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<CENTER><STRONG><FONT size=5>Frequency Shifter</FONT></STRONG></CENTER></H1>
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<P align=justify>General description</P></FONT></B>
<P align=justify>The Frequency shift shifts the original signal in the
frequency domain by the given amount of Herzes. With the frequency lock
switch, an automatic frequency scanning mode can be activated. In the
scanning, the user can give the target frequency and scanning area.
SkySweeper automatically tracks the most powerful frequency component in the
scanning area, and then calculates the necessary amount of the frequency
shift, so that the output signal frequency peak is in the given target
frequency. This is especially useful in tracking sinusoid signals.</P>
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<P>Configuration</P></FONT></B>
<P>Pressing the 'Config' button opens the following configuration
dialog.</P>
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<P align=justify><IMG height=318 src="Frequency Shifter.files/FreqShift.gif"
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<P>Parameters</P>
<P></FONT>Frequency tracking</P></B>
<P align=justify>This switch activates the frequency tracking function. In
the frequency-tracking mode the frequency shift value is automatically
calculated in real time.</P>
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<P align=justify>Target frequency</P></B>
<P align=justify>The Target frequency tells the frequency where the
frequency with most power in scanning area is shifted. This parameter is
active only in the frequency-tracking mode.</P><B>
<P align=justify>Scanning area</P></B>
<P align=justify>This is an area where the frequencies are scanned. The
frequency shift is automatically calculated so that the frequency with most
power will be in the target frequency in the block�s output. This parameter
is active only in the frequency-tracking mode.</P><B>
<P align=justify>Update interval</P></B>
<P align=justify>The Update interval is the interval between automatic
frequency shift estimations. This parameter is active only in the
frequency-tracking mode.</P>
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