Scientists and engineers are adopting GPS for a variety of environmental uses, including monitoring bridges, earthquake fault lines, bird migration patterns, and endangered species. Researchers in the United Kingdom demonstrated in 2006 that GPS sensors could detect bridge movements of less than a centimeter. By establishing a baseline for bridge deflections due to traffic loads, temperature, winds, and deterioration, GPS sensors can alert authorities when bridge movements exceed design tolerances.155 Russian engineers in 2011 installed sensors with dual GLONASS/GPS receivers on a new 3,887-foot cable suspension bridge—the world’s longest—linking the far eastern city of Vladivostok to Russky Island.156 Such dual-signal receivers roughly double the number of potential satellites visible, making them ideal for locations where tall buildings, tree canopies, or bridge structures mask parts of the sky.
Like surveyors, geophysicists did not need the full complement of satellites to begin monitoring fault lines using GPS receivers bolted to solid rock at surveyed positions in earthquake-prone areas. China installed its first GPS earthquake monitors in 1985.157 The Southern California Earthquake Center had installed 350 monitors in the region by 1991.158 A year after the January 17, 1995, earthquake in Kobe, Japan, that killed more than six thousand people, the government doubled the number of GPS monitoring sites across the island nation to about one thousand.159 GPS sensor measurements before and after the magnitude 8.8 earthquake that struck southern Chile on February 27, 2010, showed that it moved the entire city of Concepción about ten feet west and shifted Buenos Aires, Argentina—eight hundred miles from the epicenter—about an inch.160 Seismologists announced plans to add fifty sensors to the twenty-five already in the region.161 The March 11, 2011, magnitude 9.0 earthquake off the coast of Japan that caused devastating tsunami waves intensified the search for faster analysis and earlier warnings. Initial reports underestimated the magnitude as 7.1 because severe shaking often saturates seismometers near large quakes. By the time geophysicists calculated the actual intensity more than twenty minutes later, authorities had lost valuable time needed to alert people ahead of the waves.162 NASA announced in April 2012 its collaboration with several universities and scientific organizations to test a new warning system, the Real-Time Earthquake Analysis for Disaster (READI) Mitigation Network.163 It uses satellites to monitor about five hundred GPS ground sensors across California, Oregon, and Washington.164 Scientists involved in the project say the system could have established the magnitude of the 2011 Japan earthquake within two to three minutes.165
Along with precise positioning and navigation, the atomic clock accuracy of GPS time has become an unseen but ubiquitous background utility. More than five hundred thousand timing GPS receivers support industry around the world.166 They help millions of individuals and businesses to simultaneously download and upload data across private networks and the Internet. Packets of digitized information speed through electronic networks like vehicles on crowded freeways, and precise time synchronization is a prerequisite to maintain smooth flow. Consider the importance of precise time stamping on large electronic financial transactions when market prices are fluctuating rapidly. A clock error of ten parts per million will grow to almost a full second in one day.167 Network technicians install time synchronizing equipment like Spectracom’s SecureSync system or Symmetricom’s SyncServer SGC-1500 Smart Grid Clock, which keeps an electric utility’s substation clocks synced to GPS time within one microsecond.168 Precise time synchronization helps power companies manage transmission networks, isolate faults, and balance loads. It is a key element in making our electric grids “smarter ” and more secure as utilities begin to integrate dispersed renewable power sources, such as wind turbines and solar cells, with traditional sources, such as centralized coal, gas, and nuclear plants. In the telecommunications industry, most of the world’s half-million cellular base stations utilize GPS timing equipment to switch calls (usually seamlessly) from one tower to the next as mobile phone users drive along roadways.169
