Warfighter Information Network (WIN)
Master Plan (Version 3 - June 3, 1997)

Chapter 5

Satellite Transport Systems

5.1 Introduction.

a. The Warfighter has a continuing requirement for satellite communications (SATCOM) systems to satisfy growing information transfer needs. SATCOM is often the primary communications means available to support US military operations in a global threat environment of regional conflicts that are unpredictable in location, time, duration, and intensity. While no two user communities have communications needs that are identical, there are common characteristics in their specific requirements -- interoperability, flexibility, global coverage, security, and assured access.

b. Access to SATCOM services is the most fundamental need of the warfighter. Deployed and mobile warfighters are largely dependent on SATCOM to satisfy their information transfer needs. Warfighters rely on SATCOM to maintain situational awareness, to exercise positive command and control, and to collect and disseminate intelligence, warning, and target acquisition information. Unified Combatant Commanders have repeatedly requested the ability to access SATCOM on demand and to control the resources apportioned to them by the Joint Chiefs of Staff. A warfighter’s access to SATCOM support must be available on demand when and where needed for the duration on the mission. Such access allows the joint warfighter to collect and disseminate intelligence and orders rapidly. This rapid transfer of information enables us to operate inside the enemy’s decision cycle and retain the initiative.

c. Army Force XXI doctrine centers on a power projection Army deploying "tailor-made" force packages from CONUS sustaining bases to trouble spots worldwide. These force packages will be small, very versatile, and capable of fast, decisive victory with minimal casualties and collateral damage. Recent deployment trends indicate that force packages will be composed of elements from all services. Communications between deployed forces in theater and their sustaining base are possible with SATCOM. Mobility is key. The commander must be able to synchronize his forces and communicate his intent to subordinates while he is on the move.

d. The Army is basing future SATCOM developments on the following assumptions:

  1. Over the extended battlefield and particularly for split-based operations, SATCOM will be the preferred means of communications.
  2. SATCOM ground terminals must be manpackable, mobile, multiband, fast to set up and communicate, secure, durable, and as light as possible.
  3. SATCOM must provide the warfighter with seamless worldwide communications media for secure high quality voice, data, graphics, still/full motion video, and imagery.
  4. SATCOM will be employed at all echelons and by all types of units.
  5. Whenever possible and practical, commercial SATCOM will be used to augment military SATCOM.
  6. The Army will encourage and exploit the development of commercial SATCOM ground terminals and the capabilities they possess. The best commercial standards will be adopted when possible.

e. Military satellite communication systems include the Defense Satellite Communications System (DSCS), Military Strategic and Tactical Relay Satellite EHF (MILSTAR), and Tactical Satellite Communications (TACSAT) systems. All three types are considered to be priority capability enablers. Other modernization efforts described include Global Broadcast Service (GBS) and the Global Positioning System (GPS). GBS provides tailored, multi-media, intelligence broadcast service for Army XXI commanders and their staffs, while GPS remains the Army’s primary navigational aid.

f. Current Department of Defense owned and operated satellite communications systems have finite lives. Within the next ten to fifteen years, the existing resources of the DoD SATCOM architecture will require replenishment. More importantly, the current systems do not possess the requisite capabilities to support the information demands of the future warfighting environment. The pressures of growing warfighter information requirements against degrading satellite transport systems have been recognized. Recent studies and analyses have begun the process to recommend and select a future architecture that balances warfighter communications needs against programmatic, funding, and technological constraints.

5.2 Space Segment Capabilities.

a. No single space segment asset can satisfy all the needs of the warfighter. WIN and Force XXI will use a variety of space segment assets for communications. Each space segment and the frequency band offers advantages and disadvantages to the warfighter. The UHF band offers single channel assess at low data rates (16 Kb/s or less) with no anti-jam (AJ) capability but is characterized by small, inexpensive ground terminals. The UHF band also allows for the implementation of Demand Assigned Multiple Access (DAMA). SHF offers greater throughput for users, but provides limited protection for the warfighter. Competition for SHF band access is increasing, making access authorization difficult to obtain. The Milstar program provides the newest space segment. Milstar EHF provides well-protected communications for the warfighter by using Low Probability of Intercept (LPI) and Low Probability of Detection (LPD) technologies combined with AJ capabilities. Commercial SATCOM, utilizing portions of the SHF band, provides surge capability when military systems are saturated. A proper mix of military and commercial satellite systems are necessary to meet the requirements of a force projection Army. This mix will balance the capabilities and limitations of the various assets (figure 5-1).

