This is merely a historical archive of years 2008-2021, before the migration to mailman3.
A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/osmocom-sdr@lists.osmocom.org/.
Sylvain AZARIAN sylvain.azarian at gmail.comMy personal tests on usb2 with Windows or Linux show a limit around 35 mbytes/sec (tested with Cypress fx2 or fx3) Sylvain Le 22 sept. 2013 18:36, "Ben Wojtowicz" <bwojtowi at gmail.com> a écrit : > All, > > I am using hackrf currently to receive LTE downlink at 15.36Msps. I have > not specifically tried it at 20Msps, but I believe it should work. USB2.0 > is certainly not the limiting factor for the rtl dongles' sample rate. > > Ben > On Sep 21, 2013 5:05 PM, "Nick Foster" <bistromath at gmail.com> wrote: > >> As others have tried to explain, this chip does not provide an analog >> output for you to digitize with your soundcard. It turns RF into H.264 >> digital video. That's all. There's nothing to digitize and no place to plug >> your soundcard into. >> >> --n >> What is all this talk about USB. High-end Audio Interfaces >> digitize/quantize >> at 192KHz/24bit. Since these new Tuners are almost naked on a surface >> mount >> board, all that is needed other than a good audio card is a BusPirate to >> control the I2C to get one of these new Analog TV tuner Chips to work as a >> SDR. Since most "Intelligence" in radio is narrow band typically a Voice >> Channel, all that a wideband A/D gives you is a view from 50,000 feet of >> the >> spectrum which is OK for Test and Measurement. I cannot use my TV Dongles >> for most of my (Forward Scatter RADAR) applications because of their low >> resolution, I must use a conventional Scanner because it converts the >> signal >> to Audio. What I need is high definition and narrow band, the current >> Dongles are typically Wide Band low resolution (2Mhz/8bit). This is why a >> Tuner Chip with low noise and demodulated analog output is attractive to >> me, >> it is a complete solution. >> >> -----Original Message----- >> From: osmocom-sdr-bounces at lists.osmocom.org >> [mailto:osmocom-sdr-bounces at lists.osmocom.org] On Behalf Of Leif Asbrink >> Sent: Saturday, September 21, 2013 4:38 PM >> To: osmocom-sdr at lists.osmocom.org >> Subject: Re: new TV Tuner Chip, the Si2177 >> >> Hi Adam, >> >> > > > The bandwidth of the I/Q pair is too large to be transmitted over >> > > > USB for the reception of TV signals. After demodulation the >> > > > bandwidth is lower so it would (marginally) fit an USB interface >> > > > if we talk about traditional analogue TV. For digital TV the >> > > > bandwidth reduction by the decoder is much larger. >> > >> > Is that correct? From what I can find, an analogue TV signal has a >> > bandwidth of around 6-8MHz. >> Yes. >> >> > The HackRF is an SDR that works over >> > USB2.0 and can capture a chunk of RF spectrum up to 20MHz, which >> > should be ample for one analogue (or even digital) TV signal, perhaps >> > even two if the channels are close enough together. >> >> I was under the impression that the USB channel was the reason that the >> highest sampling rate I was aware of in continous mode is 4 MHz >> (QS1R) Now, I did not think of the fact that for the dongle we need only 8 >> bit while normal SDRs use 16 bit so with my assumption the maximum >> sampling >> speed would be 8 MHz. To receive 6-8 MHz bandwidth one would need to >> sample >> quite a bit higher. Surely one could apply digital filters but even so a, >> substantial amount of oversampling is needed. >> >> Are you sure HackRF really can send 20 MHz of bandwidth over USB 2.0 >> continously? Where did you find that info? (Seems I should try to push SDR >> manufacturers who use USB 2.0 to supply modes with higher sampling >> rates...) >> >> 73 >> >> Leif >> >> ----- >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2013.0.3408 / Virus Database: 3222/6687 - Release Date: 09/21/13 >> >> >> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.osmocom.org/pipermail/osmocom-sdr/attachments/20130922/7c52b4f9/attachment.htm>