[Discuss-gnuradio] TVRX Kit - A Few Queries
I ordered Tvrx module and expect it to arrive at my place soon. Hope it will have a manual or imp guidelines on usage. Anyhow, I have a few basic questions : 1) What is range of the IF I can set its output to? 2) Can I use it for HDTV reception? 3) What is the max voltage swing in the output? Is there a DC offset in it? Waiting for a reply. Cheers! __ Prasanna ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: in-band signaling project overview
On 10/12/07, Jeff Brower <[EMAIL PROTECTED]> wrote: > ... > 2) Does your new FPGA code require the next-gen USRP, with Spartan 3 FPGA? > My understanding is that capacity is very > limited in the Cyclone, which is an old FPGA (around yr 2002 time-frame). If you have a single, specific application in mind, you should be able to reduce down the size taken in the USRP FPGA significantly. The original USRP FPGA was designed to be able to handle the most minimal decimation (4 by the CIC and 2 by the halfband FIR filter, I believe) which has the FIR computing every 8 clock cycles and an effective bandwidth of 8MHz. It was also designed for the CIC to handle large decimation rates which increases the "bit growth" of that filter. If you specifically have a bandwidth and decimation rate you're interested in (or even a small range of decimation rates) then you should be able to change the CIC filter to use significantly less space. Moreover, if you're decimating more than 4 at the CIC, you can use more clock cycles and less instantiated soft multipliers for the FIR filter in the FPGA. Just curious, what are you specifically looking to do? Do you need the ranges for the CIC decimation, or just a few select values? Can you handle having less CIC decimation and more FIR decimation? What waveforms are you looking at which causes latency to be so tight? Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: in-band signaling project overview
On 10/12/07, Jeff Brower <[EMAIL PROTECTED]> wrote: > I think the biggest concerns with Cyclone I are lack of multipliers and low > amount of > internal mem (26 kbyte for the EPC1C12). Understandable, but also remember that a CORDIC can perform a multiplication if you want it pipelined - and if you have a 64MHz clock with data coming out at 1Msps, you can perform a 64-tap FIR filter with only 1 multiplier instantiated. I can see where it is a concern, but it should be able to be circumvented relatively easily. I think a simple rake receiver might be possible at something like 1Msps and a 64MHz clock in that FPGA. > 802.11b (more specifically VoIP-over-WiFi), GSM (EDGE), and eventually 3G > (HSDPA) > waveforms. I've seen discussions and specific deadline figures for 802.11b, > but not > yet for the others -- do you know any web pages that show comparisons? > Thanks. I have not seen discussions with regards to those times, but I think GSM and HSDPA will be difficult strictly from an encryption standpoint. I thought the algorithms used for those protocols were under wraps and portions of the key are in your SIM card? As a curious note, why do you think there is a big push to do standards that are out there and already implemented efficiently in dedicated silicon? Do you have any intention on creating your own MAC protocol? Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: in-band signaling project overview
Brian- > > 2) Does your new FPGA code require the next-gen USRP, with Spartan 3 FPGA? > > My understanding is that capacity is very > > limited in the Cyclone, which is an old FPGA (around yr 2002 time-frame). > > If you have a single, specific application in mind, you should be able > to reduce down the size taken in the USRP FPGA significantly. > > The original USRP FPGA was designed to be able to handle the most > minimal decimation (4 by the CIC and 2 by the halfband FIR filter, I > believe) which has the FIR computing every 8 clock cycles and an > effective bandwidth of 8MHz. > > It was also designed for the CIC to handle large decimation rates > which increases the "bit growth" of that filter. If you specifically > have a bandwidth and decimation rate you're interested in (or even a > small range of decimation rates) then you should be able to change the > CIC filter to use significantly less space. Moreover, if you're > decimating more than 4 at the CIC, you can use more clock cycles and > less instantiated soft multipliers for the FIR filter in the FPGA. I think the biggest concerns with Cyclone I are lack of multipliers and low amount of internal mem (26 kbyte for the EPC1C12). > Just curious, what are you specifically looking to do? Do you need > the ranges for the CIC decimation, or just a few select values? Can > you handle having less CIC decimation and more FIR decimation? What > waveforms are you looking at which causes latency to be so tight? 802.11b (more specifically VoIP-over-WiFi), GSM (EDGE), and eventually 3G (HSDPA) waveforms. I've seen discussions and specific deadline figures for 802.11b, but not yet for the others -- do you know any web pages that show comparisons? Thanks. -Jeff ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: in-band signaling project overview
