed to enable realtime scheduling."
> tb = logpowertest()
> tb.start()
> raw_input('Press Enter to quit: ')
> tb.stop()
>
> XML document attachment (logpowerTest.grc)
>
>
> Tue Mar 15 17:36:42 2011
>
> variable
>
> id
> samp_rate
>
>
> _enabled
> True
>
>
> value
> 32000
>
>
> _coordinate
> (10, 170)
>
>
> _rotation
> 0
>
>
>
> gr_complex_to_mag_squared
>
> id
> gr_complex_to_mag_squared_0
>
>
> _enabled
> True
>
>
> vlen
> 1024
>
>
> _coordinate
> (910, 187)
>
[Discuss-gnuradio] lowest power of the signal that LFRX can receive
Dear all, What is the lowest power of the signal that LFRX can receive? Really appreciate any of your help Yan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Computing Power Spectra
On Tue, Mar 15, 2011 at 4:48 PM, Scott Johnston wrote: > Hello, > > I wrote a simple grc graph to compute power spectra of the output of the > usrp. My test setup is a signal generator outputting a tone at the same > frequency that I set as the usrp center frequency, directly connected to the > usrp. But when I examine the output in Matlab, the first vector is exactly > what I expect, a peak at the center and then the noise floor. The following > vectors show the peak at lower and lower power levels until, after 10 or so, > it disappears into the noise. My code is attached. Anybody know what could > be causing this? My guess is that you are seeing a DC offset correction loop closing. This would occur if the RF tone of interest is downconverted to DC (which sounds like what you described). I don't recall how DC offset correction is actually implemented in USRP land, but it may very well take a few tens/hundreds of samples before it is completely corrected, which lines up with what you're seeing. Try changing your sig gen to output a tone at, say 100 Khz from your RF tuning frequency, and it should not attenuate over time. -- John Orlando CEO/System Architect Epiq Solutions http://www.epiq-solutions.com ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] lowest power of the signal that LFRX can receive
Dear all, What is the lowest power of the signal that LFRX can receive? Really appreciate any of your help Yan The LFRX has almost no gain, so you're limited by the noise floor of the ADC. In the USRP2, you can probably reliably detect signals down to about -60dBm or so. In the USRP1, you need somewhat more signal, about -50dBm or so. But those are ballpark numbers. But it depends on the details, and what kind of signals you're trying to detect, and whether you want to demodulate them, or merely detect their presence, etc. -- Marcus Leech Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] lowest power of the signal that LFRX can receive
On Wed, Mar 16, 2011 at 1:07 AM, Marcus D. Leech wrote: >> Dear all, >> >> What is the lowest power of the signal that LFRX can receive? >> >> Really appreciate any of your help >> >> Yan >> > The LFRX has almost no gain, so you're limited by the noise floor of the > ADC. In the USRP2, you can probably reliably detect > signals down to about -60dBm or so. In the USRP1, you need somewhat more > signal, about -50dBm or so. But those are > ballpark numbers. But it depends on the details, and what kind of signals > you're trying to detect, and whether you want to > demodulate them, or merely detect their presence, etc. Using a signal generator I could measure the "CW sensitivity" down to about -90 dBm. Using a 2 kHz filter this produced a tone clear enough for me to decode morse code. With a tuned vertical antenna ~10 meters long, I get very good reception of AM broadcasting and ham radio traffic around 7 MHz. I was using USRP1. Alex ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Can static cause USRP work inproperly?
At least, until the day before yesterday, my flow graph works fine with USRP TX: https://picasaweb.google.com/lh/photo/FVqGp6Qt39P3nP-DLzm2pg?feat=directlink RX: https://picasaweb.google.com/lh/photo/rKCvVTq9Ptst_u2Z0TvCDw?feat=directlink Suddenly, however, yesterday received signal strength is much lower than normal TX: https://picasaweb.google.com/lh/photo/Ntw86qudmxB4Qu07Z1TNvQ?feat=directlink RX (normal): https://picasaweb.google.com/lh/photo/H9RItzjpfemHy-OR2eQhQg?feat=directlink RX (abnormal): https://picasaweb.google.com/lh/photo/jJdZIfm6Fd_mGNwu9QRBYQ?feat=directlink It looks like just a noise, but it's a kind of rectangular pulse. (Just, signal strength is similar to noise) RX in normal shows count with about 1k but RX in abnormal? count with just tens How could it happen? I changed nothing but just turning on and off the USRP ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] lowest power of the signal that LFRX can receive
On 03/15/11, Alexandru Csete wrote: > > On Wed, Mar 16, 2011 at 1:07 AM, Marcus D. Leech wrote: > >> Dear all, > >> > >> What is the lowest power of the signal that LFRX can receive? > >> > >> Really appreciate any of your help > >> > >> Yan > >> > > The LFRX has almost no gain, so you're limited by the noise floor of the > > ADC. In the USRP2, you can probably reliably detect > > signals down to about -60dBm or so. In the USRP1, you need somewhat more > > signal, about -50dBm or so. But those are > > ballpark numbers. But it depends on the details, and what kind of signals > > you're trying to detect, and whether you want to > > demodulate them, or merely detect their presence, etc. > > Using a signal generator I could measure the "CW sensitivity" down to > about -90 dBm. Using a 2 kHz filter this produced a tone clear enough > for me to decode morse code. With a tuned vertical antenna ~10 meters > long, I get very good reception of AM broadcasting and ham radio > traffic around 7 MHz. I was using USRP1. > > Alex Really appreciate your reply. The signal that is trying to be detected is -117dBm, which turns out a larger amplifier is need in my case. I have another question really need your help: how to corresponds the amplitude set by program to the Vp-p of the front end output of LFTX? Also the same question with receiver side, how to corresponds the amplitude to the received signal Vp-p. The amplitude at transmitter side is set by the program and at receiver side the amplitude is the one of the signal after DDC. Really appreciate your help Yan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
