Front-Line Satellites
NEW TECHNOLOGIES BRING CONFIGURABLE COMMUNICATIONS AND SURVEILLANCE CAPABILITIES TO TACTICAL OPERATIONS.
As ongoing operations in Iraq focus on cleaning out pockets of insurgency, neighborhood by neighborhood, street by street, a set of satellite communications technologies now being tested by the Department of Defense could benefit these and similar future operations by providing maneuverable and configurable surveillance and reconnaissance assets.
Field commanders would be able to call in surveillance, by targeting flexible, low-cost, tactical satellites on their next area of operation. More than that, they would be able to order up satellites with capabilities configured to the requirements of the mission, almost like ordering a laptop computer online.
The goal of DoD’s Tactical Satellite 3 (TacSat-3) program is to demonstrate the feasibility of the Pentagon’s “responsive space” vision: to give field commanders flexible options for obtaining real-time tactical surveillance data from space. Responsive space calls for satellites to be maneuvered into position quickly and kept at the ready for deployment as needed.
Tacsat-3’s plug-and-play architecture integrates payload with spacecraft, enabling its capabilities to be configured and reconfigured for specific and changing mission requirements. Upon demand, they would be rapidly assembled and configured, then launched into low earth orbit, 200 miles overhead. TacSat-3 was scheduled for a test launch late this summer.
There are also other ongoing efforts to enhance the military’s tactical sat-ellite capabilities. Telecommunications experts are developing hardware and software that will squeeze the last drop out of increasingly constrained bandwidth. Internet Protocol routers are being launched on satellites to make field communications quicker and more efficient. And satellite ground stations are being made smaller and lighter in order to enable satellite communications on the move.
“The military increasingly wants to deploy assured communications into areas of operations on demand,” commented Rick Sanford, director of global space initiatives at Cisco Systems. “They want satellite communications capabilities to support military requirements as they change. Demand in this area is growing in order to satisfy requirements in different areas of operations around the world, not only armed conflict, but also humanitarian relief and disaster recovery.”
Meanwhile, in Iraq, warfighters are struggling for access to communications bandwidth, according to Sanford. “The concept is to get smaller payloads and satellites up to provide more agility in more locations.”
“We want to give the guys in Baghdad access to their own satellite resources instead of having them rely on national assets” for surveillance and comm-unications, said Tom Chrien, an engineering fellow at Raytheon, the TacSat-3 lead system integrator.
RAPID REACTION
The TacSat-3 program began to tackle the problem of providing low-cost, flexible and reconfigurable satellites in 2004. “The concept of operations document put out by the U.S. Strategic Command on this topic calls for a new generation of rapid reaction satellites that can reconstitute capabilities lost due to unforeseen events,” explained Peter Wegner, TacSat program manager at the Air Force Research Laboratory
Key to the TacSat-3’s configurability feature is a plug-and-play electronic architecture similar to today’s laptop computers. “Laptops have USB ports and you can plug in new complex devices, “Wegner noted. “That is what we were trying to achieve with TacSat-3.”
A testbed to develop just such a capability was begun in 2005, and by mid-2006 a first-generation plug-and-play satellite had been developed and its capabilities tested on the ground. Those same capabilities will be tested in space once TacSat-3 is launched.
“Ultimately what we are hoping to achieve is to have a series of plug-and-play components, so that when urgent calls come in, we can reach into our stockpile and rapidly assemble spacecraft to meet mission needs,” said Wegner. “We intend to be able to provide everything from traditional ISR to tactical command and control to space situational awareness.”
Configuring satellites to meet mission needs will require decisions about the proper radio, payload, information collector, data cache and onboard data processor, and then assembling the spacecraft based on that analysis.
Eventually, TacSat-3 will be organized along a three-tier architecture. The first tier will include capabilities that are already in orbit. The goal here will be to maneuver satellites into position in a matter of minutes to a matter of days in order to satisfy mission needs. The second tier includes capabilities that have already been developed on the ground but which have not yet been launched into space. Tier two will provide capabilities to commanders by configuring and launching a satellite designed to meet mission requirements within a matter of weeks. The third tier will include those capabilities not yet readily available, with the goal of developing and launching them in less than a year.
