Re: [Discuss-gnuradio] bug in wfm_rcv_pll and fix, who has stereo FM specs/info and noise and gain issues
Martin Dvh wrote: > Hi, > I found a nasty bug in the wfm_rcv_pll.py code. > > The pilot tone pll should return the recovered carrier, > For this you should use gr.pll_refout_cc, not gr.pll_carriertracking_cc. > pll_carriertracking returns the input transformed to baseband using the > recovered carrier. > pll_refout returns the recovered carrier. > Great catch, Martin. > With the fixed code I now actually get stereo. > (Before you would get a kind of attenuated, distorted, spectrum inverted > stereo) > Can you check it in? > I tested it with a stereo-coder I wrote in gnuradio, and now I seem to > actually get stereo seperation. > (stereo modulater is attached) > > But now I do get a lot of noise when decoding stereo. > > I also don't quite understand why double side band suppressed carrier > Left-Right audio is attenuated and needs a factor 20 for gain. > (It seems to be correct or at least close) > I would try this with the regular (non-PLL) FM demod. I think the rolloff of the PLL tracking loop is what is giving you the lower gain. > The code comments say 10 dB > The actual code uses a factor 20 which corresponds to 20 *log10(20)= 26 dB. > This 26 dB seems to be quite accurate, but where is this number based on? > > can you give me a link to more info or the stereo FM specs on this. > > # Pick off the double side band suppressed carrier Left-Right > audio. It is attenuated 10 dB so apply 10 dB gain > > stereo_dsbsc_filter_coeffs = gr.firdes.complex_band_pass(20.0, > > > Greetings, > Martin > > fix for wrong pll is below: > --- gnuradio-core/src/python/gnuradio/blksimpl/wfm_rcv_pll.py 2007-06-11 > 18:12:55.0 +0200 > +++ gnuradio-core/src/python/gnuradio/blksimpl/wfm_rcv_pll_fixed.py > 2007-06-17 08:07:43.0 +0200 > @@ -131,8 +131,8 @@ > max_freq = -2.0*math.pi*18990/audio_rate; > min_freq = -2.0*math.pi*19010/audio_rate; > > -self.stereo_carrier_pll_recovery = > gr.pll_carriertracking_cc(alpha,beta,max_freq,min_freq); > -self.stereo_carrier_pll_recovery.squelch_enable(False); > +self.stereo_carrier_pll_recovery = > gr.pll_refout_cc(alpha,beta,max_freq,min_freq); > +#self.stereo_carrier_pll_recovery.squelch_enable(False) > #pll_refout does not have squelch yet, so disabled for now > > > # set up mixer (multiplier) to get the L-R signal at baseband > > > > > > ___ > 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] phase synchronization
micael magpayo wrote: > How does one determine the initial phase for the cordic unit (cordic.v)? It is 0 at reset. > and is there a dpll implemented for the usrp_standard build? (If there > is, I can't find it) No. We typically do that on the host in software. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] FLEX400
> (2) Set PLL frequency of RFX400 > > I am using RFX400 for receiving. It works fine. > But I would like to set PLL (the local oscillator > on the board) to a certain frequency. Please show > me how to control frequency of the PLL on the board. > Use the normal set_freq method as in usrp_siggen.py. If you need to control it yourself, see how it is done in gr-usrp/src/db_flexrf.py Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Different frequencies for TX/RX and RX2 port on RFX2400
Tarun Tiwari wrote: > Hi, > > I was just wondering if someone can give me little bit of information > about the clocks for TX/RX & RX2 antenna port on RFX2400. > > My questions are related to simultaneous transmission using TX/RX and > reception using RX2, so my transmit and receive frequencies have to be > different on the transciever board ( please correct if I am wrong). > So, I need to know some basics of RFX2400 antenna port operation. > > Do we have different frequency generator circuits for these two ports > or single circuit used for both? There are separate VCOs and PLLs for TX and RX. > Now when I read the mail from Matt ( > http://lists.gnu.org/archive/html/discuss-gnuradio/2005-07/msg00035.html > ), what I see that there is a clock line difference of around 1 cm. > So, if I have two different frequency generator circuits for TX/RX & > RX2 ports, then do we still get this clock line difference? (by > chance, I am not a microelectronics guy and so, I dont understand the > meaning of clock line difference and its effect, therefore, I would > like to know about it in brief) You don't need to care about that. > > Or, if we have only one frequency generator circuit then can we > control the different frequencies on these two antenna ports > simultaneously? If yes, then can you please refere me some > documents/codes/examples, so that I can understand the use of it? If > not, then is it done in sequential manner or some priority based > scheduling? > > Any help would be gratefully accepted. > > Thanks in advance. > > Regards, > Tarun > UT Dallas > > > ___ > 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] Basic RX daughterboard: DC bias