GPS technology is seeping into other commercial and professional activities as users find ways to improve accuracy, increase productivity, lower costs, save time, or enhance safety. While commercial users account for a quarter of GPS equipment sales—less than half the consumer market—the $8.3 billion they spend and the uses they make of GPS yield a large economic impact. Estimates of the aggregate economic benefits to all commercial GPS users in the U.S. economy range from $68 billion to $122 billion annually, representing between 0.5 and 0.9 percent of gross domestic product.170
Delays and Distortions
Consumers, commercial users, and the military have shared a desire for greater precision and helped to drive improvements in GPS technology. From the golfer using a range finder to estimate the distance to a green, to the city worker mapping fire hydrant coordinates in snow-heavy locales, to search-and-rescue crews locating a downed pilot, accuracy is key. One reason the Air Force felt compelled to comment publicly in late 2009 on reports about drivers getting lost using GPS was as part of its ongoing pushback against widespread perceptions that aging satellites were making the system inaccurate. This public relations problem began in May 2009, when the Government Accountability Office briefed the House Subcommittee on National Security and Foreign Affairs about problems in the GPS IIF satellite replenishment program. The IIF generation consists of twelve Boeing-built satellites designed to replace a group of the original operational satellites, some launched between 1990 and 1993 and now far beyond their expected seven-and-a-half-year life spans. The GAO warned that cost overruns and production delays threatened the Defense Department’s ability to replace the aging satellites quickly enough to maintain its performance guarantee of twenty-four operational satellites 95 percent of the time. The IIF program was then $870 million over its original $729 million cost estimate, and the first launch, scheduled for November 2009, was about three years late.171 While commending the Air Force for taking steps to avoid similar problems in the forthcoming GPS III satellite program (which included switching the prime contractor from Boeing to Lockheed Martin), GAO said there was a “high risk ” that the GPS constellation would fall below twenty-four satellites between 2010 and 2014.172
The hearing itself drew scant media coverage. Major news outlets seemed more focused on the Obama administration’s proposal to defund Loran C, a long-range, ground-based radio navigation system that some thought GPS had rendered obsolete.173 Government Computer News posted one of the few stories to appear the next day under the headline “DOD Faces Tough Hurdles in Maintaining, Upgrading an Aging GPS. ”174 As the story spread to other media, online and overseas, the headlines grew more dramatic. The science and technology website Gizmodo.com announced, “GPS Accuracy Might Be Less Accurate in 2010 ,” while Engadget.com offered, “GPS System Might Begin to Fail in 2010, Government Accounting Office Warns. ”175 The UK-based Guardian Unlimited upped the ante with “GPS System ‘Close to Breakdown ,” ” and the newspaper mX, in Melbourne, Australia, served up “Satnav Crisis: So Where the Hell Are We? ”176 RusData DiaLine, a unit of Russia’s Izvestia, penned the optimistic headline “Russia’s GLONASS to Profit from GPS Problems. ”177 Such headlines called to mind the breathless reporting of the Vanguard-Sputnik era and the atmospherics that often accompany stories about technology managed by the military.
