From d2f4d30ebcad7430e4f0495cae5c2b3a16be73ce Mon Sep 17 00:00:00 2001
From: rupak
Date: Tue, 21 Jan 2020 19:05:09 +0530
Subject: added help files

---
 help/en_US/ssbdemod.xml | 97 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 97 insertions(+)
 create mode 100644 help/en_US/ssbdemod.xml

(limited to 'help/en_US/ssbdemod.xml')

diff --git a/help/en_US/ssbdemod.xml b/help/en_US/ssbdemod.xml
new file mode 100644
index 0000000..1ce9be8
--- /dev/null
+++ b/help/en_US/ssbdemod.xml
@@ -0,0 +1,97 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!--
+ *
+ * This help file was generated from ssbdemod.sci using help_from_sci().
+ *
+ -->
+
+<refentry version="5.0-subset Scilab" xml:id="ssbdemod" xml:lang="en"
+          xmlns="http://docbook.org/ns/docbook"
+          xmlns:xlink="http://www.w3.org/1999/xlink"
+          xmlns:svg="http://www.w3.org/2000/svg"
+          xmlns:ns3="http://www.w3.org/1999/xhtml"
+          xmlns:mml="http://www.w3.org/1998/Math/MathML"
+          xmlns:scilab="http://www.scilab.org"
+          xmlns:db="http://docbook.org/ns/docbook">
+
+  <refnamediv>
+    <refname>ssbdemod</refname>
+    <refpurpose>This function performs Single Side Band Amplitude Demodulation</refpurpose>
+  </refnamediv>
+
+
+<refsection>
+   <title>Description</title>
+   <para>
+Z = SSBDEMOD(Y,Fc,Fs)
+demodulates the single sideband amplitude modulated signal Y
+with the carrier frequency Fc (Hz).
+Sample frequency Fs (Hz). zero initial phase (ini_phase).
+The modulated signal can be an upper or lower sideband signal.
+A lowpass butterworth filter is used in the demodulation.
+   </para>
+   <para>
+Z = SSBDEMOD(Y,Fc,Fs,INI_PHASE)
+adds an extra argument the initial phase (rad) of the modulated signal.
+   </para>
+   <para>
+Z = SSBDEMOD(Y,Fc,Fs,INI_PHASE,NUM,DEN)
+adds extra arguments about the filter specifications
+i.e., the numerator and denominator of the lowpass filter.
+   </para>
+   <para>
+Fs must satisfy Fs &gt;2*(Fc + BW), where BW is the bandwidth of the
+modulating signal.
+   </para>
+   <para>
+   </para>
+   <para>
+</para>
+</refsection>
+
+<refsection>
+   <title>Examples</title>
+   <programlisting role="example"><![CDATA[
+
+Fs =200;
+t = [0:2*Fs+1]'/Fs;
+ini_phase = 5;
+Fc = 20;
+fm1= 2;
+fm2= 3
+x =sin(2*fm1*%pi*t)+sin(2*fm2*%pi*t);
+y = ssbmod(x,Fc,Fs,ini_phase);
+o = ssbdemod(y,Fc,Fs,ini_phase);
+z = fft(y);
+zz =abs(z(1:length(z)/2+1 ));
+axis = (0:Fs/length(zz):Fs -(Fs/length(zz)))/2;
+
+figure
+subplot(3,1,1); plot(x);
+title(' Message signal');
+subplot(3,1,2); plot(y);
+title('Amplitude modulated signal');
+subplot(3,1,3); plot(axis,zz);
+title('Spectrum of amplitude modulated signal');
+z1 =fft(o);
+zz1 =abs(z1(1:length(z1)/2+1 ));
+axis = (0:Fs/length(zz1):Fs -(Fs/length(zz1)))/2;
+figure
+subplot(3,1,1); plot(y);
+title(' Modulated signal');
+subplot(3,1,2); plot(o);
+title('Demodulated signal');
+subplot(3,1,3); plot(axis,zz1);
+title('Spectrum of Demodulated signal');
+
+   ]]></programlisting>
+</refsection>
+
+<refsection>
+   <title>Authors</title>
+   <simplelist type="vert">
+   <member>Pola Lakshmi Priyanka, IIT Bombay</member>
+   </simplelist>
+</refsection>
+</refentry>
-- 
cgit