Figure 5-1. Space Segment Capabilities

5.3 Army Single Channel SATCOM Architecture.

a. Single channel SATCOM is primarily low data rate communications, i.e. 16 Kb/s or less. Single channel space and ground terminal segments are characterized by increased terminal availability, low cost and ease of mobility. It can network with multiple users, communicate on the move, and can penetrate foliage while on the ground. However, UHF single channel SATCOM access is extremely restricted, has limited information throughput, and has no anti-jam capability.

b. The warfighter must have the freedom and flexibility to move quickly on the battlefield and not be hindered by heavy cumbersome terminals. Ultimately, a terminal that is small, lightweight and could allow communications on-the-move, paging capability, with hands free operation is desired. Technology is moving quickly towards making that a reality.

5.3.1 AN/PSC-5 SPITFIRE.. The AN/PSC-5, SPITFIRE, is the Army’s newest single channel SATCOM terminal. It provides DAMA and Narrowband Secure Voice capability. The implementation of DAMA will increase access and throughput for the warfighter. The SPITFIRE has embedded COMSEC and TRANSEC and weighs less than twelve pounds.

5.3.2 AN/PSC-11 SCAMP. The Army has initiated a program to develop and deploy manpack terminals that will operate over the military’s newest constellation, MILSTAR, in the EHF frequency band. The AN/PSC-11, Single Channel Advanced Manportable Terminal (SCAMP) provides secure anti-jam protection, lower probability of intercept and lower probability of detection. SCAMP will be developed and fielded in two phases, or blocks.

a. SCAMP - Block I has embedded COMSEC/TRANSEC and provides EMP protection with a biological/chemical protected carrying case. It provides range extension interfacing with the Area Common User System (ACUS) and Combat Net Radio (CNR). The SCAMP - Block I will be a manportable single channel, terminal offering half duplex communications using today’s technologies.

b. SCAMP - Block II will transmit and receive low rate data and voice in selectable point-to-point or broadcast modes. It will transmit in the EHF band and receive in the SHF band. It will also have paging capability. The SCAMP - Block II will be manpackable (12-15 pounds) and will be developed using emerging technologies.

5.4 Army Multichannel SATCOM Architecture.

a. The Army, Marine Corps and Joint Communications Support Element (JCSE) currently employ the AN/TSC-85B/93B (V)1, AN/TSC-86, and the AN/GSC-49 satellite terminals. The Air Force currently employs the AN/TSC-85B/93B (V)2, and AN/TSC-94B/100B satellite terminals. These TACSAT systems are used to meet most tactical multichannel range extension communications requirements of the Joint Service. The life expectancies of these systems have been continually extended over the years as systematic product improvements were made. However, these systems are rapidly becoming obsolete and will approach the end of their planned life cycle by FY 2001.

b. The current series of multichannel TACSAT terminals operate in a hub and spoke configuration using eight foot or twenty foot antennas. The hub and spoke configuration usually consists of an AN/TSC-85B terminal serving as the hub with up to four AN/TSC-93B terminals serving as spokes. Data is transmitted from the AN/TSC-93B to the AN/TSC-85B. The AN/TSC-85B relays the data to a tactical switch or Standard Tactical Entry Point (STEP). Drawbacks to this configuration are: inefficient use of available satellite capacity, limited throughput and lack of operational flexibility.

c. Multichannel TACSAT terminals and DSCS satellites operate in the military portion of the SHF X band (7.25 to 8.4 gigahertz (GHz)). Currently employed TACSAT terminals can not use the SHF commercial C band (3.7 to 6.4 GHz), and Ku band (11.4 to 14.5 GHz).

