Re: [Discuss-gnuradio] Simple FM receiver GRC error
That was the error I was getting. I've found that I still get it if I do not start gnuradio-companion in the directory where simple_fm_helper is located. Apparently, that Import block/function is very simplistic and will only import from the directory that companion was started in. -- 73s jim KI6NJF No. If the helper .py file has been copied into $HOME/bin (which gets done by the makefile), *AND* PYTHONPATH includes $HOME/bin you should be golden. Use the starter shell script, which should also be in $HOME/bin: simple_fm_rcv -- Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Data rate of a TCP source
Hi, Does Gnuradio provide a possibility to measure a net data rate of a TCP source? I would like to output how many packets (or bits) per second are being successfully received in my top_block. Thanks Piotr ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] output signal amplifier on USRP?
Hi, We are using USRP1 to build a RFID reader which operates on 915MHz frequency. The RF daughterboard used is RFX 900. Currently the power issued by the daughterboard is too small, only 200mW. Can we increase the output power by connecting daughterboard with a signal amplifier? We want to increase the output power because it can give us longer tag inventory ranges. Thanks very much for your suggestions. Pengyu Zhang ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Recording continuous I-Q stream and frequency offset with an external reference clock
Hi Tom Nick, Thanks for your replies. The function generator is producing a sine wave with 1 V (10 MHz). This is going to the ref clocks. The E light is ON and I have changed the clock source option to be external in gnuradio-companion environment. I tried with square wave, too. But the output did not change. The transmission is taking place at 450 MHz carrier frequency. I am using USRP2's with RFX400 FLEX400 daughterboard. In fact, I see a 6 kHz frequency offset even without the reference clock. Does it suggest that the external reference clock is somehow not going through? I don't know if I should change more options in gnuradio-companion toolbox to make the reference clock work. Thanks, Nazmul On Thu, Jun 7, 2012 at 11:31 PM, Nick Foster n...@ettus.com wrote: On Thu, Jun 7, 2012 at 7:11 PM, Tom Rondeau t...@trondeau.com wrote: On Thu, Jun 7, 2012 at 1:30 PM, Nazmul Islam mnis...@winlab.rutgers.edu wrote: I got a partial answer to my previously posted question :). When I pass the complex baseband I Q with a costas loop block, the output indeed looks like a square wave. Does it mean that external reference clock does not correct the phase/carrier offset error? Does it only solve the timing error issue? Thanks, Nazmul Glad that you are able to get far enough to recover it. As for the remaining 6 kHz offset, what's the RF frequency? What does 6 kHz translate into for a parts per million? While I would expect them to be the same with both locked to the same external clock, we are talking about reality here, so things aren't always that cooperative. I can't think what would cause this kind of an offset, though, as it seems rather large. Maybe someone with more hands-on hardware experience with precision equipment can jump in here. Tom 6kHz is way too high. They should be cycle-locked. What is the amplitude of the clock signal you're feeding into the USRP2? --n On Thu, Jun 7, 2012 at 12:00 PM, Nazmul Islam mnis...@winlab.rutgers.edu wrote: Hi Tom, First of all, thanks a lot for your detailed reply. I appreciate it. I did as you told in the last email, i.e., I transmitted a square wave (switching between 0.5 to -0.5). The sqaure wave's period was 1 ms and the sampling rate was 1 MHz. I have attached the real part of the outputs with the email. The output shows a phase shift after every 500 samples, i.e., half period of the square wave with 1 MHz sampling rate. The sinusoidal nature of the output probably comes from frequency offset of the two USRP's. I expected this for an internal clock source. However, I see a 6 kHz frequency offset (3 sine period per 0.5 ms) even with the presence of an external clock. The external clock is driving both USRP's. The E LED is on. I am using a sine wave with 10 MHz frequency 7 dBm amplitude as the external clock. I also put the clock source options in grc as external. Do I need to make any other changes in the GRC blocks to inform USRP about the external source? Any suggestions will be appreciated. Thanks for all of your help. Nazmul On Fri, May 25, 2012 at 1:40 PM, Tom Rondeau t...@trondeau.com wrote: On Thu, May 24, 2012 at 7:07 PM, Nazmul Islam mnis...