Unit 1a Flashcards
INTRODUCTION
- Operations involve a joint task force made up of elements from different services.
- Requires a great deal of teamwork between the services as well as an understanding of the operating methods and interfacing capabilities of each service involved
- Tactical data links (TDL) are standardized communications links for use in transmitting digital information
- There are varied types of TDLs over varying frequency ranges and data formats. Additionally, the military employs various waveforms and systems, such as the Situation Awareness Data Link (SADL) and Enhanced Position Location Reporting System (EPLRS) to help interface joint service operations.
Spread Spectrum
- Refers to a system originally developed for military applications, to provide secure communications by spreading the signal over a large frequency band.
- a technique used in radio transmission based on the concept that the narrowband signal is manipulated (scrambled) prior to transmission in such a way that the signal occupies a much larger part of the RF spectrum then strictly needed.
- This makes the signal more robust against interference and jamming.
Pseudo Random Noise Code
- in the original concept, was only known to the parties at each end of the radio connection.
- Spread spectrum technology was invented in the 1940s, and has been used extensively since then for military and other applications that require robustness and resistance to jamming or eavesdropping.
There are two predominant techniques to spread the spectrum:
Direct Sequence Spread Spectrum (DSSS) - which introduces rapid phase transition to the data to make it larger in bandwidth.
Frequency hopping (FHSS) –
Direct Sequence Spread Spectrum (DSSS)
- Multiplication of the original data signal with a much faster pseudo random noise code, which is also called the spreading code.
This results in a scrambled signal with a much wider spectrum. - significantly improves protection against interfering signals, especially narrowband interference.
- multiple access capability when several different spreading codes are being used simultaneously. The use of DSSS for multiple access is called Code Division Multiple Access (CDMA), and is used e.g. in the 3rd generation mobile communications.
Frequency Hopping Spread Spectrum
- makes the narrow band signal jump in random narrow bands within a larger bandwidth.
- the RF frequency of the narrowband transmission is quickly changed within a certain range, according to a pseudo random noise code.
a hopping pattern can be observed in the spectrum. - avoidance technique, in other words if the hop coincides with someone else’s transmission on the same channel, the collision will take only the duration of the hop, which is typically in the order of milliseconds or even less.
- also provides a multiple access capability by using orthogonal hopping codes for different (logical) communication channels.
Joint Tactical Information Distribution System (JTIDS)/Multifunctional Information Distribution System (MIDS)
- is a high-capacity, digital information distribution system providing integrated communications, navigation, and identification capabilities.
- It provides secure, flexible, and jam-resistant information transfer in real time among the dispersed and mobile units, characteristic of modern armed forces.
-combines characteristics designed to overcome many of the limitations common to existing systems by providing for increased system capacity
and coverage, improved connectivity, survivability, jamming resistance, and reduced danger of data loss and data obsolescence.
(P.2) Joint Tactical Information Distribution System (JTIDS)/Multifunctional Information Distribution System (MIDS)
- terminals operate on the principal of Time Division Multiple Access (TDMA), wherein, time slots are allocated among all network participants to transmit and receive data.
- The TDMA architecture’s basic element is a single communication circuit or net that is shared by many users.
- The net is subdivided into time slots that can be assigned to individual JTIDS/MIDS participants (called JTIDS/MIDS Units (JUs)) for transmitting messages.
- The JTIDS/MIDS system operates in the 960 - 1215 MHz frequency band. JTIDS/MIDS uses both frequency hopping and direct sequence spread spectrum to be robust against intentional and unintentional interference.
Situational Awareness Data Link (SADL)/ Enhanced Positioning Location Reporting System (EPLRS)
- EPLRS is a joint service secure, jam-resistance data link that is primarily used by ground forces (US Army) for blue-force tracking (friendly troop position information) and digital data dissemination.
- EPLRS is a wireless, networked, digital data system specifically designed to provide/receive data to/from ground forces on the move.
It also aids in fratricide prevention because it allows weapons platforms to see where other EPLRS are located, even in a congested battled environment. - The airborne equivalent to EPLRS is the SADL used by the Air Force.
- SADL integrates modified USAF close-air support aircraft with the digitized battlefield information via EPLRS on their heads-up display showing where Army/Marine/ground radios are located.
(P.2) Situational Awareness Data Link (SADL)/ Enhanced Positioning Location Reporting System (EPLRS)
- SADL provides fighter-to-fighter, air-to-ground, and ground-to-air data communications that are robust, secure, jam-resistant, and contention-free.
- Contention-free means that multiple messages are not collided when attempting to access the communication channel at the same time. Also, SADL provides air-to-ground combat identification.
-Between EPLRS and SADL, there are more than 17,000 terminals operating in all four services. Like all UHF transmissions systems, EPLRS/SADL is limited to line-of-sight (LOS) operations. - Typical soldier range (e.g., vehicle-to-vehicle) is 5-8 miles. Ground-to-air range is dependent on the altitude of the airborne platform but can easily exceed 100 miles.
