Re: [Discuss-gnuradio] GNU Radio OFDM Theori
Eric Blossom wrote: > > > There is no documentation of that type for OFDM. > > Eric > > if i want to reconfigure the modulation for each sub-carrier (bit loading for OFDM), can i just edit the ofdm benchmark python file? or i have to go in detail until the IFFT and FFT? the OFDM that GNU Radio have currently i think it already have the CP (cyclic prefix) right? eric can you please tell me how the IFFT and FFT is being constructed? or how the OFDM is being made in GNU Radio? what references they use? i found this presentation slide ( http://www.nabble.com/file/p22735812/gr_ofdm.rar gr_ofdm.rar ).. i hope it is usefull for those who are working in the same area as me. but i think this meterial is not enough .. so any body had more documentation please help me.. thank you. -- View this message in context: http://www.nabble.com/GNU-Radio-OFDM-Theori-tp22697706p22735812.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
[Discuss-gnuradio] modulation settings in python
Hi all, We are planning to do different modulation schemes with tunnel.py in gnuradio-example. In the script there's -m option to change the modulation. We use sudo ./tunnel.py --freq 2.44G --bitrate 500k -m dbpsk -v, but the two PC can't ping each other after virtual IP setup. This is the output of the script (on the sender side): >>> gr_fir_ccf: using SSE bits per symbol = 3 Gray code = True RS roll-off factor = 0.35 Using TX d'board A: Flex 2400 Tx MIMO B Tx amplitude 12000 modulation: d8psk_mod bitrate: 499.998kb/s samples/symbol:2 interp: 384 Tx Frequency:2.44G Demodulator: bits per symbol: 3 Gray code: True RRC roll-off factor: 0.35 Costas Loop alpha: 1.50e-01 Costas Loop beta:5.62e-03 M&M mu: 0.50 M&M mu gain: 1.75e-01 M&M omega: 2.00 M&M omega gain: 7.66e-03 M&M omega limit: 0.01 Receive Path: Using RX d'board A: Flex 2400 Rx MIMO B Rx gain: 45 modulation: d8psk_demod bitrate: 499.998kb/s samples/symbol:2 decim: 192 Rx Frequency:2.44G modulation: d8psk freq: 2.44G bitrate:499.998kb/sec samples/symbol: 2 Carrier sense threshold: 30 dB After ifconfig setup, both sender and receiver have output like: Tx: len(payload) = 192 Tx: len(payload) = 192 Tx: len(payload) = 105 But these two PCs can't ping each other. Are there other parameter settings for dbpsk? Thanks a lot! Yanyan -- View this message in context: http://www.nabble.com/modulation-settings-in-python-tp22735582p22735582.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
[Discuss-gnuradio] Re: uses gr.file_sink 32 bit or 64 bit
Eric Blossom schrieb: On Thu, Mar 26, 2009 at 07:32:09AM -0700, Johnathan Corgan wrote: On Thu, Mar 26, 2009 at 4:12 AM, feldmaus wrote: i want to save some output from the usrp and watch it with octave. The usrp.source_c(...) block generates IQ data as pairs of 32-bit floating point values. Or to avoid any confustion about how many samples are getting generated, I think it's easier to think that it generates samples that are of type std::complex. Eric Yes its confusing me. :-( Ok, here is a clipping from the data at the beginning: 0 + 0i 0 + 0i -1 + 0i 0 - 1i -13 + 2i 65 -32i -183 +98i 412 - 233i -831 + 478i 1572 - 918i -3050 + 1745i 8314 - 4139i -12548 - 5491i 3899 + 10329i 3523 - 2748i -1791 + 1379i 951 - 738i -484 + 378i 219 - 176i -84 +69i 19 -20i 0 + 0i 0 - 1i 0 + 0i 0 - 1i 0 + 0i 0 - 1i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 + 0i 0 - 1i 0 + 0i -1 - 1i 0 + 0i -1 - 1i 0 + 0i -1 - 1i 0 + 0i -1 + 0i 0 - 1i 0 + 0i -1 - 1i 0 + 0i -1 + 0i 0 - 1i -1 + 0i How can i collect bits from the I or Q Signal ? So the first 16 bits from the left side are the I Signal ? And the first 16 bits from the right side are the Q Signal ? Where is the beginning of the samples ? Maybe the curious values at the beginning is the start point ? Regards Markus ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: uses gr.file_sink 32 bit or 64 bit
Eric Blossom schrieb:
On Thu, Mar 26, 2009 at 07:32:09AM -0700, Johnathan Corgan wrote:
On Thu, Mar 26, 2009 at 4:12 AM, feldmaus wrote:
i want to save some output from the usrp and watch it with octave.
The usrp.source_c(...) block generates IQ data as pairs of 32-bit
floating point values.
Or to avoid any confustion about how many samples are getting
generated, I think it's easier to think that it generates samples that
are of type std::complex.
Eric
Thanks for your posts,
so if i really want to plot this data
in octave i have to collect every 32bit samples ?
