Re: [Flexradio] mobile sdr and a complete spectrum display
Sounds like a future feature request to me.. Jim, WD7R -Original Message- From: Philip Covington [mailto:p.coving...@gmail.com] Sent: Friday, June 19, 2009 6:22 AM To: Ray Andrews, K9DUR Cc: Jim; flexradio@flex-radio.biz Subject: Re: [Flexradio] mobile sdr and a complete spectrum display On Fri, Jun 19, 2009 at 9:04 AM, Ray Andrews, K9DUR wrote: > Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, > a communications link with the bandwidth neseccary to handle the resulting > data stream, and the CPU power required to process that 40 MHz bandwidth > digital stream in real time, it would be possible to display the entire HF > spectrum at one time. Of course, you would also need a monitor a couple of > hundred feet wide to make the display useablehi..hi. Seriously, an A/D > with these capabilities would be prohibitively expensive, the required > communications link does not exist with the current technologies available > in the PC environment, and the processing power is also beyond the > capabilities of PC-type computers. But, theoretically, it is possible. > > 73, Ray, K9DUR Actually this is not too difficult. If you have an ADC capable of digitizing 0-50 MHz, and enough RAM connected to it to store a block of data, say 8192 samples, then it is possible to display any bandwidth on the panadapter from 0 - 50 MHz. This data needs to be sent separately from the real time demodulated data stream, but since an update rate of 20 - 30 frames per second is enough to make the panadapter look "real time" to the human eye, the bandwidth required to send this data is reduced by a very large amount. You cannot concatenate the 8192 sample blocks into a larger block to increase spectral resolution, though, since only the samples in each block are contiguous - from block to block they are not. The spectral resolution you get is dependent then on the storage size of the RAM connected to the ADC. You can apply averaging to the blocks though. You can get much larger blocks by increasing the storage size of a block. This is how QS1R and SDRMAX2/3 are capable of displaying any bandwidth from 0 - 50 MHz on the panadapter and switching between them on the fly. Regards, -- Phil Covington Software Radio Laboratory LLC Columbus, Ohio http://www.srl-llc.com ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
Yep, that's the idea -- except the little boxes at the top should be blue and somewhat larger (Flex-3000s). And of course the real issue is what the software is doing to make all the hardware act synergistically. Software doesn't like to be photographed. I just recently discovered CW Skimmer and it's on my to-do list. Found PSK31 software first. SDRs open up a new world of possibilities. Maybe instead of a panadaptor display, we'll eventually be viewing QSO-displays like Skimmer's or WinWarbler's instead of spectrum images. Long ago, I was project leader on a university research team to try to develop a system that could not only decode, but also *participate* in Morse communications. When I moved on, it was working pretty well -- could decode the interactions on a CW traffic net (I worked EPA and occasionally 3RN traffic nets back then, so I was the "expert" driving the computer's "expert system" software design). The system we built could not only decode the transmissions, but actually understand things like stations being sent "down 10", follow them down the band, find them in QRM, follow the traffic exchange, and then get back to the net frequency when they finished. The computer, which occupied most of a floor of the building, wasn't quite fast enough though to be a participant in a net, or to understand more than one signal at a time. Kind of like most human operators. The project continued though, but I lost track of it. Lots of fun. That was in 1975 or so - 30+ years ago! The hardware required was a PDP-11 and PDP-10, plus some front-end DSP and analog stuff we designed and the only radio we could find at the time with a computer-friendly control interface - a 651S-1. Speaker audio came in through an A/D since there was no other way to get the signal out of the radio. Control was over the digital port. Also this was a good excuse to put a TH6DXX on top of a 30-foot tower, which was on top of a ten-story building! And then I changed jobs a month or two later. Grmph. Sadly, no pictures to show. There are some old papers available, e.g., see http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADP003800 I have a yellowed hard-copy I can scan if anybody's curious. Back in the 70s, a ham could have (did) put together such a "Skimmer 0.0001" for a mere few million dollars. Probably $20 million in today's currency. "Honey, I really need a new radio"? Naah, better wait a bit for the price to drop. Today, my Flex-3000 and $200 PC are far more powerful than that 1975 setup. ... Maybe I'll get back to writing a little code Or maybe it's already been written and I just have to find it out there. So many toys...etc etc etc 73, /Jack On Fri, 2009-06-19 at 12:55 -0700, k...