Chris Stankevitz wrote: > Hi, > > When I run the basic RX daughterboard with no input cable attached, > usrp_fft reports a signal at 0 Hz (which I assume to be some kind of > DC bias created within the USRP or daughterboard). How can I remove > this? Take a long term average of the signal and subtract it from the signal. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP fails after successful test
Ian Larsen wrote: > Hello, > > I'm trying to figure out what's going on here. I have a USRP that > works just fine when tested with the test_usrp_standard_rx test > program, but subsequent runs of that fail with the error: > > usrp: failed to find usrp[0] > die: lt-test_usrp_standard_rx: usrp_standard_rx::make > > If I unplug the power from the USRP and run the program again, it's > successful, but then I get the same error after that. I'm running > this on Fedora 7 and have tried versions 3.0.2 and 3.0.3 of gnuradio. > Also tried this on FreeBSD with this same computer, same problem. > > I have another computer with Fedora Core 6 on it, gnuradio 3.0.2, and > it works fine. > > Any ideas? Have any of the libraries, like libusb, changed since then > or introduced bugs? I believe this is because you have the new kernel in F7. You need to get the latest SVN version of gnuradio Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] USRP fails after successful test
Can you give us the output of dmesg? It might give us some insight in to an error thats occurring. - George Ian Larsen wrote: Hello, I'm trying to figure out what's going on here. I have a USRP that works just fine when tested with the test_usrp_standard_rx test program, but subsequent runs of that fail with the error: usrp: failed to find usrp[0] die: lt-test_usrp_standard_rx: usrp_standard_rx::make If I unplug the power from the USRP and run the program again, it's successful, but then I get the same error after that. I'm running this on Fedora 7 and have tried versions 3.0.2 and 3.0.3 of gnuradio. Also tried this on FreeBSD with this same computer, same problem. I have another computer with Fedora Core 6 on it, gnuradio 3.0.2, and it works fine. Any ideas? Have any of the libraries, like libusb, changed since then or introduced bugs? -Ian Larsen ___ 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] USRP fails after successful test
Hello, I'm trying to figure out what's going on here. I have a USRP that works just fine when tested with the test_usrp_standard_rx test program, but subsequent runs of that fail with the error: usrp: failed to find usrp[0] die: lt-test_usrp_standard_rx: usrp_standard_rx::make If I unplug the power from the USRP and run the program again, it's successful, but then I get the same error after that. I'm running this on Fedora 7 and have tried versions 3.0.2 and 3.0.3 of gnuradio. Also tried this on FreeBSD with this same computer, same problem. I have another computer with Fedora Core 6 on it, gnuradio 3.0.2, and it works fine. Any ideas? Have any of the libraries, like libusb, changed since then or introduced bugs? -Ian Larsen ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Error in my first USRP test
Hi I installed fresh version of Cygwin. I followed the steps again I think I installed wrong version of some packets, now I have it working but I can not run test_counting.py . --Alaelddin George Nychis wrote: just to take a step back... were you able to solve the make check problem you sent to the board earlier? - George Alaelddin Mohammed wrote: Hi I tried to run test_counting.py , I got the folloing message $ python test_counting.py usb_control_msg failed: usb_control_msg: sending control message failed, win err or: A device attached to the system is not functioning. usb_control_msg failed: usb_control_msg: sending control message failed, win err or: A device attached to the system is not functioning. gr_check_counting: enter_SEARCHING at offset0 (0x) gr_check_counting: expected 0 (0x) got 2 (0x0002) offset0 (0x) gr_check_counting: expected 3 (0x0003) got 3 (0x0003) offset1 (0x0001) gr_check_counting: expected 4 (0x0004) got 4 (0x0004) offset2 (0x0002) gr_check_counting: expected 5 (0x0005) got 5 (0x0005) offset3 (0x0003) gr_check_counting: enter_LOCKED at offset3 (0x0003) Could you please what is wrong --Alaelddin ___ 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] Error in my first USRP test
