GREG RIKER GETS AROUND. And during the course of his travels, he knows precisely where he is, where he's been, and where he's headed at any given moment.
Riker’s high-tech land yacht is equipped with several laptops, a Motorola Envoy, a SkyTel 2-Way pager, and two cellular phones. But his ability to pinpoint his exact location and destination is a function of the Trimble Mobile Global Positioning System (GPS) PC Card attached to his dashboard-mounted Toshiba T-2000 pen-based computer.
As Riker rolls down the road, an antenna on the roof of his motor home picks up satellite signals that are carried to a GPS receiver wired to the PC Card. The card converts the signals into data delineating the vehicle’s location, speed, and direction of travel. The card then feeds that information into Automap Pro, a digital mapping program from Microsoft. A map appears on the Toshiba’s display, and a representation of the motor home moves along that map.
Riker also takes advantage of a variety of databases that work in conjunction with GPS. A directory of National Public Radio stations, for instance, enables him to locate the nearest one on his map. He then clicks on the corresponding antenna icon, and the program displays that station’s call letters and frequency.
GPS is becoming increasingly popular with road warriors who feel the need for a navigator at their fingertips. And in conjunction with all the applications that run through it, the system “completely changes the activity of driving,” Riker says.
The Genesis of GPS
GPS is the result of a $12 billion project launched by the U.S. government in the 1970s for military use. The system went into full operation in 1993, when the last of 24 radio-equipped satellites went into orbit. Each satellite sends a constant stream of information from 12,000 miles above the earth to land-based receivers that then can calculate their own location with astounding precision.
Using the combined data transmitted from three satellites, a GPS receiver can pinpoint its two-dimensional position. With information from a fourth, it also can reckon its altitude. If those coordinates are continually updated and displayed on a grid, the technology can be used for a surprising number of purposes.
GPS originally was developed to enable the military to pinpoint battlefield targets and position troops, and it proved to be extremely effective. So effective, in fact, that the Pentagon decided that it would be unwise to make the system universally accessible. It therefore added a security feature known as “selective availability” that scrambled the signals.
Each satellite sends two sets of signals. One, with accurate data, is encoded for the military, and requires properly equipped receivers to unscramble it. The general public tunes into data that is modified just enough to be impractical for precise combat applications. Military signals are accurate within a 20-meter radius, while the public system generates readings that can be up to 100 meters off target.
However, in March, as a way to maintain the GPS network and to encourage the development of a commercial market for the technology, the Pentagon announced that they will phase out selective availability over the next four to ten years, at which point everybody will share that within-20-meter accuracy. This will be important as more critical civilian uses – such as GPS for ambulance drivers and aircraft – are found. Experts also say that technological advances over the past few years has made selective availability less effective from a security standpoint.
The GPS Market
GPS is most commonly used for navigation in moving vehicles and emergency rescue operations using links to cellular phones. According to the United States G.P.S. Industry Council, an association of manufacturers of GPS receiver equipment, by the year 2000 sales of GPS-based automobile navigation products such as receivers will top $3 billion, up from $100 million in 1993. Similarly, annual sales of GPS systems that combine receivers and cellular applications are
expected to soar to $2.3 billion by 2000, up from $45 million in 1993.
The primary force behind this growth is the continuing drop in the cost of GPS hardware. The price of receivers, for instance, has been falling 30 percent per year for the last few years. And as the performance of microprocessors improves, less hardware is needed to manufacture GPS equipment.
Rockwell International, which built the first of the GPS satellites, sells an integrated three-chip set to manufacturers for $70. Philips, SGS-Thomson, Motorola, and other firms plan to offer chipsets of their own for less than that amount. This translates into off-the-shelf prices of less than $600 for a PC-based GPS PC Card or hardware. Moreover, these GPS products are expected to continue to drop to approximately $100.
The decline in the price of computers is also spurring growth in the GPS market. Type II PC Card slots are now standard features in notebook computers, which also offer the graphical environment that mapping software requires. Although retailers now sell a wide variety of GPS PC Card receivers, most of the hardware comes from Trimble Navigation Ltd. and Rockwell Semiconductor Systems as part of an OEM deal that enables other companies to add software and package the products under their own brand.
While GPS was born in the United States, Japan is currently the world’s biggest market for car navigation systems. In a country of 60 million vehicles, 350,000 GPS devices were sold in 1994, while that number climbed to 500,000 last year.
In addition, according to a recent study by the Arlington VA-based Consumer Electronics Manufacturers Association, more than half of consumers surveyed know about car navigation systems and almost one-fifth would like to have some type of navigation assistance.
However, unlike the US, car navigation GPS units are more widely used in Japan, where there now are more than 500,000 sensor-equipped cars.