@vhfdx.com wrote: > You mean like this? > > http://www.k3lr.com/skimmer/ > > > At 07:45 PM 6/19/2009 +, Jack Haverty wrote: > >We could do some thinking "outside the box" > > > >You can only make a single machine, or a single component like an A/D so > >fast. As you approach that limit, cost goes way up, so it becomes too > >expensive to get to the limit. > > > >A neat feature of the Flex approach is the architecture, especially the > >modularity. RF gets handled in the Flex. Digital stuff gets handled by > >a PC. The software does magic that formerly needed extra hardware. You > >can add more components - PCs or software - to do things like remote > >operation across a LAN or Internet, or using separate computers for > >logging, digital-mode processing, etc. > > > >The overall "radio" is all of these things connected together, operating > >synergistically. It's just not all inside one little metal box like > >other old-technology radios. > > > >My background is in computers and networking. When computers weren't > >fast enough, we simply added more computers, linked together > >appropriately through some kind of network. If you look at the > >equipment room for any of the major websites, you'll probably see many > >19" racks, with each rack containing maybe a dozen standard PC-like > >machines. Viewed from the outside, they all look like one big, fast > >machine, but a lot cheaper to put together than one big fast machine, > >which you probably can't buy anyway. > > > >Now, ... imagine a rack containing say ten or so Flex-3000s, each > >connected to its own standard rack-mounted PC. Each Flex would handle > >say 40 kHz of spectrum. The spectrum data stream - the data points that > >create the actual panadaptor display, maybe 1000 data points about 15-20 > >times a second? - from each Flex is sent to yet another computer - the > >"control head". A PowerSDR version would be needed in each Flex-3000's > >associated PC to make that data stream externally accessible to the > >control head PC over CAT or Ethernet or whatever. Current Flex-3000s > >and current PCs would work fine. You just need a bunch of them. > > > >The Control Head would need a modified versio
Re: [Flexradio] mobile sdr and a complete spectrum display
You mean like this? http://www.k3lr.com/skimmer/ At 07:45 PM 6/19/2009 +, Jack Haverty wrote: We could do some thinking "outside the box" You can only make a single machine, or a single component like an A/D so fast. As you approach that limit, cost goes way up, so it becomes too expensive to get to the limit. A neat feature of the Flex approach is the architecture, especially the modularity. RF gets handled in the Flex. Digital stuff gets handled by a PC. The software does magic that formerly needed extra hardware. You can add more components - PCs or software - to do things like remote operation across a LAN or Internet, or using separate computers for logging, digital-mode processing, etc. The overall "radio" is all of these things connected together, operating synergistically. It's just not all inside one little metal box like other old-technology radios. My background is in computers and networking. When computers weren't fast enough, we simply added more computers, linked together appropriately through some kind of network. If you look at the equipment room for any of the major websites, you'll probably see many 19" racks, with each rack containing maybe a dozen standard PC-like machines. Viewed from the outside, they all look like one big, fast machine, but a lot cheaper to put together than one big fast machine, which you probably can't buy anyway. Now, ... imagine a rack containing say ten or so Flex-3000s, each connected to its own standard rack-mounted PC. Each Flex would handle say 40 kHz of spectrum. The spectrum data stream - the data points that create the actual panadaptor display, maybe 1000 data points about 15-20 times a second? - from each Flex is sent to yet another computer - the "control head". A PowerSDR version would be needed in each Flex-3000's associated PC to make that data stream externally accessible to the control head PC over CAT or Ethernet or whatever. Current Flex-3000s and current PCs would work fine. You just need a bunch of them. The Control Head would need a modified version of PowerSDR, that could control 10 Flexes simultaneously, and keep them all on the proper frequencies. It would also aggregate the data streams, and create the spectrum display to cover 10x40kHz or 400 kHz of whatever band is of interest. If you need more than that, just get another rack with 10 more Flex-3000s. Wow, in digital modes, you could even simultaneously decode all CW or PSK or RTTY activity on the whole band! Hmmm, how about all those transmitters in those Flex-3000s... Hey, you could even carry on multiple QSOs (some antenna wizardry required). Field Day? November