d. Current TACSAT terminal systems and associated DSCS satellite systems are unable to handle the current demand for substantially increased voice, data, video, and imagery traffic (split based operations). Because of their size and weight, TACSAT terminals lack adequate strategic transportability and tactical mobility. Despite these shortcomings, Army multichannel TACSAT terminals provide range extension connectivity during deployments, crisis response, contingency situations, and other national emergencies/commitments.

e. As the scale and complexity of Army operations increase to include peace operations, humanitarian assistance, and operations in aid of civil authorities, so does the importance of logistics to the success of these operations. The currently fielded family of multichannel TACSAT systems and DSCS satellites cannot support the large volume of C4I data required for split based operations.

f. The primary objective of WIN multichannel TACSAT objective is to remedy technological obsolescence, increase throughput, provide multiple paths, reduce maintenance downtime, reduce size, and enhance mission performance through modernization of the Army's multichannel TACSAT capability. This requirement will also drive the design for the next generation of military SHF satellites to include features that will support disadvantaged multichannel TACSAT terminals (small antennas, low transmit power). Current systems require the use of dedicated facilities to control satellite access. This control effort is currently performed by Ground Mobile Forces (GMF) control. Proposed capabilities for future systems may reduce or eliminate the requirement for GMF control all together. This would alleviate the control and access deficiencies experienced in Operation Desert Shield/Storm.

g. A rapid, reliable, state-of-the-art, Tri-band TACSAT communications capability is vital to bridge the widening gap between deployed forces and the power projection platform. The currently fielded multichannel tactical satellite ground terminals (AN/TSC-85 and AN/TSC-93) will be replaced by the SHF Tri-Band Advanced Range-extension Terminal (STAR-T) and the EHF Secure Mobile Anti-Jam Reliable Tactical Terminal (SMART-T).

5.4.1 SHF Tri-Band Advanced Range-extension Terminal (STAR-T).

a. The STAR-T is under development as the replacement for the current Army multichannel tactical ground terminals, AN/TSC-85 and AN/TSC-93, at Echelons Above Corps (EAC). Assuming multilevel security (MLS) is in place at EAC, the STAR-T will also replace EAC TROJAN SPIRIT II terminals. The increased trunking capability added by STAR-T will significantly improve the Army's operational capability by expanding the efficiency and capacity of the WIN and reducing terminal size and maintenance costs of currently fielded systems.

b. The STAR-T will be HMMWV mounted and C-130 roll-on/off capable. It will operate over military and commercial SHF satellites and will provide range extension for both commercial and military switching systems. The terminal will provide data, imagery, and voice communications at various data rates up to four T1 or E1 (2.048 Mb/s) circuits per trunk group for a total aggregate data rate of 8.192 Mb/s.

c. There will be two versions of the STAR-T; a standard version and a switched version. The switched version will contain an embedded switch capable of terminating 35 local subscribers. Follow-on ancillary equipment will allow the switch to terminate up to 280 subscribers. The standard version will not have an embedded switch,. It will be configured at a later date to allow the switch to be installed if necessary.

d. STAR-T will provide communications connectivity for split based operations between the theater and the sustaining base. DSCS SHF satellites will be used as much as possible to provide anti-jam protected links for all users. If current and future DSCS satellites cannot provide the total required throughput, then selected links will use commercial satellites to satisfy the requirement. The determination will be based on location of the terminal in theater, distant end location and type of traffic. The STAR-T will satisfy the connectivity requirements for the following requirements:

e. STAR-T will be employed as follows:

