TSM update

TSM-Satellite Communications

Replacement subsystem

Communications-Electronics Command’s acquisition center at Fort Monmouth, N.J., awarded contract DAAB07-00-C-A261 June 21 to ITT Industries’ System Division (formerly Stanford Telecom in December 1999), located at Colorado Springs, Colo. The contract supports the project manager for defense communications and Army transmission systems, and it provides for replacing the current Defense Satellite Communications System frequency-division multiple access control subsystem with a less manpower-intensive system.

Maintaining DFCS has been threatened by diminishing vendor support for certain components, so an open-systems architecture with maximum use of commercial-off-the-shelf components was required to eliminate vendor dependencies and to take advantage of technological improvements in the commercial sector. Replacement DFCS will provide positive control and management of Defense Department, allied and government C-, X-,Ku- and Ka-band super-high-frequency FDMA SATCOM links accessing DSCS, Gapfiller, advanced wideband system, allied and government-leased commercial satellite transponders. RDFCS will control links defined by an external subsystem; that is, RDFCS doesn’t develop the FDMA link plan.

One of RDFCS’ key features will be the capability to perform power control on links under its purview, thus ensuring efficient use of transponder power while maintaining the required quality of service. RDFCS will be an integrated subsystem of the objective DSCS operations-control system. RDFCS will also be integrated into earth terminals under the DSCS operation center’s control. RDFCS will be operated by controllers at DSCSOCs and by ET operators. RDFCS consists of a network-control terminal, alternate NCT and network-terminal configurations. RDFCS will be fully integrated with DSCSOC-distributed computing architecture under development called ODOCS, and also with the host ET.

This is a 10-year firm fixed price/firm fixed price with economic price adjustment and time and materials contract for the initial development, fabrication and test of the RDFCS system, with options for RDFCS production units and training and maintenance support. Base-year effort funds obligated totaled $21 million, with initial systems being delivered three years after award. The total evaluated value of the contract is $63 million.

Point of contact is Frank Stein, steinf@gordon.army.mil, DSN 780-7903.

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Selective availability is zero

Per presidential directive, Global Positioning System’s control has set the selective availability error level to zero. This change means that all commercial receivers now have accuracy similar to keyed military receivers.

What does this mean for military users? According to the project manager for GPS newsletter (May 2000 Pathfinder): "First, the rationale for eliminating the intentional degradation of the GPS signal is to improve the accuracy available to civil users. This benefits many commercial GPS applications, including air, road, marine and rail navigation, telecommunications and emergency responses. Note these are all peacetime activities. Second and more important to the military user, the President’s statement made clear that the Defense Department retains the ability to selectively deny GPS signals on a regional basis when our national security is threatened. This means it’s more critical than ever that military users operate only with PPS-rated receivers, capable of operating under intentional signal degradation and other forms of hostile signal interference.

"This doesn’t mean that military users can now buy commercial GPS, nor does it mean you can operate without communications-security-keyed precision lightweight GPS receivers," the newsletter continued. "Your operational readiness depends on having PPS-rated military GPS receivers that will perform under hostile conditions!"

Also, a PM-GPS engineer conducted an informal test to compare the accuracy of a keyed and unkeyed PLGR. The informal test’s results indicated that the keyed PLGR achieved better accuracy and better signal strength than the unkeyed PLGR in both a benign and challenged environment.

POC is Russell Gambrell, DSN 780-7901.

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Extremely-high-frequency SATCOM

The Joint Requirements Oversight Council again validated the user community’s need March 23 for mitigating the loss of Milstar Flight 3. Flight 3, launched in April 1999, was equipped with the first medium-data-rate communications payload, which was designed to support the secure mobile antijam reliable tactical terminals performing mobile-subscriber-equipment range-extension missions at corps and division level. There was a misfire in the rocket’s upper stage, causing Flight 3 to fail to reach a useable orbit.

Since there were a number of options to mitigate Flight 3’s loss, Dr. J.S. Gansler, undersecretary of defense for acquisition and technology, signed the acquisition decision memorandum April 6 for the advanced extremely-high-frequency program. The ADM eliminated competition in the AEHF program and created a national team made up of Lockheed Martin, Hughes and TRW. This revised approach will provide a "Pathfinder" AEHF satellite on an accelerated schedule. Gansler’s guidance stated that Pathfinder will meet AEHF threshold requirements at a minimum and that satellites two to five will exceed threshold requirements.

Pathfinder is expected to launch around December 2004.

POC is Steve Churm, churms@gordon.army.mil, DSN 780-3418.

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New satellite for military

A review for proposal for a new commercial-like satellite that will augment DSCS was released to industry in June. The wideband Gapfiller system will provide the warfighter high-capacity X-band service compatible with DSCS; Ka-Band Global Broadcast Service compatible to what’s hosted on the ultra-high-frequency follow-on satellites; and a new two-way military Ka-band capability.

The WGS will be composed of space, control and terminal segments. The space segment is projected to consist of three Gapfiller satellites that will provide at least three times the throughput of the existing DSCS III satellites. Platform telemetry, tracking and control will be accomplished by the Air Force, while the Army will manage payload configuration and control using the Gapfiller satellite-configuration-control element. The terminal segment will consist of existing and modified X-band terminals, existing and programmed GBS terminals and the new two-way Ka-band terminals.

First launch is currently scheduled for the fourth quarter of 2003.

POC is Dale Sleeper, sleeperd@gordon.army.mil, DSN 780-7917.

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Warfighter to get more communications services

The Defense Department is working on the Teleport program, which will provide the deployed warfighter increased access to the Defense Information Services Network. Teleport’s goal is to provide a seamless connectivity into DISN using existing and programmed ground terminals, terrestrial transmission, switching, routing and cryptographic equipment.

The warfighter will access Teleport through the C, X, Ka, Ku, UHF and EHF satellite constellations where communications can either be crossbanded or sent directly into DISN. The planned architecture will allow the warfighter to access at least two Teleports from almost any geographical position worldwide.

Teleport connectivity could begin as early as 2002.

POC is Dale Sleeper, sleeperd@gordon.army.mil, DSN 780-7917.

Acronym QuickScan
ADM – acquisition decision memorandum
AEHF – advanced extremely high frequency (program)
DFCS – Defense Satellite Communications System f(requency-division multiple access) control subsystem
DISN – Defense Information Services Network
DSCS – Defense Satellite Communications System
DSCSOC – Defense Satellite Communications System operation center
EHF – extremely high frequency
ET – earth terminal
FDMA – frequency-division multiple access
GBS – Global Broadcast Service
GPS – Global Positioning System
NCT – network-control terminal
ODOCS – objective D(efense Satellite Communications System) operations-control system
PLGR – precision lightweight G(lobal Positioning System) receiver
PM – project manager
POC – point of contact
RDFCS – replacement Defense Satellite Communications System f(requency-division multiple access) control subsystem
SATCOM – satellite communications
UHF – ultra-high frequency
WGS – wideband Gapfiller system

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