Brian- > On 10/12/07, Jeff Brower <[EMAIL PROTECTED]> wrote: > > I think the biggest concerns with Cyclone I are lack of multipliers and low > > amount of > > internal mem (26 kbyte for the EPC1C12). > > Understandable, but also remember that a CORDIC can perform a > multiplication if you want it pipelined - and if you have a 64MHz > clock with data coming out at 1Msps, you can perform a 64-tap FIR > filter with only 1 multiplier instantiated. > > I can see where it is a concern, but it should be able to be > circumvented relatively easily. I think a simple rake receiver might > be possible at something like 1Msps and a 64MHz clock in that FPGA. > > > 802.11b (more specifically VoIP-over-WiFi), GSM (EDGE), and eventually 3G > > (HSDPA) > > waveforms. I've seen discussions and specific deadline figures for > > 802.11b, but not > > yet for the others -- do you know any web pages that show comparisons? > > Thanks. > > I have not seen discussions with regards to those times, but I think > GSM and HSDPA will be difficult strictly from an encryption > standpoint. I thought the algorithms used for those protocols were > under wraps and portions of the key are in your SIM card? If you own both ends (or maybe better said "if it's your data in the first place") this is not an issue. > As a curious note, why do you think there is a big push to do > standards that are out there and already implemented efficiently in > dedicated silicon? I work mostly in the infrastructure side of things. I'm not sure why people are pushing to build things like their own software-based GSM receiver -- that's a good question actually. In my area, as one example, typical basestations cost 70 to 100k. An SDR server with a PCI/PCIe card containing an FPGA + some DSPs could reduce this cost by a factor of 10. > Do you have any intention on creating your own MAC protocol? No. -Jeff ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
RE: [Discuss-gnuradio] TVRX Kit - A Few Queries
>>I ordered Tvrx module and expect it to arrive at my place soon. Hope it will have a manual or imp guidelines on usage. The TVRX will not come with a manual or guidelines on usage. You can find the schematics at http://gnuradio.org/trac/browser/usrp-hw/trunk/tvrx The TVRX module has a Microtune 4937 Tuner Module and here is a link to the datasheet for that http://www.comsec.com/usrp/microtune/4937-DI5-3x8899-2.pdf >>1) What is range of the IF I can set its output to? It has a fixed IF at 44Mhz I believe. A different version of the same tuner module comes with 5.75Mhz IF. Matt, please correct me if I am wrong. >>2) Can I use it for HDTV reception? Yes you can use it for HDTV reception. I am trying to do the same thing and am halfway there. I suggest you start with FM reception or something pretty basic using examples in gnuradio-examples directory. >>3) What is the max voltage swing in the output? Is there a DC offset in it? Ref datasheet mentioned above. Nirali Patel ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Re: in-band signaling project overview
Brian- > > 2) Does your new FPGA code require the next-gen USRP, with Spartan 3 FPGA? > > My understanding is that capacity is very > > limited in the Cyclone, which is an old FPGA (around yr 2002 time-frame). > > If you have a single, specific application in mind, you should be able > to reduce down the size taken in the USRP FPGA significantly. > > The original USRP FPGA was designed to be able to handle the most > minimal decimation (4 by the CIC and 2 by the halfband FIR filter, I > believe) which has the FIR computing every 8 clock cycles and an > effective bandwidth of 8MHz. > > It was also designed for the CIC to handle large decimation rates > which increases the "bit growth" of that filter. If you specifically > have a bandwidth and decimation rate you're interested in (or even a > small range of decimation rates) then you should be able to change the > CIC filter to use significantly less space. Moreover, if you're > decimating more than 4 at the CIC, you can use more clock cycles and > less instantiated soft multipliers for the FIR filter in the FPGA. I think the biggest concerns with Cyclone I are lack of multipliers and low amount of internal mem (26 kbyte for the EPC1C12). > Just curious, what are you specifically looking to do? Do you need > the ranges for the CIC decimation, or just a few select values? Can > you handle having less CIC decimation and more FIR decimation? What > waveforms are you looking at which causes latency to be so tight? 802.11b (more specifically VoIP-over-WiFi), GSM (EDGE), and eventually 3G (HSDPA) waveforms. I've seen discussions and specific deadline figures for 802.11b, but not yet for the others -- do you know any web pages that show comparisons? Thanks. -Jeff ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Contribute to the in-band project: profile the code