- EPLRS is designed to relay traffic from radio to radio so that beyond line-of-sight (BLOS) operation becomes routine. EPLRS has evolved from its early inception (circa late 1970s, with fielding in 1980) as a position location system only to a full-blown digital data link system. It now supports a subset of the J & K series messages.
FBCB2/BFT1
- is a United States military term for a GPS-enabled capability that provides military commanders and forces with location information about friendly (and despite its name, also hostile) military forces
-In NATO military symbology, blue typically denotes friendly forces. When all capitalized, the term refers to a specific defense contractors’ system, but the capability is found in many military and civilian mobile apps. - Blue Force Tracker (BFT) systems consist of a computer, used to display location information, a satellite terminal and satellite antenna, used to transmit location and other military data, a Global Positioning System receiver (to determine its own position), command-and-control software (to send and receive orders, and many other battlefield support functions), and mapping software, usually in the form of a geographic information system (GIS), that plots the BFT device on a map.
- The system displays the location of the host vehicle on the computer’s terrain-map display, along with the locations of other platforms (friendly in blue, and enemy in red) in their respective locations. BFT can also be used to send and receive text and imagery messages and has a mechanism for reporting the locations of enemy forces and other battlefield conditions (for example, the location of minefields, battlefield obstacles, bridges that are damaged, etc.).
FBCB2 JCR/BFT2
- is a technology upgrade from FBCB2/BFT to provide improved capability and ensure interoperability between Army and Marine Corps forces.
- The improvements include updated computer hardware and software, improved satellite connectivity.
-This version did not last long and was designed to be the bridge to JBC-P (Figure 1-3). The BFT2 applies to equipment updates which was just the fact that were more satellites launched and the change over from civilian to military satellite system.
The Joint Battle Command - Platform (JBC-P)
- is a networked mission command information system that enables Army and Marine Corps’ units to share near real-time friendly, enemy, and battlefield situational awareness, operational maps and graphics, and command and control (C2) messages.
- The Army and Marine Corps intend JBC-P to provide joint, platform level interoperability for operations centers, ground vehicles, aviation assets, and dismounted Soldier/Marine platforms operating in land/littoral-dominated joint battle space.
- JBC-P expands upon the previously released Force XXI Battle Command Brigade and Below (FBCB2) and FBCB2-Joint Capability Release (FBCB2-JCR) systems.
- This is the current version being used by the forces. The biggest change was the graphics and user operability are far superior to the earlier version JCR/BFT2.
- Also, the addition of communications security (COMSEC) devices. The COMSEC is loaded and contained via the KGV-72 device (Figure 1-4) designed and built by Harris Corporation. It is also used by all services. There were other software changes as update times on movement refresh rates are faster.
(P.2) The Joint Battle Command - Platform (JBC-P)
- Users of BFT systems include the United States Army, the United States Marine Corps, the United States Air Force, the United States Navy ground-based expeditionary forces (e.g., United States Naval Special Warfare Command (NSWC) and Navy Expeditionary Combat Command (NECC) units), the United Kingdom, and German Soldier System IdZ-ES+.
- The equipment used for the EPLRS systems was the computer using the VHF LOS Radio systems for data transmission. Then when the military switched to the BFT1 the system consisted of a computer JV5 (Figure 1-5) or portable version Toughbook with docking station, PLGR GPS Receiver (Figure 1-7), MT-2011 Satellite Transceiver (Figure 1-6), and a GPS External Antenna (hockey puck).
FBCB2 JCR/BFT2 brought along just upgrades to the equipment such as the DAGR GPS Receiver (Figure 1-7) and the upgraded MT-2025 Satellite Transceiver. With the JBC_P version coming online the hardware has all been upgraded to MFoCS systems that include dismountable Tablet PCs, Processor Units, keyboards, removable solid-state storage, Display Units, cabling, and installation kits designed for various platforms — all engineered rugged for continuous operation in a wide range of military and combat. This is basically the computing hardware for JBC-P providing it faster pc and lighter systems to include tablets. There are TOC(Tactical Operations Center) Kits (Figure 1-2, 1-8) for every version that have been used which is the systems located in commands Center of Command areas.
Tactical Data Links
- formerly known as tactical digital information links, involve transmissions of bit-oriented digital information.
- The TDL program applies to all bit-oriented message formats used in support of joint and combined operations for the Joint Interoperability of Tactical Command and Control Systems (JINTACCS).
-The TDL program facilitates information exchange between the US and Allied commands. - TDL is a Joint Chiefs of Staff (JCS)-approved standardized communication link suitable for transmitting machine-readable, digital information.
- There are many forms of data links used in the joint services, to include LINK 11, LINK 11B, LINK 16, EPLRS, and SADL.