Re: [Discuss-gnuradio] AX.25 and USRP? gr-multimon?
Hi, Check : http://digilander.libero.it/iz2eeq/ Regards, Firas A. James Cutler [EMAIL PROTECTED] wrote: Hello, Does anyone know of any code for the USRP/Gnuradio to decode AX.25 packets? I've seen threads of this conversation from several years ago but can't seem to find any code to implement this. gr-multimon seems to be a tool that might do it, but I can't find it anywhere. Thanks for your help. --James ___ 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] Real-world sample data
Does anyone have any UK analog UHF TV sample data? Just before they turn it off ... Thanks D On Wednesday 13 February 2008 18:19:26 Michael Gray wrote: http://kd7lmo.net/ground_gnuradio_ota.html On Wed, 13 Feb 2008, kuba jamro wrote: Hi all, I was wondering if anyone knows of a location (HTTP, FTP or torrent) where I can get some real-world sample data (i.e. a few seconds worth of the FM, VHF or UHF band). I don't have the required SDR hardware yet and I'd like to get started on working out some of the theory using Octave first before I do. Regards, Kuba. ___ 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
Re: [Discuss-gnuradio] OFDM Updates
Shravan Rayanchu wrote: Hi Dan and Tom, Thanks for your comments. I'll trying changing the parameters and look at the log files to see what might be wrong. Shravan As you will see in my original email, the problem is inside of the OFDM receiver, and I pointed out what that issue is and how to see it. Changing the parameters externally will do nothing to solve this. Tom On Feb 13, 2008 6:15 PM, Tom Rondeau [EMAIL PROTECTED] wrote: Dan Halperin wrote: Shravan Rayanchu wrote: Basically, I seem to completely lose some of the packets in the air. Of the packets I receive, almost all the packets are received correctly. Initially, the error rate was too high (The packets were getting lost and also among the packets received, lot of them were in errors), so I increased tx-amplitude to ~3000. Am I using the right version of the code ? Is the tarball release better to use ? Can you please let me know if there are any parameters which I need to change ? Tom mentioned an existing problem in the email you replied to, which you didn't address in your response. Could that be the problem or have you ruled it out? Yes, thanks for pointing that out, Dan. The problem I discussed in my original email is certainly the problem; it's exactly what I was seeing. For debugging these types of errors, I really do suggest (from experience!) that you start saving the outputs of the intermediate stages to disk and seeing what they look like. It might require some understanding of the receiver, but then again you probably want that knowledge anyway... Excellent point. Visualization tools are a key to understanding and debugging this stuff. By using the --log option, the receiver will dump output data files for every important (and even some not-so-important) block in the chain. The gr_plot_XXX.py scripts are useful for getting a quick look at the output. There is a local gr_plot_ofdm.py script distributed as part of the ofdm example directory that provides a specific way of looking at the output of the OFDM system. It's likely (as I found with older versions of the DBPSK code, for instance) that some of the synchronization and/or timing algorithms aren't working in your setup. But maybe there's lots of cochannel interference. Maybe the RSSI is low. Maybe the frequency offset of your daughterboards is too large to be handled by the PLLs... Always the case, really. These methods are as straight-forward as we can make them to do the basic receivers for different modulations. Most standard/commercial digital radios do a whole lot more to make sure the signal is properly received. Cochannel interference will quickly kill these implementations. And in the case of the M-PSK code, my first version was textbook while the second version was the right way; that helps, too :) Tom ___ 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] Reading registers on the USRP