Dominik Auras wrote: Hi! I have tried to profile your code. Thank you! :D What are your machine specs? First thing I noted: The PMT library from your svn branch had to be installed with sudo make install. Now I installed the whole branch. Yes, I forgot to mention this, thank you! I will add it to the wiki. Next thing: When I run test_usrp_inband_rx, it takes very long time and produces messages: fusb: (rd status -2) No such file or directory Interesting... I thought we had solved this with a commit before my e-mail of a USB patch Eric gave me. I tested it with at least 50 runs on my machine and never saw it again after the patch. Can you try doing a hard reset on the board (unplug/replug) and try running this again? These appear after "Closing the USRP". There is cpu usage only after this message, and only one core is used (is that right?). It takes more than 8 minutes, not 40s as in your example in the wiki. Since it appeared to hang, I have interrupted the execution. Yes this is too long. To make a long story short there seems to be a problem clearing the buffers in the FX2 which the USRP hangs on "Closing the USRP" because it's waiting for the buffers to clear... we think! Do a hard reset and try again, does it produce this error every time? - George ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] USRP to USRP communication over air
Hello, I am Archana from the University of Maryland,College Park. I have two USRPs connected to two laptops. The USRPs have antennae connected to them. Basically I am trying to get the two USRPs communicate with each other using OFDM. I started by playing around with the ofdm_benchmark_tx.py and ofdm_benchmark_rx.py scripts but it's not giving me an idea of how to go about things. Can someone please throw some light on this? Any help will be greatly appreciated!! Regards, -- Archana Ragothaman Master's in Telecommunications Graduate Research Assistant MIND Lab,UMIACS University of Maryland, College Park Email: [EMAIL PROTECTED] Phone: 240-422-7887 ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] TVRX Kit - A Few Queries
>>> 1) What is range of the IF I can set its output to? >>> > It has a fixed IF at 44Mhz I believe. A different version of the same tuner > module comes with 5.75Mhz IF. Matt, please correct me if I am wrong. > Yes, the shippingones have an IF of 44 MHz. The older ones were 5.75 MHz, but from the user's point of view, it doesn't matter. You don't need to know the IF. Matt ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] usrp_prims python module missing
Johnathan Corgan wrote: Paul Creekmore wrote: The only package I've ever installed was 3.0.2. I've done so once with Synaptic Package Manager and once with apt-get. I see no mention of usrpm. Specifically, usrp_fft.py imports usrp.py, and usrp.py imports usrp_prims and usrp_dbid, neither of which exist in my installation. I am sorry--I was mistaken on my end (long day...) I just downloaded and looked through the 3.0.2 packages--the two files you need are both located in the 'python-usrp' package, so make sure that is installed. Problem solved. My Debian installation did not by default include one of the very critical Debian package download mirrors in apt-get's sources.list file, so I was indeed missing python-usrp, among other things. For the record, to allow apt-get to find all necessary GNU Radio/USRP packages, I added deb http://http.us.debian.org/debian sid main contrib to /etc/apt/sources.list --Paul ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Contribute to the in-band project: profile the code
OK sorry for the flood :P I've finally been able to reproduce this error on another one of my machines... it does not seem to occur at all on two of my machines, but on a third it does. Looking in to this now. - George ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] TVRX Kit - A Few Queries