If i only plot the vector containnig the float samples:
c=read_complex_binary('usrp_output_64bit_complex_only_sin_signal.dat');
t=1:1:100;
plot([real(c(t)), imag(c(t))])
i got for the beginning,
http://img90.imageshack.us/my.php?image=from1to100bits.jpg
And if i do,
t=100:1:164;
plot([real(c(t)), imag(c(t))])
http://img90.imageshack.us/my.php?image=from100to164bits.jpg
Regards Markus
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Re: [Discuss-gnuradio] usrp_wxapt_rcv.py
I am the author. The bandwidth of the signal transmitted from the APT satellites (NOAA) is 30 kHz but this does not allow for doppler. The basic RX is almost wholly inappropriate for NOAA APT and for anything band pass sampling application without appropriate filtering. Operating a 60-ism MHz sample rate A/D means the Nyquist frequency is 30-ish Mhz. So all of the signals you are talking about are done with undersampling, using aliasing. But, FM transmitter are extremely strong. APT are NOT. All of the noise that is in every 30-ish MHz segment up and beyond are folded down on top of the signal of interest. This is less important in FM than in weak signal satellite work. I never considered that anyone would do this or I would have tested for the presence of an appropriate tuner or an override be asserted. Bob Patrik Tast wrote: Hi All, My name is Patrik Tast from Vasa, Finland. I this week received the Ettus USRP with daughterboards BasicRX and 800-2400 MHz RX from CA, US. I fired it up today to test the BasicRX side using the usrp_wfm_*.py and nbfm and everything works as expected. I am able to hear what ever FM channels with great quality. Since I am a wxapt guy, http://www.poes-weather.com/, the usrp_wxapt_rcv.py was my next test in the examples directory. NOAA 17 @ 137.62 MHz was here just (usrp_wxapt_rcv.py -f 137.62e6 -V 0) and all I could hear was German radio comming through. Extremly faintly, I could hear the TICK-TOCK sound in the background (I also could have been imagining, it was so unclear) and (just) some change in the graph while the satellite was over me (45 degrees). When I changed to the R2FX-receiver (dedicated APT-receiver) the signal is there http://www.df2fq.de/english_version/r2fx_eng.html I could not find an author to the usrp_wxapt_rcv.py nor could I find a GRC block diagram for it. I can see that the author is aiming for 32 kHz bandwith but I suspect there is something missing? APT spec is at http://www2.ncdc.noaa.gov/docs/klm/html/c4/sec4-2.htm I'm using Fedora 9 and GnuRadio 3.1.3 (latest stable release, not from svn) Any help appreciated, Thanks, Patrik ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio -- (Co)Author: DttSP, Quiktrak, PowerSDR, GnuRadio Member: ARRL, AMSAT, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. "It is human nature to think wisely and act in an absurd fashion.", Anatole France. Twitter:rwmcgwier Active: Facebook,Myspace,LinkedIn ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP + RFX2400 - Emitting power control
Hello everybody, I am currently working with USRP and RFX2400, and I would like to have accurate control over the power that I am emitting. Actually, I have seen that: -> the gain parameter does not have any impact (gain_range[gmin,gmax,step] = [0,0,1]) -> the power level is somehow controlled by the amplitude parameter And my questions are: - What is the ""exact maximum"" of the amplitude to reach the specified maximal power of 17dBm (50mW)? (Is that 16000?) - By the way, what is the relationship between amplitude and power? Is "power = coefficient * (amplitude)2"? Or is the power only proportional to what the board can/decides to provide as Voltage * Intensity at the antenna? - In the o'scope utility provided by the sources, what are the two signals I can observe when using 1 card/1 antenna? Are these two signals Q and I? What are the y-axis units? Is it an expression of the power or of the amplitude (like sqrt(2)*amplitude, but with one zero missing)? Thank you in advance for your support, Arthur Schmitt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: Tx & Rx in one USRP
On Thu, Mar 26, 2009 at 09:56:13PM +0100, William Sherman wrote:
> Also I have looked at code where there is no top block ("Exploring
> GnuRadio"). Instead a flowgraph is created using gr.flow_graph(). Can I
> just create and execute multiple flowgraphs using this method?
That document is out of date, and there's an open ticket to fix it.
Eric
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[Discuss-gnuradio] Re: Tx & Rx in one USRP
Thank you, I understand there can only be one top block, but it can have
multiple flowgraphs inside it.
What if I wanted to change the parameters of just one of the flowgraphs
during runtime? Would I need to kill off the whole top block, create
another one with changes made to the one flowgraph, then start it up
again? I just want to change the one flowgraph.
How do you "kill" a thread or flowgraph in python anyway?
Also I have looked at code where there is no top block ("Exploring
GnuRadio"). Instead a flowgraph is created using gr.flow_graph(). Can I
just create and execute multiple flowgraphs using this method?
--
Posted via http://www.ruby-forum.com/.