SS? The mind boggles. Personally, I have trouble keeping track of what's happening in 40kHz of spectrum. But if you wanted band-wide capability, it could be done...with today's hardware. Not sure about that hundred-foot monitor though. The point? Just to say that the Flex architecture opens up a whole new world and ways of doing things. SDR is cool because it leverages the technologies of hardware and computer software. Networked SDR, which is only beginning to exist (com2tcp and such), opens up yet another new world. Dual-core? Quad-core? 2nd RX? Hah! Hope we'll see somebody put together a rack of Flex-3000s! For the "ultimate station" crowd, I bet this would cost way less than some of those stacked-beam array farms you see on QST covers now and then. This would be a very cool demo - maybe with the "new architecture" software. 73, /Jack K3FIV (who has always been accused of thinking way outside the box) On Fri, 2009-06-19 at 09:04 -0400, Ray Andrews, K9DUR wrote: > Jim, > > You wrote, "...is it a limitation of current components that prevents having > a panadapter that can display the entire band at once?" > > The short answer to your question is "Yes". > > The amount of spectrum that can be monitored at one time is determined by > the maximum bandwidth of the A/D convertor which is in turn dependent on the > sampling rate used. The maximum bandwidth is always going to be less than > the sampling rate. Therefore, the frequency range displayed by the > panadapter is determined by the capabilities of the A/D convertor used. You > will notice that the FLEX-5000 family of transceivers is capable of using a > sampling rate of 192 kHz while the FLEX-3000 is only capable of a maximum > sampling rate of 96 kHz. This difference is due to the different A/D chips > used in the 2 types of radios. > > Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, > a communications link with the bandwidth neseccary to handle the resulting > data stream, and the CPU power required to process that 40 MHz bandwidth > digital stream in real time, it would be possible to display the entire HF > spectrum at one time. Of course, you would also need a monitor a couple of > hundred feet wide to make the display useablehi..hi. Seriously, an A/D > with t
Re: [Flexradio] mobile sdr and a complete spectrum display
We could do some thinking "outside the box" You can only make a single machine, or a single component like an A/D so fast. As you approach that limit, cost goes way up, so it becomes too expensive to get to the limit. A neat feature of the Flex approach is the architecture, especially the modularity. RF gets handled in the Flex. Digital stuff gets handled by a PC. The software does magic that formerly needed extra hardware. You can add more components - PCs or software - to do things like remote operation across a LAN or Internet, or using separate computers for logging, digital-mode processing, etc. The overall "radio" is all of these things connected together, operating synergistically. It's just not all inside one little metal box like other old-technology radios. My background is in computers and networking. When computers weren't fast enough, we simply added more computers, linked together appropriately through some kind of network. If you look at the equipment room for any of the major websites, you'll probably see many 19" racks, with each rack containing maybe a dozen standard PC-like machines. Viewed from the outside, they all look like one big, fast machine, but a lot cheaper to put together than one big fast machine, which you probably can't buy anyway. Now, ... imagine a rack containing say ten or so Flex-3000s, each connected to its own standard rack-mounted PC. Each Flex would handle say 40 kHz of spectrum. The spectrum data stream - the data points that create the actual panadaptor display, maybe 1000 data points about 15-20 times a second? - from each Flex is sent to yet another computer - the "control head". A PowerSDR version would be needed in each Flex-3000's associated PC to make that data stream externally accessible to the control head PC over CAT or Ethernet or whatever. Current Flex-3000s and current PCs would work fine. You just need a bunch of them. The Control Head would need a modified version of PowerSDR, that could control 10 Flexes simultaneously, and keep them all on the proper frequencies. It would also aggregate the data streams, and create the spectrum display to cover 10x40kHz or 400 kHz of whatever band is of interest. If you need more than that, just get another rack with 10 more Flex-3000s. Wow, in digital modes, you could even simultaneously decode all CW or PSK or RTTY activity on the whole band! Hmmm, how about all those transmitters in those Flex-3000s... Hey, you could even carry on multiple QSOs (some antenna wizardry required). Field Day? November SS? The mind boggles. Personally, I have trouble keeping track of what's happening in 40kHz of spectrum. But if you wanted band-wide capability, it could be done...with today's hardware. Not sure about that hundred-foot monitor though. The point? Just to say that the Flex architecture opens up a whole new world and ways of doing things. SDR is cool because it leverages the technologies of hardware and computer software. Networked SDR, which is only beginning to exist (com2tcp and such), opens up yet another new world. Dual-core? Quad-core? 2nd RX? Hah! Hope we'll see somebody put together a rack of Flex-3000s! For the "ultimate station" crowd, I bet this would cost way less than some of those stacked-beam array farms you see on QST covers now and then. This would be a very cool demo - maybe with the "new architecture" software. 