My idea for a KerberosSDR #2 iteration

Discuss KerberosSDR - 4x Coherent RTL-SDR
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alexxmarsh8888
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My idea for a KerberosSDR #2 iteration

Post by alexxmarsh8888 » Sun Sep 13, 2020 6:42 am

I was thinking about tracking frequencies outside of the range of the kerberossdr. I am thoroughly in love with the kerberossdr as a whole. The product, the software, and everything about it as it works seamlessly and I am dying to see another kerberossdr. I thought maybe you could try doing the same idea as kerberossdr but with hackrf receivers that could cover a much larger frequency range. I know about opera cake which is the hackrf's antenna switcher which can do direction finding. It however lacks any dedicated software and they are impossible to buy so you have to make em yourself as they are open source. I also think that the 4 receiver technique is much better and more reliable albeit a bit more expensive. I would love to see you guys release a new kerberos using this idea and even upgrade the radar side of it by possible hitting up an active radar beacon with an amplifier system and transmitted pulses and use it maybe for drone radar. I have a ton of ideas and even some drawings I would love to show you. I will also offer my assistance (wishful thinking) in any way I can like possibly graphic design as I am pretty ok at that. I have a few more ideas for this too. You can contact me here on the forum and ill be happy to give you a more in depth description of my ideas as well as some drawings I made. I would also love a pc version of the android app that you can print out a rundown of the tracking and save the files with the graphic representation for archiving signals tracked. It would be amazing to also add support for gps dongles on the pc or add a built in gps module to the kerberos setup to make it seamless on the pc. There are a lot of signals above 2ghz I am dying to track so this would be a dream come true for me... no joke lol.

Would love to hear what any of you think of this idea too and ideas about how feasible it might be.

rtlsdrblog
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Re: My idea for a KerberosSDR #2 iteration

Post by rtlsdrblog » Thu Sep 17, 2020 5:00 am

Thanks, we are thinking about higher end models for the future, but it is difficult once you start to go past RTL-SDRs as the basis. The challenges is that 4x HackRF's would be 4X the HackRF BOM cost. Even if that's $50 only per unit, that's $200 just for the BOM. Then add in the hw engineering costs + prototyping costs + new SW + firmware + drivers dev costs + distribution, we're already looking at more than $500 per unit.

Stage 1 was to get KerberosSDR out there and working. Stage 2 we're currently working on improving the current hardware and software to make the whole system easier and more accurate to use. At stage 2 hopefully we can get some commercial customers and actually make a profit.

Stage 3 we'll use those profits to investigate how to make a wider band version and/or more interesting applications.

SIGINT
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Re: My idea for a KerberosSDR #2 iteration

Post by SIGINT » Thu Sep 17, 2020 8:03 pm

A few suggestions for future releases:
- Replace those flimsy micro USB connectors - preferably with 2 x USB-C. If we can not find a non PD USB-C charger, it is just a matter of using a USB-A to USB-C cable. Include a couple in the package if possible -and adjust the price.
- 6 x SDR would likely improve accuracy ?
- IF we can not get internal switches (preferred) to disconnect the antennas during sync - use BNC adapters.
- Re-orient the antenna sockets, antenna 4 is way to close to those fragile Micro USB connectors, hard not to touch the USB cable when working with the antennas.
- Status LED's or even a Raspberry Pi mini display giving us a status and perpahs - if possible - advising if time to re-sync (which I would love if it could automate).
- Antenna connectors and LED's etc. on opposite side from the USB connectors. Gives a cleaner front if KSDR is mounted in a rack type cabinet along with Raspberry Pi's etc. I imagine a cabinet with 1 x KSDR and 3 x Pi's - 2 for KSDR processing and one running an SDR app connected to a mini HDMI monitor. Good for finding/monitoring signals, judging how much gain is needed. Like to have all the cable infrastructure hidden in the cabinet.

rtlsdrblog
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Re: My idea for a KerberosSDR #2 iteration

Post by rtlsdrblog » Sun Sep 20, 2020 12:15 am

A few suggestions for future releases:
- Replace those flimsy micro USB connectors - preferably with 2 x USB-C. If we can not find a non PD USB-C charger, it is just a matter of using a USB-A to USB-C cable. Include a couple in the package if possible -and adjust the price.

Yep V2 will be all USB-C. We did use basic USB-C in V1 batch 1 for the power connector but we ended up with a large number of complaints from confused users who had bought PD chargers instead of our recommendation of a standard 5V charger + USB-C cable.

V2 will implement USB-C PD switching to 5V correctly as we've upgraded the PCB manufacturing tech and can now implement that circuit.


- 6 x SDR would likely improve accuracy ?

5x would probably be enough for more serious work as compared to 4x in terms of ambiguity resolution. 6x wouldn't be much difference from 5x I think.

- IF we can not get internal switches (preferred) to disconnect the antennas during sync - use BNC adapters.

V2 will have switches tested to work and not introduce phase distortion, so no problems there.

- Re-orient the antenna sockets, antenna 4 is way to close to those fragile Micro USB connectors, hard not to touch the USB cable when working with the antennas.

We'll be paying attention to this.

- Status LED's or even a Raspberry Pi mini display giving us a status and perpahs - if possible - advising if time to re-sync (which I would love if it could automate).

The new code that's ready soon will be able to monitor sync automatically (with V2 hardware)

- Antenna connectors and LED's etc. on opposite side from the USB connectors. Gives a cleaner front if KSDR is mounted in a rack type cabinet along with Raspberry Pi's etc. I imagine a cabinet with 1 x KSDR and 3 x Pi's - 2 for KSDR processing and one running an SDR app connected to a mini HDMI monitor. Good for finding/monitoring signals, judging how much gain is needed. Like to have all the cable infrastructure hidden in the cabinet.

Not sure if the PCB layout restrictions will allow for that but we'll see. Some RF traces need specific routing which makes the layout tricky. For rack mount, isn't it better if all connectors are on one side?

SIGINT
Posts: 13
Joined: Wed Oct 19, 2016 10:19 pm

Re: My idea for a KerberosSDR #2 iteration

Post by SIGINT » Sun Sep 20, 2020 7:15 pm

"Not sure if the PCB layout restrictions will allow for that but we'll see. Some RF traces need specific routing which makes the layout tricky. For rack mount, isn't it better if all connectors are on one side?"

First - would a shielded, internal cable moving the antenna connectors to the other side of the chassis compromise accuracy ? - the cables between the antennas and the antenna will just be an extension of these ?

Regarding rack mounting. Think selling this to agencies/organisations (or me) who would like to build a self contained chassis with perhaps:
-1 x KSDR
-3 x Raspberry Pi (As you suggest using two Pi's in the future to divide load) Final Pi for singnals monitoring with an SDR / -Waterfall display.
-Power supply for the above
-A compact HDMI monitor for the SDR app + web client for the KSDR.

Antennas may need to be changed when switching between UHF and VHF triangulation. So these connectors should be accessible.

Ideally, we never need to touch the USB cables connecting the devices, power input (if not for the lack of power button on the Pi) - so the internal piping should be inside the chassis for the combined setup.

Oh regarding USB cables: My Pi 4 will NOT boot if the USB cable to the KSDR is attached. Black screen, no video. If I remove it untill I see the raspberries on the screen - then re-attach the cables, it works fine.

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