As the market for GPS receivers takes off, so do sales of geographical information systems (GIS) software. In the already competitive arena of mapping software, a number of firms are racing to develop products that take advantage of GPS. DeLorme’s MapExpert covers the entire United States on a single CD ROM, and an additional diskette adds the GPS interface for simple route tracking. Microsoft’s Automap, best known as a route-planning program, now offers a Plus package with GPS features. Although Road Scholar’s City Streets program covers individual metropolitan areas, the firm provides updates through on-line services. Strategic Mapping’s Atlas GPS Link shares with some of the other applications the ability to add customized overlays, which can be important to a fleet manager setting up a squadron of vehicles.
How GPS Works
Between six and 10 GPS satellites are always electronically visible from any spot on earth. All carry atomic clocks, giving very precise time stamps. GPS receivers on land, sea, and air use their own clocks to determine the length of time it took for that signal to travel from the satellite. A calculation based on the time lags tells the receiver where it is in relation to the satellites.
Meanwhile, terrestrial control stations track the satellites’ flight paths and send this information to the satellites. That data is relayed to the GPS receiver, which uses it to pinpoint its own location.
The only serious flaw in this system is that the radio signals are subject to interference; heavy foliage or tall buildings can block transmission. New GPS chip technology, however, circumvents this by continuing to track the theoretical position of an occluded satellite and confirming its position when it returns to view.
Most car navigational systems start with a tiny antenna, half the size of a tape cassette, that is mounted on or near the roof of the vehicle. The antenna sends the GPS signals to a receiver, usually wired to the end of PC Card. Older PC-based receivers were connected to the computer’s serial port.
Self-contained systems, whether installed by the car manufacturer, a dealer, or the owner of the vehicle, consist of a dedicated computer and a CD-ROM reader in a unit that mounts on or near the dashboard. These project a moving map onto a display, which can range from a small LCD unit to a notebook computer’s color screen. The map moves along with the vehicle, which is represented by an arrow or other icon, following the line of the roadway on which the vehicle is traveling. Most mapping programs also trace the path of the vehicle, leaving so-called “bread crumbs” that indicate where the vehicle has been.
Among the self-contained systems are the Sony NVX-F160, which includes an antenna, a 5-inch color LCD display, a Map Disk player containing an eight-channel GPS receiver, a CD-ROM drive, and a wireless infrared remote-control device. The vehicle’s driver or passenger chooses a map from a CD-ROM of a particular region (one might include California, Las Vegas, Reno, and Lake Tahoe, for example, while another might cover the Northeast) that typically is installed under the driver’s seat. As the receiver picks up the GPS signals, a “You Are Here” cursor identifies the car’s position on a dash-mounted digital map from Etak, a Menlo Park, CA-based publisher of digital map databases and software. The Sony system, which draws power from the vehicle’s electrical system either through a direct connection or the cigarette lighter, will even
plot the best course for a given destination. The Sony NVX-F160 is priced at $2,995.
Another self-contained system, Pioneer’s GPS-X77, includes a unit that is a combination CD-ROM player, GPS receiver, and microcomputer. The system runs $2,850, while the Etak digital state maps cost $150 each.
These products can be purchased at electronic stores and high-end after-market dealers.
Unlike the self-contained systems, PC Card-based GPS receivers draw power directly from the computer, making them less cumbersome than the serial-interface units that also require an external power source. Properly recognized by the host computer’s Card and Socket Services, a GPS card becomes another serial device, working with the GPS software add-ons available with higher-end mapping programs. These products can be used with most laptops and PDAs and are generally designed for vehicular navigation.
Trimble Navigation Ltd. manufactures the Mobile GPS PC Card 110 ($695). Its antenna is connected to a two-meter coaxial cable that plugs into a socket on one end of the card. The device can track up to eight satellites simultaneously, enabling it to provide extremely accurate tracking information, particularly in urban areas.
Rockwell Semiconductor Systems, a division of Rockwell International, produces a similar product called the NavCard LP ($749), with an antenna connector. The antenna can be unclipped and snapped onto an optional socket mount. The NavCard LP can concurrently track up to nine satellites.
A Growing Consumer Market
As a car-navigation tool, GPS is getting its best exposure from car rental firms and automobile manufacturers. Hertz, for example, has begun installing a Rockwell-developed system called NeverLost in some of its midsize cars. The system features a 4-inch LCD screen and a computer voice chip that tells the driver when and where to turn in order to reach a particular destination. It also works with a cellular phone to report vehicle location to a central tracking station in case of an emergency.
Meanwhile, General Motors is offering its GuideStar system as an option to owners of Oldsmobile 88s. The system, manufactured by Rockwell’s Automotive Division, gives the driver accurate and immediate route-planning information clearly and concisely from a LCD screen attached to the instrument panel. In addition to visual assistance, the system provides simple voice prompts to aid the driver without diverting attention from the road.
