Integration

Most people are familiar with the concept of RADAR. Radio frequency (RF) waves travel through the atmosphere, reflect off of a target, and return to the RADAR system to be processed. The amount of time it takes to return correlates to the object’s distance. In recent decades, this technology has been revolutionized by electronically scanned (phased) arrays (ESAs), which transmit the RF waves in a particular direction without mechanical movement. Each emitter varies its phase and amplitude to form a RADAR beam in a particular direction through constructive and destructive interference with other emitters.

The increased density of electronic components and subsystems in military electronic systems exacerbates the thermal management challenges facing engineers. The military platforms that host these systems often cannot physically accommodate the large cooling systems needed for thermal management, meaning that heat can be a limiting factor for performance of electronics and embedded computers.

The U.S. Military relies on the space-based Global Positioning System (GPS) to aid air, land and sea navigation. Like the GPS units in many automobiles today, a simple receiver and some processing power is all that is needed for accurate navigation. But, what if the GPS satellites suddenly became unavailable due to malfunction, enemy action or simple interference, such as driving into a tunnel? Unavailability of GPS would be inconvenient for drivers on the road, but could be disastrous for military missions. DARPA is working to protect against such a scenario, and an emerging solution is much smaller than the navigation instruments in today’s defense systems.

Success on the battlefield requires warfighters to know as much as possible about themselves, their surrounding environment and the potential threats around them. Dismounted infantry squads in particular risk surprise and loss of tactical advantage over opponents when information is lacking. While squads use many different technologies to gather and share information, the current piecemeal approach doesn’t provide the integrated, real-time situational awareness needed for individual warfighters and squad leaders to anticipate situations and effectively maneuver to positions of advantage. Providing this capability would provide dismounted squads with overwhelming tactical superiority over potential adversaries similar to what warfighters enjoy at the aircraft, ship and vehicle levels.

Microelectromechanical systems, known as MEMS, are ubiquitous in modern military systems such as gyroscopes for navigation, tiny microphones for lightweight radios, and medical biosensors for assessing the wounded. Such applications benefit from the portability, low power, and low cost of MEMS devices. Although the use of MEMS sensors is now commonplace, they still operate many orders of magnitude below their theoretical performance limits. This is due to two obstacles: thermal fluctuations and random quantum fluctuations, a barrier known as the standard quantum limit.