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
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Communications I
RF radio frequency
How do these antennas work?
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Introduction to Space Systems and Spacecraft
Design University of Idaho
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Ground Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Spacecraft Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
W Power Density W/M2 S distance from
antenna to a point in space La atmospheric
loss EIRP effective isotropic radiated power
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna gain for a parabolic antenna
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
What is the affect on the gain of antennas with
frequency?
When perfect impedance match get 100 transfer
to antenna
Perfect impedance match get VSWR 1.0
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
What is the affect on the gain of antennas with
frequency?
What happens when VSWR gt 1.0?
Reflected wave
lt100 forward wave
Output power of antenna (gain) is less off
resonant frequency.
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
What is the affect on the gain of antennas with
frequency?
The gain on all antennas are frequency sensitive.
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna Polarization
Center fed ½ wavelength
¼ wavelength antenna above a ground plane
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna Polarization
Generated vertical electric field lines
Electric field lines from a ½ wave antenna
Vertically polarized antenna
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna Polarization
Horizontal electric field lines
Electric field lines from a ½ wave antenna
Horizontal polarized antenna
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna Polarization
Circular Polarization Helical Antenna
Spiraling electric field
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna Polarization
Rotating electric field
LHP left hand polarization
RHP left hand polarization
Circular Polarized Helical Antenna
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna Polarization
Polarized Antenna Coupling
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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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?
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Antenna Polarization
Didnt 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.
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Introduction to Space Systems and Spacecraft
Design Space Systems Design
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Communications - Antennas
Questions?
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Introduction to Space Systems and Spacecraft
Design Space Systems Design