Future satellite communications will bear no resemblance to Star Wars
April 6, 2011
Researchers are redefining the costs and performance of Soldier satellite communications on-the-move to address current and future challenges.
The Research, Development and Engineering Command's communications-electronics center, or CERDEC, in collaboration with Program Executive Office, Command, Control and Communications Tactical, or PEO C3T, is looking to replace the L-Band SOTM terminals supporting Force XXI Battle Command Brigade and Below, or FBCB2, with X-Band terminals.
This effort is being done through the transition of PEO C3T's Army Small Business Innovation Research project, Small Aperture X-band Antenna, or SAXBA, to the Army Technology Objective, Affordable Low Profile Satellite, or ALPS, program. The ATO program aims eliminate the need to use the expensive, commercially-leased L-Band satellites by further developing a SOTM terminal that is able to utilize the X band portion of the DoD-owned Wideband Global System.
FBCB2, a battle command information system in military vehicles, utilizes the L-Band SOTM terminals to provide situational awareness from brigade to vehicle level forces, said Joe Shields, a branch chief of CERDEC's Space and Terrestrial Communications Directorate's SATCOM Systems Division.
The costs associated with leasing the commercially-available L-Band satellite bandwidth are estimated to be $40 million a year, said Tat Fung, technical lead for the project. "The benefit is really its reduced life cycle costs, which is the annual satellite leasing cost of the L-Band," said Fung.
In addition to the cost concern associated with the L-Band, other issues like security and accessibility are what prompted Shields and a team of experts to research alternative options. Because commercial satellites have fewer restrictions on who can utilize them, the military has to compete with commercial users which has, at times, resulted in lowered bandwidth availability for troops overseas, he said.
"For the Soldiers in Afghanistan, L-Band access is a challenge, and right now there are X-Band satellites right over theater," Shields said.
Because of its government-only availability, utilizing X-Band, one of the WGS bands, can potentially enable better access to communications.
"You've got thousands of units out in the field; whoever wants to transmit has to lease the bandwidth. L-Band right now comes only from commercial sources. WGS is government only, you don't have to pay for the bandwidth, you just have to go through the process to be approved and validated for use," Shields said.
While cutting costs is one aim of the SAXBA project also aims to add functionality by utilizing high performance phased array antennas, transceiver and antenna pointing technologies that can be electronically steered rather than mechanically to track a communication satellite while on the move. The technologies are scalable to provide low-profile distributed antenna systems for various land, air, and water platforms with different data throughput requirements.
The low-profile phased array antennas will also help to ensure safer operation for deployed Soldiers on platforms with SATCOM on-the-move communications.
"If you have seen some of these mechanical tracking on-the-move dish antennas that look like Star Wars' R2D2, they can be a bullet magnet. They are highly visible. SAXBA shows that we are making antennas much smaller - they are harder to see in addition to being cheaper to use and having a lower vertical height," Shields said.
"When you are in a bouncing humvee [Highly Mobile Multi-purpose Wheeled Vehicle or HMMWV], you don't have to worry about making an antenna dish point at a fixed spot in the sky far away, because doing everything electronically is almost instantaneous and much more agile. The Soldiers out there in the field probably want something they slap on the top of the vehicle, turn it on and ignore it, which is one of the things we are trying to do."
To further prove-out their work, Shields and his team are conducting on-the-move antenna testing in May. In the summer, they will test the fully integrated SAXBA BFT terminals, from Alico Systems Inc., in field-like environments, incorporating the technology onto military vehicles. Shields hopes to demonstrate the terminal's capabilities as a potential replacement for L-Band use.
"We are bringing solutions into a military SATCOM environment." Shields said. "There's going to be a need for all these sorts of SATCOM antennas and we are just filling another niche now."