Block 8 Flashcards
All satellites consist of at least ____ subsystems PLUS the bus
Five
What are the five subsystems of a satallite?
- Power
- Propulsion
- Telemetry, tracking and control
- Beacon
- Communications
What are the characteristics of a satellite bus?
- It is the body of a satellite
- Interfaces with the launch vehicle
- Allows for flexibility and use in a variety of missions
Satellite subsystem ____ generates and regulates satellite power
Power subsystem
Satellite subsystem ____ makes minor orbital positional changes
Propulsion subsystem
Satellite subsystem ____ is the only method of monitoring and controlling all systems from the ground
Telemetry, tracking and control (TTC) subsystem
Satellite subsystem ____ is utilized for position determination
Beacon subsystem
Satellite subsystem ____ utilizes transponders to enable satellite traffic routing
Communications subsystem
The ____ is responsible for SATCOM operations
Control segment
What are the three divisions of a satellite control segment?
- Spacecraft control
- Payload control
- Network control
Control segment ____ is responsible for stabilization, maneuvering and repositioning of the entire spacecraft
Spacecraft control
Spacecraft control operators ensure correct spacecraft management using the ____
Telemetry, tracking and control and subsystem
Control segment ____ is responsible for operation and control of satellite internal systems that give the satellite purpose
Payload control
Control segment payload control ____ and ____ using the telemetry, tracking and control (TTC) subsystem
- Receives commands
- Sends performance data
Control segment ____ includes satellite control and earth monitoring stations on earth that maintain spacecraft orbit and longevity
Network control
The terminal segment of satellite operations consists of ____, ____ and ____ users
- Ground
- Airborne
- Naval
What are the four types of terminal segment equipment?
- Manpack
- Vehicle
- Naval
- Aerial
SATCOM provides ____ communications
Beyond LOS
A ____ is an object that maintains a circular or elliptical orbit
Satellite
What are the two types of satellites?
- Natural (celestial orbiting body)
- Artificial (man made object)
What are the two main types of artificial satellites?
- Weather
- Communications
What are examples of communications satellites?
- Broadcast
- Earth observation
- Military
- Navigational
- Scientific
- Search and rescue
LEO
Low earth orbit
MEO
Medium earth orbit
HEO
High earth orbit
GSO
Geosynchronous earth orbit
GEO
Geostationary earth orbit
LEO is ____ km to ____ km
160 km to 2000 km
MEO is ____ km to ____ km
2000 km to 35,786 km
HEO is ____ km
35,786+ km
Geosynchronous earth orbit (GSO) satellites are at a/an ____ angle and are positioned between the ____ and ____
- Inclined
- Equator
- North/south pole
Which satellite, due to its tilt and angle, will roam up and down in latitude?
Geosynchronous earth orbit (GSO)
Geostationary earth orbit (GEO) satellites are positioned over the ____ and maintain ____ above the earth
- Equator
- Same relative position
What do geosynchronous and geostationary satellites have in common?
- Both orbits are geocentric
- Both orbits are approximately 24 hours long
- Both orbits have large footprints
What are the three orbital patterns?
- Inclined
- Polar
- Equitorial
Which orbital pattern is between 0* and 90*?
Inclined
Which orbital pattern has nearly a 90* inclination angle?
Polar
Which orbital pattern has a 0* inclination angle?
Equatorial
SATCOM uses mandatory ____ and terminals can be ____ or ____
- Encryption
- Fixed
- Mobile
What are the limitations of SATCOM?
- One satellite can only cover 1/3 of the earth
- A network of satellites must be used for global coverage
- No continuous coverage at the poles
- Bandwidth is limited and expensive
SATCOM terminals can transmit and receive over ____, ____ and ____
- UHF
- SHF
- EHF
What are the characteristics of UHF satellite terminals?
- 300 MHz to 3 GHz
- SATCOM and LOS
- Can be obstructed by terrain and buildings
What are the characteristics of SHF satellite terminals?
- 3 GHz to 30 GHz
- High data rates, large bandwidth
- Can be directed in narrow beams
What are the characteristics of EHF satellite terminals?
- 30 GHz to 300 GHz
- Has high atmospheric attenuation
- High speed data links
- Support WLAN and broadband internet
____ is managed by MILSATCOM joint program office and provides secure voice and data communications support globally
Defense satellite communications system (DSCS)
Defense satellite communications system (DSCS) utilizes ____ frequencies and ____ orbiting satellites
- SHF
- Geosynchronous
Defense satellite communications system (DSCS) provides for which coverage patterns?