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Re: [Discuss-gnuradio] GNU Radio Packets
On Thu, Mar 26, 2009 at 04:01:58PM -0400, devin kelly wrote: > Thanks for the help. > > How close is GNU radio to implementing VITA49/UDP? Is the release weeks > away, months away, or more? What version number do you think that will be? Months away. We're currently tracking the VRT tickets with their own release milestone, usrp2-vrt. When we know more about how it's coming together with regard to the rest of the GNU Radio development, we'll assign it to a numbered release. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GNU Radio Packets
Thanks for the help. How close is GNU radio to implementing VITA49/UDP? Is the release weeks away, months away, or more? What version number do you think that will be? Thanks again, Devin On Thu, Mar 26, 2009 at 10:47 AM, Johnathan Corgan < jcor...@corganenterprises.com> wrote: > 2009/3/26 devin kelly : > > > I am trying to figure out how information is sent between a PC and the > > USRP. So far I can tell they are all customized packets, i.e. raw > sockets > > are used, which is why you need to be root. > > The USRP2 currently uses Ethernet frames of type 0xBEEF to communicate > sample data and control frames with the host PC. > > > But I've been having trouble > > figuring out what the header information is. > > The wire format is described here: > > > http://gnuradio.org/trac/browser/gnuradio/trunk/usrp2/firmware/include/usrp2_eth_packet.h > > > > If there is > > a GNU Radio plugin for Wireshark (formerly Ethereal) that would be a > great > > tool. > > That would be a welcome addition to the project. > > > Also, does the USRP (or USRP2) support UDP at all? > > It currently does not. However, after release 3.2, we are rewriting > the USRP2 transport format to use the VITA49 digital IF standard, > encapsulated in UDP. > > Johnathan > -- http://users.wpi.edu/~dkelly/ ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] gnuradio + VM
Is a normal message? Gnuradio will work fine? thanks 2009/3/26 Eric Blossom > On Thu, Mar 26, 2009 at 03:21:59PM -0300, Paulo Benatto wrote: > > during the make check occurs > > > > Testing gr_vmcircbuf_createfilemapping_factory... > > gr_vmcircbuf_createfilemapping: createfilemapping is not available > > ... gr_vmcircbuf_createfilemapping_factory: Doesn't work > > Testing gr_vmcircbuf_sysv_shm_factory... > > ... gr_vmcircbuf_sysv_shm_factory: OK > > Testing gr_vmcircbuf_mmap_shm_open_factory... > > ... gr_vmcircbuf_mmap_shm_open_factory: OK > > Testing gr_vmcircbuf_mmap_tmpfile_factory... > > ... gr_vmcircbuf_mmap_tmpfile_factory: OK > > gr_vmcircbuf_createfilemapping: createfilemapping is not available > > > > 2009/3/26 Eric Blossom > > > > This is OK. > > Eric > -- Paulo Leonardo Benatto, patito "the fear of being free makes you proud of being a slave" ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] QAM8 demod error in GRC
On Thu, Mar 26, 2009 at 03:13:51PM -0400, w w wrote: > I'm setting up in GRC a QAM8 Demod and am getting the following error: > > /blk2impl/qam8.py line 195, in_init_ > gr.io_signature(1,1, gr.sizeof_gr_char)) > > Attribute Error: 'Module' object has no attribute 'sizeof_gr_char' > > Any suggestions? It's fixed in the trunk in r10691. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] QAM8 demod error in GRC
I'm setting up in GRC a QAM8 Demod and am getting the following error: /blk2impl/qam8.py line 195, in_init_ gr.io_signature(1,1, gr.sizeof_gr_char)) Attribute Error: 'Module' object has no attribute 'sizeof_gr_char' Any suggestions? Cheers, Jody ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP Receiver config problem
On Thu, Mar 26, 2009 at 01:24:37PM -0400, satar...@eden.rutgers.edu wrote: > Hi, > > I am trying to run ALOHA MAC on gnu radio. The modulation scheme used is > GMSK. The Tx and Rx chains are as follows: > > Tx Chain: > > src -> framer -> crc enoder -> fec encoder -> preamble -> nrz -> > interpolator -> Gauus filter -> FM modulator -> gain -> usrp_tx > > Rx Chain > > usrp_rx -> filter -> demod -> integrator filter -> correlator -> fec > decoder -> crc decoder -> extract frame > > For some reason, I am unable to receive the frame when I run my python > scripts. I tested USRP boards by passing a simple sine-wave and it is > received correctly. I checked the output of usrp_tx on oscilloscope and it > does display the frame going through. To test, whether there was any > problem in the signalblocks I replaced usrp_tx by a filesink and dumped > the output of Tx chain in a file. I replaced the usrp_rx by this file and > the frame was correctly received. I think this means that there is problem > of configuration with usrp_tx and usrp_rx. Following are the configuration > scripts: How are you doing symbol timing recovery on the receiver? Generating logging data using gr.file_sink's at varous points in the graph is often helpful in seeing what's going on. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] gnuradio + VM
On Thu, Mar 26, 2009 at 03:21:59PM -0300, Paulo Benatto wrote: > during the make check occurs > > Testing gr_vmcircbuf_createfilemapping_factory... > gr_vmcircbuf_createfilemapping: createfilemapping is not available > ... gr_vmcircbuf_createfilemapping_factory: Doesn't work > Testing gr_vmcircbuf_sysv_shm_factory... > ... gr_vmcircbuf_sysv_shm_factory: OK > Testing gr_vmcircbuf_mmap_shm_open_factory... > ... gr_vmcircbuf_mmap_shm_open_factory: OK > Testing gr_vmcircbuf_mmap_tmpfile_factory... > ... gr_vmcircbuf_mmap_tmpfile_factory: OK > gr_vmcircbuf_createfilemapping: createfilemapping is not available > > 2009/3/26 Eric Blossom > This is OK. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] gnuradio + VM
during the make check occurs Testing gr_vmcircbuf_createfilemapping_factory... gr_vmcircbuf_createfilemapping: createfilemapping is not available ... gr_vmcircbuf_createfilemapping_factory: Doesn't work Testing gr_vmcircbuf_sysv_shm_factory... ... gr_vmcircbuf_sysv_shm_factory: OK Testing gr_vmcircbuf_mmap_shm_open_factory... ... gr_vmcircbuf_mmap_shm_open_factory: OK Testing gr_vmcircbuf_mmap_tmpfile_factory... ... gr_vmcircbuf_mmap_tmpfile_factory: OK gr_vmcircbuf_createfilemapping: createfilemapping is not available 2009/3/26 Eric Blossom > On Thu, Mar 26, 2009 at 10:13:22AM -0300, Paulo Benatto wrote: > > I have installed gnuradio in Virtual Machine (CentOS 5), when i try to > make > > a program using python i get this error: > > > > [ERROR]= > > gr_vmcircbuf_createfilemapping: createfilemapping is not available > > === > > > > This problem occurs because I'm using VM? > > > Does this occur during "make check"? > > If so, does "make check" complete succuessfully? > > Eric > -- Paulo Leonardo Benatto, patito "the fear of being free makes you proud of being a slave" ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] DBPSK and Carrier Suppressed or Not?