73, /Jack K3FIV (who has always been accused of thinking way outside the box) On Fri, 2009-06-19 at 09:04 -0400, Ray Andrews, K9DUR wrote: > Jim, > > You wrote, "...is it a limitation of current components that prevents having > a panadapter that can display the entire band at once?" > > The short answer to your question is "Yes". > > The amount of spectrum that can be monitored at one time is determined by > the maximum bandwidth of the A/D convertor which is in turn dependent on the > sampling rate used. The maximum bandwidth is always going to be less than > the sampling rate. Therefore, the frequency range displayed by the > panadapter is determined by the capabilities of the A/D convertor used. You > will notice that the FLEX-5000 family of transceivers is capable of using a > sampling rate of 192 kHz while the FLEX-3000 is only capable of a maximum > sampling rate of 96 kHz. This difference is due to the different A/D chips > used in the 2 types of radios. > > Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, > a communications link with the bandwidth neseccary to handle the resulting > data stream, and the CPU power required to process that 40 MHz bandwidth > digital stream in real time, it would be possible to display the entire HF > spectrum at one time. Of course, you would also need a monitor a couple of > hundred feet wide to make the display useablehi..hi. Seriously, an A/D > with these capabilities would be prohibitively expensive, the required > communications link does not exist w
Re: [Flexradio] mobile sdr and a complete spectrum display
CORRECTION - I misstated this really badly. Lower sampling rates provide sharper filters - DUH!. I need another pot of coffee. My bad. -Tim -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Tim Ellison Sent: Friday, June 19, 2009 10:41 AM To: Ray Andrews, K9DUR; 'Philip Covington' Cc: flexradio@flex-radio.biz; 'Jim' Subject: Re: [Flexradio] mobile sdr and a complete spectrum display I actually use 192 KHz to get the sharpest RX filter skirts, but zoom in the console so it looks like 96K for the exact reason you stated - better visual spectral resolution. -Tim -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Ray Andrews, K9DUR Sent: Friday, June 19, 2009 10:35 AM To: 'Philip Covington' Cc: flexradio@flex-radio.biz; 'Jim' Subject: Re: [Flexradio] mobile sdr and a complete spectrum display Phil, I virtually never use the 192 kHz sample rate for the same reasons you listed. My radio is "glued" to 96 kHz. 73, Ray, K9DUR ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
Here is a link about a very interesting research project that has crafted an rf processing system that covers 600mhz to 8Ghz by modeling the human ear. Not exactly in our frequency neighborhood and of course still in the research lab, but perhaps someday... http://ieeexplore.ieee.org/search/wrapper.jsp?arnumber=4982879 -Original Message- From: Ray Andrews, K9DUR [mailto:k9...@rnacs.com] Sent: Friday, June 19, 2009 6:04 AM To: 'Jim'; flexradio@flex-radio.biz Subject: RE: [Flexradio] mobile sdr and a complete spectrum display Jim, You wrote, "...is it a limitation of current components that prevents having a panadapter that can display the entire band at once?" The short answer to your question is "Yes". The amount of spectrum that can be monitored at one time is determined by the maximum bandwidth of the A/D convertor which is in turn dependent on the sampling rate used. The maximum bandwidth is always going to be less than the sampling rate. Therefore, the frequency range displayed by the panadapter is determined by the capabilities of the A/D convertor used. You will notice that the FLEX-5000 family of transceivers is capable of using a sampling rate of 192 kHz while the FLEX-3000 is only capable of a maximum sampling rate of 96 kHz. This difference is due to the different A/D chips used in the 2 types of radios. Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, a communications link with the bandwidth neseccary to handle the resulting data stream, and the CPU power required to process that 40 MHz bandwidth digital stream in real time, it would be possible to display the entire HF spectrum at one time. Of course, you would also need a monitor a couple of hundred feet wide to make the display useablehi..hi. Seriously, an A/D with these capabilities would be prohibitively expensive, the required communications link does not exist with the current technologies available in the PC environment, and the processing power is also beyond the capabilities of PC-type computers. But, theoretically, it is possible. 73, Ray, K9DUR ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
