ANVENDELSE AV DET NÆRE VERDENSROM

Transkript

1 NORDIC TEACHER SPACE CAMP 2013 ANVENDELSE AV DET NÆRE VERDENSROM Prof. em. Gunnar Stette Slide 1

2 CV Gunnar Stette Siv.ing. NTH 1962, Dr. grad SHAPE Technical Centre, Haag, Nederland, satellittkommunikasjon, NATO III satellittsystem, Professor radiokommunikasjon, NTNU SpaceTech programme, part time, University of Delft, Deltaker satellittprosjekter, spesielt NORSAT, nasjonalt system nor norske oljefelter SUDOSAT, Sudan DOmestic SATellite System INMARSAT etablering, medlem teknisk komite NORDSAT og Tele-X prosjektet Organisasjoner ESA, the European Space Agency ETSI, the European Telecommunications Standards Institute DVB, Digital Video Broadcasting CEPT, Electronic Communications Committee (ECC) Slide 2

3 Månelanding 20. juli 1969 Slide 3

4 6. August 2012, landing på Mars Slide 4

5 Rosetta på vei til komet. På vei til kometen 67P/Churyumov-Gerasimenko Command 31 June placing ESA s Rosetta comet-chaser into deep-space hibernation for 31 months until waking up in 2014 for arrival at its comet destination. -Oppskyting 2 mars Levering lander nov Perihelionpassering x 2.1 x 2.0 meter kg - hvorav 1670 kg drivstoff -165 kg vitenskapelig instrumenter kg lander Slide 5

6 Astronomiske observasjoner A star is born Hubbleteleskopet Observasjon av rommet fra en plattform utenfor atmosfæren. Slide 6

7 Mikrogravitasjon Uten gravitasjon Slide 7

8 Hva kan vi gjøre i bane rundt jorda? Slide 8

9 Utnyttelse av rommet til telekom. Arthur C. Clarke 16 December March 2008 Slide 9

10 Coverage from GEO GEO = Geostationary Earth Orbit Slide 10

11 En ettertraktet naturressurs Slide 11

12 Værkart Slide 12

13 Jordobservasjon Opptak av Engeløya fra QuickBirdsatellitten 4. juni Slide 13

14 Måling av metan Slide 14

15 ENVISAT Characteristics Launch Date March 1, 2002 Launcher Ariane V Launch mass 8200 kg Payload mass 2050 kg Mission length 5 years Number of instruments 10 Orbit Sun synchronous Altitude 800 km Inclination 98 degrees Slide 15

16 Satellittnavigasjon Slide 16

17 GPS-mottaker Banehøyde: Banehastighet: km 3,9 km/s Nøyaktighet vanlig bruk: noen meter Spesielle anvendelser: Slide 17 Med radiobølger: < 1 cm 1 nanosekund tilsvarer 30 cm

18 Pløying og såing med GPS Slide 18

19 Banemekanikk T 2 3 a Slide 19

20 Løsning av baneligningen Newtons første lov F =m r Newtons andre lov (tyngdelov) F g r KMm r 3 Baneligningen r = - r 3 r r p 1 cos NAROM 2010 Slide 20

21 Kjeglesnitt (Conical Section) Slide 21

22 Himmelkula Nordlige himmelkule X Declination Ekvatorialplanet Y Rektasensjon satellitt Sørlige himmelkule Slide 22

23 Baneplanet Inklinasjon i Orientering Ω Baneparametre Ellipsen Størrelse: lang halvakse Form: eksentrisitet Orientering ω Posisjon i ellipsen ν(t) Slide 23

24 TYPES OF ORBITS Banene er karakterisert ved: Form Størrelse Helning Orientering Slide 24

25 The geostationary orbit (the Clarke-orbit) Radius km Altitude 100 km Altitude km Equator The geostationary orbit Slide 25

