Re: [Discuss-gnuradio] How to finish the rx_callback? in benchmark_ofdm_rx.py
I'm not very clear with your method3. But what we use is very similar
with this method. When we want to jump out from the callback's block
status, we send a useless pkt to it to make it quit out.
Lin
2010/4/20 Sung Jeen Jang wireless.j...@gmail.com:
Hello all
At first, I appreciate you read my text.
My problem is that
how to finish the rx_callback in benchmark_ofdm_rx.py
I think that the structure of benchmark_ofdm_rx.py is like this.
make rx_callback and return this to my_top_block
and return my_top_block to tb
and tb.start()
I want to receive the data in 2.5e9 Hz one time.
and second time receive the data in 2.6e9 Hz.
So I would like to make this scenario.
Receiving the data in specific frequency
and receiving the data in another frequency.
I tried these method, but failed.
failed method 1:
tb = my_top_block(rx_callback, options)
tb.start()
tb.wait() #-- process goes into here and cannot escape
tb.stop()
failed method 2:
tb = my_top_block(rx_callback, options)
tb.start()
tb.stop() # - process broken here
tb.wait()
method 3:
def rx_callback(ok, payload):
n=0
while n1000:
n += 1
(pktno,) = struct.unpack('!H', payload[0:2])
# -- after n goes over 1000, process broken
So, is there good method to this problem?
In combining sensing transmit, I succeed like this
if __name__ == '__main__':
tb_wsensing = my_top_block()
while 1:
tb_wsensing.start() # start executing flow graph in
another
thread...
main_loop(tb_wsensing)
tb_wsensing.stop()
tb_wsensing.wait()
whichfreq=open(minfreq.dat)
a=whichfreq.readline()
freq_offset=float(a)
print a
transmit()
Thank you very very very much for your reading.
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[Discuss-gnuradio] Importing Filter Taps
I need to import complex filter taps from a .txt file and use them in FFT FIlter block in GRC. How can I do that? Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Problem with multiple flow graphs on receive side
OK, abbasi wrote: Hi Sriram , Did you managed to solve your problem? I'm doing the same, but i don't have any errors. The connecting process is ok, but i think there is a conflict between the call_back of the receiving path and the eval function of the sensing path? have you faced some problem like this? if yes, please inform how did you solve it. regards, Sriram Krishnan-3 wrote: Hi, I am trying to write an application which senses spectrum (usrp_spectrum_sense.py) and transmits/receives signals. I have the tx/rx working fine. But when i add another flow graph(3rd one to existing tx and rx) for the spectrum sense,to the top block, it gives me an error. I get an error on this line which says cant open rx interface and device busy self._u = usrp.source_c (self._which, fusb_block_size=self._fusb_block_size, fusb_nblocks=self._fusb_nblocks) Is it because of competing receive paths. I thought that we could have multiple paths. Could somebody help in this regard. Sriram ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio -- View this message in context: http://old.nabble.com/Problem-with-multiple-flow-graphs-on-receive-side-tp24526593p28287998.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] two call back function from C
dump, It was another problem abbasi wrote: Hi, Is it not possible to have two call back functions from C++ part to python. for example: 1. The call back eval from the gr.bin_statistics_f block 'sink' and 2. The call back from the receive path in tunnel.py class phy_rx_callback I think they are both contradicting each other. so if one works the other cannot work (the first one to be called usually works) Does this mean that we cannot have parallel flow graphs running at the same time and calling from C++ to python? regards, -- View this message in context: http://old.nabble.com/two-call-back-function-from-C-tp28287675p28287999.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Importing Filter Taps
My walkthrough:
1) matlab, e.g. A=[3+4i 4+3i 5+2.3i 6 3.4i]
2) copy A to clipboard: clipboard('copy', A)
3) with xclip and sed, the clipboard's content is converted to
something python understands: xclip -o -selection c | sed -r -e
's/^\[//' -e 's/\]$//' -e 's/ /,/g' -e 's/i\*([^,]*),/\1j,/g' -e
's/i\*(.*)$/\1j/' taps_c.txt
4) from numpy import *
5) e.g. self.filter = gr.interp_fir_filter_ccc(1,
genfromtxt(taps_c.txt, dtype=complex, delimiter=,))
Cheers,
Gregor
2010/4/21 Umair Naeem ar...@student.chalmers.se:
I need to import complex filter taps from a .txt file and use them in FFT
FIlter block in GRC. How can I do that?
