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[] AWST 21.1.02: U.S. Military Wants Sweeping Satcom Changes,

Aviation Week & Space Technology
January 21, 2002
Pg. 27

U.S. Military Wants Sweeping Satcom Changes

Even with new Milstar crosslinks, U.S. programs will be forced to retool for mobile coalition warfare 

By Craig Covault, Cape Canaveral

The U.S. military services, along with the National Reconnaissance Office, NASA and industry, are embarking on a major transformation of the U.S. military communications satellite network. 

The objective is to make the system--with its numerous programs, dozens of spacecraft and thousands of terminals--far more responsive to the highly mobile combined-force coalition warfare--undertaken in Afghanistan and planned for other locations--in response to the Sept. 11 attacks. Military lessons from Kosovo are another key impetus.

"We have reached the limits of what we can do with the satellite communications architecture that we have today," said Christine M. Anderson, program director for the Milsatcom Joint Program Office at the USAF Space and Missile Systems Center in Los Angeles.

"We are now fighting a different kind of war and our military communications architecture needs to take that into account," Anderson told Aviation Week & Space Technology.

The overall U.S. military communications satellite network is literally the "central nervous system" for global Defense Dept. operations. But among the various services there are about seven major satellite programs with more than two dozen spacecraft (operating or planned) that are accessed by literally thousands of small ground terminals with different bandwidth and frequency capabilities.

The programs include the workhorse Defense Satellite Communications System (DSCS), Milstar, UHF Follow-ons, NRO relays, NASA TDRSS spacecraft and the coming Advanced EHF and Wideband Gapfiller programs.

The problem is that these programs are currently too often "stovepipe" systems less structured to support new fast-reaction mobile strike forces relying on systems like unmanned aerial vehicles (UAVs). 

"The way we are fighting today is different [from the existing architecture]," Anderson said. The new warfare "is with combined U.S. forces, local coalition forces and international forces." She said that a smooth communications interface is increasingly needed between such divergent units, but not necessarily possible with today's spacecraft and ground terminals.

"A leap in capability is required to meet the rapidly increasing demand for bandwidth and connectivity," said Air Force Space Command's initial announcement to industry on the new "Transformational Communications" initiative being implemented to solve the problem.

Edward C. (Pete) Aldridge, Jr., undersecretary of Defense for acquisition, technology and logistics, kicked off the initiative late last year. He has placed the transformation effort on a fast track, calling for initial study ideas by about June, with hopes that initial projects--involving either existing or new spacecraft, or ground elements--could be started by midsummer. Funding in 2003 has already been reserved to kick off the effort, Anderson said.

Seven teams involving all the services, NRO and NASA, as well as military-satellite users, have begun meeting under the auspices of the National Security Space Architecture Office to determine which direction to vector early efforts.

INDUSTRY HAS been asked to submit concepts by Feb. 11. Two companies will then be picked, by Mar. 1, to lead four months of trade studies that will feed information to the government teams.

The results of these government/industry efforts will shift the course of billions of dollars in military space communications planning for years to come.

The effort will also bring NASA in as a more active player in military communications satellite technology development, and is likely to result in the integration of communications services that serve NASA, NRO and the Defense Dept. The transformation program will also assess how the military services can better make use of civilian communications spacecraft.

A key goal will be to begin by modifying existing systems and software so military forces can send and receive information through terminals as small as laptop computers linked to a mix of satellite systems. Today, most military communication routes are tied to specific satellite networks like Milstar or DSCS.

"Today we have more mobile forces and you do not want to be carrying 2-4 different terminals to be talking to 2-4 different satellites," said Manuel DePonte, general manager of the Milsatcom Div. at the Aerospace Corp.

The idea will be to give users more capability with the existing systems, while new spacecraft and ground terminals will be built with this broader function. Substantially increased development of laser communications to achieve hundreds of gigabits per second will also be a priority.

In the mid-1980s, USAF tried, without success, to develop an operational lasercom system to link Defense Support Program missile warning satellites. But the new NRO GeoLITE spacecraft launched last May is demonstrating new lasercom capabilities important to elements of the transformation effort ( AW&ST May 14, 2001, p. 76).

The data rates possible with lasercom would also be especially important in commanding and obtaining intelligence from UAVs, said DePonte.

"There are currently no UAV links to Milstar and DSCS satellites," he said. There are plans to provide radio links under the Wideband Gapfiller program, and future lasercom programs would greatly enhance UAV operations.

THE INITIATIVE is beginning just as the U.S. has achieved a major military space communications objective--the establishment of a fully crosslinked Milstar communications-satellite network. "This is a very significant event," Anderson said.

The 10,000-lb. USAF/Lockheed Martin Milstar II--launched here at 7:30 p.m. EST Jan. 15 on board a Titan 4B/Centaur--will eventually be parked in geosynchronous orbit south of Europe.

The mission was led by the 45th Space Wing's 3rd Space Launch Sqdn. (SLS) which achieved a record 162-day flow to achieve the date set months ago, said USAF Lt. Col. Dave Jones, commander of the 3rd SLS. The overall cost of the flight is $1.25 billion, one of the more expensive USAF space missions.

About $800 million of that goes for the new 116-X-51-ft. Milstar. It will form--with three other Milstars already aloft--a global jam-resistant system where each spacecraft can relay its communications traffic to its sister satellites to the east and west.

AS THE SECOND advanced Milstar II version, the new satellite will also increase the ability of small ground, sea or airborne units--perhaps separated by just a few miles--to exchange encrypted voice, television, imagery and data, at rates up to 1.54 Mbps. using the same satellite. The spacecraft also carries a new TRW Consolidated Agile Beam Antenna to replace five earlier vintage antennas on the spacecraft's 2,400-bps. data-rate system.

The new Milstar will allow the overall constellation to support forces around the world, and to be controlled, without the need to bounce information through multiple ground stations.

"The protected communications capability now provided by the crosslinked Milstar system plays significantly with the modernization plans of all the military services," said USAFCapt. Patrick Youngson, chief of Milsatcom Operations at Air Force Space Command.

Milstar modernization has led to striking improvements. For example, the two older Milstar I versions could take an hour to transmit a 1.1-MB air-tasking order while the just-launched Block II can do the same job in 5 sec. Annotated 24-MB intelligence images, which can take 22.2 hr. to transmit on Milstar I, can be transmitted in 2 min. by the Milstar II--and just 24 sec. via the Advanced EHF to come online in 2006.

Anderson, who is on the Transformation Communications steering committee, said the long-term program should involve a "network-centric" architecture that would span many years of effort.

Existing programs will be part of it. "You can't just say 'give me a trillion dollars and we will change all the existing terminals,'" she said. "We have to determine how to get started with the spacecraft and terminals we already have."

FOR EXAMPLE, the DSCS program which had its first launch in 1982 needs to benefit, DePonte said. DSCS still operates five primary spacecraft, with two additional upgraded satellites to be launched in late 2002 and early 2003. Five others still function in orbit as residual satellites. Anderson said some of the major questions the new effort has begun to address are:

*How will crosslinks be established between various user communities?

*Do you need combined capabilities on 20,000-lb. satellites--twice the size of Milstar--or smaller satellites, possibly operating in clusters?

*How should strategic users be supported relative to tactical users?

*How much will all of this cost?

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