Scicos Diagram
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Discrete Voltage Controlled Oscillator

\epsfig{file=discr_vco_diagr.eps,height=10cm}

Module


Contents

Description

This diagram is an open loop model of a discrete Voltage Controlled Oscillator.
The regular output voltage can be described with this continuous equation :

\begin{eqnarray} 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] \end{eqnarray}


The noise added in the the tunning voltage is a White Gaussian Noise.
The time domain integration of the input voltage is realized with the "EULERINTEGRAL" block that uses a discrete backward-Euler rule and the "VCOEVT" block produces events corresponding to zero crossings of the output waveform with a discrete method of detection.

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

\begin{figure}\begin{center} \epsfig{file=discr_vco_scope_1.eps,width=330.00pt} \end{center}\end{figure}
Figure : Input and output voltage of VCO

\begin{figure}\begin{center} \epsfig{file=discr_vco_scope_2.eps,width=330.00pt} \end{center}\end{figure}
Figure : Events generated by the VCOEVT block

\begin{figure}\begin{center} \epsfig{file=discr_vco_scope_3.eps,width=330.00pt} \end{center}\end{figure}
Figure : Events generated by the frequency divider block

Used blocks

See Also

Authors

A. Layec