EWOC Flashcards
What components are required for Electronic Attack?
Transmitter
Modulator
Power Amp
Antenna
Power Supply
Control System
What is Spoofing?
Sending false info to get an enemy to respond
What is passive jamming?
Using a passive method to prevent signal flow such as chaff
What is active jamming?
Putting energy on a target
What factors influence EA?
Power
Frequency
Modulation
Target Characterization
What are the types of jamming?
Active
Passive
Spoofing
What are destructive waves?
2 waves 180 degrees out of phase that cancel each other out
What are constructive waves?
2 in phase waves that add together to increase amplitude
Pros and Cons of Hybrid
Pro: more simple than mesh, more robust than star
Con: single points of weakness and more complicated than star
Pros and Cons of Mesh
Pro: more robust
Con: complicated
Pros and Cons of Star (Hub and Spoke)
Pro: Simple and cost effective
Con: Single point of weakness
What are the 3 topologies for VSAT?
Star (Hub and Spoke)
Mesh
Hybrid
What are the VSAT segments?
Ground Station
RF Link
Satellites
User
What is CJSR
Critical Jammer to Noise Ratio
Minimum dB required to jam a signal when you can match modulation - typically much less than 3dB power change
What is JSR
Jammer to Signal Ration
The ratio of jammer noise to the target signal
3dB is typically overkill
What does adaptive code modulation do?
Changes modulation and FEC automatically
What is automated uplink power control?
Automatically adjusts the power of an uplink to maintain Eb/no at a remote modem
What is Phase Shift Error (PSE)?
Percent deviation of a received symbol from desired phase
What is Error Vector Magnitude?
Percent of received symbol verse reference point
What is Eb/no?
Energy bits to noise ration
More energy bits=better signal
The more bits per symbol (bps) the higher the signal to noise ratio (SNR) is needed for the same __________?
Bit Error Rate (BER)
What is unique about regenerative satellites?
They demod, and remod signals to clean up the signal
What does a channelizer do?
It routes signals in 2 ways:
Fan-out: spread signal out over several beams
Fan-in: Takes signals from several beams into 1 beam
Digital Bent Pipe Satellites have_____?
Variable Transponder Translation Factor (Frequency) (TTF)
Spatial Frequency Reuse - reuses a frequency when transmitters are separated geographically
What does automatic gain control (AGC) do?
Prevents a satellite from receiving too much power
Pro and Con of Code Division Multiple Access (CDMA)
Pro - Jam resistant
Con - Expensive
Pro and Con of Time Division Multiple Access (TDMA)
Pro - Efficient use of bandwidth
Con - Need to consider transmission time delay–very precise time constraints and limited time slots
Pro and Con of Frequency Division Multiple Access (FDMA)
Pro - Simple and reliable
Con - Bandwidth inflexible
What is Multiple Access?
Happens after transmission, multiple signals being received by a receiver simultaneously
What is multiplexing?
Multiplexing is the process of putting multiple signals onto a carrier signal
What are the 3 types of Transmit and Receive properties, or multiplexing communication types?
Simplex - receive only (FM radio)
Half Duplex - send or receive one at a time (Walkie Talkie)
Full Duplex - Send and receive simultaneously (cell phone)
What is symbol rate?
Rate at which symbols are transmitted - or same as effective bandwidth
What is total bit rate?
Data rate plus Forward Error Correction (FEC)
What is data rate?
Speed of raw data
Define effective bandwidth
Effective bandwidth is your 3dB down bandwidth
Define occupied bandwitdh
Occupied bandwidth is the total bandwidth, noise floor to noise floor
What is the most common digital modulation?
Shift Key, which is turning a 1 into a 0 or vice versa
What are the types of digital modulation?
ASK - amplitude shift key
PSK - phase shift key
FSK - frequency shift key
IQ
What are the types of analog modulation?
AM
PM
FM
PWM
What does a modulator do?
Puts info on a carrier signal to send data
Why choose digital over analog?
More resistant to noise
Analog must be reproduced accurately
Digital only discrete needs reproduces
Digital has longer more robust comm path
Pros and Cons of analog signals
Pro - Easy to propagate
Infinite Data
Already in language
Con - Can be difficult to understand
Can’t be compressed
Pro and Con of Digital Signals
Pro - Easy to interpret
Compressible
Can add error correction
Con - Needs pre determined code
Needs a carrier wave
Slower data rates
Pro and Con of Phased Array
Pro - Can change beam
Resistant to jamming
Can follow forces
Serves multiple users
Con - More complex & expensive
Low frequency agility
Pro and Con of Steerable Spot
Pro - Narrow foot print
can follow forces
Con - Fewer users
Pro and Con of fixed spot
Pro - narrow footprint
Jam resistant
Con - small number of users
Can’t follow forces
Pro and Con of Earth Coverage
Pro - each satellite covers 1/3 of the earth
Con - does not cover poles
Easy to jam
Pro and Con of Multi-Beam
Pro - narrower foot print
More power density
Resistant to jamming
Con - smaller number of users
What are the different types of beams?