  1. Theater TACSAT companies will deploy up to twenty standard STAR-T's, which will replace AN/TSC-85B and AN/TSC-93B TACSAT terminals. These terminals will provide range extension connectivity between selected EAC node switches and key headquarters as METT-T needs dictate. Links will also be provided to the supported corps/deployed units for entry into the EAC switched network. Depending on the size of the deployment, a number of terminals will provide connectivity back to CONUS DSCS strategic terminals or commercial satellite interfaces for entry into the Defense Communications System (DCS). Links to other services, joint/allied headquarters, staging bases, and other locations will be provided based on METT-T. The terminals will operate in a mix of point-to-point and multi-node configuration. The multi-node capability will reduce the number of terminals required at nodes requiring multiple connectivity.
  2. An EAC signal battalion will deploy up to eight standard STAR-T's to augment EAC IEW communications requirements. These terminals will replace EAC TROJAN SPIRIT II terminals. They will provide connectivity between CONUS and within the deployed EAC area of operations that cannot be met by the EAC TACSAT company and associated switched network. The increased efficiency of the EAC switched network combined with MLS will reduce the number of terminals required to support this mission. This concept assumes MLS is in place at EAC by the time of fielding.
  3. The Power PAC3 (PP3) company will deploy up to thirteen STAR-Ts with embedded switching capability. These terminals will have an integrated switching capability unlike standard STAR-T's. The PP3 company will support Army contingency missions. In most deployments it will provide communications support for ARFOR Headquarters during initial entry into a theater. The PP3 company will also deploy up to six Liaison teams for supporting headquarters (joint, allied, etc.). As follow-on forces and EAC communications assets arrive in theater, the PP3 company may redeploy to support other missions. The PP3 company will have additional communications assets to include single channel TACSAT, High Frequency (HF) radios, and Line-of-Sight (LOS) systems. The switch carried by the PP3 STAR-T will support local subscribers as well as terminate transmission groups from LOS and other STAR-T's. The switch will significantly reduce the air frames required for initial entry/power projected missions. The PP3 terminals will be operated by a crew of three (two TACSAT (31S) and one switch (31F) operator(s)).

f. Satellite links between WIN switches will be at data rates of 1.544 Mb/s to 4.608 Mb/s. CONUS links will be from 1.554 Mb/s up to 8 Mb/s depending the throughput requirements. Links to adjacent units (allied, etc.) will normally be smaller than 1.544 Mb/s.

5.4.2 EHF Secure Mobile Anti-Jam Reliable Tactical Terminal (SMART-T).

a. The SMART-T is also under development. The SMART-T is a HMMWV mounted, MILSTAR SATCOM terminal that will provide multichannel range extension for WIN at division and corps It uses the new MILSTAR satellite communications system.

b.. The SMART-T operates at both the low (75 Bps to 2,400 Bps) and medium (4.8 Kb/s to 1.544 Mb/s) MILSTAR EHF data rates. It provides Low Probability of Intercept/Detection (LPI/D) and has built in Transmission Security (TRANSEC) with Over-The-Air-Rekeying (OTAR) capability. It has the capability to interface and control certain aspects of the satellite such as resource control and antenna pointing. The SMART-T must be initialized with TRANSEC fill data and mission specific data. SMART-T does not provide COMSEC, but accepts data encrypted by the user. Selected SMART-Ts will have embedded FSEN switches. The SMART-T is interoperable with MILSTAR, FLTSAT EHF Packages (FEP), and EHF Packages on UHF Follow-On (UFO) Satellites.

5.5 Global Broadcast Services.

a. The Global Broadcast Service (GBS) is an evolving secure, integrated satellite broadcast service and information dissemination system based on commercial and high technology developments. GBS increases the capacity and velocity of information distribution. As a component of the WIN, GBS augments current space and terrestrial transport systems through one-way transmission directly to the Warfighter.

b. GBS exploits commercial developments in the Direct-to-home Broadcast Service industry, i.e., DirecTV, DirecPC, PrimeStar. Direct-to-home Broadcast Service systems use compressed digital video technology and high-capacity satellite transponders to broadcast numerous channels of digital video, audio, and data to small inexpensive receivers. Because of their low cost, small size, and mobility, GBS will be fielded to tactical combat, combat support and combat service support units, at all command echelons, down to battalion level. The receiver terminals would consist of a small antenna system and a GBS receiver. GBS terminals would be capable of operating onboard aircraft, ships, and vehicles.

