<?xml version="1.0" encoding="UTF-8"?>
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<refentry xml:id="griffitc" xml:lang="en"
          xmlns="http://docbook.org/ns/docbook"
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          xmlns:svg="http://www.w3.org/2000/svg"
          xmlns:scilab="http://www.scilab.org"
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          xmlns:mml="http://www.w3.org/1998/Math/MathML"
          xmlns:db="http://docbook.org/ns/docbook">

  <refnamediv>
    <refname>griffitc</refname>
	<refpurpose>Test signal example C of Griffiths' paper</refpurpose>
  </refnamediv>

<refsynopsisdiv>
   <title>Calling Sequence</title>
   <synopsis>
   	[SIG,IFLAWS] = griffitc(N)
   	[SIG,IFLAWS] = griffitc(N, SNR)
   </synopsis>
</refsynopsisdiv>

<refsection>
   <title>Parameters</title>
   <variablelist>
<varlistentry>
        <term>N  :</term>
        <listitem>
          <para>a positive integer:  number of points in time of the signal (default: 200) </para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>SNR  :</term>
        <listitem>
          <para>a positive scalar: the signal to noise ratio (default: 25 dB).</para>
        </listitem>
      </varlistentry>
       <varlistentry>
        <term>SIG     :</term>
        <listitem>
          <para>a complex column vector of size N: the signal.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>IFLAWS :</term>
        <listitem>
          <para>a N by 3 real array : the instantaneous frequencies of the 3 components .</para>
        </listitem>
      </varlistentry>
   </variablelist>
</refsection>

<refsection>
   <title>Description</title>
   <para>
griffitc generates the test signal of  the example C of the paper of Griffiths.
</para>
</refsection>

<refsection>
   <title>Examples</title>
   <programlisting role="example"><![CDATA[
   [sig,iflaws] = griffitc(); 
   plot(iflaws); xgrid;
   xlabel(_("Time"));
   ylabel(_("Normalized frequency"))
   xtitle(_("Instantaneous frequency laws"))
   ]]></programlisting>
   <scilab:image><![CDATA[
   [sig,iflaws]=griffitc(); 
   plot(iflaws); xgrid;
   xlabel(_("Time"));ylabel(_("Normalized frequency"))
   xtitle(_("Instantaneous frequency laws"))
    ]]></scilab:image>
</refsection>
<refsection>
   <title>References</title>
<para>L.J. Griffiths, "Rapid measurement of digital instantaneous frequency", IEEE Trans on ASSP, Vol 23, No 2, pp 207-222, 1975.</para>
</refsection>
<refsection>
   <title>Authors</title>
   <simplelist type="vert">
   <member>H. Nahrstaedt - Aug 2010</member>
   <member>F. Auger, July 1995.</member>
   </simplelist>
</refsection>
</refentry>