The Air Force countered with a public relations offensive, including news releases, interviews, the Air Force Space Command’s first use of Twitter for a two-way “tweet forum ,” and an informational video on YouTube.178 Col. Dave Buckman, chief of Space Command’s Positioning, Navigation and Timing Division, tweeted, “GPS will not go down. ”179 In the video Lt. Gen. John E. Hyten, vice commander of Air Force Space Command, explained that thirty-four satellites were in orbit, two launches were scheduled in the coming year, and in the worst year of GPS’s history (2000) no more than three older satellites stopped working, providing an ample cushion above the twenty-four-satellite threshold. “It’s the healthiest co
nstellation that we’ve ever had ,” Hyten noted, “and we are very confident that we’ll be able to maintain that level of performance in GPS now and well into the next decade. ”180
Critics noted that despite the large number of orbiting satellites, each with built-in redundancies such as multiple atomic clocks, many older ones were down to “single thread ” operation, meaning one more component failure could leave a satellite unusable.181 Widely reported signal problems with a satellite launched in March, just two months before the GAO uproar, made the Air Force’s public relations task more difficult. The satellite, SVN 49, was the last of eight IIR(M) models, which introduced a second civilian signal (L2C). Engineers added equipment to SVN 49 to demonstrate and test the new L5 signal intended for commercial aviation use that would be a standard feature of the IIF series. That change inadvertently affected the other signals, causing a permanent multipath (reflected) signal—a thirty-nanosecond echo—within the satellite itself.182 The effects of the signal distortion varied with the angle of the satellite in the sky and the type of receiver, complicating potential remedies for the problem.183 At this writing SVN 49 remains listed as “unusable. ”184
Such problems tended to attract more publicity than a significant advance that occurred about the same time. The Naval Research Laboratory and a team comprising mobile satellite service provider Iridium Satellite, Boeing, Rockwell Collins, Coherent Navigation, and academic experts in 2009 demonstrated the feasibility of the High Integrity GPS program, an augmentation system sometimes called iGPS or HIGPS. The program uses Iridium’s constellation of sixty-six low-earth-orbiting satellites to broadcast powerful signals with embedded GPS data, allowing military receivers to lock onto GPS signals faster and maintain them under substantial enemy jamming while in a moving vehicle.185 Boeing completed the first phase of implementation in 2011, modifying the computers and software that control Iridium satellites, and is now working on the NRL’s HIGPS operations center, reference stations, and user equipment.186
The Air Force finally launched the first IIF satellite, SVN 62, in May 2010. GPS officials acknowledged in September that during the standard three-month test period they had discovered a software problem in the cross-links that allow satellites to communicate with each other.187 The problem degraded the system that detects nuclear detonations but did not affect the satellite’s navigation and timing signals, so it joined the operational fleet. However, the issue postponed the second IIF launch until 2011, when the software fix would be transmitted to the orbiting satellite.188 The cross-link software glitch came on the heels of news that surfaced in June about another IIF-related software problem that January. Compatibility issues left as many as ten thousand military receivers useless for several days after crews installed new ground control software for the IIFs.189 The Air Force delayed the June launch of the second IIF satellite for two weeks and shut off the orbiting satellite’s military signal while fixing another issue, described first as an anomaly and later as an electrical problem.190 Depending on their point of view, observers have blamed the IIF program’s troubles and bad publicity on complacency, poor oversight, inherent design flaws, overly ambitious production plans, the challenges of increasingly complex technology, heightened media scrutiny, and gremlins. After all, how many people have set up a new computer without any glitches? But the $121 million spent on average per satellite makes public interest and concern understandable.
Although fears of a complete GPS failure receded, the GAO warning focused broader attention on brownouts.191 These are temporary periods of an hour or two, widely scattered geographically and throughout the year, when too few satellites are visible for high-precision users such as farmers and heavy equipment operators. Having thirty satellites in the constellation for several years had reduced this inconvenience. If the constellation drops to twenty-four or fewer satellites, users would more often notice a difference, particularly when trees or buildings block one or two satellites. Many high-end GPS receivers have dual-frequency capability, like the bridge sensors mentioned earlier, to take advantage of any additional Russian GLONASS satellites in view. The brownout issue illustrates how users benefit from other satellite navigation systems now joining GPS in orbit. However, other GPS-like systems—often referenced generically as GNSS, for any global navigation satellite system—spark competition and occasional conflict.
