[USRP-users] Re: Quick question about tuning USRP B210 for sweep spectrum
Something to note regarding the TwinRX is that changing frequency on one channel has an effect on the other channel of the same card. I ran into this a few years ago and never found a resolution. My goal was to sweep with one channel and stare with the other. The staring channel had too many artifacts from the sweeping channel to be useful for my application. Also, the TwinRX is pretty flat for around 80 MHz of BW. Brian On Thu, May 2, 2024 at 8:41 AM Marcus D. Leech wrote: > On 02/05/2024 08:25, Olo via USRP-users wrote: > > I got 8GHz info from: > https://www.rtl-sdr.com/hackrf-sweep-spectrum-analyzer-windows/ > > I want to express my gratitude for your prompt responses and assistance > thus far. Your support has been valuable. > > However, I have a specific query regarding optimizing performance for a > particular goal. In the GitHub repository under > *uhd/host/examples/twinrx_freq_hopping.cpp*, you mentioned the importance > of directly setting the LO frequency for better performance. Additionally, > you described a method of accessing the LO wherein one LO is set for > transmission while another operates for reception simultaneously. Is this > recommended way to make sweep spectrum (with x310)? > > I didn't write twinrx_freq_hopping.cpp, and furthermore, it has no > transmit capability at all. > > I'm curious if there are more such techniques or tricks to achieve optimal > performance. > Thank you once again for your attention to this matter. > > Given that the X310 supports 2 TwinRX cards, that could give you up to > 200MHz of instantaneous bandwidth if each channel > (2 channels per TwinRX) is delivering 50Mhz of bandwidth. With > 5msec/hop (as shown in twinrx_freq_hopping), that's > 40GHz/second. > > > > Olo > > On Wednesday, May 1st, 2024 at 20:42, Olo via USRP-users > wrote: > > Would it be possible, with the USRP X310 with TwinRX (or two TwinRX > units), to achieve the mentioned goal? If so, could you please explain the > approach to accomplish this? Thank you. > > On Tuesday, April 30th, 2024 at 9:20, Olo > wrote: > > Hi there, > > I'm USRP B210 for a project. I'm trying to make a sweep spectrum analyzer > that scans frequencies quickly. Currently, I'm tuning frequencies like this > (which is I think the main issue): > > tune_request = uhd.types.TuneRequest(self.steps[self.i], 1.0)result = > self.usrp_device.set_rx_freq(tune_request, self.rx_info.ch) > I'm programming it in PyQt, and I've created a stream like this: > > self.stream_cmd_start = uhd.types.StreamCMD(uhd.types.StreamMode.num_done). > > (Because I've noticed that for a continuous stream, it takes eternity to > retune.) > > Do you have any tips on how to do this faster? Any advice or code examples > would be really helpful. > > > Thanks a lot, > > Olo. > > > > > ___ > USRP-users mailing list -- usrp-users@lists.ettus.com > To unsubscribe send an email to usrp-users-le...@lists.ettus.com > > > ___ > USRP-users mailing list -- usrp-users@lists.ettus.com > To unsubscribe send an email to usrp-users-le...@lists.ettus.com > ___ USRP-users mailing list -- usrp-users@lists.ettus.com To unsubscribe send an email to usrp-users-le...@lists.ettus.com
[USRP-users] Re: Quick question about tuning USRP B210 for sweep spectrum
On 02/05/2024 08:25, Olo via USRP-users wrote: I got 8GHz info from: https://www.rtl-sdr.com/hackrf-sweep-spectrum-analyzer-windows/ I want to express my gratitude for your prompt responses and assistance thus far. Your support has been valuable. However, I have a specific query regarding optimizing performance for a particular goal. In the GitHub repository under *uhd/host/examples/twinrx_freq_hopping.cpp*, you mentioned the importance of directly setting the LO frequency for better performance. Additionally, you described a method of accessing the LO wherein one LO is set for transmission while another operates for reception simultaneously. Is this recommended way to make sweep spectrum (with x310)? I didn't write twinrx_freq_hopping.cpp, and furthermore, it has no transmit capability at all. I'm curious if there are more such techniques or tricks to achieve optimal performance. Thank you once again for your attention to this matter. Given that the X310 supports 2 TwinRX cards, that could give you up to 200MHz of instantaneous bandwidth if each channel (2 channels per TwinRX) is delivering 50Mhz of bandwidth. With 5msec/hop (as shown in twinrx_freq_hopping), that's 40GHz/second. Olo On Wednesday, May 1st, 2024 at 20:42, Olo via USRP-users wrote: Would it be possible, with the USRP X310 with TwinRX (or two TwinRX units), to achieve the mentioned goal? If so, could you please explain the approach to accomplish this? Thank you. On Tuesday, April 30th, 2024 at 9:20, Olo wrote: Hi there, I'm USRP B210 for a project. I'm trying to make a sweep spectrum analyzer that scans frequencies quickly. Currently, I'm tuning frequencies like this (which is I think the main issue): tune_request = uhd.types.TuneRequest(self.steps[self.i], 1.0) result = self.usrp_device.set_rx_freq(tune_request, self.rx_info.ch) I'm programming it in PyQt, and I've created a stream like this: self.stream_cmd_start = uhd.types.StreamCMD(uhd.types.StreamMode.num_done). (Because I've noticed that for a continuous stream, it takes eternity to retune.) Do you have any tips on how to do this faster? Any advice or code examples would be really helpful. Thanks a lot, Olo. ___ USRP-users mailing list --usrp-users@lists.ettus.com To unsubscribe send an email tousrp-users-le...@lists.ettus.com ___ USRP-users mailing list -- usrp-users@lists.ettus.com To unsubscribe send an email to usrp-users-le...@lists.ettus.com