Regards,
Umair Naeem
MSc Communication Engineering
Chalmers University ot Technology, Sweden.
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[Discuss-gnuradio] fix for usrp2 overruns when stopping and restarting rx streaming
Hi All,
When you use an USRP2 for capturing and you call
u2-stop_rx_streaming()
and later
u2-start_rx_streaming(0)
You always get a single overrun.
-a single 'S' is output on the console
-u2-rx_overruns() returns 1 (in stead of 0)
I am developing a usrp2 application which does not permit any overrun
conditions, so this needed fixing.
It turns out that the expected sequence number of received samples is
not reset when stopping the stream.
This single line patch fixes this.
Best Regards,
Martin
diff --git a/usrp2/host/lib/usrp2_impl.cc b/usrp2/host/lib/usrp2_impl.cc
index b19c6ec..92d52db 100644
--- a/usrp2/host/lib/usrp2_impl.cc
+++ b/usrp2/host/lib/usrp2_impl.cc
@@ -814,6 +814,7 @@ namespace usrp2 {
success = transmit_cmd_and_wait(cmd, sizeof(cmd), p,
DEF_CMD_TIMEOUT);
success = success (ntohx(reply.ok) == 1);
d_channel_rings[channel].reset();
+ d_rx_seqno=-1;
//fprintf(stderr, usrp2::stop_rx_streaming: success = %d\n,
success);
return success;
}
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[Discuss-gnuradio] CIC filter block
Hello Just checking before: does anybody have a CIC filter implementation for GR? Thanks in advance. Alberto Presentaci un amico! Invita i tuoi amici a scoprire i servizi Tiscali: per ogni amico che attiverà un servizio Tiscali, potrai avere 30 euro di sconto e lo stesso sconto di 30 euro verrà poi offerto al tuo amico. Scopri come! http://abbonati.tiscali.it/presentaci_un_amico/?WT.mc_id=01fw ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] DQPSK Modulation/Demodulation issue
I've recently been working on transmitting data from a vector source via DQPSK. I've created a Simulation [non USRP] with the following flow graph: TX Vector Source [0x6c] ie 01 10 11 00 Packed To Unpacked Mapper [Binary 2 Gray] Differential Encoder Chunks to Symbols RX Differential Phasor Constellation Decoder Mapper [Gray 2 Binary] Unpacked To Packed Vector Sink For differential encoding, i've also ammended the first input byte to be 0. The Output for the simulation is as expected: ie. Input = 0 108 108 108 108 108 108 ... Output = 0 108 108 108 108 108 108 ... When i try transmitting this data through the USRP however, i receive 4 possible outputs. These include: 108 [which is correct] 177 [wrong] 108 [wrong] 27 [wrong] These are funnily the 4 possible outputs which have all possible symbols in 1 byte. ie 00 01 10 11 The output varies, one time i might get all 108s as expected , and other times ill get one of the other 3 outputs. The signal constellation at the output of the differential phasor looks correct. Does anyone have any idea what is going wrong here? I've included my python source code below: ## # Gnuradio Python Flow Graph # Title: Qpsktest # Generated: Thu Apr 22 02:01:45 2010 ## from gnuradio import gr from gnuradio.blks2impl import psk from gnuradio.eng_option import eng_option from gnuradio.gr import firdes from grc_gnuradio import usrp as grc_usrp from grc_gnuradio import wxgui as grc_wxgui from optparse import OptionParser import wx class QPSKtest(gr.top_block): def __init__(self): gr.top_block.__init__(self) ## # Variables ## self.arity = arity = pow(2,2) self.samp_rate = samp_rate = 256000 self.rotated_const = rotated_const = map(lambda pt: pt * 1, psk.constellation[arity]) self.rot = rot = .707 + .707j self.data = 10 * [0x6C,] ## Initial Block to Capture data from Vector Source and then Add 0 at the beginning fg = gr.top_block() self.vectorSource = gr.vector_source_b(self.data, False, 1) self.VSINK = gr.vector_sink_b(1) fg.connect(self.vectorSource, self.VSINK) fg.run() actual_data = self.VSINK.data() ##make first data element 0 for the sake of the Diff Encoder etc actual_data_copy = (0,) + actual_data[1:] print actual_data_copy ## # Main Blocks ## self.gr_chunks_to_symbols_xx_0 = gr.chunks_to_symbols_bc((map(lambda pt: pt * rot, psk.constellation[arity])), 1) self.gr_clock_recovery_mm_xx_0 = gr.clock_recovery_mm_cc(2, 0.25 * 0.03 * 0.03, 0.05, 0.03, 0.005) self.gr_constellation_decoder_cb_0 = gr.constellation_decoder_cb((rotated_const), (range(arity))) self.gr_costas_loop_cc_0 = gr.costas_loop_cc(0.10, 0.25 * 0.1 * 0.1, 0.002, -0.002, 4) self.gr_diff_encoder_bb_0 = gr.diff_encoder_bb(arity) self.gr_diff_phasor_cc_0 = gr.diff_phasor_cc() self.gr_feedforward_agc_cc_0 = gr.feedforward_agc_cc(16, 1.0) self.gr_fir_filter_xxx_1 = gr.fir_filter_ccf(1, (gr.firdes.root_raised_cosine(2,2,1.0,0.35,22))) self.gr_interp_fir_filter_xxx_0 = gr.interp_fir_filter_ccf(2, (gr.firdes.root_raised_cosine(2, 2, 1.0, 0.35, 22))) self.gr_map_bb_0 = gr.map_bb((psk.binary_to_gray[arity])) self.gr_map_bb_0_0 = gr.map_bb((psk.gray_to_binary[arity])) self.gr_multiply_const_vxx_0 = gr.multiply_const_vcc(((1.0/16384.0), )) self.gr_multiply_const_vxx_0_1 = gr.multiply_const_vcc((16384.0, )) self.gr_packed_to_unpacked_xx_0 = gr.packed_to_unpacked_bb(2, gr.GR_MSB_FIRST) self.gr_unpacked_to_packed_xx_0 = gr.unpacked_to_packed_bb(2, gr.GR_MSB_FIRST) self.dataSource = gr.vector_source_b(actual_data_copy, False, 1) self.usrp_simple_sink_x = grc_usrp.simple_sink_c(which=0, side=B) self.usrp_simple_sink_x.set_interp_rate(500) self.usrp_simple_sink_x.set_frequency(243000, verbose=True) self.usrp_simple_sink_x.set_gain(0) self.usrp_simple_sink_x.set_enable(True) self.usrp_simple_source_x_0_0 = grc_usrp.simple_source_c(which=0, side=B, rx_ant=RX2)
[Discuss-gnuradio] Sending extra info (rssi) in ethernet frames from USRP2 to host
Hi, * I am reading through the firmware C codes and trying to figure out how to carry the RSSI values from auxiliary ADC in the word0 section of each ethernet frame. I was confused by the structure of the firmware C codes. In the main() of txrx.c, there is no explicit function calls looks like send(), recv() for handing the ethernet frames. And I found in mimo_app_common_v2.c some functions like send_reply(), set_reply_hdr() and handle_control_chan_frame() which may correspond to this issue. I also tried to modify the u2p_set_word0() function in usrp2_eth_packet.h in order to carry the RSSI value. But it seems that this only works when starting streaming as every frame rceived on the host side shows the same value. I really want to know how does the frameware handle the samples and controlling frames. Any hints? Thanks in advance. Hanwen ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: fix for usrp2 overruns when stopping and restarting rx streaming
On Wed, Apr 21, 2010 at 04:08, Martin DvH gnuradiom...@olifantasia.com wrote: This single line patch fixes this. This has been applied on the master branch. Johnathan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Importing Filter Taps
you can call numpy.fromfile in grc http://docs.scipy.org/doc/numpy/reference/generated/numpy.fromfile.html if it cant find the numpy module, add an import block that has import numpy -Josh On 04/21/2010 02:09 AM, Umair Naeem wrote: I need to import complex filter taps from a .txt file and use them in FFT FIlter block in GRC. How can I do that? Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. ___ 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] Re: Sending extra info (rssi) in ethernet frames from USRP2 to host
Forget to mention, we are using GR 3.2.2, not the newer one with UDP supported. Cheers, Hanwen 2010/4/21 hanwen kidult.han...@gmail.com Hi, * I am reading through the firmware C codes and trying to figure out how to carry the RSSI values from auxiliary ADC in the word0 section of each ethernet frame. I was confused by the structure of the firmware C codes. In the main() of txrx.c, there is no explicit function calls looks like send(), recv() for handing the ethernet frames. And I found in mimo_app_common_v2.c some functions like send_reply(), set_reply_hdr() and handle_control_chan_frame() which may correspond to this issue. I also tried to modify the u2p_set_word0() function in usrp2_eth_packet.h in order to carry the RSSI value. But it seems that this only works when starting streaming as every frame rceived on the host side shows the same value. I really want to know how does the frameware handle the samples and controlling frames. Any hints? Thanks in advance. Hanwen ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP2 FPGA documentation