I actually use 192 KHz to get the sharpest RX filter skirts, but zoom in the console so it looks like 96K for the exact reason you stated - better visual spectral resolution. -Tim -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Ray Andrews, K9DUR Sent: Friday, June 19, 2009 10:35 AM To: 'Philip Covington' Cc: flexradio@flex-radio.biz; 'Jim' Subject: Re: [Flexradio] mobile sdr and a complete spectrum display Phil, I virtually never use the 192 kHz sample rate for the same reasons you listed. My radio is "glued" to 96 kHz. 73, Ray, K9DUR ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
Phil, I virtually never use the 192 kHz sample rate for the same reasons you listed. My radio is "glued" to 96 kHz. 73, Ray, K9DUR ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
On Fri, Jun 19, 2009 at 9:22 AM, Philip Covington wrote: > On Fri, Jun 19, 2009 at 9:04 AM, Ray Andrews, K9DUR wrote: > >> Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, >> a communications link with the bandwidth neseccary to handle the resulting >> data stream, and the CPU power required to process that 40 MHz bandwidth >> digital stream in real time, it would be possible to display the entire HF >> spectrum at one time. Of course, you would also need a monitor a couple of >> hundred feet wide to make the display useablehi..hi. Seriously, an A/D >> with these capabilities would be prohibitively expensive, the required >> communications link does not exist with the current technologies available >> in the PC environment, and the processing power is also beyond the >> capabilities of PC-type computers. But, theoretically, it is possible. >> >> 73, Ray, K9DUR > > Actually this is not too difficult. If you have an ADC capable of > digitizing 0-50 MHz, and enough RAM connected to it to store a block > of data, say 8192 samples, then it is possible to display any > bandwidth on the panadapter from 0 - 50 MHz. This data needs to be > sent separately from the real time demodulated data stream, but since > an update rate of 20 - 30 frames per second is enough to make the > panadapter look "real time" to the human eye, the bandwidth required > to send this data is reduced by a very large amount. You cannot > concatenate the 8192 sample blocks into a larger block to increase > spectral resolution, though, since only the samples in each block are > contiguous - from block to block they are not. The spectral > resolution you get is dependent then on the storage size of the RAM > connected to the ADC. You can apply averaging to the blocks though. > You can get much larger blocks by increasing the storage size of a > block. This is how QS1R and SDRMAX2/3 are capable of displaying any > bandwidth from 0 - 50 MHz on the panadapter and switching between them > on the fly. > > Regards, > -- > Phil Covington > Software Radio Laboratory LLC > Columbus, Ohio > http://www.srl-llc.com > Given the above capability to display a very wide spectrum, operating from day to day I find myself staying below 200 - 250 kHz bandwidth on the panadapter. Anything above 200 kHz ( or 192 kHz) is more difficult to use with "point and click tuning". Most of the time I stay at 100 kHz (or 96 kHz) bandwidth on the panadapter for general looking around the bands. The other thing to consider is that the narrower the bandwidth of the panadapter, the weaker signals you can see. 73 Phil N8VB ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
It isn't a feature upgrade. They are two completely different hardware architectures. Maybe a future radio design. -Tim -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Jim Sent: Friday, June 19, 2009 9:41 AM To: flexradio@flex-radio.biz Subject: Re: [Flexradio] mobile sdr and a complete spectrum display Sounds like a future feature request to me.. Jim, WD7R -Original Message- From: Philip Covington [mailto:p.coving...