@winlab.rutgers.edu wrote: Hello, I want to transmit a continuous stream of 1's or 0's (with bpsk modulation) and record the received I-Q stream. I am trying to use the 'digital_bert_tx.py' code for transmission and the uhd_rx_cfile code (gr-uhd/apps) for reception. Thereafter, I use the read_complex_binary code to read the data in Matlab. Surprisingly, I am receiving similar type of I-Q stream (around 0.3 + j 0.3) for both 1 and 0 transmission. I am using the following commands: self._bits = gr.vector_source_b([1,], True) (I either transmit infinite 1 or infinit 0's. When I transmit infinite 0's, I replace '1' by '0' in the command) ./digital_bert_naz_tx.py -r 5M -m bpsk -f 450M --gain 0.1 --non-differential(I am using non-differential since I want to see the different amplitude levels for '1's or 0's) ./uhd_rx_cfile -N 1000 -f 450M --samp-rate 5M file.dat (Since I am using bpsk, sample-rate should be equal to bit rate, I assume) Ideally, the I-Q stream of bpsk should show 180 degree phase shift for 1 and 0 transmission. I am getting the same value for both transmission. Can anyone suggest where I am making mistakes? Thanks, Nazmul Nazmul, Hard to say from this info. A few things to note on, though. First, 1000 samples isn't that much. There are startup transients in hardware, so you might just be seeing effects of those. I'd capture ten thousand or a million and just read out the last 1000. Also, the transmitter and receiver are running on two different clocks, so their frequency and phases aren't going to match, unless
Re: [Discuss-gnuradio] Recording continuous I-Q stream and frequency offset with an external reference clock
On Fri, Jun 8, 2012 at 8:57 AM, Nazmul Islam mnis...@winlab.rutgers.eduwrote: Thanks for your replies. The function generator is producing a sine wave with 1 V (10 MHz). This is going to the ref clocks. It's possible that a function generator output, when loaded down by two REF inputs in parallel, might not produce the amplitude necessary to reliably work, nor might it have the necessary rise time. You'll need to measure these to ensure they meet the REF in requirements. The symptoms you are seeing are an indication they do not. Johnathan ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Gnuradio Screencast for Absolute Beginners
Hi Community , some more video are up !! I have shown how to start working with gnuradio-companion. There are 4 screen casts. Very introductory for the new comers :) connecting the blocks, data types, putting multiple windows in tabs, etc I have shown. Suggestions and feedbacks are very welcome. Please suggest me some good(free) screencast tools. Right now I am using gtk-recordmydesktop which gives me .ogv file and youtube creates much pain with .ogv format. Also this screen cast is very unorganized. from next screen casts I will try to organize them point wise :) Here are the links : http://www.youtube.com/watch?v=pWHlK-Kcn9Mfeature=plcp http://www.youtube.com/watch?v=hkfbousBchEfeature=plcp http://www.youtube.com/watch?v=bp9b0ozsboIfeature=plcp http://www.youtube.com/watch?v=j9A-5MzZyt0feature=plcp More videos will be up soon :working: sumitstop wrote: Hi Community , some more video are up 1.In system transmission and reception using digital benchmark and ofdm benchmark files. 2. Complete instructions on how to install UHD(latest ver), gnuradio (latest ver) and gnuradio-companion from source code(for those ppl who enjoy building by themselves) :-)) ** instructions on setting python path as well as library path also shown. ~~ I also wanted to make some videos on getting started with hardware on gnuradio but unfortunately my shipment from ettus research worth $9K got stuck. its showing Clearance delay - Import :,( Anyways I will use my existing usrp2/1 to make the videos in the coming days ~~ More videos will be up very soon :working: sumitstop wrote: Yes Tom I will be glad to contribute in some or other way for the gnuradio :-) Tom Rondeau-2 wrote: On Mon, Apr 9, 2012 at 4:42 PM, sumitstop sumit.ku...@research.iiit.ac.in wrote: Hi Community, Just uploaded 11 more screen casts in GNURADIO for absolute beginners. They are mostly related to using benchmark files of digital transmission and ofdm transmission. Some playing with the spectrum sensing code is also there. I have increased the font size as well as bright back ground for better visibility. http://www.youtube.com/user/2011HPS?feature=watch A lot more will be coming. Cheers :working: Thanks for putting these up and sharing with everyone! Tom heckpiet wrote: thx mate !! Cheers Piet Am 8. April 2012 01:07 schrieb sumitstop sumit.ku...@research.iiit.ac.in: Hi Community, I have uploaded screencast of some very basic things for the beginners in gnuradio like installing gnuradio, finding common examples of usrp, uhd, utilities etc. Also getting information about usrp's / daughterboards, antennas, burning SD card etc. Here is the link http://www.youtube.com/user/2011HPS?feature=watch http://www.youtube.com/user/2011HPS?feature=watch Although these things are given in enough detail on gnuradio webpage but I think watching on screen will be very helpful for the starters :) Enjoy :) ** Suggestions/improvements are most welcome - Sumit Kr. Research Assistant Communication Research center IIIT Hyderabad India -- View this message in context: http://old.nabble.com/Gnuradio-Screencast-for-Absolute-Beginners-tp33650161p33650161.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio - Sumit Kr. Research Assistant Communication Research center IIIT Hyderabad India -- View this message in context: http://old.nabble.com/Gnuradio-Screencast-for-Absolute-Beginners-tp33650161p33657814.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio - Sumit Kr. Research Assistant Communication Research center IIIT Hyderabad India -- View this message in context: http://old.nabble.com/Gnuradio-Screencast-for-Absolute-Beginners-tp33650161p33983007.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Deleting a block in C++