As another follow up, I fixed the garbled text problem by putting an AGC block on the RX side. On Fri, Mar 20, 2009 at 10:57 AM, w w wrote: > As a follow upI did some popping and swapping and found that the RFX > 900 board was bad. I put in a RFX 2400 card and the the very pronouced > carrier I saw before dissappeared and the signal transmitted out of the RFX > brd looked liked the signal coming out of the modulator. I was able send a > text file over the RFX brd and rx it on the other side. I guess there is > nothing that can be done to bring the other board back online...I didn't see > any pots on it. > > Even though I was able to transmit a text file, parts of it was garbled on > the other end.any suggestions for tighting things up to take out the > garble? This test took place on one usrp with two RFX 2400 brds and using a > cable to connect the transmit side of one card to the receive side of the > other card. I will next try between two usrps via coax and then OTA. > > Also I had to take out the channel filter because the signal out of > it would start up and then would die after about 10 to 20 seconds ( Channel > filter = FFT filter -> Decimanation=1, TAPS = lowpass(1,2,1, .5, > WIN_HAMMING)) With the RFX 900 I was tranmitting at 800Mhz and with the RFX > 2400 I'm tranmitting at 2.5 GHz...Mod - DBPSKAny thoughts or > suggestions? > > Cheers, > Jody > > On Wed, Mar 18, 2009 at 5:23 PM, Bill Stevenson < > bill.stevenso...@yahoo.com> wrote: > >> >> >> -- >> *From:* Eric Blossom >> *To:* w w >> *Cc:* discuss-gnuradio@gnu.org >> *Sent:* Wednesday, March 18, 2009 4:30:04 PM >> *Subject:* Re: [Discuss-gnuradio] DBPSK and Carrier Suppressed or Not? >> >> On Wed, Mar 18, 2009 at 02:55:41PM -0400, w w wrote: >> > I'm putting together a DBPSK Tx and Rx and running into problems when >> the >> > modulated signal hits the USRP. When I receive the signal on the USRP >> > there's a very pronouced carrierI've confirmed with a spectrum >> analyser >> > that the signal on the FFT is the one that I'm recieving. It seems to >> me >> > that the sidebands should be close to the highest amplitute and the >> carrier >> > should be suppressed.is this correct? Shouldn't the output of the >> DPSK >> > modulator FFT plot look very similar to the FFT plot on the RX side of >> the >> > usrp? I'm modeling the block connections after the benchmark samples in >> > the digital example section. I put a channel filter inline with the >> usrp >> > and the dpsk demod block just like the example.do I need to put more >> > filtering in place to suppress the carrier? If so, do you have any >> > examples? >> >> > If I take the output of the modulator and go directly to the demod thru >> the >> > channel filter, data flows just fine(bypassing the usrp). >> > >> > I'm only using one usrp and taking the output of the TX via coax and >> going >> > into the RX side...that shouldn't make a difference should it? >> >> > Any thoughts? >> > >> > Cheers, >> > Jody >> >> Before writing your own, did you take a look at the implementation of >> dbpsk that's already in the tree? >> >> See the -m dbpsk option below >> >> >> $ ./benchmark_tx.py --help >> Usage: benchmark_tx.py [options] >> >> Options: >> -h, --helpshow this help message and exit >> -m MODULATION, --modulation=MODULATION >> Select modulation from: cpm, d8psk, qam8, dbpsk, >> dqpsk, gmsk [default=gmsk] >> -s SIZE, --size=SIZE set packet size [default=1500] >> -M MEGABYTES, --megabytes=MEGABYTES >> set megabytes to transmit [default=1.0] >> --discontinuous enable discontinous transmission (bursts of 5 >> packets) >> --from-file=FROM_FILE >> use file for packet contents >> -f FREQ, --freq=FREQ set Tx and/or Rx frequency to FREQ >> [default=none] >> -r BITRATE, --bitrate=BITRATE >> specify bitrate. samples-per-symbol and interp/decim >> will be derived. >> -w WHICH, --which=WHICH >> select USRP board [default=0] >> -T TX_SUBDEV_SPEC, --tx-subdev-spec=TX_SUBDEV_SPEC >> select USRP Tx side A or B >> --tx-amplitude=AMPL set transmitter digital amplitude: 0 <= AMPL < >> 32768 >> [default=12000] >> -v, --verbose >> >> Expert: >> -S SAMPLES_PER_SYMBOL, --samples-per-symbol=SAMPLES_PER_SYMBOL >> set samples/symbol [default=none] >> --tx-freq=FREQ set transmit frequency to FREQ [default=none] >> -i INTERP, --interp=INTERP >> set fpga interpolation rate to INTERP [default=none] >> --log Log all parts of flow graph to file (CAUTION: lots >> of >> data) >> --use-whitener-offset >> make sequential packets use different whitening >> --excess-bw=EXCESS_BW >> se
[Discuss-gnuradio] USRP Receiver config problem
