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56 Cards in this Set

  • Front
  • Back
Purpose of tactical communication:
to serve command
All communications systems must satisfy four basic requirements to be effective:
1. Reliability 2. Security 3. Speed 4. Flexibility
Communications Means (6):
1 Radio
2 Wire
3 Sound
4 Visual
5 Physical communications includes messenger (foot or motorized)
augmented by mail (guard mail or U.S. mail)
6 Data communications, which include all computer and data
transmission devices
Most secure communication mean:
Least secure communication mean:
Radio waves travel along
the surface of the earth (groundwaves) and up into the
atmosphere (skywaves).
Ground waves travel from the ___ ___ along the surface of
the earth
transmitting antenna
Several factors can affect the distance / range waves travel:
• Dense vegetation, mountainous terrain, or dry desert soil can have a negative effect on a ground wave.
• Manmade features, such as buildings, power lines or water towers, can reflect a radio wave into a new direction or absorb the signal.
• Severe weather, such as sandstorms, thunderstorms and blizzards, can affect your radio signal.
Planning Considerations 4:
1 Position your antenna on the military crest.
2 Position your antenna as far back as possible from obstacles in the direction you want to communicate.
3 Plan for and be prepared to use relay/retransmission stations.
4 Select a scheme of maneuver that allows you to avoid or exploit certain obstacles.
To reduce an enemies' ability to intercept your transmissions
position your antenna so a natural or manmade obstacle is between you and the enemy
Frequencies from approximately 2-12 MHz
Can use the property of
"bouncing" the radio signal off the ionosphere and the earth's surface
to increase the range of communications.
One problem with skywaves is they produce
"skip zones" (areas where
the signal does not return to earth) on the earth's surface.
Near Vertical Incident Skywave (NVIS) directs the radio wave at a
higher angle toward the sky, thus ensuring the reflected wave returns to earth closer to the transmitter and eliminating any skip zones.
NVIS communications can
communicate over high obstacles, such as mountains and travel up to 300 miles from the transmitting
High frequency
(HF) 2 to 29.999 MHz
Pros, Use, Equipment
Pros: Lower HF frequencies can
communicate over great distances
Used: when long haul communications are necessary
Equipment: AN/PRC-150/104, man portable radio
• AN/MRC-148/138, vehicle mounted radio
Very High Frequency (VHF)
30 to 87.975 MHz Pros/Cons
Very High
Frequency (VHF)
30 to 87.975 MHz
Extends slightly
beyond line of sight
(LOS) due to
diffraction or
bending of the
signal by the
• At frequencies in
the 30 MHz range,
acts like HF ground
• Range of reliable
generally no more
than 40 km and
often depends on
ο The power
output of the
ο Terrain
ο Atmospheric
Very High Frequency (VHF)
30 to 87.975 MHz Used
Most widely used in infantry
Very High Frequency (VHF)
30 to 87.975 MHz Equipment
• AN/PRC-119
• AN/VRC-88
• AN/VRC-89
• AN/VRC-90
• AN/VRC-91
• AN/VRC-92
• AN/VRC-145
Ultra High frequency (UHF)225 to 400 MHz Pros/Cons
• Strictly line of sight (LOS)
• Unable to bend around obstacles because UHF wavelengths are so small
• Range may extend for more than 500 km as long as aircraft is high enough to be within LOS
Ultra High frequency (UHF)225 to 400 MHz Used
• Ground-to-air communications
• Air-to-air communications
Ultra High frequency (UHF)225 to 400 MHz Equipment
• AN/PRC-117/113, man-portable
• AN/VRC-103/83, vehicular-mounted
Single Channel Ground Air Radio System: Primary MAGTF VHF radio
Frequency Hopping
A transmission technique that changes the frequency of a radio channel automatically at a pseudo-random rate common to both to the transmitter and receiver.
The number of frequencies SINCGARS will hop through will vary depending on the __.
SINCGARS will change
frequencies __ times hundred a __.
The more frequencies in the HOPSET,
the more resistant to
electronic warfare the network will be.
The five variables required to frequency hop are 5:
1. Hop Set 2. Transmission Security Key (TSK) 3. Transmission Encryption Key (TEK) 4. Time 5. Net Identifier (Net ID)
Hop Set:
The VHF frequencies that SINCGARS will hop through in
Frequency Hopping mode
Transmission Security Key (TSK):
The sequence in which the radio will hop within a HOPSET. It does not encrypt the signal or transmission
Transmission Encryption Key (TEK):
Encrypts and decrypts the
operator’s voice during the radio transmission.
Net Identifier (Net ID):
3-digit numeric code that determines where a specific frequency-hopping (FH) circuit begins frequency-hopping. This will be entered by the radio operator and it will correspond to a specific frequency within the hopset.
• 10-km range due to lack of power amplifier
• May be operated while
ο Mounted in a vehicle
Cο In a dismounted (man-pack) configuration
RT:1, RA:0
Man-packed SINCGARS
• 200m – 400m in lower power setting
• 400m – 5km in medium power
• 5km – 10km in high power
RT:1, RA:0
• Long-range, vehicle-mounted radio set with one power amplifier
• Used where the communication range must normally operate over long
distances (up to 40 km)
RT:2, RA:1
• A vehicle-mounted, dual configuration set of radios
• Consists of one
ο Short-range radio without a power amplifier
ο Long-range radio with a power amplifier
• Provides long-range (up to 40 km) and short-range (up to 10 km) operation in two nets, simultaneously
• Has an added power amplifier that provides one of the radio sets with a longrange communication
RT:1, RA:1
• Vehicle-mounted, dual configuration set
• Consists of one
ο Short-range radio, which can be man-packed configured
ο Long-range radio
• Provides long-range (up to 40 km); and short-range, (up to 10 km)
operations in two nets simultaneously
• Combines the features of a VRC-88 and VRC-90 into a single vehicle
RT:2, RA:1
• Vehicle-mounted, dual configuration set
• Consists of two long-range radios
• Used to meet dual, long-range (up to 40 km) communications requirements
• Is a VRC-89 with an additional power amplifier mount to provide
communications range up to 40 km to the second radio system
• This variation is common in highly mobile units like the artillery battalion, light
armored reconnaissance battalion, assault amphibian battalion, and in tank
RT:2, RA:2
• Vehicle with mounted, dual configuration set
• Consists of two long-range radios
• Used for VHF retransmission and command and control.
