How tiny waves of matter may help missiles stay on track

SCIENTIFIC AMERICAN MAGAZINE: Getting GPS Out of a Jam
How tiny waves of matter may help missiles stay on track

http://www.scientificamerican.com/article.cfm?id=getting-gps-out-of-a-jam&sc=DD_20101015

"To get around this potential risk, U.S. scientists are developing
gadgets that can track an object’s position in the event GPS signals are
cut off. These inertial measurement units, or IMUs, determine a target’s
location by measuring changes in acceleration since the last GPS
reading. Until now such devices, based on a variety of technologies from
mechanical to laser-based, have often been bulky and prone to error
after prolonged use. By taking advantage of the quantum-mechanical
properties of matter, however, engineers have come up with gadgets that
could prove 1,000 times more accurate".

The Scientific American story is likely based on last month's live
blog with Dahm:

http://www.defense.gov/Blog_files/Blog_assets/20100913_dahm_transcript.pdf

"The real big breakthroughs, I think, are going to come from these
quantum interferometry approaches which can be used -- they're often
referred to as cold-atom approaches, or Bose-Einstein condensate
approaches, where we trap a collection of atoms or molecules in a
very, very narrow range of quantum states. And we use the fact that at
the quantum level matter -- in other words, atoms and molecules -- are
waves.

And we can do interferometry with those matter waves in the same way
that we do with optical waves in ring laser gyros, for example. But
the wavelength of these matter waves is many, many orders of magnitude
smaller than optical wavelengths. And as a consequence, we get
incredibly high precision, low drift, in our position and navigation
that we can achieve with those kinds of systems.

Now, those systems are at laboratory scale today, but they are
advancing very, very quickly. And we have efforts under way to
continue to advance the technologies, as well as early efforts to
miniaturize those technologies and begin to get them down to the chip
scale where they will, perhaps a decade or more from now, begin to be
ready to insert into the systems that we field.

If we can successfully do that, then we will be able to have GPS- or
better-than-GPS-like position and timing information, even in GPS-
denied environments. And by doing that, we will, in effect, have
negated our potential adversaries' value from their efforts to deny us
GPS in the first place. So this is absolutely critical to everything
the Air Force and DOD does. And it's for that reason that it -- that
it's called out in Technology Horizons."


The releasable "Technology Horizons" report is here:

http://www.af.mil/shared/media/document/AFD-100727-053.pdf

The one specific program referenced in the report is managed by
DARPA's Defense Sciences Office (DSO):

http://www.darpa.mil/dso/thrusts/physci/newphys/pins/

"The Precision Inertial Navigation Systems (PINS) program seeks to use
ultra-cold atom interferometers as an alternative to GPS position
updates. Advancements in atomic physics over the past two decades have
allowed scientists exquisite control over the external quantum states
of atoms, including the deliberate production of matter waves from
ultra-cold atoms. This has allowed the development of matter wave
interferometry techniques to measure forces acting on matter=97including
high-precision atomic accelerometers and gyroscopes. An inertial
navigation system that used this technology would have unprecedented
drift rates; however, many scientific and technical challenges remain.
The PINS program will demonstrate a high-precision atom interferometer
inertial navigation system on an aircraft by the year 2013, with a
total system volume under 20 liters. As this is an entirely inertial
system, it will require no transmissions to or by the platform=97a jam-
proof, non-emanating inertial navigation system with near-GPS
accuracies for future military submarines, aircraft, and missiles."

A 20 liter volume corresponds to a cube with edges about 10.7 inches.
A cubic foot is about 28 liters.

DARPA/DSO issued a contract a year ago to AOSENSE in Sunnyvale CA.

http://www.defense.gov/contracts/contract.aspx?contractid=3D4117

"AOSENSE, Inc., Sunnyvale, Calif., was awarded on Sept. 3, 2009, a
$11,230,139 cost-plus-fixed-fee contract. This contract is for the
High Dynamic Range Atomic Sensors (HiDRA) effort will build on the
Precision Inertial Navigation System (PINS) work by demonstrating that
atom optic (AO) sensors can outperform existing technologies in the
presence of realistic platforms dynamics for a broad range of military
applications. The goal of this program is to provide jam-proof, non-
emanating inertial navigation with near-GPS accuracies for future
military systems. Work is to be performed in Sunnyvale, Calif., with
an estimated completion date of Sept. 13, 2011. Bids were solicited
on the World Wide Web with more than 25 bids received. Defense
Advanced Research Projects Agency, Arlington, Va., is the contracting
activity (HR0011-09-C-0116)."

AOSENSE has a web site that posts very little information:

http://www.aosense.com/

The listed contact, Brent Young, was (or maybe still is) a physics
professor at Stanford, working on gravity gradiometry in Mark
Kasevich's group:

http://atom.stanford.edu/

http://atom.stanford.edu/Publications.html

DARPA program manager:

http://spectrum.ieee.org/aerospace/astrophysics/profile-out-of-sight