High Frequency
what is the lowest frequency considered to be HF?
3 MHz
what is a signal transmitted from a satellite TO an earth terminal called?
Downlink
what is modulation?
Changing of from one state to another
"Mixing" signals to form a new output
converts an Intermediate Frequency up to a higher frequency
Block Up-converter
what height is a geosynchronous orbit about the equator?
23,000 miles
amount of resistance used by most radio systems
50 Ohms (rg-58)
how many GPS satellites are required for PRECISE timing.
4
an unmodulated signal carries
no information / it is only a crarrier wave
increases the power of a received signal
Low noise amplifier
What beam type is used to cover the largest geographical areas?
global Beam
what is the wavelength for 10 MHz
30 meters
MUOS and IW are examples of
tactical satellite communications
this type of modulation varies the amplitude of the RF
Amplitude Modulation (AM)
performs the modulation and demodulation of a given signal
Modem
what frequency range does X band operate in?
8-12 GHz
What does ALE do?
automatically selects the best predetermined frequency to use
What does the signal to noise ratio measure
the amount of desired signal compared to the background noise
a non-resonant antenna is used for what?
multiple frequencies
in the TX path this component increases the power to allow the signal to reach the satellite
High Powered Amplifier (HPA) we use SSPA's
geostationary orbits are measured by their position above which man made imaginary lines
longitude
polarization is
the orientation of the radiating elements (orientation of the antenna)
these are the TX bands currently used by JCSE
X and KU
What is the formula to find the wavelength of a given frequency?
wavelength = velocity / frequency
wavelength = speed of light (c or 300,000 Kms) / frequency
collects/reflects RF from a satellite to/from the feed horn
reflectors
which coverage type covers about 1/2 of the the global beam coverage
Hemispheric coverage