26 Coverage from GEO GEO = Geostationary Earth Orbit Slide 26

27 Anvendelse av Keplers 2. lov: Molniyabanen Inklinasjon 63.4 deg., av grunner vi skal se på senere. Slide 27

28 Banesporet for Molniyasatellittene Slide 28

29 HIGHLY INCLINED ORBITS Slide 29

30 SATELLITT I LAV POLBANE Typisk 14 omløp per døgn Jorda roterer men banen ligger fast i rommet. Slide 30

31 Svalsat Slide 31

32 Sun synchronous orbits (1) Slide 32

33 Sun synchronous orbits (2) Slide 33

34 THE CLASSICAL ORBITAL PARAMETERS i = the inclination = the right ascension of the ascending node a = the semi major axis e = the eccentricity = the length of perigee = the true anomaly (time varying) The equation of movement is then d e dt a ( 1 e ) ( cos ) Slide 34

35 TLE, Two Line Elements AAAAAAAAAAA 1 NNNNNU NNNNNAAA NNNNN.NNNNNNNN +.NNNNNNNN +NNNNN-N +NNNNN-N N NNNNN 2 NNNNN NNN.NNNN NNN.NNNN NNNNNNN NNN.NNNN NNN.NNNN NN.NNNNNNNNNNNNNN Line Number of Element Data Satellite Number International Designator (Last two digits of launch year) International Designator (Launch antall of the year) International Designator (Piece of launch) Epoch Year (Last two digits of year) Epoch (Julian Day and fractional portion of the day) First Time Derivative of the Mean Motion (rev/day^2)or Ballistic Coefficient (Depending of ephemeris type) Second Time Derivative of Mean Motion (Blank if N/A) BSTAR drag term if GP4 general perturbation theory was used.otherwise, radiation pressure coefficient Ephemeris type Element Check Sum (Modulo 10) Slide 35

36 TLE (cont d) AAAAAAAAAAA 1 NNNNNU NNNNNAAA NNNNN.NNNNNNNN +.NNNNNNNN +NNNNN-N +NNNNN-N N NNNNN 2 NNNNN NNN.NNNN NNN.NNNN NNNNNNN NNN.NNNN NNN.NNNN NN.NNNNNNNNNNNNNN Line 2 Column Description Line of Element Data Satellite Inclination [Degrees] Right Ascension of the Ascending Node [Degrees] Eccentricity (decimal point assumed) Argument of Perigee [Degrees] Mean Anomaly [Degrees]CELESTRAK Mean Motion [Revs per day] Revolution at epoch [Revs] Check Sum (Modulo 1 0) Celestrak WinTrak Pro 6.0.LNK Slide 36

37 JULIAN DATE Juliansk reference: 1200 (middag) 1 januar 4713 BC 31. desember = 0. januar Middag 1. januar er dag 1,5 Julian date Juliansk datum for 0915 o clock on 11 October 1997 Starting value The year October o clock 9/ min =15/(24x60) Total Slide 37

38 TLE - Data line 1 Slide 38

39 IRIDIUM Orbit planes: 6 Satellites per orbital planes: Altitude: 780 km Inclination: 86.4 degrees Period: 100 min Visible time each satellite: 11.1 min Transmission delay 2.6 ms min 8.2 ms max Coverage: global Slide 39

40 Oversikt Satellittbane Oppskyting Miljøet i rommet Posisjonering, mekanisk struktur strømforsyning, Satellitttemperaturkontroll plattform telemetri, fjernkontroll retningskontroll Slide 40

41 THE ARIANE FAMILY 47 m 58 m Solid or liquid strap-on boosters Solid strap-on boosters Slide 41 AR 1 AR 2 AR 3 AR 4 AR t 217 t 237 t 470 t 750 t

42 ARIANE 5 Description : Total height : from 45 to 55.9 meters Maximum diameter : 12.2 meters Thrust at lift off : kn Lift of mass : 710 to 718 tonnes Performance in GTO* : from 5.9 tonnes for a single satellite launch to 6.9 tonnes for a dual launch. EPC (EADS LAUNCH VEHICLES) Height : m Propellants : tonnes of LOX; 25,84 t. LH2 Structure : Aluminium AZ 2219 (Cryospace) Engine : Vulcain (SNECMA-SEP) Combustion duration : about 590 seconds Diameter : 3 m Dry mass : 40 tonnes each Propellants : 237 tonnes each of solid propellants Slide 42

