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Abhören Von Funksignalen Durch Extraterrestrische Lebensformen

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Abhören Von Funksignalen Durch Extraterrestrische Lebensformen Abhören von Funksignalen durch extraterrestrische Lebensformen Diplomarbeit zur Erlangung des akademischen Grades eines Magisters der Naturwissenschaften an der Karl-Franzens-Universität Graz vorgelegt von Andreas Franz KLAUSNER am Institut für Physik Begutachter: Univ.-Prof. Dr.phil Arnold Hanslmeier Graz, 2018 Eidesstattliche Erklärung Ich erkläre eidesstattlich, dass ich die vorliegende Arbeit selbstständig und ohne fremde Hilfe verfasst, andere als die angegebenen Quellen nicht benutzt und die den Quellen wörtlich oder inhaltlich entnommenen Stellen als solche kenntlich gemacht habe. Die Arbeit wurde bisher in gleicher oder ähnlicher Form keiner anderen inländischen oder ausländischen Prüfungsbehörde vorgelegt und auch noch nicht veröffentlicht. Die vorliegende Fassung entspricht der eingereichten elektronischen Version. Datum: _________________ Unterschrift: _________________________ Inhaltsverzeichnis Forschungsfragen .................................................................................................................................... V 1. Einleitung ......................................................................................................................................... 1 2. Ausbreitung elektromagnetischer Wellen ...................................................................................... 2 2.1 Geschwindigkeit von elektromagnetischen Wellen ............................................................ 4 2.2 Energietransport von elektromagnetischen Wellen ........................................................... 5 2.3 Zusammenhang zwischen Strahlungsintensität und Abstand von der Quelle .................... 6 2.4 Ausbreitung elektromagnetischer Strahlung in 50 Jahren .................................................. 7 2.5 Wien´sches Verschiebungsgesetz und Planck´sches Strahlungsgesetz ............................... 9 3. Leistung von terrestrischen Signalen: ........................................................................................... 12 3.1 Ultrakurzwellen: ................................................................................................................ 12 3.2 Leistung von Ultrakurzwellensendern: .............................................................................. 14 3.3 Leistungsabschätzung von elektromagnetischen Wellen ................................................. 15 3.4 Gerichtete Aussendung elektromagnetischer Wellen ...................................................... 16 3.5 Die Friis-Übertragungsgleichung ....................................................................................... 19 3.5.1 Einheiten ........................................................................................................................ 20 3.5.2 Freiraumdämpfung und Leistungsübertragungsbilanz ................................................. 22 3.5.3 Beispiele ........................................................................................................................ 25 4. Radioteleskope .............................................................................................................................. 31 4.1 Sensitivität von Radioteleskopen .......................................................................................... 32 4.1.1 Einflussfaktoren auf die Sensitivität: ..................................................................................... 34 4.1.2 Kosmisches Hintergrundrauschen ......................................................................................... 36 5. Abschätzung der terrestrischen Senderdichte .............................................................................. 37 5.1 Sender.................................................................................................................................... 38 5.2 Erhebung von Referenzdaten und Entwicklung von Funktionen .......................................... 39 5.2.1 Entwicklung der exponentiellen Funktion ............................................................................. 43 5.2.2 Entwicklung der linearen Funktion ........................................................................................ 48 5.3 Weitere Einflussfaktoren: ...................................................................................................... 51 5.4 Abschätzung der kumulativen regionalen Sendeleistung ..................................................... 55 6. Mögliche Detektion terrestrischer Signale .................................................................................... 58 6.1 Exoplaneten ........................................................................................................................... 58 6.2 Habitable Zonen .................................................................................................................... 61 6.3 Banden und Fenster der Atmosphäre ................................................................................... 64 6.4 Berechnung der größtmöglichen Distanz .............................................................................. 66 7. Resultate ........................................................................................................................................ 69 I 7.1 Diskussion der Resultate ....................................................................................................... 70 8. Zusammenfassung ......................................................................................................................... 73 Literaturverzeichnis ............................................................................................................................... 75 Onlinequellenverzeichnis ...................................................................................................................... 77 Anhang .................................................................................................................................................. 80 II Abbildungsverzeichnis Abbildung 1: Ausbreitung elektromagnetischer Wellen im Raum ........................................................ 2 Abbildung 2: Phasen des elektrischen und magnetischen Feldes .......................................................... 3 Abbildung 3: Ausbreitung einer elektromagnetischen Welle im Fernfeld............................................. 3 Abbildung 4: Exponentielle Intensitätsabnahme elektromagnetischer Strahlung (1-50 ly) ................... 8 Abbildung 5: Exponentielle Intensitätsabnahme elektromagnetischer Strahlung (20-50 ly) ................. 8 Abbildung 6: Wien´sches Verschiebungsgesetz .................................................................................. 10 Abbildung 7: Relation von Wellenlänge, Frequenz und Energie ......................................................... 14 Abbildung 8: Strahlungsintensität bei gerichteter Strahlung ............................................................... 18 Abbildung 9: Vergleich des exponentiellen und linearen Leistungsverlaufs ....................................... 22 Abbildung 10: Freiraumdämpfungsfaktor über Strecke für verschiedene Frequenzen ....................... 24 Abbildung 11: Vereinfachte Darstellung einer Kommunikationsübertragung .................................... 27 Abbildung 12: Leistungsabnahme der el. Strahlung für eine Strecke von 1 m bis 20 m ..................... 29 Abbildung 13: Radioteleskop Effelsberg ............................................................................................. 31 Abbildung 14: Beobachtung und Erwartungswert ............................................................................... 33 Abbildung 15: T-휆 - Zusammenhang der kosmischen Hintergrundstrahlung...................................... 36 Abbildung 16: Frequenz-Intensitäts-Diagramm kosmischen Hintergrundstrahlung ........................... 37 Abbildung 17: Sendeantennen (Graz 1, Rostock-Toitenwinkel, Berliner Fernsehturm) ..................... 39 Abbildung 18: Verzeichnis, welches für die Recherche benutzt wurde ............................................... 40 Abbildung 19: Datenauswertung für Österreich mit Excel (1) ............................................................ 40 Abbildung 20: Datenauswertung für Österreich mit Excel (2) ............................................................ 41 Abbildung 21: Graph der Exponentialfunktion .................................................................................... 46 Abbildung 22: Darstellung der linearen Funktionen im Intervall [0,10] (MATLAB) ......................... 49 Abbildung 23: Für die Untersuchung herangezogene Staaten ............................................................. 51 Abbildung 24: Vergleich der unkorrigierten mit den korrigierten Werten .......................................... 54 Abbildung 25: Strahlungsleistungen diverser Länder .......................................................................... 54 Abbildung 26: Temperatur in Abhängigkeit zum Abstand .................................................................. 62 Abbildung 27: Habitable Zonen für Hauptreihensterne ....................................................................... 62 Abbildung 28: Kontinuierliche habitable Zone .................................................................................... 63 Abbildung 29: Atmosphärische Fenster für elektromagnetische Strahlung ......................................... 65 Abbildung 30: Frequenzabhängige Distanz der berechneten elektromagnetischen Welle .................. 70 Abbildung
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