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Solved Noise generator functionality , and big update , adding many pictures and explanations.

Brumi-2021 2023-04-30 21:41:09 +02:00
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Signal-Generator.md

@ -5,7 +5,18 @@ The signal generator found under Utilities can be used to generate a carrier whi
* sawtooth up * sawtooth up
* sawtooth down * sawtooth down
* square * square
* noise : does not appear to function * noise n x 20khz
* noise n x 10khz
* noise n x 5khz
## * Sine / Triangle / Sawtooth up / Sawtooth down / Square
We can select the periodic signal to modulate the carrier , in FM .(and we can adjust below the delta FM deviation)
![image](https://user-images.githubusercontent.com/86470699/235372191-87eeac6f-e9b1-4cf5-a060-96d1965587a7.png)
![image](https://user-images.githubusercontent.com/86470699/235372207-fe2eb3d1-8171-47ad-8e2d-56f0f1a45d59.png)
![image](https://user-images.githubusercontent.com/86470699/235372227-7bfee042-70aa-46c8-adad-974a879b4ce9.png)
Tone defines the frequency of modulation. Tone defines the frequency of modulation.
@ -13,3 +24,26 @@ Update when unchecked requires the user to drop carrier, then re-start carrier i
Stop after 1s limits carrier duration to 1 second Stop after 1s limits carrier duration to 1 second
## * White Noise generator options:
From nightly 1st of May 23 fw onwards, we have added 3 White Noise simulation options.
We are generating simulated White Noise ,using pseudo random noise generator, 8 bits linear-feedback shift register (LFSR) algorithm, variant Fibonacci. (Following this wiki [link](https://en.wikipedia.org/wiki/Linear-feedback_shift_register))
* noise n x 20khz, (taps: 6 5; feedback polynomial: x^6 + x^5 + 1 , Periode 63 = 2^n-1,it generates harmonincs aprox every n x 20Khz
* noise n x 10khz (taps: 7 6; feedback polynomial: x^7 + x^6 + 1 , Periode 127 = 2^n-1,it generates harmonincs aprox every n x 10Khz
* noise n x 5khz (taps:8,6,5,4;feedback polynomial: x^8 + x^6 + x^5 + x^4 + 1,Periode 255= 2^n-1, harmonics aprox every n x 5khz
Those GUI title, is indicating that the contents of the FFT spectrum , has harmonics of n x 20khz, or n x 15khz, or n x 10khz.
(so user can select the granularity of the noise harmonics, ideally White noise should have all infinite harmonics) .
Example of the implementation of the first Noise option , n x 20 Khz aprox.
![image](https://user-images.githubusercontent.com/86470699/235372877-9eecb03d-ac05-46d5-be43-858fb8d4d15a.png)
![image](https://user-images.githubusercontent.com/86470699/235372900-7a8603d6-bd55-4f7d-a90e-5e090fba1bcf.png)
Update when unchecked requires the user to drop carrier, then re-start carrier in order for a change of modulation Shape or Tone frequency to take effect. When checked, values will update on the fly.
Stop after 1s limits carrier duration to 1 second