Hi Carlos,
I just realized that maybe the core problem here is that I don't really
understand what you're trying to do --
could you explain what this system will be used for, and why you need
that particular sampling rate etc?
Best regards,
Marcus
On 11/28/2014 05:59 PM, Marcus Müller wrote:
> Hel
Hello Carlos,
I don't really think that what you built really reflects what you're
trying to achieve: I thought you needed a really small delay in time
domain, and a sampling rate conversion from 10MHz to 10.23MHz.
Why are you doing a delay in frequency domain? That will simply be a
frequency shi
Hi Marcus,
I spent a week doing tests and do not know what can be the fault. Did you
see any mistake? [1]
If I transmit the signal with no delay (signal -> FFT -> IFFT -> USRP) I
have a small variable delay unwanted in the receiver.
Greetings.
[1] Now use powers of two in the FFT lenght (128,256
*** The bandwidth of the signal is 4 MHz.
Greetings,
Carlos Alberto Ruiz Naranjo.
Área de Aviónica y Sistemas No Tripulados/Avionics and Unmanned Systems
Department
Parque Tecnológico y Aeronáutico de Andalucía
C/ Wilbur y Orville Wright, 17-19-21
41309 La Rinconada
Sevilla (Spain)
(+34) 95417
Hello!
I have done the fractional delay block ( http://pastebin.com/cEDfTh9m ).
Have you seen some error? I have used the proposed filter in "Closed Form
Variable Fractional Time Delay Using FFT" [1][2]
This is my flowgraph:
- My signal sample rate is 1023 samples per second and I want a
Hi Carlos,
yes, your formular looks correct, scalar multiplication aside.
Regarding your problem:
It's not a problem, it's a feature :)
you're using window functions in your FFT, that's what's changing your
signal.
The FFT is but an implementation of the DFT (discrete fourier
transform), which is,
I have some questions about FFT method.
- I have done a test with my signal ( [Signal] -> [FFT] -> [IFFT] -> [Signal]
) and I have a problem with the spectrum (central lobe):
- To insert a delay I multiply the FFT by [1], right?
Can I insert a delay (no variable) if I multiply the FFT by GN
well, yes, you could, but that sounds ugly:
1. a sample rate of 1e9Hz implies --for complex float-- a memory
consumption of 1e9*8B~=8GB per second...
2. unwieldy fractional resampling, because 10.23e6 and 1e9 don't have a
very large common divisor; you'll be interpolating by a factor of 10
just
Hello,
I have in my project a sample rate of 10.23 million samples per second and
I need to delay the signal +-1ns. With GNURadio block delay I can delay the
signal 97.75ns (1 / 10,230,000 -> + - one sample).
Could I use the fractional resampler block to enter a variable
fractional delay?
Has any
