Re: [Discuss-gnuradio] python/digital examples and UHD
On Tue, Nov 30, 2010 at 4:05 AM, Moritz Fischer fisc...@int.uni-karlsruhe.de wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 11/29/2010 03:47 PM, Tom Rondeau wrote: Thanks for your reply Tom, Have you used the version 2 digital code, yet (benchmark_tx2, benchmark_rx2, usrp_receive_path2, etc.)? One of the things I did was include better resampling so that you can get any bit rate you want. You still have to go through the process of selecting the USRP's sample rate that's closest to your desired rate, and then the resampling takes care of the rest. Well in fact that's what I was looking at. I called this the 'automagical' frequency selection in my last mail ;-) It appears to me you do this by trying all the tuples of (bitrate, samples_per_symbol,...) and select the one fitting 'best'. So please don't throw stones at me for asking this question, but from my understanding the required desired_samplerate = bitrate x samples_per_symbol / bits_per_symbol (1) Yep: (bits/sec) x (samps/sym) / (bits/sym) = samps/sec What I do with the UHD driver is ask for a sample rate. It will then set its sample rate to whatever the closest rate it can do. You can the read back the actual sample rate of the USRP with get_samp_rate(). I then use this value to determine the difference between my desired sample rate and the actual sample rate, which I then plug into the arbitrary resampler. So what you suggest is basically: 1. set_samp_rate(desired_samplerate) as in (1) 2. tmp = get_samp_rate() 3. and then resample in gnuradio according to tmp / desired_samplerate or did I get something wrong? Nope, that's what I've done. Works great. Eventually, it'd be great to put the arbitrary resampler into the USRP. It should be easy to fit this into the N210's FPGA. But for just use the pfb_arb_resampler_ccf block. You'll need to build a set of filter taps for it, which you can find out how to do this in gnuradio-examples/python/pfb/interpolate.py. Tom Please don't get me wrong because I ask a lot of questions :-) I don't ask you guys to do any of my work (like a thesis or the likes). Just in my opinion having the examples working is really important, because that's where new people start to look at when trying to figure out how stuff works. And nothing is more frustrating than not even managing to get the examples running. Best regards and happy hacking, Moritz -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAEBAgAGBQJM9L5tAAoJEOjnDXL6I0uZtNwP/1JDIggYhvBRw6bJQmQzUjKU mDKrYyqIdFbLDv0+aC62gTn0g+OVpa11yP585pZcF9tZ5A9ZwIqSEpo6iEPXH883 q6+A3GmogTAqtaydf7seG3PkdV/HXZcAkBRtd0QgjMykKbIOG2hlDTJZsv8Ru0Iz /dOa6ERrxHQSrYY1DLW/e5dMrwBp8SMGdIT3RlwpuKvQyZmA9xj8rcqxNyvfHuNf 3KT5AFCQQbKrmGXiwb9z+09rFTHWga4hdLbfkX+L4ANz/j2eUDxomLgSVcx1vOEb 0Qqn1MJu2vBRceIdyiAItl3gnocWZ62EQMnvIcoDY9F7Mi9sBCWVV18CWVwPv2SU P+4o5wRvpV5b7nVn6U0Yi47w0/Wfz5UsYbiGMc/scrpSa0wHuYv7BXsjlOOANrmd RAYz0Xvk6aIq4P4RuuqeIx1AWfw0tLcQaO7BAAvanZqf6qf+HqP+oMmCQZgWzlhL hgDuL/7YdpUN66c8xSXivCfFZpf/FOkoKMhF1N7BQ1EM349BrgbPdL3VO0I/jEs/ f7nsMML7FkhJdOF5IH/1QgEl+fGGMNvEmqBqfm3w/pYtUkwX4KDnc6GrHimYrk72 QnFuv2ZWURnyNsvp7pYnH27Bu7ssyYa6DZP+Iu047Ev7iK0oMuqaQaWxDibSSL4c vMqE5g//R0SsNBcTtiZe =x5g+ -END PGP SIGNATURE- ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] python/digital examples and UHD
