Going Forward - GPS Declassified: From Smart Bombs to Smartphones - page 194

satellite, orbiting at 390 miles above Earth, and the ground control system
together cost about $500 million. 76 Based on 2013 budget requests, the Air
Force may be moving toward acquiring a second sbss satellite. 77
Observers have asked whether the U.S. military is too dependent on space,
but when it comes to both military and civilian use of gps, a common refrain
is, “There is no going back.” 78 That shared dependency comes with an enor-
mous and growing financial commitment. The United States will spend nearly
$10 billion for military space programs in fiscal year 2013 alone, but cost over-
runs can quickly eat up an entire year's worth of funding. In March 2012 gao
reported that spending on major defense satellite acquisition programs, of
which gps is but one, increased by about $11.6 billion—a 321 percent rise—
from original cost estimates for the ive-year fiscal period 2011 through 2016. 79
The first two gps iii satellites, at $1.6 billion and $1.4 billion respectively, did
not meet the original schedule and exceeded their estimated cost by 18 per-
cent. 80 As the United States grapples with long-term structural budget deficits,
military budgets will come under pressure, and that will almost certainly affect
the future of gps.
What's Next for GPS Users?
Current applications are the starting point in forecasting how we may use gps
in coming decades. Military dependence on gps may decrease as the Penta-
gon explores new techniques to replace, augment, or back up the signals. Often
mentioned is developing eLoran, a modernized version of the ground-based
long-range navigation system Loran C that the United States decommissioned
in 2010. The enhanced version requires fewer ground stations and broadcasts
high-powered, low frequency, unjammable signals for use on the earth's sur-
face and up to jet altitudes. 81 The Defense Advanced Research Projects Agency
(darpa), through its Micro-pnt Program, is working on self-calibrating iner-
tial navigation and guidance systems, which combine clocks, accelerometers,
gyroscopes, and calibration circuitry into an eight-millimeter cube. 82 Self-
contained inertial navigation units that do not require gps to correct drift would
be impervious to jamming or spoofing. A radio-navigation system that mimics
gps but works indoors and in underground mines, where gps signals do not
reach, has won Air Force backing. The Air Force signed a contract in 2010 with
Locata, a privately owned Australian company, to provide a non-gps compo-
nent for its next-generation Ultra High Accuracy Reference System, an amal-
gamation of gps and other pnt techniques aimed at overcoming jamming. 83