As a dealer-installed option, GuideStar is priced at $1,995. It is also available through Rockwell and automotive after-market resellers under the PathMaster brand at a list price of $2,995.
Delco Electronics Corp., the automotive parts manufacturer, is taking a slightly different approach with its TelePath 100, a mapless GPS system. Instead of a map, TelePath offers motorists a compass, using the car icon as the center of reference, or arrow, to point the driver toward the desired destination. The system includes a database of addresses, including service locations like hotels. The user clicks on an address, and the pointer indicates the direction to be followed. As an added benefit, users of the Telepath 100 system who have cellular phones can select a destination from the database and, by pressing a single button on the unit, dial the corresponding phone number.
The system, which shares controls with an AM/FM stereo cassette player and radio, costs less than $1,000 and is usually installed by the car dealer, although it’s also available as an after-market item at most A.C. Delco vendors.
Ford Motor Co. is offering a GPS/cellular safety device called RESCU (Remote Emergency Satellite Cellular Unit) as an option in its 1996 Lincoln Continentals. At the push of a button, the device takes a GPS location reading and sends the information via a Motorola cellular phone to a response center, which then forwards the message to a 911 or other emergency service near the
vehicle.
GPS also is showing some potential as a traffic-management tool. Last year, for instance, the Illinois Department of Transportation joined forces with the Federal Highway Administration, AAA, and Motorola, among others, to test the effectiveness of GPS as a weapon against congestion on roadways in the Chicago area. The group tested a program called ADVANCE, for Advanced Driver and Vehicle Advisory Navigation Concept.
Under the program, a UNIX server at a base station processed information sent from sensors – including GPS receivers – installed in 100 vehicles. The vehicles were equipped with Motorola’s Mobile Navigation Assistant, which combines a touch-sensitive screen, a computer, a GPS receiver, and a CD-ROM-based map of the area.
The user enters a destination into the computer and receives ADVANCE advice about the best route to that spot as dictated by traffic conditions. Because the routing was based on real-time updates, it was subject to change at any time.
Although the tests have been discontinued, ADVANCE administrators are committed to developing the real-time aspects of the project. “This can be very important to salespeople,” says program manager Joe Ligas. “While finding an address for a routine trip is important, it is even more important to find out the best route to take to get to a destination based on real-time traffic conditions. It can help to save time.”
Sidebar: Who Else Is Using GPS?
In addition to vehicular applications, GPS is gaining popularity for a wide variety of other purposes.
Smart Carts
The Golf Club of Miami recently added 80 golf carts equipped with GPS receivers manufactured by GolfTrac of Irvine, CA. These carts show golfers the distance “within four feet” and direction from the cart to the pin.
Trunk Tracker
Filmmakers Des and Jean Bartlett took advantage of GPS on a recent wildlife-tracking expedition in Africa, using a Trimble-based system to chart the range of the endangered desert elephant.
Seeing-Eye Satellite
Arkenstone Inc., a firm dedicated to the development of services for the visually impaired, is offering a system designed to help users navigate on foot. Its Atlas Speaks and Strider package combines a speech synthesizer with a map and a GPS receiver run from a notebook PC, all of which fits into a backpack. It provides users with verbal updates of their location.
X Marks the Spot
Realtors, insurance adjusters, and tax assessors are among the targets of FieldPack Mobile Professional (FPS) software, developed by MapInfo Corp. and All Points Software. Its customizable forms allow a descriptive database to help them locate hard-to-find buildings.
Ships Ahoy
Marine and aviation users are switching from using the Loran (long range navigation) system and radio receivers to GPS for more accurate tracking of recreational and professional boats and ships. Emergency services groups are finding it an indispensable aid to rescue and forest fire-fighting operations.
Sidebar: The FAA and WAAS
The Federal Aviation Administration is working to move toward GPS-based navigation. Its Wide-Area Augmentation System (WAAS) promises more accurate routing, avoiding the inefficient zig-zags used today, and more precise tracking around airports.
The plan calls for the installing of a network of 24 ground stations to monitor and correct the data sent by GPS satellites. The current schedule anticipates implementation by 1998.
Sidebar: Glasnost Goes into Orbit
Some companies are capitalizing on a fleet of GPS satellites that were put in place by Moscow in the waning moments of the Soviet Union and which don’t suffer from “selective availability.”
Ashtech Inc., based in Sunnyvale, CA is manufacturing a GPS receiver product that will compare data received form some of the 24 American satellites circling the globe with the 24 satellites in the Russian Glonass G.P.S. network. This could be a breakthrough product because the more signals that can be compared, the greater the potential accuracy.
– possibly Mobile Office, August 1996
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