Mercury system provides power for 1,000 STAP processors
By John McHale
BALTIMORE - Experts at Northrop Grumman Electronic Sensors and Systems Division in Baltimore needed a flexible, powerful computer system able to handle as many as 1,000 processors at once for the Space-Time Adaptive Processing (STAP) project as part of the Mountain Top surveillance program of the U.S. Navy and Defense Advanced Research Projects Agency.
The RACES Series MultiPort family from Mercury Computer Systems Inc. in Chelmsford, Mass., gave them the performance they needed. Scientists at MIT Lincoln Laboratories in Lexington, Mass., will use the system to develop progressive methods for the analysis of complex STAP algorithms.
Supporting more than 1,000 SHARC or PowerPC processors in one logical system and using the RACEway Interlink switched fabric interconnect, the MultiPort family provides more than 12 million floating point operations per second in each cubic foot of processing power for embedded applications.
"The Northrop Grumman solution with Mercury`s scalable, heterogeneous architecture was selected following an intense competitive evaluation," says Harold Ball, program manager for the Programmable Signal Processor Program at Northrop Grumman. "After detailed architectural analysis, the MIT Lincoln Labs developers chose a system with proven scaleability, and demonstrated success in high-performance, deployable applications for the military."
The aggregate bandwidth of as much as 6.4 gigabytes per second comes from by Mercury`s quad-port technology, which provides four individual RACEway channels on one 9U VME board.
The pizza box-size 9U is it is the only way to achieve the power necessary for STAP applications, explains Steve Patterson, director of product marketing at Mercury. Putting this type of power on a 9U board is the first step towards putting it on a smaller, more embeddable 6U board, he says.
The key challenge to this board was routing all crosspoint switches, chips, and ports to make them scaleable in an active backplane, says Barry Isenstein, vice president and director of strategic marketing at Mercury. Although the computing technology was already available on a 6U with less power, the larger 9U board, while not as rugged as a 6U, is still rugged enough for harsh environments. The key for achieving the high power was integration of existing components on a larger scale, Isenstein says.
Mercury`s heterogeneous STAP system, based on the standard RACEway Interlink, comprises 948 Analog Devices SHARC digital signal processors and 24 Apple/ IBM/Motorola PowerPC processors. It has a peak performance of 118 billion floating point operations per second and supports memory up to 20 gigabytes.
Scientists performed the Initial development work on a smaller 144-processor (126 SHARC and 18 PowerPCs), 2-gigabyte system with a peak performance of 17 billion floating point operations per second.
Supporting the MultiPort systems are Mercury`s MC/OS runtime environment, providing interfaces for the various processing components.
Most radar systems have difficulty detecting small targets in the presence of clutter and jamming. Using STAP, which provides advanced signal processing, the scientists expect to identify moving objects despite interference from other signals. By adaptively emphasizing the desired signal and blocking out the extraneous signals, the STAP system is expected to yield higher image definition than current systems allow.
In contrast to conventional two-dimensional radar processing, STAP processing is inherently three-dimensional (i.e. range /pulse /antenna-element). Real-time processing requirements for STAP typically range from 20 -100 billion floating point operations per second.
RACES Series MultiPort family from Mercury Computer Systems, Inc., in Chelmsford, Mass. can handle up to 1,000 processors at once for the Space-Time Adaptive Processing as part of the DARPA/Navy Mountain Top Program.