just to take a step back... were you able to solve the make check problem you sent to the board earlier? - George Alaelddin Mohammed wrote: Hi I tried to run test_counting.py , I got the folloing message $ python test_counting.py usb_control_msg failed: usb_control_msg: sending control message failed, win err or: A device attached to the system is not functioning. usb_control_msg failed: usb_control_msg: sending control message failed, win err or: A device attached to the system is not functioning. gr_check_counting: enter_SEARCHING at offset0 (0x) gr_check_counting: expected 0 (0x) got 2 (0x0002) offset0 (0x) gr_check_counting: expected 3 (0x0003) got 3 (0x0003) offset1 (0x0001) gr_check_counting: expected 4 (0x0004) got 4 (0x0004) offset2 (0x0002) gr_check_counting: expected 5 (0x0005) got 5 (0x0005) offset3 (0x0003) gr_check_counting: enter_LOCKED at offset3 (0x0003) Could you please what is wrong --Alaelddin ___ 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] Error in my first USRP test
Hi I tried to run test_counting.py , I got the folloing message $ python test_counting.py usb_control_msg failed: usb_control_msg: sending control message failed, win err or: A device attached to the system is not functioning. usb_control_msg failed: usb_control_msg: sending control message failed, win err or: A device attached to the system is not functioning. gr_check_counting: enter_SEARCHING at offset0 (0x) gr_check_counting: expected 0 (0x) got 2 (0x0002) offset0 (0x) gr_check_counting: expected 3 (0x0003) got 3 (0x0003) offset1 (0x0001) gr_check_counting: expected 4 (0x0004) got 4 (0x0004) offset2 (0x0002) gr_check_counting: expected 5 (0x0005) got 5 (0x0005) offset3 (0x0003) gr_check_counting: enter_LOCKED at offset3 (0x0003) Could you please what is wrong --Alaelddin ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] RE: [gsm] GMSK: GSM initial phase for a burst
Is there an initial condition to the differential encoder? Seems odd that they wouldn't just send the 148 pi/2 phase shifts. -Clark From: "Jeffrey Karrels" <[EMAIL PROTECTED]> Reply-To: [EMAIL PROTECTED] To: [EMAIL PROTECTED], discuss-gnuradio@gnu.org Subject: [gsm] GMSK: GSM initial phase for a burst Date: Mon, 18 Jun 2007 14:09:46 -0400 Hello everyone. I am looking at the frequency correction burst of a GSM signal. According to spec the original data defines 148 bits of 0 that are differentially encoded and GMSK modulated. After the data goes through the differential encoder it ends up as [-1,1,1, (142 1s), 1,1,1]. I have taken this burst and plotted I vs Q (which is attached). I was expecting to see the amplitude ramp up followed by a negative pi/2 phase shift, followed by 147 positive pi/2 phase shifts, and a ramp down. I never see the initial negative phase shift though. Am I missing something in my sanity? Any thoughts or ideas? Thank you for your time Jeff << fcch2.png >> _ Get a preview of Live Earth, the hottest event this summer - only on MSN http://liveearth.msn.com?source=msntaglineliveearthhm ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Parameters for USRP (motherboard only) FM receiver
On 6/19/07, Tarun Tiwari <[EMAIL PROTECTED]> wrote: Hi Shane, On 6/19/07, Shane Clark <[EMAIL PROTECTED]> wrote: > Hi, > > I'm trying to setup the USRP to receive and demodulate an FM signal at > 175kHz. I have based my code on the wfm_rcv... examples, but I always > get a "no suitable daughterboard found" error. I do not understand all > of the parameters that I am setting on the USRP so I was wondering if > anyone could explain them or point me to a resource on this. Which daughterboard are you using? > Basically, I know that I want the frequency to be 175kHz and I have > gotten this to work with transmission, so I assume that's valid. I am > more or less lost on decimation, interpolation etc. > > Any help is appreciated. > > -Shane ~Tarun > ___ I am using the DBSRX board. I have actually gotten the receiver working more or less through trial and error, but I have yet to do the FM demodulation in Python. I put something together in GRC that uses USRP -> NBFM receive -> file_sink, but I just accepted the default values as I do not understand the meaning of the NBFM block's parameters. -Shane ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Parameters for USRP (motherboard only) FM receiver
Hi Shane, On 6/19/07, Shane Clark <[EMAIL PROTECTED]> wrote: Hi, I'm trying to setup the USRP to receive and demodulate an FM signal at 175kHz. I have based my code on the wfm_rcv... examples, but I always get a "no suitable daughterboard found" error. I do not understand all of the parameters that I am setting on the USRP so I was wondering if anyone could explain them or point me to a resource on this. Which daughterboard are you using? Basically, I know that I want the frequency to be 175kHz and I have gotten this to work with transmission, so I assume that's valid. I am more or less lost on decimation, interpolation etc. Any help is appreciated. -Shane ~Tarun ___ 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] FLEX400