@gmail.com] Sent: Friday, June 19, 2009 6:22 AM To: Ray Andrews, K9DUR Cc: Jim; flexradio@flex-radio.biz Subject: Re: [Flexradio] mobile sdr and a complete spectrum display On Fri, Jun 19, 2009 at 9:04 AM, Ray Andrews, K9DUR wrote: > Theoretically, if you had an A/D capable of a sampling rate of 40 MHz > or so, > a communications link with the bandwidth neseccary to handle the > resulting data stream, and the CPU power required to process that 40 > MHz bandwidth digital stream in real time, it would be possible to > display the entire HF spectrum at one time. Of course, you would also > need a monitor a couple of > hundred feet wide to make the display useablehi..hi. Seriously, > an A/D > with these capabilities would be prohibitively expensive, the required > communications link does not exist with the current technologies > available in the PC environment, and the processing power is also > beyond the capabilities of PC-type computers. But, theoretically, it is > possible. > > 73, Ray, K9DUR Actually this is not too difficult. If you have an ADC capable of digitizing 0-50 MHz, and enough RAM connected to it to store a block of data, say 8192 samples, then it is possible to display any bandwidth on the panadapter from 0 - 50 MHz. This data needs to be sent separately from the real time demodulated data stream, but since an update rate of 20 - 30 frames per second is enough to make the panadapter look "real time" to the human eye, the bandwidth required to send this data is reduced by a very large amount. You cannot concatenate the 8192 sample blocks into a larger block to increase spectral resolution, though, since only the samples in each block are contiguous - from block to block they are not. The spectral resolution you get is dependent then on the storage size of the RAM connected to the ADC. You can apply averaging to the blocks though. You can get much larger blocks by increasing the storage size of a block. This is how QS1R and SDRMAX2/3 are capable of displaying any bandwidth from 0 - 50 MHz on the panadapter and switching between them on the fly. Regards, -- Phil Covington Software Radio Laboratory LLC Columbus, Ohio http://www.srl-llc.com ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
Sounds like a future feature request to me.. Jim, WD7R -Original Message- From: Philip Covington [mailto:p.coving...@gmail.com] Sent: Friday, June 19, 2009 6:22 AM To: Ray Andrews, K9DUR Cc: Jim; flexradio@flex-radio.biz Subject: Re: [Flexradio] mobile sdr and a complete spectrum display On Fri, Jun 19, 2009 at 9:04 AM, Ray Andrews, K9DUR wrote: > Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, > a communications link with the bandwidth neseccary to handle the resulting > data stream, and the CPU power required to process that 40 MHz bandwidth > digital stream in real time, it would be possible to display the entire HF > spectrum at one time. Of course, you would also need a monitor a couple of > hundred feet wide to make the display useablehi..hi. Seriously, an A/D > with these capabilities would be prohibitively expensive, the required > communications link does not exist with the current technologies available > in the PC environment, and the processing power is also beyond the > capabilities of PC-type computers. But, theoretically, it is possible. > > 73, Ray, K9DUR Actually this is not too difficult. If you have an ADC capable of digitizing 0-50 MHz, and enough RAM connected to it to store a block of data, say 8192 samples, then it is possible to display any bandwidth on the panadapter from 0 - 50 MHz. This data needs to be sent separately from the real time demodulated data stream, but since an update rate of 20 - 30 frames per second is enough to make the panadapter look "real time" to the human eye, the bandwidth required to send this data is reduced by a very large amount. You cannot concatenate the 8192 sample blocks into a larger block to increase spectral resolution, though, since only the samples in each block are contiguous - from block to block they are not. The spectral resolution you get is dependent then on the storage size of the RAM connected to the ADC. You can apply averaging to the blocks though. You can get much larger blocks by increasing the storage size of a block. This is how QS1R and SDRMAX2/3 are capable of displaying any bandwidth from 0 - 50 MHz on the panadapter and switching between them on the fly. Regards, -- Phil Covington Software Radio Laboratory LLC Columbus, Ohio http://www.srl-llc.com ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
On Fri, Jun 19, 2009 at 9:04 AM, Ray Andrews, K9DUR wrote: > Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, > a communications link with the bandwidth neseccary to handle the resulting > data stream, and the CPU power required to process that 40 MHz bandwidth > digital stream in real time, it would be possible to display the entire HF > spectrum at one time. Of course, you would also need a monitor a couple of > hundred feet wide to make the display useablehi..hi. Seriously, an A/D > with these capabilities would be prohibitively expensive, the required > communications link does not exist with the current technologies available > in the PC environment, and the processing power is also beyond the > capabilities of PC-type computers. But, theoretically, it is possible. > > 73, Ray, K9DUR Actually this is not too difficult. If you have an ADC capable of digitizing 0-50 MHz, and enough RAM connected to it to store a block of data, say 8192 samples, then it is possible to display any bandwidth on the panadapter from 0 - 50 MHz. This data needs to be sent separately from the real time demodulated data stream, but since an update