- Earth
- Area
- Spot beam
What are the limitations of the defense satellite communications system (DSCS)?
It has exceeded 10-year service life
____ is a constellation of geosynchronous satellites that provide tactical narrow band UHF SATCOM
Ultra high frequency follow-on (UFO)
____ includes EHF support for encrypted, jam-resistant survivable communication
Ultra high frequency follow-on (UFO)
Ultra high frequency follow-on (UFO) EHF package is capable of enhanced use with both ____ and steerable ____ antennas
- Earth coverage
- Spot beam
What are the limitations of the ultra high frequency follow-on (UFO)?
It has exceeded 14-year service life
____ records SATCOM use requirements and is the official DOD centralized database for current and future SATCOM requirements
Satellite database (SDB)
The satellite database (SDB) is maintained by the ____ and owned by ____
- Defense information systems agency (DISA)
- Joint staff
Defense information systems agency (DISA) processes requests and assigns users their ____
Satellite database (SDB) number
Satellites are shared resources and Satellite database (SDB) number allows for a unit to submit a ____
Satellite Access Request (SAR)
Why must satellite database (SDB) users submit mission specifics to central planning authority?
To justify & coordinate allocation of resources
An approved Satellite Access Request (SAR) results in a ____
Satellite Access Authorization (SAA)
What are the contents of a Satellite Access
Request (SAR)?
- Desired frequency band
- Aggregate data rates
- Deployment location
- Types of terminal(s) utilized
- Types of networks employed
- Access time
- POC
What is a spaced-based navigation system created and maintained by the US?
Global positioning system (GPS)
GPS satellites are in ____
Medium earth orbit (MEO)
How many satellites can be viewed from any point on earth?
7 to 9
What are the three GPS segments?
- Space segment
- Control segment
- User segment
Who develops, maintains, and operates space and control segments?
USAF
GPS space segment satellites has an orbital period of ____ and pass over the same location ____ a day
- Approximately 12 hours
- Twice a day
What is the GPS control segment ground stations responsible for?
- Tracking satellites
- Monitoring transmissions
- Performing analysis
- Sending executable commands
What are the three types of GPS control segment responsible facilities?
- Master control stations (MCS)
- Ground stations
- Monitor stations
What are the duties of GPS master control stations (MCS)?
- Ensure health and accuracy of satellite constellation
- Perform satellite maintenance, solver anomalies
- Reposition satellites when needed for optimal earth coverage
Schriever AFB, CO is the ____ and Vandenberg AFB, CA is the ____
- Primary GPS master control station (MCS)
- Secondary GPS master control station (MCS)
What are the characteristics of GPS ground antennas?
- Used to communicate with GPS satellites for command and control purposes
- Responsible for normal command transmissions
- Can be shared or dedicated to air force satellite control network (AFSCN)
- Provides increased flexibility, visibility and tracking
Kwajalein Atoll, Diego Garcia, Ascension Island and Cape Canaveral FL are ____
GPS ground antenna locations
What are the characteristics of GPS monitor stations?
- Track GPS satellites and send observations to the MCS
- Collect atmospheric data, range/carrier measurements and navigation signals
How many GPS global stations are there?
- 6 USAF
- 10 national geospatial intelligence agency
What consist of hundreds of thousands of US and allied military users, tens of millions of civil, commercial and scientific users?
GPS user segment
Any device that contains a GPS chip is part of the ____
GPS user segment
____ determines the receiver’s position on earth using timing signals from three satellites
Trilateration
One GPS satellite can only provide ____
Three GPS satellites can provide ____
A fourth GPS satellite can provide ____
- Time of day (TOD) based of the satellites atomic clock
- Accurate location
- Velocity details (speed, heading, altitude, etc)
GPS signals are broadcast on ____ and ____ bands
- L1
- L2
____ is a point ofr reference used in mapping and surveying
Map datum
Map datum is used to define the ____ and ____ of the earth
- Shape
- Size
What is the current global standard for map datum?
World geodetic system 1984 (WGS 84)
What are three examples of map coordinate systems?
- Latitude/longitude
- Universal transverse mercator (UTM)
- Military grid reference system (MGRS)
What uses the equator and prime meridian as reference points and is written as degrees, minutes, seconds OR in decimal format?