43 Miljøfaktorer i rommet Slide 43

44 Magnetosfæren Slide 44

45 ORBITAL DEBRIS The US Air Force Space Command tracks more than 7000 objects >10 cm in LEO, spent rocket stages, fragments of rockets and satellites, etc Slide 45

46 Satellitter i rommet Fra 4. oktober 1957 til 1. januar oppskytinger 6000 satellitter 800 i drift Slide 46

47 Kollisjon i rommet, 10 februar 2009 Iridium 33 and Cosmos 2251 Iridium pieces of debris (16 pieces of which have already decayed from orbit) Cosmos pieces of debris (30 pieces of which have decayed) associated with Slide 47

48 Attitude control PLATFORM FUNCTIONS Spinning satellites Three-axis stabilization Attitude determination Propulsion for orbit and attitude control Power supply Solar cells Batteries Thermal control Passive thermal control Active thermal contro TT&C System Mechanical structure, reliability, etc. etc. Slide 48

49 Satellitt uten retningskontroll Slide 49

50 Utvikling av rotasjonsstabiliserte satellitter Slide 50

51 Referansesystem satellitt Slide 51

52 Potocnik 1929 STRØMFORSYNING Siden 1952: Solceller Slide 52

53 ECLIPSE FOR GEO SATELLITES A geostationary satellite passes through the shadow of the earth around spring and autumn equinox. The longest duration is 70 min, and the number of days is about 50 at each equinox. Slide 53

54 THERMAL PROPERTIES The important parameter is the ratio / White colour Black colour Gold Optical sun reflector Solar cells Slide 54 Homogeneous sphere: Altitude(km) Surr. temp. White(deg) Black(deg) Gold(deg) (1250)

55 MARISAT (spinner) Antenna assembly (despun) MARISAT (Comsat General) First maritime civilian satellite Solar panel Rotary joint Propellant for on orbit operations, attitude etc. Apogeum Motor Platform for payload electronics Slide 55

56 . Slide 56

57 Telecommunications Slide 57

58 ACTIVE SATELLITES AMPL. ACTIVE SATELLITE Slide 58

59 The earth seen from the GEO Slide 59

60 Why is satellite communications so demanding? Each data bit need an energy that is higher than the noise. The higher bitrate, the higher received power is required. Slide 60

61 Intercontinental communications Mottakerantenne i Pleumeur Bodot (vekt 340 tons høyde 60 meter) Telstar 10 July 1962 Slide 61

62 INTELSAT INTELSAT established i member countries operates 25 satellites 36 nationale systemes Global system in 1969 Slide 62

63 INTELSAT Standard A (Umm Haraz) Slide 63

64 INMARSAT INMARSAT established in 1981 Operates now 8 satellites Slide 64

65 INMARSAT USER TERMINALS INMARSAT A Maritime version G/T = -4 db/k Antenna diameter 1 meter Analog voice plus telex Land mobile version Slide 65

66 DIGITAL USER TERMINALS Inmarsat Bt(voice, data) Inmarsat M (voice,data) Inmarsat C (600 bit/s data) Hand held Slide 66

67 INMARSAT Mini M and M4 INMARSAT mini-m, portable, semi-fixed and maritime version, light, 2 kg, INMARSAT s most popular model, US$ 3000, $2.70 per minute INMARSAT M4, end 1999, GAN service, speech at 4,8 kbit/s, data up to 64 kbit/s, ISDN, PDS (Inmarsat Packed Data Service), Internet access, video conferencing etc. Slide 67

68 INMARSAT BGAN: Broadband Global Area Network Opp til 492 kbit/s Slide 68

69 SYSTEMER FOR LOMMETELEFONER The geostationary orbit is too far away Lower orbit require satellite configurations for cont. coverage Low orbits gives reduces transmit power but also an increased number of satelllites Slide 69

70 IRIDIUM Orbit planes: 6 Satellites per orbital planes: Altitude: 780 km Inclination: 86.4 degrees Period: 100 min Visible time each satellite: 11.1 min Transmission delay 2.6 ms min 8.2 ms max Coverage: global Slide 70

71 IRIDIUM Slide 71

72 IRIDIUM Slide 72

73 GMR Geo-Mobile Radio Main idea: Extension of the successful GSM system ACeS Thuraya Slide 73