Hi, Is there any documentation or source code available for signal processing done in the USRP2 FPGA? I have seen lots of block diagrams, etc. for USRP but been unable to find anythign similar for usrp 1. Thanks, Dave ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP2 FPGA documentation
On Wed, Apr 21, 2010 at 11:42 AM, David Barton david.barto...@yahoo.com wrote: Hi, Is there any documentation or source code available for signal processing done in the USRP2 FPGA? I have seen lots of block diagrams, etc. for USRP but been unable to find anythign similar for usrp 1. Source code is found on Matt's redmine: http://code.ettus.com/redmine/ettus/projects/fpga/repository Documentation seems sparse if non-existent. I am sure he would welcome anyone who would want to provide said documentation. Thanks, Dave Hope this helps! Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] DPSK Modulator and Demodulator
Hi, I am having trouble the the DBPSK mod and demod blocks. My flow graph is: file source - DBPSKmod - DBPSKdemod - file sink The file source is a 2 byte text file set to not repeat The default parameters were used for the DBPSKmod and demod blocks (including 2 Samples/Symbol) When I run the graph the output text file becomes 13 bytes long and they are almost all zeros. I am not sure how it gets to be that length. I tried connecting the ouput of the DBPSKmod directly to the file sink and the file size was 256 bytes. This matched my expectations based on: 2bytes input file * 8bits/byte * 1Symbol/bit * 2 complex samples/Symbol* 8bytes /complex sample = 256 byte output file. If anyone knows why the output file of the whole graph would be 13 bytes or if I am missing something please let me know. Thanks, Dave ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Regarding...modulation used by usrp...
Hello, I am using USRP with FLEX900 daughter board, i want to ask you that while transmission what kind of *modulation technique*, used by USRP for transmitting data. Thanks Ali ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Regarding...modulation used by usrp...
On Wed, Apr 21, 2010 at 2:34 PM, Muhammad Ali Khan mak...@gmail.com wrote: Hello, I am using USRP with FLEX900 daughter board, i want to ask you that while transmission what kind of modulation technique, used by USRP for transmitting data. Which modulation technique would be an acceptable answer? Thanks Ali Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP2 FPGA register control
Dear all, I searched the email achieve and Internet, only usrp FPGA control information can be found. http://gnuradio.org/redmine/wiki/1/UsrpFAQFpgaRegs u = usrp.source_c() u._write_fpga_reg(regno, val) set_register(FR_ADC_OFFSET_0, 0); Nothing related to usrp2 was reported. If I want to write to USRP2 FPGA register, is there any similar function I can call? Can I write to user-defined registers which I manually add into the verilog .v file? Thanks and have a good day! Regards, xj _ The New Busy is not the too busy. Combine all your e-mail accounts with Hotmail. http://www.windowslive.com/campaign/thenewbusy?tile=multiaccountocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] importing usrp2 module failing
Hi all, I installed GNU Radio via the Ubuntu package first, and when trying to run usrp2_probe, i got the error ImportError: cannot import name usrp2 ... so then I tried a manual install from the latest git, and I still get that same error. I have confirmed that gnuradio exists in: /usr/local/lib/python2.6/dist-packages/gnuradio I see the usrp2 module here: -rw-r--r-- 1 root staff 58800 2010-04-21 14:34 /usr/local/lib/python2.6/dist-packages/gnuradio/usrp2.py /usr/local/lib/python2.6/dist-packages is in the sys.path variable in python: sys.path ['', '/usr/lib/python2.6', '/usr/lib/python2.6/plat-linux2', '/usr/lib/python2.6/lib-tk', '/usr/lib/python2.6/lib-old', '/usr/lib/python2.6/lib-dynload', '/usr/lib/python2.6/dist-packages', '/usr/lib/python2.6/dist-packages/Numeric', '/usr/lib/python2.6/dist-packages/PIL', '/usr/lib/python2.6/dist-packages/gst-0.10', '/usr/lib/pymodules/python2.6', '/usr/lib/python2.6/dist-packages/gtk-2.0', '/usr/lib/pymodules/python2.6/gtk-2.0', '/usr/lib/python2.6/dist-packages/wx-2.6-gtk2-unicode', '/usr/lib/python2.6/dist-packages/wx-2.8-gtk2-unicode', '/usr/local/lib/python2.6/dist-packages'] **NOTE** I do not get the import error when I do not run the command with sudo, but then I do not get the proper raw socket permissions. Maybe that rings a bell to someone? Something probably about an environment variable I am missing. Thanks! George ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: importing usrp2 module failing
**NOTE** I do not get the import error when I do not run the command with sudo, but then I do not get the proper raw socket permissions. Maybe that rings a bell to someone? Something probably about an environment variable I am missing. actually... I am getting the same error now without using sudo, so that doesn't seem to be a difference - George ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ATSC decoding
Tom Rondeau trondeau1...@gmail.com 04/20/10 9:58 AM On Mon, Apr 19, 2010 at 8:12 PM, Stephen Branch bran...@auburn.edu wrote: Hello everyone, I am part of Auburn University's Software Defined Radio Senior Design team, Software being used: Ubuntu v.9.10 on xfs partition GNURadio v.3.3 (git) Xine Available hardware: USRP1, USRP2, WBX daughterboard, TVRX daughterboard We followed the instructions in ./gnuradio/gr-atsc/src/python/README to no success. Using the FFT we found 507.25M to have a strong signal. According to http://en.wikipedia.org/wiki/North_American_broadcast_television_frequencies#UHF_band this is channel 20. And according to http://www.fcc.gov/fcc-bin/tvq?state=ALcall=arn=city=chan=14cha2=69serv=type=0facid=list=2dist=dlat2=mlat2=slat2=dlon2=mlon2=slon2=size=9 this is WCOV from Montgomery, Alabama. So we do have the correct video carrier frequency, which I assume is the frequency we want to record and decode into a video. Question #1) Is the video carrier the one that carriers the video, or would it be the ATSC carrier? If it's ATSC, you should see a very strong carrier with a very small lump of energy to the left of it (this is the vestigial sideband) and a large, fairly flat signal to the right that rolls off. This likely won't be flat due to fading, but you should be able to recognize it as a 6 MHz chunk of spectrum being occupied. You probably already know this, but I'm pointing it out to help distinguish between the ATSC carrier and video carrier. In NTSC, there were a few different carriers while in ATSC there's just the one big guy. And you want to use the ATSC carrier. This wikipedia article gives you the frequencies: http://en.wikipedia.org/wiki/Television_channel_frequencies#Americas_.28most_countries.29.2C_South_Korea.2C_Taiwan_and_the_Philippines For the channel you're looking at (20), the carrier would be at 507.31 MHz. There's a PLL to lock to the carrier, but I'm not sure if it's broad enough to handle the 60 kHz offset you're using. This could be the cause of your problem. In general, you should be able to output the different stages to files by editing the Python code and take a look at different stages to see what's going on. This might help identify where the problem is. Tom We then used: ./usrp_rx_cfile.py -s -d 10 -g 20 -f 507.25e6 atsc_data_6-4m_complex ./interp_short.py atsc_data_6-4m_complex ./xlate.py ./fpll.py ./btl-fsd.py ./viterbi-out.py test.mpeg Problems: /tmp/atsc_pipe_5 never fills with data. The output file, 'test.mpeg' is empty. Question #2) What do we need to fix to get /tmp/atsc_pipe_5 to fill. Question #3) What do we need to fix to get temp.mpeg to fill. Thank you, Bobby Black Stephen Branch Auburn University blac...@auburn.edu (334) 804-4826 Thanks Tom, Just for clarification: You said: For the channel you're looking at (20), the carrier would be at 507.31 MHz. There's a PLL to lock to the carrier, but I'm not sure if it's broad enough to handle the 60 kHz offset you're using. This could be the cause of your problem. What exactly do you mean by a 60kHz offset? We're not sure where we are using such an offset. Are there alternatives to how we're doing this that may yield better results? Thanks again, Auburn University Senior Design Team: Software Group Stephen Branch and Bobby Black bran...@auburn.edu blac...@auburn.edu ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] ATSC decoding