Everybody Wants One
As mentioned in the preceding chapter, GLONASS began in 1982 under the Soviet regime and attained twenty-four operational satellites in 1995. It declined precipitously in the latter half of the 1990s because each satellite had only a three-year design life.192 GLONASS uses a different type of radio signal but otherwise is very similar to GPS. Some have asserted that the Bank of Credit and Commerce International (BCCI), which collapsed in 1991 amid a scandal involving financial fraud, money laundering, illicit technology transfers, arms sales, and drug trafficking, sold Soviet spies secret NAVSTAR GPS plans.193 A source in the investigation showed Time magazine reporters various photographs he claimed to have made of NAVSTAR technical documents in the Kremlin, but it is unclear when or how the Soviets acquired them.194 While the U.S. military’s signal encryption codes are top secret, some aspects of GPS have been public and published for commercial users from the start. Russian Federation president Boris Yeltsin opened GLONASS for civilian use in 1999, but the Moscow Times described the fleet as being “in a dismal state ”—nine satellites in orbit and only six working—when the Russian Cabinet in August 2001 approved spending 23.6 billion rubles (roughly $800 million at the time) to rejuvenate the constellation over ten years.195 The second-generation satellite, designated GLONASS M, added another civilian frequency, improved the antennas, and more than doubled the life span, to seven years.196 Russia in 2007 announced GLONASS K, a smaller, lighter version with a third civilian signal and twelve-year design life, offering the option to launch as many as six on a single rocket.197 In December 2011 the GLONASS constellation again reached twenty-four operational satellites, and at a March 2012 navigation conference in Munich, Germany, a Russian Space Agency official confirmed his nation’s desire to expand the constellation to thirty.198 The Russian government has approved 347 billion rubles (nearly $12 billion) through 2020 for new satellites, a ground-based differential augmentation system, and a new operational control system.199 A 2006 agreement gave India access to GLONASS military signals and gave the Russian program a cash infusion.200 Russia offered India full joint partner status in mid-2012.201 Russian efforts at international cooperation have included making GLONASS signals compatible with GPS signals and committing to have every GLONASS satellite by 2020 broadcast code division multiple access (CDMA) signals, the format GPS and other systems use (see chapter 5), along with its native format, frequency division code modulation (FDMA). However, Russia sometimes plays hardball. In a move presumably backed by President Vladimir Putin, Moscow threatened in mid-2012 to block imports of mobile phones and other devices that do not have dual GPS/GLONASS chipsets.202
The European Union’s Galileo system is about five years behind schedule. Proposals for a civilian-run European alternative to GPS predate by a decade the 1993 Maastricht Treaty establishing the EU. The European Space Agency (ESA), with eleven members in 1983, proposed a constellation of twenty-four satellites at a time when budget woes had U.S. officials scaling GPS back to eighteen.203 ESA officials thought they could build their system for about $2.5 billion, half the GPS estimate, and begin launching satellites in 1988, the year U.S. officials anticipated completing GPS.204 By the early 1990s European plans envisioned a public-private partnership building a thirty-satellite constellation offering a mix of free basic service and fee-based precision landing guidance.205 After EU leaders in Brussels, Belgium, approved the first funds in 1999 for a $3.06 billion program cosponsored with ESA, it took five years to reach an agreement with U.S. military officials, who were concerned about Galileo’s signals interfering with GPS military signals.206 China invested €200 millio
n (about $270 million) in Galileo in 2003 but complained that it felt shut out of decision making after private sector funding collapsed. The EU rescued the program with public funds, which tended to elevate political and security concerns.207
China launched its first Beidou (sometimes called Compass) satellite in 2007, apparently seeking to leverage negotiations with the EU, but talks failed.208 In April 2009 China launched its second Beidou satellite, effectively ending its relationship with the EU, and announced that the Beidou system would use some radio frequencies Galileo had reserved for encrypted governmental, public safety, and possible military use.209 It was an aggressive but legal move. The United Nations International Telecommunications Union, which allocates radio spectrum for satellites, grants priority to the first country establishing services at a specific frequency.210 It is unclear whether the EU could have salvaged the partnership. Later that year a retired People’s Liberation Army colonel told a reporter that since the 1996 missile crisis in the Taiwan Strait, China had been committed to building its own GNSS. During the standoff the Chinese army fired three GPS-guided missiles toward Taiwan as a warning against seeking independence, and the second two missiles went awry. Military officials suspected someone disrupted the GPS signals, and the retired colonel called the incident an “unforgettable humiliation. ”211
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