[USRP-users] Re: Quick question about tuning USRP B210 for sweep spectrum
On 02/05/2024 07:38, Olo via USRP-users wrote: Goal is to find the limits. The HackRF for example can do 8GHz per second sweep. So lets consider that as example. Assuming 20Mhz/tuning (I think HackRF supports a maximum of 20Mhz bandwidth), that's 2.5msec/tuning. The X310 with the TwinRX can support 80MHz of bandwidth, and the synthesizer probably locks in under 2msec for 250MHz jump in frequency. On Wednesday, May 1st, 2024 at 20:42, Olo via USRP-users wrote: Would it be possible, with the USRP X310 with TwinRX (or two TwinRX units), to achieve the mentioned goal? If so, could you please explain the approach to accomplish this? Thank you. On Tuesday, April 30th, 2024 at 9:20, Olo wrote: Hi there, I'm USRP B210 for a project. I'm trying to make a sweep spectrum analyzer that scans frequencies quickly. Currently, I'm tuning frequencies like this (which is I think the main issue): tune_request = uhd.types.TuneRequest(self.steps[self.i], 1.0) result = self.usrp_device.set_rx_freq(tune_request, self.rx_info.ch) I'm programming it in PyQt, and I've created a stream like this: self.stream_cmd_start = uhd.types.StreamCMD(uhd.types.StreamMode.num_done). (Because I've noticed that for a continuous stream, it takes eternity to retune.) Do you have any tips on how to do this faster? Any advice or code examples would be really helpful. Thanks a lot, Olo. ___ USRP-users mailing list --usrp-users@lists.ettus.com To unsubscribe send an email tousrp-users-le...@lists.ettus.com ___ USRP-users mailing list -- usrp-users@lists.ettus.com To unsubscribe send an email to usrp-users-le...@lists.ettus.com
[USRP-users] Re: Quick question about tuning USRP B210 for sweep spectrum
How fast do you need to tune it? No synthesizer that is optimized to reduce phase noise and frequency error can tune instantly. What is the scale of the goal? Sent from my iPhone > On May 1, 2024, at 2:42 PM, Olo via USRP-users > wrote: > > > Would it be possible, with the USRP X310 with TwinRX (or two TwinRX units), > to achieve the mentioned goal? If so, could you please explain the approach > to accomplish this? Thank you. > >> On Tuesday, April 30th, 2024 at 9:20, Olo wrote: >> Hi there, >> >> I'm USRP B210 for a project. I'm trying to make a sweep spectrum analyzer >> that scans frequencies quickly. Currently, I'm tuning frequencies like this >> (which is I think the main issue): >> >> tune_request = uhd.types.TuneRequest(self.steps[self.i], 1.0) >> result = self.usrp_device.set_rx_freq(tune_request, self.rx_info.ch) >> >> I'm programming it in PyQt, and I've created a stream like this: >> self.stream_cmd_start = uhd.types.StreamCMD(uhd.types.StreamMode.num_done). >> (Because I've noticed that for a continuous stream, it takes eternity to >> retune.) >> Do you have any tips on how to do this faster? Any advice or code examples >> would be really helpful. >> >> Thanks a lot, >> >> Olo. >> > > ___ > USRP-users mailing list -- usrp-users@lists.ettus.com > To unsubscribe send an email to usrp-users-le...@lists.ettus.com ___ USRP-users mailing list -- usrp-users@lists.ettus.com To unsubscribe send an email to usrp-users-le...@lists.ettus.com
[USRP-users] Re: Quick question about tuning USRP B210 for sweep spectrum
On 30/04/2024 03:20, Olo via USRP-users wrote: Hi there, I'm USRP B210 for a project. I'm trying to make a sweep spectrum analyzer that scans frequencies quickly. Currently, I'm tuning frequencies like this (which is I think the main issue): tune_request = uhd.types.TuneRequest(self.steps[self.i], 1.0) result = self.usrp_device.set_rx_freq(tune_request, self.rx_info.ch) I'm programming it in PyQt, and I've created a stream like this: self.stream_cmd_start = uhd.types.StreamCMD(uhd.types.StreamMode.num_done). (Because I've noticed that for a continuous stream, it takes eternity to retune.) Do you have any tips on how to do this faster? Any advice or code examples would be really helpful. Thanks a lot, Olo. ___ USRP-users mailing list --usrp-users@lists.ettus.com To unsubscribe send an email tousrp-users-le...@lists.ettus.com The synthesizer on the AD9361 is known to be relatively slow. While UHD tries to optimize things for tunings that are within about 100MHz of each other, you can see tune times as high as 100msec. The AD9361 chip inside the B210 simply isn't optimized for rapid tuning -- at least the way UHD uses it. The chip does have a "cache" mechanism, where synthesizer register values and various gain and I/Q calibration values can be pre-stored, and you "tune' using those registers. The register cache isn't that large, AFAIR, but none of that is exposed in UHD. ___ USRP-users mailing list -- usrp-users@lists.ettus.com To unsubscribe send an email to usrp-users-le...@lists.ettus.com