Latitude/longitude system
What was developed by the Army in 1947, assigns every location on earth a set of letters and numbers, and divides the earth in to 60 zones?
Universal transverse mercator (UTM)
What is derived from UTM but uses two letters to designate general areas, divides UTM into smaller zones is used by the military in locating positions on earth?
Military grid reference system (MGRS)
A Military grid reference system (MGRS) coordinate is a ____ meter grid square
100,000
What uses and easting and northing value to pinpoint and area?
Military grid reference system (MGRS)
Military grid reference system (MGRS) coordinates consist of what three parts?
- UTM grid zone designator
- 100,000 meter square identifier
- Numerical location (easting/northing number)
What are the characteristics of a grid zone deisgnator?
- Intersection of a UTM zone and a latitude band
- Result is UTM-standard 6x8 zone
- Identified by the zone number and latitude band letter
What are the characteristics of a 100,000 meter square identifier?
- Divides the UTM-standard zone into 100,000 meter squares-
- These new zones are measured using multiples of 100,000 meters
- Identified using a column letter and row letter
What are the characteristics of a numerical location?
- Location within 100,000 meter square
- Identified with up to 5 digits for easting and 5 digits for northing
Operators using incorrect datum risk calculating ____
Inaccurate coordinates
MGRS-Old is used for WGS 84 and other modern datums (T/F)
False (MGRS-New)
What are the characteristics of a defense advanced GPS receiver?
- Self-contained
- Hand-held
- 12-channel
- Dual frequency (L1 and L2)
- Includes selectve availability anti-spoof module
____ is when a malicious party impersonates trusted user to launch attacks, steal data or spread malware
Spoofing
What are the capabilities of a defense advanced GPS receiver?
- Installs and integrates with vehicles, joint host systems
- Provides accurate PVT
- Uses COMSEC for anti-spoof, anti-jam
- Stores 999 waypoints or 15 routes with 1,000 legs each
What are the limitations of a defense advanced GPS receiver?
- Required clear line of sight with satellites
- Position accuracy is reliant on the ability to acquire satellite signals
- Ideal use is an open area with no overhead obstruction
- Signals can still be jammed despite evolving anti-jam measures
Tactical Satellite Transceiver
(TACSAT) allows ____ to share ____
- Multiple user terminals
- A single channel
Tactical Satellite Transceiver
(TACSAT) utilizes which transmission methods?
- FDMA
- TDMA
- DAMA
- DASA
What are the characteristics of FDMA?
- Divides one channel into multiple frequency bands
- Each user transmits on their own frequency
What are the characteristics of TDMA?
- Divides one channel into multiple time slots
- Works well with voice signals, compressed video and high-speed data
- Each time slot transmits a digital piece of a signal in sequence with other sources
- Distant end receives the signal unbroken
What are the disadvantages of FDMA/TDMA?
- The frequency/time slot is permanently assigned
- If the slot is not used it can not be used by other stations
What are the characteristics of DAMA?
- Used to assign a channel to clients that don’t need it constantly
- Assigns voice/data channels based on user requests to primary channel controller (PCC)
- Enabled efficient and instantaneous assignment of channels on first come, first serve basis according to priority level
In DAMA who determines priority level?
Primary channel controller (PCC)
DAMA channels are typically on pair of frequencies, either ____ or ____
- Uplink
- Downlink
What are the characteristics of DASA?
- Dedicated DAMA link for users who require the highest bit rates, lowest delays and no chance for preemption
- Allows users exclusive use of 5 or 25 kHz channel bandwidth
- Users must request services through PCC
DAMA is available in ____ kHz and ____ kHz waveforms
- 5 kHz
- 25 kHz
DAMA waveforms consist of repeating frames, each frame is three segments, ____ and ____
- Two orderwire
- The voice/data transmitted
____ are circuits used for coordination, control and maintenance of the data link
Orderwires
What are the characteristics of 5 kHz DAMA?
- Primarily used for electronic messaging
- Frame length is 8.96 seconds
- PCC uses forward orderwires (FOW) and return orderwires to relay link information to and from the user
What are the characteristics of 25 kHz DAMA?
- Best utilized for voice traffic
- Frame length is 1.3866 seconds
- Uses channel control orderwires (CCOW) and return channel control orderwires (RCCOW)
What is used to synchrnoize a user terminal’s time with PCC and other networked DAMA users?