Dear Sirs, I have two questions on USRP and GNU radio use. (1) Change of output file of file_sink I would like to record data into files. I am now using file_sink in the flow graph. Now my program is very simple and it can record data into one file only. I want to change the program that it can start/stop receiving, and for different runs, record data into different files. How can I change output file (= filename)? Do I need to stop the program and return to OS for each file output? (2) Set PLL frequency of RFX400 I am using RFX400 for receiving. It works fine. But I would like to set PLL (the local oscillator on the board) to a certain frequency. Please show me how to control frequency of the PLL on the board. Thank you very much for your help. Regards, Mamoru Yamamoto [EMAIL PROTECTED] ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] noise problem with USRP
Chris- thanks for the suggestions. I may try to add the ferrite toroid. It's just curious that I didn't notice this before. Maybe my power brick is functioning differently, although it is brand new. thanks, eric On Mon, 18 Jun 2007, Chris Albertson wrote: --- [EMAIL PROTECTED] wrote: I'm seeing a strange noise issue with my USRP. I have a simple antenna fashioned out of a spool of wire connected to a LF-DC daughterboard So if (1) antenna is connected and (2) you are using notebook connected to mains then you see 120Hz noise. So I think the noise comes from the power brick and enters via the antenna. Sounds like the notebook power supply or the cables it connects to radiates RF. Not surprizing at all for a switching power supply Try installing some ferrite toroids on both of the cables on the power brick. Use as many turns as you can through the toroid. Another option is to use an antenna that is farther away from the power brick and bring the signal back using a long coax feed line. Use the inverse square law to your advantage. Chris Albertson Home: 310-376-1029 [EMAIL PROTECTED] Office: 310-336-5189 [EMAIL PROTECTED] Shape Yahoo! in your own image. Join our Network Research Panel today! http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7 ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Parameters for USRP (motherboard only) FM receiver
Hi, I'm trying to setup the USRP to receive and demodulate an FM signal at 175kHz. I have based my code on the wfm_rcv... examples, but I always get a "no suitable daughterboard found" error. I do not understand all of the parameters that I am setting on the USRP so I was wondering if anyone could explain them or point me to a resource on this. Basically, I know that I want the frequency to be 175kHz and I have gotten this to work with transmission, so I assume that's valid. I am more or less lost on decimation, interpolation etc. Any help is appreciated. -Shane ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] make check fail
Hi I have a fail when I did "make check" during gnuradio installation. FAIL: run_tests === 1 of 1 tests failed === make[6]: *** [check-TESTS] Error 1 make[6]: Leaving directory `/usr/src/gnuradio-3.0.3/gnuradio-core/src/python/gnu radio/gr' I checked same problem in the disscussion forum, I have the following in my Cygwin. but I still have "make check". SWIG Version 1.3.31, Compiled with g++ [i686-pc-cygwin] Python 2.4 gcc version 3.4.4 (cygming special, gdc 0.12, using dmd 0.125) $ find / -name libpython\* /bin/libpython2.5.dll /lib/python2.5/config/libpython2.5.dll.a /setup/Python-2.4-3/Python-2.4/Doc/lib/libpython.tex /setup/Python-2.4-3/Python-2.4/libpython2.4.a /setup/Python-2.4-3/Python-2.4/libpython2.4.dll /setup/Python-2.4-3/Python-2.4/libpython2.4.dll.a /usr/local/bin/libpython2.4.dll /usr/local/lib/python2.4/config/libpython2.4.dll.a /usr/bin/libpython2.5.dll /usr/lib/python2.5/config/libpython2.5.dll.a what shall I do please sorry for sending this again --Alaelddin ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GMSK: GSM initial phase for a burst
Jeffrey Karrels wrote: > Great suggestion! > > I have attached a couple of things: > 1) The IQ plot (1e6 sample rate) > 2) The burst data (MATLAB array) > 3) The da vs time plot. (1 symbol = 3.69us) > > Another quick question. I can now see that after the amplitude ramp > up that there is a short section of negative phase movement (.7 > radians clockwise) prior to the remaining counterclockwise rotations. > Should I expect a full (-pi/2) to start off the burst? Is my sampling > rate just not high enough to catch the remaining rotation? Any other > suggestions? I don't see anything at all wrong with this data. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
