http://www.sciencecodex.com/nasa_engineers_tapped_to_build_first_integratedphotonics_modem-174483

http://www.sciencecodex.com/nasa_engineers_tapped_to_build_first_integratedphotonics_modem-174483

Data Rates Demand New Technology

Since its inception in 1958, NASA has relied exclusively on radio frequency (RF)-based communications. Today, with missions demanding higher data rates than ever before, the need for LCRD has become more critical, said Don Cornwell, director of NASA’s Advanced Communication and Navigation Division within the space Communications and Navigation Program, which is funding the modem’s development.

LCRD promises to transform the way NASA sends and receives data, video and other information. It will use lasers to encode and transmit data at rates 10 to 100 times faster than today’s communications equipment, requiring significantly less mass and power. Such a leap in technology could deliver video and high-resolution measurements from spacecraft over planets across the solar system — permitting researchers to make detailed studies of conditions on other worlds, much as scientists today track hurricanes and other climate and environmental changes here on Earth.

The project, which is expected to begin operations in 2019, isn’t NASA’s first foray into laser communications. A payload aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) demonstrated record-breaking download and upload speeds to and from lunar orbit at 622 megabits per second (Mbps) and 20 Mbps, respectively, in 2013.

LCRD, however, is designed to be an operational system after an initial two-year demonstration period. It involves a hosted payload and two specially equipped ground stations. The mission will dedicate the first two years to demonstrating a fully operational system, from geosynchronous orbit to ground stations. Once NASA demonstrates that capability, it plans to use ILLUMA to test communications between geosynchronous and low-Earth-orbit spacecraft, Cornwell said.

An Exceptional Terminal

ILLUMA incorporates an emerging technology — integrated photonics — that is expected to transform any technology that employs light. This includes everything from Internet communications over fiber optic cable to spectrometers, chemical detectors, and surveillance systems, to name just a few.

“Integrated photonics are like an integrated circuit, except they use light rather than electrons to perform a wide variety of optical functions,” Cornwell said. Recent developments in nanostructures, meta-materials, and silicon technologies have expanded the range of applications for these highly integrated optical chips. Furthermore, they could be lithographically printed in mass — just like electronic circuitry today — further driving down the costs of photonic devices.