Hi, I am trying to run ALOHA MAC on gnu radio. The modulation scheme used is GMSK. The Tx and Rx chains are as follows: Tx Chain: src -> framer -> crc enoder -> fec encoder -> preamble -> nrz -> interpolator -> Gauus filter -> FM modulator -> gain -> usrp_tx Rx Chain usrp_rx -> filter -> demod -> integrator filter -> correlator -> fec decoder -> crc decoder -> extract frame For some reason, I am unable to receive the frame when I run my python scripts. I tested USRP boards by passing a simple sine-wave and it is received correctly. I checked the output of usrp_tx on oscilloscope and it does display the frame going through. To test, whether there was any problem in the signalblocks I replaced usrp_tx by a filesink and dumped the output of Tx chain in a file. I replaced the usrp_rx by this file and the frame was correctly received. I think this means that there is problem of configuration with usrp_tx and usrp_rx. Following are the configuration scripts: usrp_tx: cordic_freq =29.32e6 sw_interp = 8 usrp_interp = int (128e6 / sw_interp / data_rate) #160 fs = 128e6 / usrp_interp #128e6/160 = 800e3 u = usrp.sink_c (0, usrp_interp) u.set_tx_freq (0, cordic_freq) usrp_rx: r_cordic_freq = 29.32e6 # IF frequency r_data_rate = 40e3 r_samples_per_symbol = 8 r_usrp_decim = int (64e6 / r_samples_per_symbol / r_data_rate) # 80 r_fs = r_data_rate * r_samples_per_symbol # 800 e3 # initialize USRP r_u = usrp.source_c (0, r_usrp_decim) r_u.set_rx_freq (0, -r_cordic_freq) Can someone help me with this? thanks and regards, -Sumit ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GNU Radio OFDM Theori
On Wed, Mar 25, 2009 at 06:47:52PM -0700, adib_sairi wrote: > > Thank you Martin. but is there any detail on how OFDM in GNU Radio is > constructed like the documentation for FM recv ..in FM recv they explain > detail on how they construct the code.. what is the reson for each line and > what references that they used.. so in OFDM GNU Radio is there any > documentation like this? i thought bob is the leader for the GNU Radio OFDM > project (if i am not mistaken).. so bob or any body, can you please help me? > thank you.. There is no documentation of that type for OFDM. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] change connection during execution
top_block_gui inherits from a top block and wxgui window. It has all the methods of a top block. So you can do anything that a top block can. -Josh feldmaus wrote: Hi All, i ant to change my connections during execution. I found some interesting posts in this thread, but i have no flowgraph like in theses posts. I am using not the flowgraph class. How to do this ? Regards Markus ___ 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
Re: [Discuss-gnuradio] gnuradio + VM
On Thu, Mar 26, 2009 at 10:13:22AM -0300, Paulo Benatto wrote: > I have installed gnuradio in Virtual Machine (CentOS 5), when i try to make > a program using python i get this error: > > [ERROR]= > gr_vmcircbuf_createfilemapping: createfilemapping is not available > === > > This problem occurs because I'm using VM? Does this occur during "make check"? If so, does "make check" complete succuessfully? Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] uses gr.file_sink 32 bit or 64 bit
On Thu, Mar 26, 2009 at 07:32:09AM -0700, Johnathan Corgan wrote: > On Thu, Mar 26, 2009 at 4:12 AM, feldmaus wrote: > > > i want to save some output from the usrp and watch it with octave. > > The usrp.source_c(...) block generates IQ data as pairs of 32-bit > floating point values. Or to avoid any confustion about how many samples are getting generated, I think it's easier to think that it generates samples that are of type std::complex. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] tunnel.py buffer crash
On Wed, Mar 25, 2009 at 08:14:32PM -0700, yyzhuang wrote: > > Hi Eric, > > We've made a stupid mistake. My friend installed gnuradio from trunk in > their lab. I just figure out this problem. After we reinstalled there's no > buffer problem anymore. > > Thanks! > Yanyan Thanks for letting us know it's working. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GRC Error
Jonathan Anderson wrote: Hello all, I'm attempting to run GRC (grc-0.60-3.fc9.noarch) on an x86_64 machine running Fedora 9. My version of GNU Radio is 3.1.2-2.fc9.x86_64. Ha! A fedora package for grc. Amazing~! I have no idea about the error. grc 0.60 is a very old version of (we are up to 3.2rc1) Sorry for the trouble, but I suggest you install gnuradio trunk, 3.2 release branch, or 3.2rc1, they all come with grc bundled in. The problem should go away. -Josh ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] change connection during execution
Hi All, i ant to change my connections during execution. I found some interesting posts in this thread, but i have no flowgraph like in theses posts. I am using not the flowgraph class. How to do this ? Regards Markus ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] [Douglas BBN 802.11b] Porting code on USRP2 problems
Dear all,
I'm trying to port the Douglas BBN 802.11b code on the USRP2 working
with the last version of GNU-Radio (3.2SVN)
The last version of Douglas bbn 802.11b already work with hier_blok2 but
not with USRP2, so,
in order to do this porting I followed the recommendations below :
-
http://www.opensubscriber.com/message/discuss-gnuradio@gnu.org/9944619.html
- http://sdrblog.wordpress.com/2009/03/12/port-usrp1-code-to-usrp2/
I just have modified the files "bbn_80211b_tx.py" and
"bbn_80211b_transmit_path.py" because
it should be by means of these ones that we can access to USRP2.
