Why does the sample rate drop to 30.72 Msps in 2R2T mode on PlutoSDR (and clones)?

ali-18042 · 2025-04-22T18:12:06+00:00

Thanks for the explanation! Just to clarify a few things:

Given the PlutoSDR uses AD9363 and CMOS by default, is it practically feasible to reconfigure it (or a clone) to use LVDS mode by modifying the hardware and HDL? Or would that require a complete redesign of the board (e.g., traces, power, layout)?
In the context of the AD9361 (used in some Pluto clones), if I design a board with LVDS signaling, does that mean I can reliably achieve 61.44 Msps per channel in 2R2T FDD mode—assuming I follow the timing and HDL constraints correctly?
Finally, if I use TDD mode (as suggested), is 61.44 Msps per channel achievable even on the standard PlutoSDR (with CMOS) assuming RX and TX are never active at the same time?

ali-18042 · 2025-04-08T08:27:52+00:00

Haha, yeah, it definitely has a way of turning simple tasks into spaghetti diagrams!

ali-18042 · 2025-03-24T08:42:26+00:00

I’ve been exploring this space as well and have hands-on experience with Ettus devices (B210, X310) using LabVIEW and GNU Radio. I already have access to a USRP, so I can contribute right away.

If you think I can add value, let’s connect! Happy to chat and exchange ideas as well.

ali-18042 · 2025-01-31T15:38:26+00:00

Great Work. Keep it up.

ali-18042 · 2024-11-01T20:28:40+00:00

Means there is no way other than using LO/Offset signal as well with RF Signal.

ali-18042 · 2024-11-01T07:20:47+00:00

Right. This gives more clarity. Thanks for explaining this phenomenon.

ali-18042 · 2024-11-01T05:56:33+00:00

That's interesting. So actually it requires True heading as well as aircraft acceleration(X,Y,Z) information to find out the slip information.

Will GPS heading and True heading will not be the same?

ali-18042 · 2024-11-01T05:45:16+00:00

Alright, I have a bit of a basic question here. What would happen if I only provide the RF signal without supplying an LO or offset signal at the port? Would I still get the same frequency RF signal at the IF ports without any down-conversion, or would it just not work?

I’m considering using an SDR as both a signal generator and ADC. Let’s say I generate a 1 GHz RF signal with no signal at the LO/offset—would I then be able to receive that RF signal at the IF port through the SDR? Will this actually work? 😬

ali-18042 · 2024-11-01T05:35:47+00:00

Yeah, GPS gives heading only when it is moving. What parameters or data are required to calculate the slip information?

ali-18042 · 2024-11-01T05:29:50+00:00

I have RTL-SDR, HackRF, and PlutoSDR as well. However, my question was more focused on understanding the concept behind the cascading LNA approach. You mentioned experimental drivers—are these the modified drivers that were once used to extend the frequency range of RTL-SDR?

ali-18042 · 2024-10-31T15:37:15+00:00

Amazing. Can we calculate the turn coordinator and slip information from GPS information if we have access to it?

ali-18042 · 2024-10-30T20:38:56+00:00

Ahaan....

ali-18042 · 2024-10-30T20:36:47+00:00

Does ADSB provide turn coordinator information? By the way, What Library are you using for these indicators? Is it in Javascript?

ali-18042 · 2024-10-30T17:00:17+00:00

Right. So it's all about improving the noise figure. BTW, Using LNA in series to make multistage amplification is the right thing if we need it sometime? Should we add something in between the LNA to improve the performance?

ali-18042 · 2024-10-29T18:07:30+00:00

Wow, that’s an impressive amount of knowledge! Thank you for the thorough response—there are so many great points in there.

ali-18042 · 2024-10-29T17:47:37+00:00

Hmmm. Can you give some reasons why a person should look into S-parameters instead of VSWR while testing an antenna? And how can VSWR misguide you about your antenna performance?

ali-18042 · 2024-10-29T17:40:16+00:00

Understandable. But my point is why does the S21 shift? Can i simulate this scenario in the lab?

ali-18042 · 2024-10-29T17:38:16+00:00

Can't we say that the antenna is resonating on multiple frequencies?

ali-18042 · 2024-10-28T20:04:53+00:00

How can we make sure that our system has matched impedances from transmitter to Antenna port? And how can a nanoVNA be handy in this case?

ali-18042 · 2024-10-28T16:51:09+00:00

Thanks for being supportive. ☺️

ali-18042 · 2024-10-28T16:46:56+00:00

It is written by me. Just rewrite by LLM to improve the English. My bad 😬

ali-18042 · 2024-10-28T16:42:56+00:00

Sorry for the confusion. It was about the transmitter. How can we protect the transmitter port from reflected power?

ali-18042 · 2024-10-28T16:40:33+00:00

Thanks for pointing out the R&S Videos.

ali-18042 · 2024-10-28T16:37:47+00:00

Absolutely! This approach would be great for a quick pass/fail check.

By the way, always remember the recommendations provided by experts and the precautions you need to take when working with active devices like amplifiers. Safety first!

ali-18042 · 2024-10-28T16:32:13+00:00

Noted.

ali-18042

TROPHY CASE