c. GBS provides state of the art multimedia broadcast services to enhance warfighter C2 capability. GBS provides a real time, continuous means to receive, access, retrieve, and archive battle command information. The information can come from national/strategic sources, or from tactical theater level. These information products can be video broadcasts, Unmanned Aerial Vehicle (UAV) video, Common Ground Station (CGS) sensor data, or other large volume data product. Some of the potential types of information available are:

d. GBS provides a tailorable information dissemination system for the warfighter. At each echelon the user can define the type of information he needs and when he needs it. Users at GBS terminals (e.g. the current Warfighter Associate) will set profiles that define the time, area, and type of information they want to receive through the GBS system. They can also submit queries/requests for specific data. These profiles and queries are sent through the deployed communications architecture to the Information Dissemination Server (IDS), located in the continental United States.

e. The IDS provides the information management capabilities for the GBS. It functions in conjunction with the user terminals to support specific user requests (warfighter pull) of data as well as the push of data. This push/pull relationship is based on user profiles (requests for certain types of data) (smart push) and scheduled broadcasts. The IDS manages data, stores it, and disseminates it to the uplink. It also has the functionality of searching, retrieving, and integrating data from multiple data sources. It places data in the local user repository to allow for rapid accessibility. As information comes into the IDS, the profiles are checked. If the data matches a specific profile, the information is sent to the uplink, and broadcast over GBS.

f.. GBS assists the Force XXI warfighter in dominating information operations. The implementation of a GBS has the potential for significantly increasing the coherency of battle command throughout the force. The ability to receive, access, archive, and retrieve battle command information such as high resolution maps, overlays, full motion video, audio, and data, enable key leaders throughout the force portray a coherent joint common picture. GBS improves force effectiveness, and significantly reduces the planning/decision/action cycle.

5.6 Airborne Communications Node.

a. The Airborne Communications Node (ACN) combines the capability of a high altitude endurance UAV with the essential capabilities of a state-of-the-art communications package (node). The ACN’s capability to self-deploy anywhere in the world will free up airlift assets that can be used for other missions. The ACN will carry robust communications packages that can be reconfigured rapidly to support changing C2 priorities. High gain antennas coupled with the ACN’s ability to loiter at very high altitudes (65,000 feet and higher) for extended periods of time will enable tactical users equipped with lightweight omnidirectional antennas and low powered radios to establish over-the-horizon communications from mobile platforms. This capability will provide a significant improvement in C2 on the move (C2OTM).

b. The ACN will be a uniquely capable platform for greatly improving battle command and battle management communications. The ACNs lift capacity will allow it to carry a large, multiband, multi-mode, robust communications payload to support a relatively large number of subscribers. Figure 5-2 shows some UAV programs that offer possible solutions to our ACN requirements. Some of the possible communications payloads are:

Figure 5-2. UAV Programs Offering Possible Airborne Communications Node Platforms

c. The capability to operate at high altitudes will provide a large communications footprint diameter of 250-400 miles (depending on ground systems deployed). Loiter endurance times of 24 to 96 hours or more will help ensure user access. A robust antenna and power suite will support the integration of leap ahead information and communications technology as it becomes available, without major modifications to the airframe, antennas, or power bus. The objective ACN will be fully modular, with a common power and signal bus and flexible antenna system. This will allow rapid reconfiguration between missions. See figure 5-3.

Figure 5-3. Objective ACN Communications Capabilities.

d. The Objective ACN System will provide communications capabilities to support existing joint and Army communications architectures, and to correct communications deficiencies identified during recent deployments and operations. The ACN capability should include:

  1. A modular communications node payload with gateway capability to support and interconnect a JTF, ARFOR, corps, or division that has both legacy and state of the art communications systems.
  2. A robust antenna system, versatile power suite, and modular communications package to support rapid reconfiguration on a mission by mission basis, as communications priorities change. All components on the ACN should be capable of integrating leap ahead technology as it becomes available.
  3. Range extension (retransmission) of SINCGARS, EPLRS, UHF surrogate satellite, MSE, and JTIDS, as well as a limited gateway capability between SINCGARS and UHF satellite.

