On 01/01/2024 20:28, Jeff Long wrote:
The term "doppler" tends to imply in many engineer's minds some type of actual physicality...The problem here is relating this kind of chirp to anything physical. As Daniel says, this may make sense for a synthesized signal. It's pretty easy to create any signal you want using some combination of Python and GNU Radio (or other tools). One possible problem could be specifying very large numbers for parameters in some programs.
On Mon, Jan 1, 2024 at 7:40 PM Marcus D. Leech <patchvonbraun@gmail.com> wrote:
On 01/01/2024 16:11, Marcus Müller wrote:
C/15 is actually about *twice* as fast as the fastest object we will ever have made.Liya,
Doppler shift Δf is proportional to both speed and carrier frequency f₀
Δf = f₀ · v/c₀,
where v is the relative speed of your thing, and c₀ is the speed of light.
The highest frequencies we can, so far, do radio communications on, are in the range of f₀=150 GHz.
So, assuming you do communications on 150 GHz, for your Doppler shift to be Δf=10 GHz higher after 1s, your acceleration must been
a = Δf / f₀ · c₀ / 1s = 10 GHz / 150 GHz · 3·10⁸ m/s / s = 2/30 · 3·10⁸ m/s² = 1/15 c₀/s.
The fastest object mankind has ever built is the Parker Solar Probe, which will burn up while it spirals into the sun, at a maximum velocity of ca 1/15 of the speed of light. It takes it years to reach that speed, not 1s.
So, you're assuming you're seeing a doppler from a satellite rotating around earth that sees a relative acceleration higher than a "satellite" around the sun actively being pulled into the sun by the sun's immense gravity.
That sadly makes no physical sense!
Best regards,
Marcus
On 01.01.24 07:51, Jiya Johnson wrote:
Yes I want to use 10GHz/s
On Sat, Dec 30, 2023, 4:05 PM Jiya Johnson <jiyajohnson10@gmail.com> wrote:
Greetings everyone,I went through these grc files and tried to do drift_simulation, i am not getting the way to get 10GHz/s using inspectrum and frequency sink slope calculation i have attached the grc and screenshots.
