Get Your Location Fix
By Jeff Goldman, Fri Jun 13 00:00:00 GMT 2003

A number of factors are making GPS an increasingly common addition to mobile phones. In just a few years, it'll be hard to find a phone without it.

Walking through midtown Manhattan one afternoon, your GPS-enabled phone beeps as you pass a trendy clothing shop. Your phone has alerted the store to your presence at their doorstep (after you opted in to the service during a recent promotion), so the shop is letting you know that the new line of suits youd inquired about has just arrived.

While trying on a particularly sharp double-breasted pinstripe, you suddenly realize youre late for dinner across town with your wife. You grab your phone again, scroll through a few options, and select Taxi. You dont have to enter your locationyour phone does that for youand seconds later, a taxi screeches to a halt in front of the shop, you jump in, and youre off.

As the taxi approaches the restaurant, you scroll down the same list of options on your phone and select Family, then your wifes name. Instantly, her location pops up on the screenshes two blocks away, walking from the subway station. You ask the driver to pull over, pay your fare, then walk over to meet her on her way to the restaurant.

Using GPS-enabled phones, all of these services are on their way, if not already available, from a number of carriers worldwide. In many ways, GPS and mobile phones are starting to look like the perfect match.
For the time being, though, there are some bumps in the road.

Lost in the City

While GPS might seem like an eminently logical way to offer location services on mobile phones, its only one of many ways to enable such servicesand it presents unique challenges in urban areas. Significant multipath errors can be created by signals reflected off skyscrapers, and reception can be blocked out entirely as the signal tries to pass through buildings.

Since the late 90s, a number of assisted GPS (A-GPS) solutions have been available, using fixed reference receivers to improve both accuracy and reception. The results, however, have been far from perfectand with other options available, many carriers looked at triangulation technologies instead of GPS when considering location solutions for their networks.

Such technologies include E-OTD (Enhanced Observed Time Difference), which measures the time it takes for a signal to reach a network of fixed base stationsand TDOA (Time Difference of Arrival), which similarly measures the time a signal takes to arrive at a group of nearby cell sites. The key difference is that E-OTD is handset-based, while TDOA is based in the network.

Each technology has its benefits. GPS requires the addition of hardware to the handset, while the other technologies only require a software upgrade at mostalthough they demand changes to the network infrastructure that GPS doesnt require. And both triangulation technologies are less accurate than GPS, especially in rural areas where cell sites or base stations are too far apart to provide a precise location fix.

One possible solution is a combination of GPS and triangulationbut Zelos Group analyst Seamus McAteer is skeptical about the viability of hybrid solutions. I find it doubtful that well see carriers wanting support for E-OTD and GPS in a handset, he said. Theyll make a choice. Every dollars saved on bill-of-materials is a dollar in the bank.

And a number of carriers are being forced to make that choice under a very tight deadline.

Chicken,Meet Egg

In the United States, the implementation of location technology for mobile phones has been greatly accelerated by the Enhanced 911 (E911) mandate, which requires all new handsets to be capable of automatic location identification by the end of 2002. For U.S. consumers, that means the early arrival of location-based services.

Marc Prioleau, Director of Product Marketing for GPS technology company SiRF Technology, points out that location services have long been delayed by the fact that handset manufacturers dont want to build location-aware devices until services are available to make use of them, and carriers dont want to deploy services without available devices.

However, now that the E911 mandate has forced the resolution of that dilemma in the U.S., SiRF Technology anticipates an enormous jump in GPS chipset sales, from 100,000 in 2001 to over five million in 2002. Thats a lot of GPS-enabled phones deployed to satisfy E911 requirements, and Prioleau says location-based services should quickly follow.

The carriers have had to implement E911 without any real way of recovering revenue from it, Prioleau said. Now that all these location-enabled phones will be in peoples hands, there will be a big emphasis on figuring out what location services can go along with thattheres going to be huge growth in the U.S. in location-based services.

Meanwhile, the mix of standards that has long characterized the U.S. wireless industry has continued with E911. VoiceStream, AT&T Wireless, and Cingular, all GSM networks, are implementing either TDOA or E-OTDwhile Verizon Wireless and Sprint PCS, both CDMA networks, as well as Nextels iDEN network, are employing A-GPS.

Because E-OTD is built to work within the GSM standard and requires only minor software changes to implement on a GSM phone, its an easy solution for those carriers to take on. For other carriers, the availability of a low-cost A-GPS chipset for CDMA networks from QUALCOMM made GPS more attractive.

Still, Zelos Groups McAteer contends that triangulation technology will soon fade into the background. GPS will emerge as the volume leader, as its the solution that will be used by the major CDMA carriers, he said. Its being implemented and integrated on QUALCOMMs silicon, so its part of the cellular chipset: the cost issues are eased to some extent by the integration in the core cell phone silicon itself.

Service First

While U.S. carriers are struggling to keep up with the demands of E911, commercial services are appearing without government intervention in the Japanese marketthough, as McAteer points out, the higher average revenue per user in Japan makes it much easier to introduce innovative services. Theres very different structural dynamics at play in the Japanese market, he said.

A number of commercial GPS services have already been deployed in Japan using QUALCOMMs gpsOne, a hybrid version of A-GPS that includes TDOA technology. Last April, the security company SECOM launched its CoCo SECOM service, which uses a CDMA device and a gpsOne receiver to keep track of anyone or anything, from a child to a vehicle, for less than $10 a month.

Last December, KDDI released a series of GPS Keitai handsets, which have attracted over 50 content suppliers to offer location services on KDDIs networkranging from navigation solutions to location-based restaurant guides. And last month, the carrier announced its HELPNET Keitai service, which offers emergency location services and roadside assistance to KDDIs users for under $5 per month.

Meanwhile, in Europe, a number of basic location services are already available, though most use either E-OTD or TDOA, not GPS. McAteer suggests that the choice of triangulation technology over GPS in Europe has a lot to do with what he calls the not-invented-here syndromeamong other factors. E-OTD was also perceived as a lower-cost solution, he said.

Looking Ahead

Regulation will also likely affect European uptake of GPS location services: the E.U.s Enhanced 112 (E-112) initiative promises directives similar to those in the United States. Still, according to Neesha Hathi, Director of Strategic Marketing for the GSM technology company Enuvis (, Europeans will have the advantage of learning from the mistakes made by their American counterparts.

Unfortunately, what the US mandate makes the carriers do is choose a technology which is expensive and may not be as good, because they have a time limitation, Hathi said. They may choose the technology thats inferior in the endand because theyve already put in the investment, they wont want to look at a technology thats better.

Regardless, SiRFs Prioleau sees great reason for optimism in the range of handsets recently announced by companies like Nokia, Motorola, Sony Ericsson, and Samsung. Were starting to see the brand name companies introducing products with GPS, he said. The most promising thing is the fact that the guys with the real marketing clout in the wireless market are starting to put products out there.

In many ways, Prioleau sees the advent of smartphones as the best news of all for the GPS market: with so much functionality, he suggests, a new range of services will surely follow. Those phones tend to have more processing power and color screens, he said. The number of applications that can be run on them starts to increaseand that whole new market is going to lend itself very well to GPS.

Jeff Goldman is a freelance writer covering a wide range of topics for a number of online journals. He currently writes regular articles for's ISP-Planet. Brought up in Belgium, Jeff spent the last decade in New York, Chicago and London; he now lives in Los Angeles.