TacSat-3 envisions deployment of a satellite bearing a payload called the Advanced Responsive Tactically Effective Military Imaging Spectrometer (ARTEMIS). ARTEMIS makes use of COTS components and industry standard interfaces, and its payload covers the visible through short-wave infrared spectrum.
ARTEMIS components include a high-resolution panchromatic imager, telescope, optics, focal plane array and control/readout electronics. ARTEMIS will also enable field commanders to access the intelligence data collected in near-real time, reducing response time and enhancing battle assessment. The system’s hyperspectral imager is designed to detect and identify threats on the ground and to see otherwise hidden targets.
ARTEMIS’ hyperspectral imaging sensor marks a qualitative change in how reconnaissance imagery has been developed and analyzed since the Civil War, according to Chrien. “During the Civil War, observers in balloons took pictures of the battlefield with cameras. Later, cameras were installed on aircraft and on satellites to provide warfighters with much the same type of intelligence.”
Photographs, taken from whatever vantage point and from whatever platform, require human intervention to view and interpret the image, Chrien continued. “This is a very visual process. The analyst must be able to recognize the shape of objects and to do that requires enough spatial resolution as well as contrast with the background.”
Hyperspectral imaging marks a departure from this technique because the process identifies the molecular content of the object. “There is no way to mimic or camouflage an item from this type of imaging,” he said.
SQUEEZING BANDWIDTH
While ARTEMIS marks an enhancement to satellite imaging capabilities, other developments in the works are concentrating on other aspects of tactical satellite capabilities. “Our big focus now is to squeeze every ounce of efficiency we can to satisfy the military’s demand for bandwidth,” said Greg Handermann, vice president of engineering at Comtech Mobile Datacom. “DoD is looking for higher bandwidth to get more types of data through to individual soldiers. This takes efficient signaling techniques to be deployed to make the maximum use of satellite bandwidth.”
Comtech is in the process of creating secondgeneration hub equipment that uses far more sophisticated algorithms for processing bandwidth. “This requires increased computational horsepower that is now available but wasn’t 10 years ago,” Handermann noted.
Once deployed, the Comtech innovation will allow more satellite users to communicate on a single channel. “Satellite communications can be deployed to more users without buying additional satellite channels,” Handermann said, noting that this could allow the military to put satellite communications equipment on more vehicles.
Cisco is increasingly focusing its attention on lower orbit and geostationary satellites, according to Sanford. The company is a partner in a DoD project called Internet Routing in Space (IRIS). The idea is to allow direct access to a network via satellite for faster and more flexible communications than current connections.
The Pentagon is partially funding an experimental IRIS satellite, which is scheduled to launch during the first quarter of 2009, and will have exclusive access to the satellite for the first year. Thereafter, Cisco and its partners may make the service available commercially.
“The primary function of IRIS is to enable the ability to communicate in theater and to network in space,” Sanford explained. “The concept is to facilitate applications and communications directly to areas of operations. This will allow the military to increase user capacity by eight to 10 times.”
Currently, sending information from one remote user to another via satellite requires the first terminal to bounce data off the satellite and back to a ground station for routing. The ground station retransmits it on a different frequency to the satellite, which then sends it to the intended destination. A router payload on a satellite, on the other hand, can immediately select a channel to send information where it needs to go, thereby increasing transmission times by eliminating the extra round-trip to and from the ground station.
IRIS also foreshadows capabilities to be incorporated into the Air Force’s Transformational Communications Satellite (TSAT) program. TSAT is intended to use routers and lasers to provide mobile and fixed users up to 100 times the bandwidth of the MILSTAR communications satellites currently in use. Cisco is part of a team led by Boeing that is bidding on TSAT.
TSAT, which is scheduled to launch in 2016 or 2017, “is intended to be a massive backbone network in space,” Sanford noted.