On Wed, Apr 21, 2010 at 3:48 PM, Stephen Branch bran...@auburn.edu wrote: Hi Tom, Thanks for the response. Just for clarification: You said: For the channel you're looking at (20), the carrier would be at 507.31 MHz. There's a PLL to lock to the carrier, but I'm not sure if it's broad enough to handle the 60 kHz offset you're using. This could be the cause of your problem. What exactly do you mean by a 60kHz offset? We're not sure where we are using such an offset. Are there alternatives to how we're doing this that may yield better results? You said you were looking for a carrier at 507.25 MHz. I said the carrier is at 507.31 MHz. That's a 60 kHz offset. Tom ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: importing usrp2 module failing
thanks Josh! I seem to have had a conflicting install in /usr/lib/ rather than /usr/local/lib, so i blasted it and updated PYTHONPATH and all is great again ;) - George On Wed, Apr 21, 2010 at 4:14 PM, Josh Blum j...@joshknows.com wrote: its probably an issue of PYTHONPATH, make sure that the import works on command line: python -c from gnuradio import usrp2 You should not need to run as root as long as the socket opener app has suid permissions sudo chown root:usrp `which usrp2_socket_opener` sudo chmod 04750 `which usrp2_socket_opener` -Josh On 04/21/2010 12:57 PM, George Nychis wrote: **NOTE** I do not get the import error when I do not run the command with sudo, but then I do not get the proper raw socket permissions. Maybe that rings a bell to someone? Something probably about an environment variable I am missing. actually... I am getting the same error now without using sudo, so that doesn't seem to be a difference - George ___ 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] How to solve the USRP overrun problem
Dear all, I'm modifying the gr-sounder project to transmit a 113-bit legendre sequence of the bandwith 32kHz and upconvert to certain frequency in the range 1MHz to 20MHz. At receiver side, the received signal is downconverted to baseband and store the recovered sequence into a data file. I modified the FPGA configuration by using clk_divider to downconvert the clock, clk64 to 32kHz, and applied the 32kHz to module adc_interface, sounder,rx_buffer, dac_interface instead of clk64. The other modules still keep the chip-rate(clk64) as the working frequency. At the receiver side, I gt rid of the correlation part, made the receiver directly store the received data into rx_buffer. The result shows some USRP overrun signs (uO), and the received data is as shown below: -1 - 1i -1 + 0i 0 + 0i 0 + 0i 0 + 0i 0 - 1i -1 - 1i -1 - 1i -1 - 1i 0 + 0i 0 + 0i 0 + 0i 0 + 0i -1 - 1i -1 - 1i -1 - 1i -1 + 0i 0 + 0i 0 + 0i 0 + 0i However, the frequency of baseband data should be 32kHz, which doesn't exceed the maximum USB data rate 8MHz, why the USRP overrun? The received data should be the amplitude of the code, 4096, and the data should be real part only. What is the possible reason why the received data is as the shown. Thank you so much! Regards, Yan attachment: ynie3.vcf___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] freq_xlating_fir_filter_ccc
Ok, so I have an input audio chunk, from DC-48KHz, sampled at 96KHz. I want to extract 20KHz to 32KHz, and shift this down to DC (DC-12KHz). I think I need the freq_xlating_fir_filter_ccc() block, but I've seen conflicting information about how to use this block. In GRC, what parameters do I give to this block? The FIR filter is applied after downconversion, correct? But that filter runs at the *input* sample rate (prior to decimation) correct? If I want to grab 20KHz to 32KHz, do I tell the block that my center frequency is 26KHz? (20KHz + output_bandwidth/2)? Call me confused. -- 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] DPSK Modulator and Demodulator