RT:2, RA:2
Communications Security (COMSEC) is the:
protection resulting from all measures designed to deny
unauthorized persons information of value that might be derived from the
possession and study of telecommunications or to mislead unauthorized persons in their interpretation of the results of such possession and study.
COMSEC is divided into four areas:
1. Cryptosecurity 2. Emission security 3. Physical 4. Transmissions security
Essential Elements of Friendly Information (EEFIs) are
specific items of
information that, if disclosed, could have a negative impact on friendly
operations. This is specifically enforced when transmitting over an
unencrypted or “open” net.
The EEFI list includes 7:
1 Position
2 Capabilities
3 Operations
4 Friendly Electronic Warfare
5 Personnel
7 Wrong circuit
is a procedural word that brings to the immediate attention of circuit operators the fact that an EEFI disclosure has occurred.
Electronic Warfare entails
the surveillance of the
electromagnetic spectrum for immediate threat recognition in support of electronic warfare operations and other tactical actions such as threat avoidance, targeting and homing.
MIJI Report
Meaconing, Intrusion, Jamming and Interference Report
Format for the MIJI Report: TUFT
• Time of interference
• Unit affected
• Frequency or frequencies affected
• Type of interference (jamming, imitative deception, etc.)
If the enemy is suspected of using imitative electromagnetic deception
Two manual telephones TA-1 and TA-312 with a range of:
TA-1: 4 miles
TA-312: 14 to 22 miles
• Planning Range: 20+ miles ground wave
• Frequency Range: (HF) 1.6000-59.9999
• Power Sources: BA-5590 (Lithium) 2 each, weight- 1.45 lbs.
• Power Output: 1, 5, 20 Watt (Mode Dependent)
• Weight: 9.9 lbs. without batteries, 11.35 lbs with batteries
• Crypto Unit: Internal COMSEC
AN/PRC-150 Radio Set
• Planning Range: 30+ miles ground wave (based on antenna employed)
• Frequency Range: (HF) 2 TO 29.9999 MHz
• Power Sources: BA-5590 (Lithium) 2 each, weight- 1.45 lbs.
• Power Output:
ο 20 Watts
ο 400 Watts (MRC-138 HMMWV)
• Weight: 12.8 lbs without batteries, 15.7 lbs. with batteries
• Crypto Unit: KY-99
AN/PRC-104 Radio Set
• Planning Range:
ο 200m–400m low power
ο 400m–5km medium power
ο 5km–10km high power
ο 10km–40km power amplifier
• Weight: 15.5 lbs without batteries, 16.95 lbs with batteries
• Crypto Unit: Internal COMSEC
• Frequency Range: (FM) 30-87.975 MHZ
• Present Channels: 6 automatic, 1 manual/1 cue for single channel
• Power Source: BA-5590 one each, weight 1.45 lbs.
• Power Output:
ο .5-Watts Low Power
ο 2-Watts Medium Power
ο 5-Watts High power
AN/PRC-119 Radio Set
• Transmission Range: UHF- LOS dependent, VHF- 5 to 10 miles, SATCOM- 300
miles (Network and channel access dependent)
• Frequency Range: 30.0000-512.0000
• Power Source: BA-5590 (LITHIUM) two each, weight- 1.45lbs
• Power Output: 10 Watts (VHF), 20 Watts UHF
• Weight: 13.8 lbs without batteries, 16.7 lbs. with batteries
• Crypto Unit: Internal COMSEC
AN/PRC-117 Radio Set
• Transmission Range: VHF- 0 to 5 miles, UHF- LOS dependent
• Frequency Range: 30.0000-512.0000
• Power Source: BA-5123 (3 VDC)
• Power Output: 5 Watts
• Weight: 2-4 lbs. (Battery type and accessory Dependent)
• Crypto Unit: Internal COMSEC
AN/PRC-148 Radio Set
• Transmission Range: Line of Sight (LOS)
• Frequency Range:
ο (VHF) 116 TO 149.975 MHz
ο (UHF) 225 TO 399.975 MHz
• Power Source: BA-5590 (LITHIUM) two each, weight- 1.45 lbs
• Power Output: 2-10 WATTS
• Weight: 13.8 lbs without batteries, 16.7 lbs with batteries
• Crypto Unit: KY-57
AN/PRC-113 Radio Set
• Range: 4 miles using WD-1 (slash wire)
• Power: Sound
• Signal: Visual and audible ringer
• Weight: 4 lbs
• Mode of Operation: The TA-1 will operate with other TA-1s, TA-312s and through
the SB-22 switch-board.
• Range: Maximum of 14 to 22 miles based on temperature and relative humidity
• Power: BA-3030s (D Cell batteries) two each
• Signal: Audible Ringer
• Weight: 10 lbs.
• Mode of Operation: The TA-312 will operate with other TA-312s, TA-1s and through
the SB-22 switch-board.
provide a 24-hour continuous worldwide, all-weather precise position and time
measurement. • Space segment (satellites)
• Control segment (monitor stations on Earth)
• User segment (GPS receivers)
Referred to as the PLGR or “plugger.”
AN/PSN-11 Precision Lightweight GPS Receiver (PLGR)