ARLINGTON, Va., 29 Sept. 2013. U.S. military researchers have chosen two companies to develop technology for radio frequency spectrum sharing among radar and communications systems with the goal of improving overall radar and communications capability.
Officials of the U.S. Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., have awarded contracts to the Lockheed Martin Corp. Advanced Technology Laboratories in Cherry Hill, N.J., and Science Applications International Corp. (SAIC) in McLean, Va., for the Shared Spectrum Access for Radar and Communications (SSPARC) program.
The SSPARC program, sponsored by the DARPA Strategic Technology Office, seeks to develop technology applicable to spectrum sharing among military radar and military communication systems, as well as among military radars and commercial communications systems.
Program work will include spectrum sharing systems and separation mechanisms, supporting technologies that improve performance when sharing spectrum, theoretical performance limits and grounded design techniques, and relevant regulatory topics, DARPA officials say.
DARPA awarded a $2.6 million contract to Lockheed Martin earlier this month, as well as a $2.1 million contract to SAIC for the SSPARC program.
Spectrum congestion is a growing problem, DARPA experts say. It increasingly limits operational capabilities due to the increasing deployment and bandwidth of wireless communications, the use of network-centric and unmanned systems, and the need for increased flexibility in radar and communications spectrum to improve performance and to overcome sophisticated countermeasures.
Radar and communications together consume most of the highly desirable spectrum below 6 GHz, and the SSPARC program will try to develop sharing technology that enables sufficient spectrum access within this desirable range for radar and communications systems.
The SSPARC program seeks to support two types of spectrum sharing. First, it seeks to share spectrum among military radars and military communications systems and both capabilities simultaneously when operating in congested and contested spectral environments.
Second, the program seeks to share spectrum among military radars and commercial communications systems by preserving radar capability while meeting national and international needs for increased commercial communications without the high cost of relocating radars to new frequency bands.
In cooperative spectrum sharing, radar and communications systems share information in near real time, which enables the systems not to interfere with each other based on how they actually use the spectrum, not on how they might use it, DARPA researchers say.
Lockheed Martin RF experts will combine an extensible cognitive control plane with several system-level and device-level spectrum separation techniques, DARPA officials say.
Company experts will demonstrate scalability through separating global control from several local control systems, with the battlespace partitioned intelligently via RF propagation analysis and geospatial reasoning; develop and characterize spectrum-sharing techniques by capitalizing on closed-loop information sharing between the radar and communications systems; and manage the cognitive control system by a spectrum sharing priority dial, which battlefield commanders can use to rebalance resources as needed.
SAIC, meanwhile, will combine a distributed spectrum resource manager by employing a machine learning control layer with three spectrum sharing techniques chosen to support the transition.
SAIC engineers will develop a strong code-in-the-loop simulation approach by capitalizing on validated models of radar and military radio transition targets, DARPA officials say.