You can't connect the file source directly to the Modulator. If you are Using DBPSK, the modulator will be looking for 1 bit at a time, or in this case a byte with only 1 significant bit. Use File Source packed to unpacked [1 bit per chunk] MSB first DBPSK Modulator Marcin David Barton-4 wrote: Hi, I am having trouble the the DBPSK mod and demod blocks. My flow graph is: file source - DBPSKmod - DBPSKdemod - file sink The file source is a 2 byte text file set to not repeat The default parameters were used for the DBPSKmod and demod blocks (including 2 Samples/Symbol) When I run the graph the output text file becomes 13 bytes long and they are almost all zeros. I am not sure how it gets to be that length. I tried connecting the ouput of the DBPSKmod directly to the file sink and the file size was 256 bytes. This matched my expectations based on: 2bytes input file * 8bits/byte * 1Symbol/bit * 2 complex samples/Symbol* 8bytes /complex sample = 256 byte output file. If anyone knows why the output file of the whole graph would be 13 bytes or if I am missing something please let me know. Thanks, Dave ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio -- View this message in context: http://old.nabble.com/DPSK-Modulator-and-Demodulator-tp28319509p28323241.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DPSK Modulator and Demodulator
My mistake, i didn't realise you were using the available DBPSK block. The Packed to Unpacked block is already part of this Modulator, so disregard my comment. Marcin marcin_w wrote: You can't connect the file source directly to the Modulator. If you are Using DBPSK, the modulator will be looking for 1 bit at a time, or in this case a byte with only 1 significant bit. Use File Source packed to unpacked [1 bit per chunk] MSB first DBPSK Modulator Marcin David Barton-4 wrote: Hi, I am having trouble the the DBPSK mod and demod blocks. My flow graph is: file source - DBPSKmod - DBPSKdemod - file sink The file source is a 2 byte text file set to not repeat The default parameters were used for the DBPSKmod and demod blocks (including 2 Samples/Symbol) When I run the graph the output text file becomes 13 bytes long and they are almost all zeros. I am not sure how it gets to be that length. I tried connecting the ouput of the DBPSKmod directly to the file sink and the file size was 256 bytes. This matched my expectations based on: 2bytes input file * 8bits/byte * 1Symbol/bit * 2 complex samples/Symbol* 8bytes /complex sample = 256 byte output file. If anyone knows why the output file of the whole graph would be 13 bytes or if I am missing something please let me know. Thanks, Dave ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio -- View this message in context: http://old.nabble.com/DPSK-Modulator-and-Demodulator-tp28319509p28323370.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] An Allocation Error
On Tue, Apr 20, 2010 at 10:09:03AM +, Umair Naeem wrote: I have made a flow graph in GRC and I am getting this error Generating: /home/salsa/top_block.py Executing: /home/salsa/top_block.py gr_fir_ccf: using SSE gr_vmcircbuf_sysv_shm: shmget (1): Invalid argument gr_buffer::allocate_buffer: failed to allocate buffer of size 21288 KB terminate called after throwing an instance of 'std::bad_alloc' what(): std::bad_alloc How Can I handle this error? Does make check succeed? Regards, Umair Naeem MSc Communication Engineering Chalmers University ot Technology, Sweden. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Freeze when writing to linux fifo pipe
