Approval Date:

17 Jun 76



1.  STATEMENT OF THE REQUIREMENT. There is an urgent requirement within the Fleet Marine Force (FMF) for ultra high frequency (UHF) and super high frequency (SHF) tactical satellite-communication terminals. These terminals will provide entry into the tactical satellite-communications systems utilized by the Marine Corps. They will be sized to provide efficient utilization for echelons varying in size from special reconnaissance units to Marine Amphibious Force (MAF) Headquarters. The required initial operational capability (IOC) and fleet introductory date is FY79.


a.  Threat. Potential enemy threats confronting the United States in the near- to long-range period are described in Paragraph II (Global and Regional Appraisals) of the Marine Corps Long-Range Plan (MLRP) and the Marine Corps Mid-Range Objectives Plan (MMROP 74-83). These threats are described in terms of:

       (1) Potential enemies' growing combat capabilities,

       (2) Potential enemies' expanding technological capabilities,

       (3) Potential enemies' propensity for low-, mid-, and high intensity warfare.

To successfully counter predicted threats, the Marine Corps, as a force-in-readiness, must be capable of quick response, organized and tailored to the specific need. For the effective exercise of command in any degree of combat intensity, unit commanders must be provided with communications equipments that are time-ordered, secure, incorporate maximum antijam electronic counter-countermeasures (ECCM) circuitry, and capable of handling large volumes of information.

    b.  Operational Deficiencv. Currently, tactical communication systems do not adequately meet long-haul combat operational needs, especially in the area of amphibious operations. These tactical nets rely mostly on radios operating in the high frequency (HF) portion of the radio spectrum, which is becoming prohibitively saturated. In addition, frequency propagation is highly dependent on varying ionospheric layer ionization. At frequencies above HF, communications over long distances are line-of-sight limited and often require numerous relay and switching points in tactical trunk communications. This "indirect" communication introduces disruptions and delays that are incompatlble with the tempo of modern warfare. A family of ground terminals, both SHF and UHF, is required to provide the FMF a satellite-comn,unication capability to enhance and replace older multichannel radio equipment. Incorporation of tactical statellite communication terminals within the Marine Corps would significantly benefit Marine Air/Ground Task Force (MAGTF) units in the successful accomplishment of their assigned combat missions.


.   a.  Operational Concepts. The tactical satellite-communication terminals would be deployed with the Landing Force Commander (LFC) to provide long-haul and Defense Communication System (DCS) entry communications, as well as intra-landing-force communications where terrestrial radios could not provide the requisite communication links. Satellite terminals would give the LFC the capability of deploying a terminal to meet a specific operational need.

(1) A UHF manpack terminal would be available for low-echelon, highly mobile users, such as reconnaissance patrols, platoons, and company-size units operating independently.

(2) A SHF 1/4-ton vehicular terminal would be available for intermediate size units such as Marine Amphibious Units (MAUs) and Marine Amphibious Brigades (MABs), or at the Division, Wing, and Force Service Support Group (FSSG) Headquarters operating under circumstances where the use of radios (terrestral) is prohibited by transmission problems or tactical considerAti on.5

(3) A shelterized terminal would be available for large-size units (MAF/DIV/WING) requiring a satellite transmission capability. Two types of terminals are proposed. One type will be an SHF 1 1/4-ton vehicular terminal for intra-MAF bunking. The other type will be a UHF 1 1/4-ton vehicular terminal to provide the LFC with long-haul and DCS entry communications in conjunction with the Commander Amphibious Task Force (CATF)/(LFC) communication requirement.

b.  Organizational Concepts. The family of satellite terminals would be issued to the following units:

(1) Manpack Terminal: Force Reconnaissance Company; Reconnaissance Battalion, Infantry Division; Special Purpose Unit/mission.

(2) 1/4-Ton Vehicular Terminal: MAU, MAB, MAF Headquarters, (Force Comm Bn).

(3) Shelterized Terminal: MAU, MAB, MAF Headquarters (UHF), (Force Comm Bn); MAB, MAF Headquarters (SHF), (Force Comm Bn).


a.  The family of satellite terminal equipment will be used to augment current and planned communication systems. It will be used to increase the efficiency, capacity, and flexibility of current FMF communications systems. These small, lightweight terminals will be designed and human engineered to satisfy the requirements of all FMF units ranging in size and mobility from small, special purpose reconnaissance groups to MAF Headquarters. The terminals will be modular and designed for commonality and interchangeability of components amona the family of terminals.

b.  Four basic terminals are required to meet the requirements of the various echelons:

(1) Manpack. A manpack terminal for low-echelon, highly mobile units is required. The terminal with power source, antenna, and all necessary auxiliary equipment must be of size, weight, and configuration to be backpacked and operated by one man. A total weight of 40 pounds is acceptable, with a lesser weight desirable. The power source must have the capacity for a minimum of five days of typical operation. This terminal must provide at least one half-duplex secure communication voice channel (digital channel is acceptable). Transmitte' output will be the minimum required to provide reliable and totally compatible operation in all geographic, climatic, and environmental conditions. Setup and teardown time, if required, should not exceed five minutes

(2) Vehicular Terminal. A terminal that is designed for installation in a 1/4-ton tactical vehicle is required. This terminal must provide fat least one full-duplex secure voice channel capable of passing record, voice, and data traffic. The power source for this terminal will be provided by either the vehicle's power or an external power source. The terminal equipment must be capable of being removed from the vehicle for operation by no more than two men. Setup and teardown time should not exceed 30 minutes.

(3) UHF and SHF Shelterized Terminals. Two types of shelterized terminals designed for secure multichannel communications in the UHF and SHF ranges are required. These channels will be capable of passing voice, record, and data traffic. Terminal power will be provided by standard military 60 Hz alternating current generators. Terminals will be transported by 1 1/4-ton vehicles. Setup and teardown time should not exceed one hour. The shelter will be one of the Standard Family of Expeditionary Shelters to be determined by the Joint Steering Committee on Tactical Shelters, unless such shelter design is not compatible with equipment to be installed; in any event, the shelter will meet ISO requirements.

c.  All terminals will incorporate appropriate antijam (ECCM) circuitry or low-probability-of-intercept capabilities to deny or degrade a potential enemy's use of Signal Intelligence (SIGINT) and Electronic Warfare (EW).

d.  The operating frequencies of the satellite terminals will be compatible with those of the satellite repeaters. All of the terminals will be tunable over the entire bandwidth of the repeater. The terminal equipment will be operationally compatible with the electromagnetic environment encountered in MAGTF operations. Spurious electromagnetic emanations by the terminal equipment will be suppressed to have no significant effects on other equipment in the area and to minimize the effects of enemy electronic warfare efforts. In addition, the terminals will be designed to survive the electromagnetic pulse effect of a nuclear detonation or of another source.

e.  The satellite terminals must be human engineered to increase efficiency in operation, maintenance, setup/teardown, and personnel safety. A minimum number of personnel shall be required to set up and operate the terminals. They will be engineered so that their size, weight, and simplicity of operation and maintenance will meet the mobility requirements of the parent command.

Each of the terminals shall exhibit a combat availability of 0.995, where combat availability is defined as:

Availability = Total Uptime

Mission Profile Time under tactical field conditions. The mission profile is 90 days or 2,160 hours. Downtime must include all preventive maintenance as well as corrective maintenance. Maintenance, training, and logistic support should require no increase in personnel presently assigned to units receiving the equipment.


6.  RELATED EFFORT. Related developmental efforts currently being conducted are the AN/MSC-59 (Army) and AN/TSC-85 (Army) Satellite Communication Terminals; AN/TSC-89 (XN-1) (Marine Corps) Satellite Communication Central, Fleet Satellite Communication System; and the AN/PSC-( ) (Army) Manpack Satellite Communication Radio. Concurrently with the development of satellite terminals are Demand Assigned Multiple Access (DAMA) Modems.

DAMA is a method for allowing ground terminals to simultaneously share the same satellite repeater. Since DAMA is a time-coordinated system, each user is assigned a particular time slot for his burst of traffic, and all users share the satellite in a controlled time sequence. It is planned to phase DAMA subsystem in as a future refinement and improvement to the satellite terminals, which will initially employ a less desirable but operationally proven multiple access system known as Frequency Division Multiple Access(FDMA). Navy is developing a modem for use in the Fleet Satellite Communication System; Army is developing a modem for the Ground Mobile Forces System.


a. Technical Feasibility. The feasibility of each of the terminals has been demonstrated during the Joint Tactical Satellite Communications (TACSATCOM) Program or through subsequent terminal developments/improvements by the Army and the Navy. In all cases, except for the manpack terminal, prototype terminals have been delivered and are being tested which will meet all essential requirements. The manpack terminal prototype is due for delivery during FY76 with very little risk involved.

b. Cost Forecast. Production cost estimates for each of the terminals, based on current terminal developments are as follows:

(1) Manpack UHF (AN/PSC-( )) $ 36,000
(2) 1/4-Ton SHF (AN/MSC-59)  $390,000
(3) 1 1/4-Ton SHF (AN/TSC-85)$890,000
(4) 1 1/4-Ton UHF (AN/TSC-89)$200,000