Network timing
What is the process by which a radio transmits a short RF burst to calculate propagation time to the satellite and is used to establish network timing?
Ranging
What must range before establishing communications with a satellite?
A terminal
Radio may use ____ or ____ ranging
- Active
- Passive
____ automatically sends uplink signals to the satellite to calculate propagation time from the radio
Active ranging
Active ranging is the default setting for ____
DAMA
What are the characteristics of passive ranging?
- Used in tactical situations where emissions security is critical
- Operator must input satellite location data (ephemeris) to calculate range to satellite
- Less accurate than active ranging
____ is the numerical representations of a radio in a DAMA network
Terminal base address
What are the characteristics of terminal base addresses?
- 00001 through 65535
- 00000 is reserved for PCC
- All DAMA users have a unique DAMA address for their terminal
Users must load radios with ____ to communicate over DAMA
Encryption keys
____ is an encryption method that encodes orderwire traffic between PCC and the user
Transmission security keys (TSK)
____ is an encryption method that encodes voice or data traffic
Traffic encryption keys (TEK)
Encryption codes are loaded with external COMSEC devices, such as?
- SKL
- CYZ-10
What are examples of internal crypoto modes for encryption?
- VINSON
- ANDVT
What are the four PCC sites that provide global access to DAMA?
- NCTAMS LANT
- NCTS Naples
- NCTAMS PAC
- NCTS Guam
NCTAMS LANT
Naval computer and telecommunicatinos area master station, Atlantic
What are the characteristics of NCTAMS LANT?
- Located in Virginia, USA
- Provides coverage to CONUS and the Atlantic ocean
NCTS
Naval computer and telecommunications station
What are the characteristics of NCTS Naples?
- Located in Naples, Italy
- Provides coverage to the Atlantic ocean, continental Europe, Africa and Indian ocean
What are the characteristics of NCTAMS PAC?
- Located in Hawaii, US
- Provides overlapping coverage to CONUS and Pacific ocean
What are the characteristics of NCTS Guam?
- Located in Guam
- Provides overlapping coverage for the Pacific ocean and Indian Ocean
What is the five step DAMA communications process?
- Access request
- Controller verification
- Resource assignment
- Communication
- Teardown
In DAMA step ____, the user send DAMA access request to PCC
Step 1 (access request)
In DAMA step ____, PCC receives request and verifies that the user is authorized using DAMA address
Step 2 (controller verification)
In DAMA step ____, PCC sends a FOW/CCOW to user authorizing login request
Step 3 (resource assignment)
In DAMA step ____, authorized users communicate using DAMA network
Step 4 (communication)
In DAMA step ____, users must send a circuit teardown prompt to PCC
Step 5 (teardown)
In DAMA step 5 (teardown) the user sends a ____ containing a logoff message to the PCC, then the PCC acknowledges and initiates disconnect with ensuing ____
- ROW/CCOW
- FOW/CCOW
What are the characteristics of an ad-hoc network?
- Nodes can be re-located or lost and still sustain a network
- Node links adjust automatically as devices relocate
- Auto adjusts as it routes traffic
____ is a wireless network of nodes
Ad-hoc network
What three things must an ad-hoc network factor in?
- Path loss/fading
- Power
- Topological changes
Ad-hoc networks maintain a low probability of ____ and ____
- Intercept
- Detection
In an ad-hoc network ____ and ____ limit detection
- Low transmit power
- Infrequent transmissions
An ad-hoc network is capable of ____, ____ and ____ data simultaneously
- Transmitting
- Receiving
- Routing
What are the characteristics of an ANW2 network?
- Accommodates 2 to 10 users
- Transmit voice and data simultaneously
- Manages multiple security classifications concurrently
ANW2 network has on-air speed rates of ____
5 Mbps
ANW2 utilizes what kind of encryption? (providing end-to-end encryption)
High assurance internet protocol encryption (HAIPE)
In an ANW2 network enabled radio, if the IP network fails what ensures communication?
Combat net radio (CNR)
Combat net radio (CNR) DOES NOT require HAIPE keys but DOES require ____, ____ and ____ to function
- Tx/Rx frequency
- TEK
- TRANSEC
ANW2 radios route traffic between devices automatically using ____
IPv4
ANW2 enabled devices are capable of transmitting and receiving data and voice for ____
10 devices
What are the five requirements for an ANW2 configuration to function with IPv4?
- Subnet mask
- Gateway address
- Client address
- Unicast address
- Multicast address