(a). The ACN must be capable of performing retransmission for CNR/SINCGARS nets. An airborne gateway between SINCGARS and UHF Single Channel TACSAT will provide on-the-move capability for mobile platforms, without the need for high profile, directional auto-track TACSAT antennas.

(b). The JTIDS provides near-real-time air defense engagement operations information that must be accessible by air defense artillery (ADA) units during all phases of an operation. JTIDS relay capability will extend connectivity between widely dispersed ADA task force elements and the joint air battle players. The ACN will augment other JTIDS relay, including Airborne Warning and Control System (AWACS), in providing JTIDS range extension.

(c). EPLRS is used to broadcast situation awareness data. The relay will link enclaves that are beyond line of sight.

(d). MSE relay will connect widely dispersed signal nodes on the battlefield.

(4) Reach-back capability with digital cellular phones to support early entry and major offensive operations. (Cellular phone services may be limited because COTS cell sites are large and heavy, and there is at present no incentive for the commercial industry to downsize.) Reach-back communications will consist of a satellite link with minimum data rate of T1 (1.544 Mb/s).

(5) A Communications Control Element (CCE) capable of switching frequencies, hopsets, and crypto variables by remote control from the ground. An onboard capability will allow for preprogrammable frequencies, hopsets, and crypto variables as well as Over-The-Air Rekey (OTAR) of hopsets and crypto variables.

(6) Onboard Communications Manager/Controller (CMC) to increase the number of gateways to provide truly seamless connectivity to link users of dissimilar systems. The CMC is perhaps the most crucial capability for proper operation of the ACN. The CMC must perform the following functions:

  1. Ensure Inter-connectivity between/among all on-board communications services/equipment.
  2. Manage in flight service priorities, frequency assignment, net initialization, communications security (COMSEC) key assignment, antenna pointing, with input from ground-controllers of ACN.
  3. Be responsive (external to any resident control logic) to the ground controllers of the ACN payload, not to the airborne platform controllers.
  4. Dynamically access and reallocate unused communications channels on the ACN.
  5. Provide gateway connectivity and data format conversions for dissimilar joint radio systems (i.e., JTIDS to EPLRS, EPLRS to PLRS, Havequick II to EPLRS, etc.)

(7) Range extension for Army and joint video teleconferencing.

(8) LPI and LPD communications and store and forward e-mail for SOF and conventional elements that operate deep in enemy territory.

(9) GBS relay to provide broadcast communications on-the-move to support tactical users with omnidirectional antennas and low powered receivers. TMD and NBC warnings can be uplinked to the ACN and rebroadcast to miniature pagers on the ground.

(10) Flyaway transit case UAV Launch and Recovery (LRE) element. This miniaturized LRE can deploy early in a contingency operation, and allow in-theater mission controllers to direct the ACNs.

(11) Cross linking between multiple ACNs to cover an entire theater of operation.

(12) The ACN must operate in secure and nonsecure modes.

(13) The ACN must be technical architecture compliant to insure joint interoperability with joint and service objective architectures.

(14) The system must be compatible with WIN protocol and standards for switching and subscriber services.

e. As an essential part of WIN, the ACN contributes to the rapid connectivity of the entire network. The force projection capabilities of the ACN will greatly enhance the communications capabilities of the WIN architecture. The ACN will provide reach-back connectivity from the area of operations to sustaining bases. It will also provide gateways for seamless communications between dissimilar communications systems. The ACN will provide communications redundancy to ensure Force XXI information dominance, reduce the requirement for terrestrial line-of-sight radio relays, and provide new types of communications services directly to the warfighter.

f. Although the ACN augments commercial and military satellites, it does not replace them. Satellites and satellite radio systems operate in specific frequency bands and provide unique communications services to support WIN. Satellites, however, will not have the capability to support range extension for every type of military radio and communications system. Range extension for voice and data line of sight communications through the ACN will enhance the warfighter’s C2 capability.