I've read that post before. It more or less gave me reassurances on what I had gathered that had to be done to implement a simple in-line multiplier in the TX chain. The post tells me what registers are readback, but not how to read them back. When I came across the post originally, it pointed me in the right direction to where I should connect the output of my new module. -Kevin [EMAIL PROTECTED] wrote: Hi, I'm having a little trouble reading the readback registers that are on the USRP. I know that most registers are write only with their contents mirrored on the computer. The reason I want read those registers back is because of a custom unit I am testing. I currently load a custom implementation on the USRP that consists of 1 TX chain and 2 custom units, one of which feeds back information into the unused readback ports (rssi0 to rssi3). I'm able to read from the capabilities register using '_read_fpga_register(FR_RB_CAPS)' and it returns a value that makes sense. When I try reading from any other register, the value returned is consistently '0'. I'm reading the registers in a loop in case the value changes after a given amount of time. I'm not sure what to try next, can someone give me a new direction? -Kevin This post might help: http://lists.gnu.org/archive/html/discuss-gnuradio/2007-05/msg00356.html -Roshan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Reading from TVRX board
Thank you for the reply. That is the script I use for reading in the data into MATLAB. I should have made that more clear. On Thu, Feb 14, 2008 at 1:55 PM, Johnathan Corgan [EMAIL PROTECTED] wrote: On 2/14/08, Jonathon Pendlum [EMAIL PROTECTED] wrote: Then, I use a script written to convert the binary data file into a MATLAB vector. The data format is alternating I and Q single-precision floating point in whatever endianness your computer is. See the following for how to read into MATLAB: http://gnuradio.org/trac/browser/gnuradio/branches/releases/3.1/gnuradio-core/src/utils/read_complex_binary.m -- Johnathan Corgan Corgan Enterprises LLC http://corganenterprises.com/ ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Reading from TVRX board
Hello, I'm a student trying to use the USRP with the TVRX board to do a simple FM stereo receiver. I previously wrote a MATLAB model of a FM transmitter and receiver, and I wanted to use real data in my model. I've been modifying the wideband fm example to record data from the TVRX board by basically inserting some of the l1_record.py code like this: self.dst = gr.file_sink(gr.sizeof_gr_complex, 'data.txt') self.head = gr.head(gr.sizeof_gr_complex, 80) self.connect(self.u, self.head, self.dst) Then, I use a script written to convert the binary data file into a MATLAB vector. However, the recorded data is not meaningful to me. When plotting the data, instead of seeing some kind of waveform, I see what looks similar to a NRZI waveform. If you wish to see what I am seeing, here is a screenshot of the data: http://web.ics.purdue.edu/~jpendlum/usrpdata.bmp It is also important to note that the example wideband FM code runs flawlessly. I can tune to local radio stations and listen to them. These are the questions that I've tried very hard to answer, but I can't seem to figure out: 2. Is the recorded data in some kind of encoded format, and if so, what is this format? 3. If not, then what am I doing incorrectly in my record script? If anyone could help, I would greatly appreciate it. Thanks. Jon Pendlum ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Reading from TVRX board
On 2/14/08, Jonathon Pendlum [EMAIL PROTECTED] wrote: Then, I use a script written to convert the binary data file into a MATLAB vector. The data format is alternating I and Q single-precision floating point in whatever endianness your computer is. See the following for how to read into MATLAB: http://gnuradio.org/trac/browser/gnuradio/branches/releases/3.1/gnuradio-core/src/utils/read_complex_binary.m -- Johnathan Corgan Corgan Enterprises LLC http://corganenterprises.com/ ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] gnuradio block for boolean operations
Hello all, I want to perform some simple boolean operations on a stream of data. For example invert the bits from the output of the demodulators or convert from NRZ to NRZI I was thinking something like 1) gr_xor_bb, gr_and_bb, gr_or_bb, br_not_bb ... or 2) maybe gr_boolean(xor) , gr_boolean(and) ... Is this something someone has started? Is there another way I should go about this? If this is something that should be done can someone give me an idea of the desired format (1 or 2 or something else) Tim ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Any working transmitter/receiver package?
Hello folks, I want to try some working transmitter and receiver GSR package. It seems most emails in the archive are talking about receiving while I'm interested in both transmitting and receiving. I prefer to have a system with a bandwidth of 8 MHz, but I'm willing to settle for 6 MHz if it is the best the current USRP can do. I have tried the BBN package and want to try something else. Any suggestion is welcome! Thanks, Junxing ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] How to use the TV board?
