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Communications - Antennas Ref: SMAD Sections – 13 Communications Architecture. Introduction to Space Systems and Spacecraft Design Space Systems Design. Communications I. RF – radio frequency. How do these antennas work?. 2. Introduction to Space Systems and Spacecraft Design
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Communications - Antennas Ref: SMAD Sections – 13 Communications Architecture Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications I RF – radio frequency How do these antennas work? 2 Introduction to Space Systems and Spacecraft Design University of Idaho
Communications - Antennas Ground Antennas 3 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 4 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 5 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 6 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 7 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 8 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 9 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 10 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 11 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 12 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Ground Antennas 13 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 14 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 15 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 16 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 17 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 18 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 19 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 20 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 21 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 22 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 23 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Spacecraft Antennas 24 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas 25 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas W = Power Density – W/M2 S = distance from antenna to a point in space La = atmospheric loss EIRP = effective isotropic radiated power 26 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna gain for a parabolic antenna 27 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas 28 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas ( )2 29 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas 30 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas 31 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas 32 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas 33 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas 34 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas What is the affect on the gain of antennas with frequency? When perfect impedance match – get 100% transfer to antenna 100% Perfect impedance match – get VSWR = 1.0 35 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas What is the affect on the gain of antennas with frequency? What happens when VSWR > 1.0? Reflected wave <100% forward wave Output power of antenna (gain) is less off resonant frequency. 36 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas What is the affect on the gain of antennas with frequency? The gain on all antennas are frequency sensitive. 37 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization Center fed ½ wavelength ¼ wavelength antenna above a ground plane ~ ~ 38 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization Generated vertical electric field lines (B) (A) (C) Electric field lines from a ½ wave antenna Ground Vertically polarized antenna 39 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization Horizontal electric field lines (A) (B) (C) Electric field lines from a ½ wave antenna Ground Horizontal polarized antenna 40 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization Circular Polarization Helical Antenna Spiraling electric field 41 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization Rotating electric field Looking to forward end of antenna Counter clockwise rotating LHP – left hand polarization Looking to forward end of antenna Clockwise rotating RHP – left hand polarization Circular Polarized Helical Antenna 42 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization Polarized Antenna Coupling 43 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization V polarization? H polarization? LH circular? RH circular? What type of antenna polarization should be used on satellites and ground stations? What about when satellite is coming toward you? V polarization? H polarization? LH circular? RH circular? What about when satellite is going away from you? 44 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Antenna Polarization Didn’t answer the question of polarization on the ground and on the satellite??? Something tricky happens to the polarization as the RF passes through the atmosphere to and from the satellite. We will find out when we look further at the link equations. 45 Introduction to Space Systems and Spacecraft Design Space Systems Design
Communications - Antennas Questions? 46 Introduction to Space Systems and Spacecraft Design Space Systems Design