Multi-beam
Earth Coverage
Fixed Spot
Steerable Spot
Phased Array
What is an Orthomode Transducer?
An orthomode transduce is a component that allows an antenna to receive and see both polarities at once. It separates or combines signals with different polarities.
What are waveguides, and what do they do?
Waveguides are objects that guide your signal to ensure that you are transmitting in the proper band. They are different sized based on the band you are transmitting in.
What are the types of Antennas?
Isotropic - Theoretically perfect omnidirectional
Monopole - Length of antenna correlates to wavelength
Dipole - (Yagi Uda) directional
Aperture - (Parabolic) directional
Array
What is half power beam width?
It is a measurement in degrees from your antenna boresight to the 3dB down mark on the main lobe
What are the different types of gain?
Active - Power
Passive - Shape of antenna
Computational - added by the modem
What is gain?
Directivity + efficiency
What is Effective Isotropic Radiative Power (EIRP) and what does it represent?
EIRP is the total gain and power of a transmission compared to an isotropic antenna
What is antenna efficiency?
How well an antenna converts input power into RF waves
What is antenna directivity?
How well an antenna focuses energy
What is Transponder Translation Factor (Frequency)
TTF is an on satellite ratio of downlink to uplink frequency
What is the greatest factor in the success rate of a transmission?
The antenna
Describe Signal Flow
You start with a baseband that goes through the multiplexer into a modulator, from there you upconvert the signal and it passes through a high power amplifier to be transmitted to a satellite. On it hits the satellite the frequency is changed and it gets retransmitted to a ground station. At the ground station the signal goes through a low noise amplifier then to a downconverter. These two components are sometimes combines into an LNB (Low noise block), after these components the signal is demodulated, and then demultiplexed back into a baseband.
Define Faraday Rotation
Polarization twist due to a magnetic field
Define Scintillation
Rapid changes in waveform due to the magnetic field in the ionosphere
What are the advantages and disadvantages of circular polarization
Advantage - you don’t need precise orientation, you can receive linear with -3dB loss
Disadvantage - Right Hand Circular Polarization (RHCP) does not receive Left Hand Circular Polarization (LHCP) and you can’t reuse frequencies
What are the advantages and disadvantages of linear polarization?
Advantage - ability to reuse some bandwidth
Disadvantage - You need precise orientation of a polarizer to receive full signal
What is polarization?
Polarization is the orientation of your Electric Field, either in linear or circular
What is Free Space Loss?
Free Space Loss is the power lost between a transmitter and receiver due to the spreading of energy.
Every time you double the distance you quarter the power
What part of an Electromagnetic Wave can we manipulate?
The electrical field
What are the parts of an Electromagnetic Wave?
Electrical and Magnetic, and the two are perpendicular to each other
Define Scattering
Scattering is what occurs when a signal meets many small objects that reflect a signal, resulting in the signal being scattered. This is what chaff does.
Define Defraction
Defraction is the process in which a signal bends around an object such as a mountain peak.
Define Reflection
A signal bouncing off an object such as a skyscraper
Define Propagation
Propagation is how an Electromagnetic (EM) wave travels through a medium such as the vacuum of space
Define Amplitude
Amplitude is the height and depth of a sine wave representing power shown as dB
Define Phase
Phase is the angular measurement represented in degrees on a sine wave
Define Wavelength
Wavelength is the distance of a sine wave from one point to another completing 360 degrees
Define Frequency
Frequency is the number of cycles in one second represented in Hz
Define Period
Period is the time it takes to complete one cycle
Define Cycle
A Cycle is one complete vibration representing 360 degrees
What are the characteristics of a Sine wave?
Cycle
Period
Frequency
Wavelength
Phase
Amplitude
What is needed to declare Combat ID?
You need to have: (4+1)
Satellite
Transponder
Center Frequency (CF)
Frequency range and band
and
Signal type, or modulation, or Tactical function or IC Assessment
What is weight of effort?
A determination if an operation is worth the effort being put into it
What is timing and tempo?
A determination of the minimum effect required for a given operation
Define 1st, 2nd, and 3rd order effects
1st: effects on the target
2nd: effect on the structure/function of a network
3rd: effects on the operational environment
What are the 2 Electronic Attack authorities?
EMS coordinating authority (EMSCA)
EA Control Authority (EACA)
Define Electromagnetic Spectrum Operations (EMSO)
Maneuvering space to conduct effects and protect against EW fires
Which component command is responsible for jamming?
Joint Forces Air Component Command (JFACC)
What are the 2 types of combatant commands and their area of responsibility?
Geographic:
Northcom
Southcom
Centcom
Africom
Eucom
Indopacom
Spacecom
Functional:
USCYBERCOM
USSTRATCOM
USTRANSCOM
USSOCOM
What are the 2 functions of the DoD and what do they do?
Warfighting - Conduct war
Service - Organize, Train, and Equip (OT+E)
What are the 6 phases of conflict?