Matt Ettus wrote: > > Yes, the shippingones have an IF of 44 MHz. The older ones were 5.75 > MHz, but from the user's point of view, it doesn't matter. You don't > need to know the IF. > > > > Matt > Actually that's something I was curious about as well. I'll likely be picking up a TV_RX for this project here: http://tech.groups.yahoo.com/group/sbrac-astronomy/ In the next few months. The dish surface is good to about 1.5Ghz, but was originally designed for ballpark 400Mhz. I'm trying to get a multi-faceted radio astronomy and SETI program going on this thing, and Pulsars are stronger down around 400Mhz than at 1420Mhz. The dish is 18M or so in diameter. So, anything that works with the DBS_RX works also with the TV_RX? Is the tuner real-mode only, and do you synthesize I and Q in the FPGA? 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] Contribute to the in-band project: profile the code
George Nychis wrote: These appear after "Closing the USRP". There is cpu usage only after this message, and only one core is used (is that right?). It takes more than 8 minutes, not 40s as in your example in the wiki. Since it appeared to hang, I have interrupted the execution. One more thing, can you monitor your memory usage before seeing this message? - George ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Contribute to the in-band project: profile the code
Hi! I have tried to profile your code. First thing I noted: The PMT library from your svn branch had to be installed with sudo make install. Now I installed the whole branch. Next thing: When I run test_usrp_inband_rx, it takes very long time and produces messages: fusb: (rd status -2) No such file or directory These appear after "Closing the USRP". There is cpu usage only after this message, and only one core is used (is that right?). It takes more than 8 minutes, not 40s as in your example in the wiki. Since it appeared to hang, I have interrupted the execution. I followed all instructions, from retrieving the branch up to getting the new RBF file. My USRPs are from revision 4.2. My linux is Ubuntu Gutsy Gibbon. Instead of the linux kernel you specified, I downloaded the source of my kernel. Dominik ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
RE: [Discuss-gnuradio] Unable to find field sync for over the air HDTV signal
Hello Eric, > [In looking at interp.py, it could be modified to run something like > 4x faster by using gr.interp_fir_filter_ccf instead of what's in > there. Also, decimating by 10 seems a bit agressive. By 8 would give > you more usable signal, though would require changes in the interp.py > code.] I have gotten a set of RAID 0 drives installed and now I can write with a decimation factor of 8 without any overruns. I would like to modify interp.py to appropriately interpolate and lowpass filter the 8 Msps signal from the USRP. Would it be sufficient if I interpolate by 2? Or do I need a higher, maybe fractional interpolation rate? I am also unsure of what the filter cut-off frequency would need to be after the proper interpolation. If you have any suggestions it would be a great help! Thanks, Nirali ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] using an external clock with the RFX 900
Hi there, I've got a USRP v4 board that I'm planning to run off of a 13Mhz external clock. I know how to modify the hardware and software accordingly. (I hope.) However, I'm intending to use a pair of RFX 900 daughterboards, and I'm wondering if there are any known mods needed to allow these daughterboards to operate with a 13Mhz clock? Thanks, Harvind ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] TVRX Kit - A Few Queries
If IF is at 44MHz, is it further downconverted(to around 5-15MHz) before being fed to the ADC? I just want to know this out of curiosity. Pls let me know. _ Cheers! Prasanna On 10/12/07, Nirali Patel <[EMAIL PROTECTED]> wrote: > > >>I ordered Tvrx module and expect it to arrive at my place soon. Hope it > will have a manual or imp guidelines on usage. > > The TVRX will not come with a manual or guidelines on usage. You can find > the schematics at http://gnuradio.org/trac/browser/usrp-hw/trunk/tvrx > The TVRX module has a Microtune 4937 Tuner Module and here is a link to > the > datasheet for that > http://www.comsec.com/usrp/microtune/4937-DI5-3x8899-2.pdf > > >>1) What is range of the IF I can set its output to? > It has a fixed IF at 44Mhz I believe. A different version of the same > tuner > module comes with 5.75Mhz IF. Matt, please correct me if I am wrong. > > >>2) Can I use it for HDTV reception? > Yes you can use it for HDTV reception. I am trying to do the same thing > and > am halfway there. I suggest you start with FM reception or something > pretty > basic using examples in gnuradio-examples directory. > > >>3) What is the max voltage swing in the output? Is there a DC offset in > it? > Ref datasheet mentioned above. > > > Nirali Patel > > > > ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