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 11/29/2010 03:47 PM, Tom Rondeau wrote: Thanks for your reply Tom, Have you used the version 2 digital code, yet (benchmark_tx2, benchmark_rx2, usrp_receive_path2, etc.)? One of the things I did was include better resampling so that you can get any bit rate you want. You still have to go through the process of selecting the USRP's sample rate that's closest to your desired rate, and then the resampling takes care of the rest. Well in fact that's what I was looking at. I called this the 'automagical' frequency selection in my last mail ;-) It appears to me you do this by trying all the tuples of (bitrate, samples_per_symbol,...) and select the one fitting 'best'. So please don't throw stones at me for asking this question, but from my understanding the required desired_samplerate = bitrate x samples_per_symbol / bits_per_symbol (1) What I do with the UHD driver is ask for a sample rate. It will then set its sample rate to whatever the closest rate it can do. You can the read back the actual sample rate of the USRP with get_samp_rate(). I then use this value to determine the difference between my desired sample rate and the actual sample rate, which I then plug into the arbitrary resampler. So what you suggest is basically: 1. set_samp_rate(desired_samplerate) as in (1) 2. tmp = get_samp_rate() 3. and then resample in gnuradio according to tmp / desired_samplerate or did I get something wrong? Please don't get me wrong because I ask a lot of questions :-) I don't ask you guys to do any of my work (like a thesis or the likes). Just in my opinion having the examples working is really important, because that's where new people start to look at when trying to figure out how stuff works. And nothing is more frustrating than not even managing to get the examples running. Best regards and happy hacking, Moritz -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAEBAgAGBQJM9L5tAAoJEOjnDXL6I0uZtNwP/1JDIggYhvBRw6bJQmQzUjKU mDKrYyqIdFbLDv0+aC62gTn0g+OVpa11yP585pZcF9tZ5A9ZwIqSEpo6iEPXH883 q6+A3GmogTAqtaydf7seG3PkdV/HXZcAkBRtd0QgjMykKbIOG2hlDTJZsv8Ru0Iz /dOa6ERrxHQSrYY1DLW/e5dMrwBp8SMGdIT3RlwpuKvQyZmA9xj8rcqxNyvfHuNf 3KT5AFCQQbKrmGXiwb9z+09rFTHWga4hdLbfkX+L4ANz/j2eUDxomLgSVcx1vOEb 0Qqn1MJu2vBRceIdyiAItl3gnocWZ62EQMnvIcoDY9F7Mi9sBCWVV18CWVwPv2SU P+4o5wRvpV5b7nVn6U0Yi47w0/Wfz5UsYbiGMc/scrpSa0wHuYv7BXsjlOOANrmd RAYz0Xvk6aIq4P4RuuqeIx1AWfw0tLcQaO7BAAvanZqf6qf+HqP+oMmCQZgWzlhL hgDuL/7YdpUN66c8xSXivCfFZpf/FOkoKMhF1N7BQ1EM349BrgbPdL3VO0I/jEs/ f7nsMML7FkhJdOF5IH/1QgEl+fGGMNvEmqBqfm3w/pYtUkwX4KDnc6GrHimYrk72 QnFuv2ZWURnyNsvp7pYnH27Bu7ssyYa6DZP+Iu047Ev7iK0oMuqaQaWxDibSSL4c vMqE5g//R0SsNBcTtiZe =x5g+ -END PGP SIGNATURE- ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] python/digital examples and UHD
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi list, over the weekend I spend some time trying to update the demos to work with the UHD, I just started playing with git, so if you see something stupid let me know ;-) I put what I got on (in the uhd-examples branch): g...@github.com:mfischer/gnuradio-mfischer.git However the part where it 'automagically' picks rx/tx bitrates is not really working as I have no idea how to detect what device I'm talking to. Also please note that as I don't have the right values for bitrates and samples_per_symbol don't be surprised if the examples crash ;-) The old generic_usrp.py had ranges for the possible decimation / interpolation factors as we don't have this in UHD I'm a bit confused on how to continue. I started to add a function samp_rate_range_t get_rx_samp_rate_range() to UHDs single_usrp_sink / multi_usrp_sink which internally would ask the corresponding _dev for the right ranges, depending on what device you're talking to. I still have to figure out the ranges part though. g...