P0 - Shaping the battlefield
P1 - Deter
P2 - Seize initiative
P3 - Dominate
P4 - Stabilize
P5 - Enable Civil Authority
What is targeting?
Targeting is the process of selecting and prioritizing targets and matching the appropriate response to them
What bands do we use and what are their frequency ranges?
UFH - 300MHz - 3GHz
L 1-2GHz
S 2-4GHz
C 4-8GHz
X 8-12 GHZ
Ku 12-18 GHz
K 18-27 GHz
Ka 27-40 GHz
What is an ATO and what is it the same as?
An ATO is an Air Tasking order.
An ATO tasks execution and special instructions (SPINS) to provide amplifying guidance. It is the same as a CSTO or Combined Space Tasking Order
What is Eb/no?
Eb/no is energy bits to noise ration, or the quality of the signal over noise.
What is Bit Error Rate (BER)?
BER is the number of bit errors over the total transferred bits
What is the difference between Effective Radiated Power (ERP) and Effective Isotropic Radiated Power (EIRP)?
EPR is the power at the antenna with passive gain
EIRP is the total power at any point of the transmitted wave
Why is a parabolic antenna best for our career field?
It provides higher gain and directivity
What are the Electromagnetic Support mission areas?
1 Monitor
2 Characterize
3 Geolocate
What part of the Joint Tasking Cycle process does Del 3 do on a day to day basis?
Execution Planning and Force Execution
What is Time Difference of Arrival (TDOA)?
TDOA is the difference of arrival time of a signal from 2 or more satellites and it measures the time to determine the location of a target
What is Frequency Difference of Arriva (FDOA)?
FDOA uses doppler shift to locate a target
What antenna has a primary use of UHF?
Yagi Uda
Which has a higher probability of attribution: CW spike or Matched Wave Form? and why?
Matched Wave Form, because of the level of spectral awareness that goes into creating it.
What are 2 requirements for 2 Sat GEO?
- 2 satellites that are transmitting
- Your antennas must be in the downlink
- Orbital separation of the satellites
- Signal polarizations and Frequency must be similar
- 2 Adjacent satellites
- Reference emitter
- Ephemeres info must be up to date
- 2 Satellites must have same polarity
Limitations of 2 Sat GEO
- Geolocations are not guaranteed
- Bad time of day
- Inaccuracy in GPS timing could affect results
- No suitable secondary satellite
- Precise timing is required
- Not static
3 Types of control?
ADCON - Death, Discipline, and Decorations
OPCON - Organizing/reorganizing forces
TACON - Local control to where you are
What are the 7 Joint Warfighting Fundamentals?
1 - Command and Control
2 - Fires and Maneuvers
3 - Communications
4 - Intel
5 - Sustainment and Logistics
6 - Movement
7 - Security
What can Combatant Commanders delegate and to whom?
Warfighting - to the Joint Forces Combatant Commander
Describe Supporting vs. Supported
This is determined by who is the most important command, other components will support that command.
What are the J-Staff codes in order?
1 - Personnel
2 - Intel
3 - Operations
4 - Logistics
5 - Plans
6 - Communications
7 - Exercise and Training
8 - Contracting/Requirements
9 - Info Ops/STO/Space/EW
What are the J-Staff letter codes?
C - combined
J - Joint
G - General
S - Army/USMC/USSF
A - USAF
N - USN
What are the 6 stages of joint tasking and which does Del 3 participate in?
1) Objectives/Effects/Guidance
2) Target Development
3) Weaponeering
4) ATO Production and Dissemination
*5) Execution Planning and Force Execution
*6) Assessment
What is a periodic wave?
A periodic wave is a wave that repeats itself identically continually.
What is a non-periodic wave?
A non-periodic wave is one that does not repeat itself, and it unpredictable, such as a human voice.
What is heterodyning?
Heterodyning is the process of combining 2 signals
Who sends out the STO?
The AOC
Who receives the STO?
The STO is received by the Squadron Commander, DO, or Crew Commander depending on where you are located
What are the 2 types of Electromagnetic Interference (EMI)?
Active
Passive
What are the 2 main purposes for a Spectrum Analyzer?
Monitor
Characterization
What is total bit rate?
Data + Parity Bits
What are the 3 levels of Warfare?
Strategic
Operational
Tactical
What are the 3 tiers of effectiveness?
Tier 1) Effects on a Target
Tier 2) Effects on a Network
Tier 3) Effects on the Operational Environment
What does altering the Resolution Bandwidth on a Spectrum Analyzer do?
It adjusts the sampling of frequencies in a span
What does altering the Video Bandwidth on a Spectrum Analyzer do?
It applies a smoothing filter to decrease random noise fluctuations, and adjusts amplitude sampling
What is the process of going from a digital wave to an analog wave or an analog wave to a digital wave called?
Sampling
What is a Carrier Wave?
A carrier wave is an unmodulated wave with no data on it
What are the 3 different types of multipath fading?
Reflection
Defraction
Scattering
