Scicos Diagram
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Discrete Voltage Controled Oscillator

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Description

This diagram is an open loop model of a discrete Voltage Controled Oscillator.
Regular output voltage can be described with this continous equation :

$\displaystyle y_{s}\left(t\right)=\cos \left[\left(\omega_{0}t\right)+\int^{t}_{0} k_{v} u_{3}\left(\tau\right)+n(\tau)d\tau\right]
$

The noise introduces in the the tunning voltage ist a White Gaussian Noise.
The integral of the input voltage is realized with the EULERINTEGRAL block which use the discrete backward-Euler formula and the VCOEVT block produces the event corresponding to a zero crossing with a discrete method of detection. (cf Modnum block section to learn more).

Context


Fo = 10e6;
To = 1 / Fo;
wo=2*%pi * Fo;
alpha=60e6;
kv=60e6
j_vco=100e6;
N=3;
Nsampl = 80;
Tsampl = To/(Nsampl);
Fsampl = 1 / Tsampl;
Tfin=15*To

Scope Results

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Figure : Input and output voltage of VCO
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Figure : Events generated by the VCOEVT block
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Figure : Events generated by the frequency divider block

Mod_num blocks

See Also

Authors

IRCOM Group Alan Layec