I obtain the following error:
Traceback (most recent call last):
File "bbn_80211b_tx.py", line 108, in
main()
File "bbn_80211b_tx.py", line 72, in main
tb = my_block(options.interp, options.spb, options.barker)
File "bbn_80211b_tx.py", line 22, in __init__
self.txpath = bbn_80211b_transmit_path(interp_rate, spb, use_barker)
File
"/home/usrptest1/bbn_80211_doug/src/examples/bbn_80211b_transmit_path.py",
line 44, in __init__
self.packet_transmitter = bbn_80211b_mod_pkts(tb, spb=spb,
NameError: global name 'tb' is not defined
I am not able to solve this error and debug the new code :-(
Any suggestion about this porting will be welcome
Best regards Andrea
Here below there are my two modified codes:
##
# bbn_802.11b_tx.py
##
from gnuradio import gr, gru, blks2
from gnuradio import usrp2
from gnuradio import eng_notation
from gnuradio.eng_option import eng_option
from optparse import OptionParser
import random
import time
import struct
import sys
# from current dir
from bbn_80211b_transmit_path import bbn_80211b_transmit_path
class my_block(gr.top_block):
def __init__(self, interp_rate, spb, use_barker):
gr.top_block.__init__(self)
self.txpath = bbn_80211b_transmit_path(interp_rate, spb,
use_barker)
#def __init__(self, tx_subdev_spec, interp_rate, spb, use_barker):
# gr.flow_graph.__init__(self)
# self.txpath = bbn_80211b_transmit_path(tx_subdev_spec, \
#interp_rate, spb,
use_barker)
#
/
# main
#
/
def main():
def send_pkt(payload='', eof=False):
return tb.txpath.send_pkt(payload, eof)
def rx_callback(ok, payload):
print "ok = %r, payload = '%s'" % (ok, payload)
parser = OptionParser (option_class=eng_option)
#parser.add_option("-T", "--tx-subdev-spec", type="subdev",
default=None,
# help="select USRP Tx side A or B")
parser.add_option("-f", "--freq", type="eng_float", default=2.4e9,
help= \
"set Tx and Rx frequency to FREQ
[default=%default]",
metavar="FREQ")
parser.add_option("-S", "--spb", type="int", default=8,
help="set samples/baud [default=%default]")
parser.add_option("-i", "--interp", type="int", default=32,
help=
"set fpga interpolation rate to INTERP
[default=%default]")
parser.add_option("-r", "--reps", type="int", default=20,
help=
"Number of packets to send [default=%default]")
parser.add_option("-b", "--barker", action="store_true",
default=False,
help="Use Barker Spreading [default=%default]")
(options, args) = parser.parse_args ()
if len(args) != 0:
parser.print_help()
sys.exit(1)
if options.freq < 1e6:
options.freq *= 1e6
# build the graph
tb = my_block(options.interp, options.spb, options.barker)
#print "bitrate: %sb/sec" %
(eng_notation.num_to_str(tb.txpath.bitrate()),)
print "spb: %3d" % (tb.txpath.spb(),)
print "interp: %3d" % (tb.txpath.interp(),)
ok = tb.txpath.set_freq(options.freq)
if not ok:
print "Failed to set Tx frequency to %s" %
(eng_notation.num_to_str(options.freq),)
raise SystemExit
tb.start() # start flow graph
# generate and send packets
n = 0
fp = open('getty.txt')
lines = fp.readlines()
payload = ""
i = 0;
while i < len(lines):
payload = payload + lines[i]
i = i + 1
while n < options.reps:
send_pkt(payload, False);
Re: [Discuss-gnuradio] GNU Radio Packets
2009/3/26 devin kelly : > I am trying to figure out how information is sent between a PC and the > USRP. So far I can tell they are all customized packets, i.e. raw sockets > are used, which is why you need to be root. The USRP2 currently uses Ethernet frames of type 0xBEEF to communicate sample data and control frames with the host PC. > But I've been having trouble > figuring out what the header information is. The wire format is described here: http://gnuradio.org/trac/browser/gnuradio/trunk/usrp2/firmware/include/usrp2_eth_packet.h > If there is > a GNU Radio plugin for Wireshark (formerly Ethereal) that would be a great > tool. That would be a welcome addition to the project. > Also, does the USRP (or USRP2) support UDP at all? It currently does not. However, after release 3.2, we are rewriting the USRP2 transport format to use the VITA49 digital IF standard, encapsulated in UDP. Johnathan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] uses gr.file_sink 32 bit or 64 bit
On Thu, Mar 26, 2009 at 4:12 AM, feldmaus wrote:
> i want to save some output from the usrp and watch it with octave.
The usrp.source_c(...) block generates IQ data as pairs of 32-bit
floating point values.
Use gr.file_sink(gr.sizeof_gr_complex, "filename.dat") to write these
samples to disk.
Inside Octave, use read_complex_binary('filename.dat') to load the
saved samples into an array of complex numbers.
