Teleteknikk Digital kommunikasjon Forelesning 9.02.2004

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Teleteknikk Digital kommunikasjon Forelesning
9.02.2004

• Dagens tema
• Digital modulasjon
• Schiller Mobile Communications
• Kapittel 2.6 og 2.7
• Telelab starter denne uke
• De fleste foiler er hentet fra Jochen Schillers
  hjemmeside

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Digital Modulation and demodulation
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Digital modulation
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Advanced Frequency Shift Keying
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Example of MSK
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Advanced Phase Shift Keying
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Quadrature Amplitude Modulation
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16 quadrature amplitude modulation
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Hierarchical Modulation
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Multi-carrier modulation (1)
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Multi-carrier modulation (2)
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Modulation applet

• http//williams.comp.ncat.edu/Networks/modulate.ht
  m

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Spread spectrum patented by Heddy Lamar and
George Antheil 1941
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Spread spectrum technology
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Effects of spreading and interference
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Spreading and frequency selective fading
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DSSS (Direct Sequence Spread Spectrum) I
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Pseudo Random Generator

• http//www.eas.asu.edu/7Eapapand/applet/TF_JAVA/a
  pplet.html

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DSSS (Direct Sequence Spread Spectrum) II
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FHSS (Frequency Hopping Spread Spectrum) I
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FHSS (Frequency Hopping Spread Spectrum) II
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FHSS (Frequency Hopping Spread Spectrum) III
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Undervisningsfri neste uke.Neste forelesning
23.2.2004