rate of 20 - 30 frames per second is enough to make the panadapter look "real time" to the human eye, the bandwidth required to send this data is reduced by a very large amount. You cannot concatenate the 8192 sample blocks into a larger block to increase spectral resolution, though, since only the samples in each block are contiguous - from block to block they are not. The spectral resolution you get is dependent then on the storage size of the RAM connected to the ADC. You can apply averaging to the blocks though. You can get much larger blocks by increasing the storage size of a block. This is how QS1R and SDRMAX2/3 are capable of displaying any bandwidth from 0 - 50 MHz on the panadapter and switching between them on the fly. Regards, -- Phil Covington Software Radio Laboratory LLC Columbus, Ohio http://www.srl-llc.com ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
Jim, You wrote, "...is it a limitation of current components that prevents having a panadapter that can display the entire band at once?" The short answer to your question is "Yes". The amount of spectrum that can be monitored at one time is determined by the maximum bandwidth of the A/D convertor which is in turn dependent on the sampling rate used. The maximum bandwidth is always going to be less than the sampling rate. Therefore, the frequency range displayed by the panadapter is determined by the capabilities of the A/D convertor used. You will notice that the FLEX-5000 family of transceivers is capable of using a sampling rate of 192 kHz while the FLEX-3000 is only capable of a maximum sampling rate of 96 kHz. This difference is due to the different A/D chips used in the 2 types of radios. Theoretically, if you had an A/D capable of a sampling rate of 40 MHz or so, a communications link with the bandwidth neseccary to handle the resulting data stream, and the CPU power required to process that 40 MHz bandwidth digital stream in real time, it would be possible to display the entire HF spectrum at one time. Of course, you would also need a monitor a couple of hundred feet wide to make the display useablehi..hi. Seriously, an A/D with these capabilities would be prohibitively expensive, the required communications link does not exist with the current technologies available in the PC environment, and the processing power is also beyond the capabilities of PC-type computers. But, theoretically, it is possible. 73, Ray, K9DUR ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
I've done remote using my jailbroken Ipod Tough 2nd generation. There are some commercial portable radios on the market claiming to be "software defined". The Thales Liberty is one that comes to mind. Dave wo2x - Original Message - From: "Tim Ellison" To: "Jim" ; Sent: Friday, June 19, 2009 7:42 AM Subject: Re: [Flexradio] mobile sdr and a complete spectrum display And many people are running PowerSDR remote on small tablet type computers and I have heard of one doing it on a modified iPhone (unlocked so that two applications can run at the same time; VNC and Skype). -Tim -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Jim Sent: Friday, June 19, 2009 12:47 AM To: flexradio@flex-radio.biz Subject: [Flexradio] mobile sdr and a complete spectrum display Well, just to stir things up a bit - I find sdr technology so compelling that I'm yearning for it to appear in handheld and mobile radios. Any thoughts on if/when this might happen and what form that might take? Also, for the current generation of flex radios - the 5000 and 3000, is it a limitation of current components that prevents having a panadapter that can display the entire band at once? 73's WD7W Jim ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
Re: [Flexradio] mobile sdr and a complete spectrum display
Also, for the current generation of flex radios - the 5000 and 3000, is it a limitation of current components that prevents having a panadapter that can display the entire band at once? Actually, the bandwidth is bound by the A/D sampling rate. FlexRadio uses a different RF conversion to bits architecture than the other receiver only SDRs. And many people are running PowerSDR remote on small tablet type computers and I have heard of one doing it on a modified iPhone (unlocked so that two applications can run at the same time; VNC and Skype). -Tim -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Jim Sent: Friday, June 19, 2009 12:47 AM To: flexradio@flex-radio.biz Subject: [Flexradio] mobile sdr and a complete spectrum display Well, just to stir things up a bit - I find sdr technology so compelling that I'm yearning for it to appear in handheld and mobile radios. Any thoughts on if/when this might happen and what form that might take? Also, for the current generation of flex radios - the 5000 and 3000, is it a limitation of current components that prevents having a panadapter that can display the entire band at once? 73's WD7W Jim ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