Meanwhile Iridium Satellite, which is best known for operating a constellation of 66 communications satellites that carry voice communications, carries 75 percent of its DoD communications traffic into and out of the Middle East, noted Scott Scheimreif, Iridium’s assistant vice president for government programs. The company is working with other technology providers to integrate their offerings and provide tracking of military personnel and materiel in Southwest Asia.
The Marine Corps is employing devices that combine Iridium satellite communications with radio frequency identifications tags and Web-based tracking software to provide real-time personnel visibility. “Twenty-four months ago, the Marine Corps and DoD had limited realtime visibility regarding the status of the injured warfighter,” Scheimreif said.
The system incorporates short burst data applications from Iridium, together with RFID tags and additional software, to provide rapid casualty identification, visibility and status. The casualty tracking system transmits data to Iridium’s network of low-earth orbiting satellites to relay real-time data on the location and condition of injured personnel.
PORTABLE DEPLOYMENT
Iridium also provides satellite links for a mobile system that uses RFID to track movement of Marine Corps military supplies. The materiel tracking system employs low-power radio transmitters in the form of RFID tags attached to equipment, pallets and containers, which contain up to 128 kilobytes of supply-chain data. The tags are read by interrogator devices set up near the entrances to bases and supply hubs. Portable Iridium terminals transmit the data to an Internet- based tracking system. Commanders can determine the location and status of a shipment by logging onto a Website.
The portable Iridium terminal, known as the Portable Deployment Kit (PDK), and co-developed with Savi Technology and NAL Research, is designed to address the challenge of extending supply-chain visibility directly into the area of operations, where there is no infrastructure of fixed RFID readers. The PDK integrates several automatic identification and data collection technologies, such as bar codes, RFID, GPS positioning and the Iridium satellite data modem, that can be transported by a single person and powered by a vehicle’s battery. The system collects and processes data from RFID tags on equipment pallets and containers, then transmits it along with GPS position information through the Iridium satellite network to the DoD In-Transit Visibility network server.
Marines with the 2nd Force Service Support Group implemented the Iridium satellite-enabled equipment identification and tracking system. “The ultimate goal of this technology is to ensure front-line commanders know the exact location of equipment and supplies anywhere in the supply chain, as well as to decrease delivery times to the battlefield,” said Scheimreif.
Iridium is also in the process of upgrading its constellation of satellites. In a recent request for information, Iridium noted that it is looking for partners that will enable it to provide high-bandwidth data transmission, enhanced voice, short messaging services and innovative spacebased applications.
Enhancements are also being made to tactical satellite ground terminals. “Lighter, more expeditionary and higher capacity: those things [are] our driving principles,” said Marvin Shoemake, vice president for business development at General Dynamics SATCOM Technologies. “We are designing terminals with lighter weight materials, that operate at higher frequencies, and that have the capability of tracking the satellite as the vehicle is moving. Weight and size are big issues because the military would like to have the satellite terminals built right into the top or side of vehicles. That is not possible today.”
Enhancements to antennas as well as to the vehicles themselves are also important to enable satellite communications on the move. “Tracking stationary or LEO satellites on moving groundbased vehicles requires a very dynamic antenna plat-form,” Shoemake explained. Zero backlash motors and a tight steering mechanism are also required for the vehicle-mounted ground terminals to keep locked on a satellite.
RESPONSIVE SPACE
The conflicts in Iraq and Afghanistan have galvanized the military’s current emphasis on developing tactical satellite capabilities, and quickly. An interesting side effect of this effort has been to demonstrate that industry can deliver capabilities that meet requirements, at cost and on time.
“The point of responsive space is to bring down launch vehicle and payload costs and to being newer technologies to users quicker,” noted Raytheon’s Chrien. “We have seen development cycles of 12 to 18 months, instead of four to five years.”
Raytheon delivered TacSat-3, for example, in less than 15 months and for under $15 million. “We were used to long-term satellite programs and we had to rethink how we did business,” Chrien said.
The company was constrained by government requirements, he continued. “They wanted 80 percent of their usual performance at 20 percent of the cost. The government laid out its requirements and goals and didn’t change them the whole time. An unchanging set of requirements and a tight budget allow for clarity when it comes to thinking about making tradeoffs and coming up with solutions.” ♦