Greetings, Is there a smart way to delete a GNU Radio block in C++? Until now I have been using the shared_ptr().reset() method but it seems to me that it will only call the destructor if the parent top_block has not been run. This gives me problems when I try to delete and recreate a hardware input block (e.g. gr-audio input) where the new device can be the same as the old one, in which case it will report device busy. The specific code in question is here: https://github.com/csete/gqrx/blob/afd02e241f0569e485ecbb1c312599ba60c5431c/applications/gqrx/receiver.cpp#L112 It makes no difference if I stop() the top block before attempting the reset(). Perhaps these hardware input blocks are coded incorrectly and should close the device in their stop() method? Or is there something else we can do? Thanks in advance Alex ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP1 XCV2450 LO - can it be bypassed with the motherboard's LO
Google is your friend: http://code.ettus.com/redmine/ettus/projects/public/documents On Jun 8, 2012, at 2:12 PM, Nick Iliev wrote: Hello, we have a USRP1 with 2 XCVR2450 daughtercards. Each XCVR2450 has its own LO however , we would like to bypass it with the motherboard's X-TAL source. Both XCVR2450 daughtercards will then be driven synchronously by the motherboard. Is this possible ? If so, is there a schematic of the XCVR2450 and motherboard which will show the required jumpers and/or SMTs ? If not, which USRP (2 ? ) and daughtercards do we need ? Thank you, Nick and Han UIC wireless lab ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP1 XCV2450 LO - can it be bypassed with the motherboard's LO
Each XCVR2450 is already locked to the motherboard crystal. But bypass it with the motherboard's X-TAL source does not make sense. The LO is generated by locking to the motherboard crystal source. No bypassing is necessary. Matt On Fri, Jun 8, 2012 at 2:12 PM, Nick Iliev nilie...@gmail.com wrote: Hello, we have a USRP1 with 2 XCVR2450 daughtercards. Each XCVR2450 has its own LO however , we would like to bypass it with the motherboard's X-TAL source. Both XCVR2450 daughtercards will then be driven synchronously by the motherboard. Is this possible ? If so, is there a schematic of the XCVR2450 and motherboard which will show the required jumpers and/or SMTs ? If not, which USRP (2 ? ) and daughtercards do we need ? Thank you, Nick and Han UIC wireless lab ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] gr-trellis convolutional coder FSM
Hi, I'm working on a modulator using a punctured (non-recursive) convolutional coder based on a 1/2 rate mother code with length 7. However I find the documentation of gr-trellis pretty hard to read, I don't really understand how punctuation should actually be implemented. Are there any additional documents or papers on designing the FSM of a convolutional coder? Thanks, Clemens ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] question about print out of overrun and under run indication
Hi, I have a couple of questions about the print out of the overrun and underun indications. Is it possible to turn off the output of those indications? And second is gnuradio doing anything with stdout that would affect redirecting stdout? This is the text output I normally see in a shell window. (I don't see the - lines that just to separate the text) --- -- USRP-B100 clock control: 10 -- r_counter: 2 -- a_counter: 0 -- b_counter: 20 -- prescaler: 8 -- vco_divider: 5 -- chan_divider: 5 -- vco_rate: 1600.00MHz -- chan_rate: 320.00MHz -- out_rate: 64.00MHz -- UHD Warning: Unable to set the thread priority. Performance may be negatively affected. Please see the general application notes in the manual for instructions. EnvironmentError: OSError: error in pthread_setschedparam UHD Warning: The hardware does not support the requested RX sample rate: Target sample rate: 2.50 MSps Actual sample rate: 2.461538 MSps gr_fir_ccc: using SSE gr_fir_fff: using SSE Using Volk machine: sse4_1_64_orc In my application I redirect stdout to a different buffer. Which works at first. I get the following redirected to my buffer -- USRP-B100 clock control: 10 -- r_counter: 2 -- a_counter: 0 -- b_counter: 20 -- prescaler: 8 -- vco_divider: 5 -- chan_divider: 5 -- vco_rate: 1600.00MHz -- chan_rate: 320.00MHz -- out_rate: 64.00MHz -- after that nothing is redirected and everything goes back to being output in the shell window. I'm not an expert on redirecting stdout but is there anything in gnuradio that would make that stop working? stephen ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Simple FM receiver - one last question
Thank you for reading this. I have one last error to overcome: Error 0: Block - gr_freq_xlating_fir_filter_xxx_0 - Frequency Xlating FIR Filter(gr_freq_xlating_fir_filter_xxx): Sink - in(0): Port is not connected. Can anyone offer a suggestion that will sort this out? -- Regards, Phil ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