Hello Everyone - I am doing my best to understand how the TVRx board works. I have Rev. 3 of the TV board, with MicroTuner module with IF of ~44 MHz. (Preface - Thanks for your patience, as I am relatively new to GNU radio and the USRP!) In my experiment, I have an 80 MHz sine wave at 2 mV pk-pk input to the TV tuner from a function generator. The goal is to properly record this signal to a data file, then plot the time domain and FFT of the signal in Matlab to verify functionality. My record script is from the examples directory: #!/usr/bin/env python Read a specified number of samples from a USRP and write the data to a file. from gnuradio import gr, eng_notation from gnuradio import usrp import sys class record_graph(gr.flow_graph): def __init__(self): gr.flow_graph.__init__(self) self.u = usrp.source_c(which=0, decim_rate=8) self.dst = gr.file_sink(gr.sizeof_gr_complex, 'recorded.dat') self.head = gr.head(gr.sizeof_gr_complex, 5000) self.connect(self.u, self.head, self.dst) self.u.set_mux(usrp.determine_rx_mux_value(self.u, [1,0])) self.subdev = usrp.selected_subdev(self.u, [1,0]) self.subdev.set_gain(10) tuning = self.u.tune(0, self.subdev, 7900) print baseband_freq:, tuning.baseband_freq print dxc_freq:, tuning.dxc_freq print residual_freq:, tuning.residual_freq print inverted:, tuning.inverted fs = self.u.converter_rate() print source converter rate:, fs try: record_graph().run() except KeyboardInterrupt: pass Now, as I understand it, with my tuning target frequency in this code at 79 MHz and a decimation rate of 16, and 64 MS/s sampling, then the sine wave signal should appear at approximately a 1 MHz frequency. However, all I am seeing is wideband noise. Does anybody know why this may be? Also, what can you tell me about using the TV board? -- Posted via http://www.ruby-forum.com/. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP and gnuradio errors - seems to disconnect often
I've been doing some testing with a new USRP (manufactured 12/2007). My configuration is an Intel USB interface on a P965-S motherboard. I dual-boot XP SP2 and Arch Linux. In XP I've used Cygwin and MinGW. I've tried removing all but the TVRX board (which is mainly what I'm attempting to test), and my problems persist. I've also switched to another USB cable just to be sure. What seems to be happening, is at random intervals while running the test scripts (mainly usrp_wfm_rcv.py and usrp_tv_rcv), the GUI hangs, and when I exit the GUI, I get messages as follow: uOuOuOuOuOuOread: usb_reap_async: usb_reap_async: error: A device attached to the system is not functioning. usb_control_msg failed: error sending control message: win error: The device does not recognize the command. usb_control_msg failed: error sending control message: win error: The device does not recognize the command usrp_basic_rx: set_fpga_rx_enable failed usb_control_msg failed: error sending control message: win error: The device does not recognize the command. usb_control_msg failed: error sending control message: win error: The device does not recognize the command. usrp_basic_rx: failed to fini AD9862 RX regs I've tried using two versions of usblib (0.1.10.1 and 0.1.12.1), and even tried loading different firmware. The result is always the same. It also does not matter which environment I'm using, Cygwin, MinGW, or Linux; the result is the same. The other board I've tried using is the FLEX900 -- same results with its scripts. I'm left to assume that I have faulty hardware, but I'm wondering if I'm the only one who is experiencing such problems. Any ideas? Anyone? I've followed the wiki instructions exactly. Oh, another symptom (or is it?)... tuning in NTSC, not so good. I can see the image but it doesn't sync properly-- I find myself wanting to look for a those little knobs on the side of old TVs, you know the ones that sync up the image vertically and horizontally. Tuning in FM audio sounds fine. It could be my signal is weak, but somehow I doubt it. Any advise would be appreciated. -Casey _ Shed those extra pounds with MSN and The Biggest Loser! http://biggestloser.msn.com/___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Cannot Change USRP Interpolation Rate Dynamically
Hi, It seems that there is a bug in gnuradio 3.1.1 (and up to today latest truck revision) in the USRP rbf standard file. When trying to change the interpolation rate dynamically, the output get distorted badly even if the program restore the started interpolation value. I have an old gnuradio 3.0.3 (Revision 6082) which does not have this problem at all. Checked with two RFX2400 boards, the same problem (it is an FPGA Problem). To check this , start the test (for example) with interpolation rate 128 and change it dynamically to 16 (it will be badly distorted). Now, try to restore it back to 128, and you will see that it stacked at the 16 with distorted waveform. Best Regards, Firas -- View this message in context: http://www.nabble.com/Cannot-Change-USRP-Interpolation-Rate-Dynamically-tp15495473p15495473.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