@github.com:mfischer/uhd-mfischer.git As I don't really have insight into the longtime plan for UHD, I'm not sure whether that's the way to go though... Can someone give me any hints whether this actually makes sense? Happy hacking, - -Moritz -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJM82xBAAoJEOjnDXL6I0uZ4icQAJt3+Z82fs2LGRZ+4ndKVat0 DMPzRW1EN3T4EKIyAY9N4/weLwXvT5vuyKc+2i/mlPzhjS+ssJKfsnbLJNfNgK0Q Notdvyv1ItNZtrD2/l5MpM/dyR0dwVpLJnmF6jrH0zOX0yiBdah80/YAz5ISrxtm nKNmo0DJ/hZqWPQkklYbMrDirdLACPTzRwqh+JVJHBOOiVnoyXbmxakY2Ta1Ea+d 4BpOOV4h5daGQeC+9BKODY/aNtkemCvHBZdC3FQA/8IxnoRnJWTohT4Dyxc+Ypgo AKOaYUGk1uPuJ1JrCP1883umBBm5Pf4x4Obe0yJ8s3RXWuWB80f40Kx/Qbc4CXnG e3rXN50E4lF76JZm4bJqzlextQ28bXRVkeCM+AeaM/nTECRHaY2QhQhAWCA2iFCC /amJjdQpm8fiDk1gx1hpXWeQk2eyvx3Uy4Oe9L5JgiVMFBD+4yvwqIqGcRwIxo/i ladOfOTiJ9d0tcYXZ9Injg4QDAtHwtmFO8nF8WVnzvPlPHiGQaOwpgtJu7aPJRt/ +96HR/lT7VFCGmawJbsig4jbXgSQ0oxsRkJ6A+IxjCDN56wtABiyIdbu0575BU7w I/SjuIZ6xe9H+NFs/ZYmb5ImMiZFq2fV3Tn3ljZJrcaf1IMRQ+a2yoSgo4In5O7C +7H/Ru9tHCRR5J52m587 =AHQt -END PGP SIGNATURE- ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] python/digital examples and UHD
On Mon, Nov 29, 2010 at 4:02 AM, Moritz Fischer fisc...@int.uni-karlsruhe.de wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi list, over the weekend I spend some time trying to update the demos to work with the UHD, I just started playing with git, so if you see something stupid let me know ;-) I put what I got on (in the uhd-examples branch): g...@github.com:mfischer/gnuradio-mfischer.git However the part where it 'automagically' picks rx/tx bitrates is not really working as I have no idea how to detect what device I'm talking to. Also please note that as I don't have the right values for bitrates and samples_per_symbol don't be surprised if the examples crash ;-) The old generic_usrp.py had ranges for the possible decimation / interpolation factors as we don't have this in UHD I'm a bit confused on how to continue. I started to add a function samp_rate_range_t get_rx_samp_rate_range() to UHDs single_usrp_sink / multi_usrp_sink which internally would ask the corresponding _dev for the right ranges, depending on what device you're talking to. I still have to figure out the ranges part though. g...@github.com:mfischer/uhd-mfischer.git As I don't really have insight into the longtime plan for UHD, I'm not sure whether that's the way to go though... Can someone give me any hints whether this actually makes sense? Happy hacking, - -Moritz Thanks, Moritz. I'll try to take a look at this sometime. Have you used the version 2 digital code, yet (benchmark_tx2, benchmark_rx2, usrp_receive_path2, etc.)? One of the things I did was include better resampling so that you can get any bit rate you want. You still have to go through the process of selecting the USRP's sample rate that's closest to your desired rate, and then the resampling takes care of the rest. What I do with the UHD driver is ask for a sample rate. It will then set its sample rate to whatever the closest rate it can do. You can the read back the actual sample rate of the USRP with get_samp_rate(). I then use this value to determine the difference between my desired sample rate and the actual sample rate, which I then plug into the arbitrary resampler. Tom -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJM82xBAAoJEOjnDXL6I0uZ4icQAJt3+Z82fs2LGRZ+4ndKVat0 DMPzRW1EN3T4EKIyAY9N4/weLwXvT5vuyKc+2i/mlPzhjS+ssJKfsnbLJNfNgK0Q Notdvyv1ItNZtrD2/l5MpM/dyR0dwVpLJnmF6jrH0zOX0yiBdah80/YAz5ISrxtm nKNmo0DJ/hZqWPQkklYbMrDirdLACPTzRwqh+JVJHBOOiVnoyXbmxakY2Ta1Ea+d 4BpOOV4h5daGQeC+9BKODY/aNtkemCvHBZdC3FQA/8IxnoRnJWTohT4Dyxc+Ypgo AKOaYUGk1uPuJ1JrCP1883umBBm5Pf4x4Obe0yJ8s3RXWuWB80f40Kx/Qbc4CXnG e3rXN50E4lF76JZm4bJqzlextQ28bXRVkeCM+AeaM/nTECRHaY2QhQhAWCA2iFCC /amJjdQpm8fiDk1gx1hpXWeQk2eyvx3Uy4Oe9L5JgiVMFBD+4yvwqIqGcRwIxo/i ladOfOTiJ9d0tcYXZ9Injg4QDAtHwtmFO8nF8WVnzvPlPHiGQaOwpgtJu7aPJRt/ +96HR/lT7VFCGmawJbsig4jbXgSQ0oxsRkJ6A+IxjCDN56wtABiyIdbu0575BU7w I/SjuIZ6xe9H+NFs/ZYmb5ImMiZFq2fV3Tn3ljZJrcaf1IMRQ+a2yoSgo4In5O7C +7H/Ru9tHCRR5J52m587 =AHQt -END PGP SIGNATURE- ___ 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