Johnathan
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Re: [Discuss-gnuradio] Error whle performing make check for gnuradio-3.2
2009/3/25 Somya Ajmera : > Hi Michael, thanks for replying. I did the following as suggested by you, > but now it is giving me the following error: > > Making all in lib > make[4]: Entering directory `/home/somya/gnuradio-3.2rc1/mblock/src/lib' > GUILE_LOAD_PATH="/home/somya/gnuradio-3.2rc1/pmt/src/scheme:/home/somya/gnuradio-3.2rc1/mblock/src/scheme" > /usr/bin/guile -e main -s > ../../../mblock/src/scheme/gnuradio/compile-mbh.scm ./qa_bitset.mbh > qa_bitset_mbh.cc > ERROR: no code for module (gnuradio macros-etc) What version of Guile do you have installed? $ guile --version Johnathan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] gnuradio + VM
I have installed gnuradio in Virtual Machine (CentOS 5), when i try to make a program using python i get this error: [ERROR]= gr_vmcircbuf_createfilemapping: createfilemapping is not available === This problem occurs because I'm using VM? -- Paulo Leonardo Benatto, patito "the fear of being free makes you proud of being a slave" ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] GNU Radio Packets
Hello, I am trying to figure out how information is sent between a PC and the USRP. So far I can tell they are all customized packets, i.e. raw sockets are used, which is why you need to be root. But I've been having trouble figuring out what the header information is. Does anyone know? If there is a GNU Radio plugin for Wireshark (formerly Ethereal) that would be a great tool. Also, does the USRP (or USRP2) support UDP at all? I doesn't look like it to me, but I'd like to be sure. And if not, why no support for UDP? Thanks, Devin ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] GRC Error
Hello all, I'm attempting to run GRC (grc-0.60-3.fc9.noarch) on an x86_64 machine running Fedora 9. My version of GNU Radio is 3.1.2-2.fc9.x86_64. When I attempt to run a graph, I get the following output: >>> Verbose: python: Python/ceval.c:2624: PyEval_EvalCodeEx: Assertion `tstate != ((void *)0)' failed. >>> Done I've Googled for this error, and it shows up in lots of C/Python software; no other commonality that I can immediately see. Help? Jon -- Jonathan Anderson Research Student, Security Group Computer Laboratory University of Cambridge +44 (01223) 763747 jonathan.ander...@cl.cam.ac.uk signature.asc Description: OpenPGP digital signature ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Multi antenna transmit with RFX2400
Hi, again
I should have precise that I'm mainly interested in some piece of
advise.
In fact, I found the test_mimo_tx.cc in the trunk but it is designed
for usrp2 and I'm not sure about how I can reuse from it.
I also had from other people the following code allowing me to
transmit on both antennas but I don't know what is transmitted on each
antenna as I don't clearly understand where is the separation between
the sides A and B.
How can I say for example which symbol goes on side A and how are side
A and B synchronised when sending different symbol on each ?
int main(int argc,char **argv)
{
unsigned int i1;
unsigned int InterpRate;
unsigned int nchannels, DdcFreq, LOFreq, gain;
unsigned long RF_freq;
usrp_standard_rx_sptr rx0, rx1;
usrp_standard_tx_sptr tx0, tx1;
db_flexrf_mimo db_aside0,db_bside0;
db_flexrf_mimo db_aside1,db_bside1;
struct sched_param sp;
number_of_buffers_wanted=atoi(argv[1]);
if (number_of_buffers_wanted>MAX_NUMBER_OF_BUFFERS)
number_of_buffers_wanted=MAX_NUMBER_OF_BUFFERS;
if (number_of_buffers_wanted<2)
number_of_buffers_wanted=2;
RF_freq=atof(argv[2]);
gain=atoi(argv[3]);
InterpRate=16;
rx0 = usrp_standard_rx::make(0, InterpRate);
tx0 = usrp_standard_tx::make(0,InterpRate*2,2,47768); //0xBA98 0b
1011 1010 1001 1000
if (1) {
unsigned int counter=0;
bool underrun;
if(gruel::enable_realtime_scheduling()!=gruel::RT_OK){
printf("Problems enabeling realtime scheduling!!!\n");
}
db_aside0=db_flexrf_mimo(rx0,tx0,0);
db_bside0=db_flexrf_mimo(rx0,tx0,1);
db_aside0.configure_tx(0);
db_aside0.tune_tx(RF_freq,0);
db_bside0.configure_tx(0);
db_bside0.tune_tx(RF_freq,0);
db_aside0.set_tx_auto_tr(true);
db_bside0.set_tx_auto_tr(true);
tx0->set_nchannels(2);
ifstream l("data_to_usrp.dat", ios::binary);
int i1;
for (i1=0;i1start();
while (1) {
tx0->write((void *) CollectedData[counter++%
number_of_buffers_wanted],
NUMBYTES,&underrun);
if (underrun)
cout << "Underrrun \n";
};
};
Le 24-mars-09 à 09:54, Jérémy Skelton a écrit :
Hi,
I was wondering how I can transmit synchronously on two antenna
using two RFX2400 on the same USRP1 motherboard.
It should be possible as the daugtherboards are MIMO capable but
does anyone have some c++ working piece of code ?
My goal is to implement an Alamouti scheme for diversity transmission.
Thanks,
Jérémy
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Re: [Discuss-gnuradio] Multi antenna transmit with RFX2400
Hi, again
I should have precise that I'm mainly interested in some piece of
advise.
In fact, I found the test_mimo_tx.cc in the trunk but it is designed
for usrp2 and I'm not sure about how I can reuse from it.
I also had from other people the following code allowing me to
transmit on both antennas but I don't know what is transmitted on each
antenna as I don't clearly understand where is the separation between
the sides A and B.