On Tue, Apr 20, 2010 at 02:57:04PM +0200, Joachim Roop wrote: Hi, I am trying to write to a linux pipe/fifo, but sadly this seems to freeze python. I am using Ubuntu 10.04 and gnuradio 3.2.2.dfsg-1ubuntu1. Please try to execute the code and tell me why this makes the app pause. $ man 3 mkfifo Opening a fifo for reading blocks until there is a writer and vice versa... Eric #! /usr/bin/python # Import stuff from gnuradio import gr, gru, eng_notation, optfir from gnuradio.eng_option import eng_option from gnuradio.wxgui import slider, powermate from gnuradio.wxgui import stdgui2, fftsink2, form, scopesink2 import sys import os # Main application class main_app (stdgui2.std_top_block): def __init__(self,frame,panel,vbox,argv): stdgui2.std_top_block.__init__ (self,frame,panel,vbox,argv) print '!!!Cleanup' os.spawnlp(os.P_WAIT, 'rm', 'rm','/tmp/gnutest1.raw') os.spawnlp(os.P_WAIT, 'rm', 'rm','/tmp/gnutest2.raw') print '!!!make a fifo' os.spawnlp(os.P_WAIT, 'mkfifo', 'mkfifo','/tmp/gnutest1.raw') print '!!!make file sink without the fifo' outok = gr.file_sink(gr.sizeof_short,'/tmp/gnutest2.raw') print '!!!make file sink with the fifo (FREEZING)' outcrash = gr.file_sink(gr.sizeof_short, '/tmp/gnutest1.raw') print '!!!everything went better than expected' if __name__ == '__main__': app = stdgui2.stdapp (main_app, crashtest) app.MainLoop () ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Freeze when writing to linux fifo pipe
On 04/21/2010 11:26 PM, Eric Blossom wrote: On Tue, Apr 20, 2010 at 02:57:04PM +0200, Joachim Roop wrote: Hi, I am trying to write to a linux pipe/fifo, but sadly this seems to freeze python. I am using Ubuntu 10.04 and gnuradio 3.2.2.dfsg-1ubuntu1. Please try to execute the code and tell me why this makes the app pause. $ man 3 mkfifo Opening a fifo for reading blocks until there is a writer and vice versa... Eric Actually, an open for read will *always* succeed, lest you create unpleasant deadlock situations... -- 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] Freeze when writing to linux fifo pipe
On Wed, Apr 21, 2010 at 11:30:32PM -0400, Marcus D. Leech wrote: On 04/21/2010 11:26 PM, Eric Blossom wrote: On Tue, Apr 20, 2010 at 02:57:04PM +0200, Joachim Roop wrote: Hi, I am trying to write to a linux pipe/fifo, but sadly this seems to freeze python. I am using Ubuntu 10.04 and gnuradio 3.2.2.dfsg-1ubuntu1. Please try to execute the code and tell me why this makes the app pause. $ man 3 mkfifo Opening a fifo for reading blocks until there is a writer and vice versa... Eric Actually, an open for read will *always* succeed, lest you create unpleasant deadlock situations... Hmmm. FWIW, from Linux: man 3 mkfifo Opening a FIFO for reading normally blocks until some other process opens the same FIFO for writing, and vice versa. See fifo(7) for non-blocking handling of FIFO special files. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Clearly, I got gr.freq_xlating_fir_filter_ccc working!
Well, after a little bit of mucking about, I was able to down-shift the segment I needed into a range that is audible to the human ear. Here's a snippet: http://www.sbrac.org/files/vlf.mp3 (I have it in FLAC and OGG and WAV as well, just figured most folks would have a MP3 player :-) ). It's about 40 seconds of a segment of the VLF band, between 23KHz and 28KHz, downshifted so that 23KHz is at DC. The dominant tone is the U.S. Navy VLF station called NAA, located in Cutler, Maine, about 850km from me. Down in the mud, there's also the NML station that is in North Dakota, about 1600km from me. The clicks 'n pops are 'spherics mostly caused by distant lightning. I pre-process the entire input bandwidth (DC-48KHz) to remove *all* harmonics of 60Hz, prior to doing anything else with it. That cleans up the spectrum considerably! The RMS signal power for up to 4 narrow-band VLF stations is also recorded in real-time, to measure ionospheric absorption. Doing this audio-shifting trick was more for amusement than any scientific value. The whole digital portion of the signal processing chain is done in Gnu Radio. I have a magnetic loop antenna outside the house, about 300' of wire wound onto a 1.8M square frame, and I'm using a cheap Behringer microphone pre-amp as a low-noise amplifier in front of the sound card. If the sound card was a little quieter, I wouldn't need the pre-amp, but there's just a little too much noise on the card to allow the signals to be really clean, so an audio pre-amp for VLF radio signals! Cheers -- 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