How can I say for example which symbol goes on side A and how are side
A and B synchronised when sending different symbol on each ?
int main(int argc,char **argv)
{
unsigned int i1;
unsigned int InterpRate;
unsigned int nchannels, DdcFreq, LOFreq, gain;
unsigned long RF_freq;
usrp_standard_rx_sptr rx0, rx1;
usrp_standard_tx_sptr tx0, tx1;
db_flexrf_mimo db_aside0,db_bside0;
db_flexrf_mimo db_aside1,db_bside1;
struct sched_param sp;
number_of_buffers_wanted=atoi(argv[1]);
if (number_of_buffers_wanted>MAX_NUMBER_OF_BUFFERS)
number_of_buffers_wanted=MAX_NUMBER_OF_BUFFERS;
if (number_of_buffers_wanted<2)
number_of_buffers_wanted=2;
RF_freq=atof(argv[2]);
gain=atoi(argv[3]);
InterpRate=16;
rx0 = usrp_standard_rx::make(0, InterpRate);
tx0 = usrp_standard_tx::make(0,InterpRate*2,2,47768); //0xBA98 0b
1011 1010 1001 1000
if (1) {
unsigned int counter=0;
bool underrun;
if(gruel::enable_realtime_scheduling()!=gruel::RT_OK){
printf("Problems enabeling realtime scheduling!!!\n");
}
db_aside0=db_flexrf_mimo(rx0,tx0,0);
db_bside0=db_flexrf_mimo(rx0,tx0,1);
db_aside0.configure_tx(0);
db_aside0.tune_tx(RF_freq,0);
db_bside0.configure_tx(0);
db_bside0.tune_tx(RF_freq,0);
db_aside0.set_tx_auto_tr(true);
db_bside0.set_tx_auto_tr(true);
tx0->set_nchannels(2);
ifstream l("data_to_usrp.dat", ios::binary);
int i1;
for (i1=0;i1start();
while (1) {
tx0->write((void *) CollectedData[counter++%
number_of_buffers_wanted],
NUMBYTES,&underrun);
if (underrun)
cout << "Underrrun \n";
};
};
Le 24-mars-09 à 09:54, Jérémy Skelton a écrit :
Hi,
I was wondering how I can transmit synchronously on two antenna
using two RFX2400 on the same USRP1 motherboard.
It should be possible as the daugtherboards are MIMO capable but
does anyone have some c++ working piece of code ?
My goal is to implement an Alamouti scheme for diversity transmission.
Thanks,
Jérémy
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[Discuss-gnuradio] Re: USRP - underflow / overflow problem
Narayanan, Sivaramasubramanian (R&T Honeywell.com> writes: > As soon as I run the program, I get messages like > > uUuUuUuUuUuUuUuUuUuUuUuUuUuOuOuUuOuUuOuOuUuUuOuUuUuOuOuOuUuU Hi, in the gnuradio docu is something written about "latency". Maybe this could fit up your program to solve this. But before this you should fit up your decimation value. Since i use the correct decimation value i doesn't get anymore this message. Try to use as small bandwidth as you need. The bandwidth of the signal used is determined by the decimation. The bandwidth of the signal relates to the transfer speed. But i am not 100% sure. Regards Markus ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Re: uses gr.file_sink 32 bit or 64 bit
I also want to save only as much data as needed to create ONE FFT-Plot in octave. My FFT-sink has got a fft-size of 1024. How to cut the stream for a fft-size of 1024 ? Regards Markus ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] uses gr.file_sink 32 bit or 64 bit
Hi All again, :-) i want to save some output from the usrp and watch it with octave. Therefor i know is something written at, http://gnuradio.org/trac/wiki/Octave quotation: "Data captured directly from the USRP is stored as 32-bit complex, rather than 64-bit complex (gr.sizeof_gr_complex)" So i think, gr.file_sink(gr.sizeof_gr_complex*1, "capture.dat") is to save 64 bit data and, gr.file_sink(gr.sizeof_short*1, "capture.dat") is to save 32 bit data. Is that correct ? But therefor i have to set the output type of my USRP to short(is not default) ? If i set the output type to complex then i would get 64 bit ? USRP source Ouput Type complex --> 64 bit USRP source Ouput Type short --> 32 bit Is this correct ? Regards Markus ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP - underflow / overflow problem
Hi, I am using the USRP board with two Basic Tx boards in both the Tx slots. I am also using both the Rx slots with Basic Tx on A side and TVRX on B side. I am using Tx side interpolation rate as 400 and Rx side decimation rate as 250. I am using a GUI with one button control to enable the Tx board and also a scopesink to plot the received waveform. I am using NBFM Tx/Rx blocks, filter blocks etc. I am using both the Tx and Rx parallely with each Tx/Rx pair tuned to different frequency (100 MHz and 150Mhz) As soon as I run the program, I get messages like uUuUuUuUuUuUuUuUuUuUuUuUuUuOuOuUuOuUuOuOuUuUuOuUuUuOuOuOuUuUuUuUuUuUuUuUuUuUuUuU uUuUuUuUuUuUuUuUuUuUuUuUuUuUuUuUuUuUuUuOuOuUuUuUuOuOuUuUuUuUuUuUuUuOuOuUuUuOuUuO uOuUuUuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuUuUuUuUuUuUuOuU uUuOuUuUuOuUuUuUuUuUuUuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuOuO. Please let me know what goes wrong and how to get rid of this problem. Thanks and Regards, Sivaram ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] SDR Forum at Dayton Hamvention
The SDR Forum at the Dayton Hamvention is Saturday 11:15 AM to 1:30 PM May 16. This is the ARRL National convention as well so it should be well attended. Because of missed emails, etc. (I was left off the email addressees so I got none of the emails) we are now in a rush. The initial list, etc. is supposed to be in DARA hands by April 1. This needs to be dealt with ASAP. I will contact some "you should" directly but I am soliciting 15-20 minute talks. I need at least an indiciation of willingness to speak, a few sentence abstract, and your willingness to be flexible in the timing as Irush this together. Thanks Bob McGwier ARS N4HY ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
