Location:Transforming SIM Card into Location Device

Ever since the Internet changed the world in terms of how people and businesses interact, much focus has shifted to the mobile environment. With over 2.5 billion people connected via the ubiquitous mobile phones, it is natural that the mobile phone presents a formidable and strategic access to both social and commercial interactions. Compared to the Internet environment, the mobile phone offers two key features that make it a very attractive platform to exploit: its mobility and it is personalized device.

While the opportunities are there, the hurdles to access this market are huge. Mobile phone technologies do not offer standards that allow easy development and deployment. Google’s attempt to create a new platform using Android is an indication of technology fortresses developers confront. Physically, the mobile phone will always be limited by a small screen as the visual interface so long as it wants to remain small and mobile. There is also a cost issue. Connectivity across devices is not free and this is controlled by monopolistic operators who can exert tremendous control over its subscribers. These factors present tough but interesting challenges in the mobile market.

Mobility of the mobile handset implies that the location of the carrier of the device is never static. Knowing where the device is provides another piece of information that is potentially very strategic for social and commercial purposes. Location can be used for security management, CRM or can be exploited commercially in myriad ways. The idea of using location for strategic purposes is seen as a major area for commercial exploitation. It has prompted commercial behemoths Tom- The paper describes the technology developed by agis, codenamed GprX wherein the SIM card is transformed into a location device based on the processing capability of the mobile handset alone and/or SIM cards Tom to launch a takeover of TeleAtlas closely followed by Nokia taking a strategic interest in Navteq. Both must have considered mapping to be a critical component of location services to take such high profile and costly business acquisitions in these mapping companies.

But are maps adequate for location services? The wild card for location services could in fact lie in another very simple yet critical technology – location determination. Location services cannot materialize without knowing a location in question. Until the advent of commercial GPS in the last few years, getting a location is complicated and extremely expensive. Today, GPS is regarded as de facto technology in location services. Ironically, it is a well known fact that GPS has limitations that may render the technology useless for actual service deployment in mobile devices. Mobile devices are largely carried in handbags, pouches, pockets and normally inside of buildings. They are mostly out of range of un-restricted sky views needed for GPS to work! So is the industry really ready for location services?

POSITIONING TECHNOLOGIES
Various positioning technologies have developed to ensure compliance, and/or to circumvent technological limitations of the other. The main technologies till date are GPS-phone, AGPS, terristrial based network solutions such as phone network solutions, TV signal and pseudolites. None to these technologies today are able to provide low-cost, plug & play location solution that can be easily deployed. Perhaps the closest today may be that of cell-ID location. Cell-ID is pervasive, works in all areas with signal coverage (including inbuildings) as it requires only a phone and no other technology beyond tapping services from the telephone network's backend service. The two main problems pertaining to simple Cell_ID are, firstly, it can be extremely inaccurate where the base station spacing is sparse or where the signal propagated by a base covers a large area and secondly, it requires knowledge of where the base stations. The telephone operator is in full control and no access can be granted without their permission. Operators regard such information to be confidential and are not likely to make it available.

Figure 1. Improved Cell-ID Position

Figure 3. Typical system architecture

LOCATION VIA SIM CARD OR HANDSET
The GSM base station network is a readily available infrastructure that could provide a platform for determining the handset’s location. Smart phones that are currently available have powerful processing power and data storage. Tapping on this power, an algorithm was developed by Agis to allow the handset to listen to the wireless network and generate a location.

Figure 4. Comparison of GprXTM location track superimposed on GPS track

This capability does not require any link or support from the telephone operator’s backend network services. The technology takes away the burden of relying on operator’s network services and does not require additional hardware beyond the basic mobile handset. This independence from telephone operators also means that any device may be located anywhere in the world where GSM coverage is available. In addition, it is able to locate the handset to much better accuracy than what is achievable today under similar environments. With a constrained solution, accuracy in the order of 20m is achievable under good network conditions. When operating in its base mode (single point, single base situation), the returned position is typically 60% better than otherwise achieved by traditional cell-ID methods. With GprXTM, widespread location based services (LBS) is now a real offering. Previous imple- Legend Red Circles shows the location of a moving vehicle obtained by GprXTM Blue line shows the actual track covered by the vehicle mentation requires devices operating on Symbian OS, Microsoft Mobile OS or Java-enabled phones (some hardware dependency of the PocketPC Mobile and Java devices).

GprXTM has also been ported to SIM cards. This is a significant achievement as virtually all phones may be GprXTM enabled. The SIM application has a small footprint and may be installed over the air if such services are available. The SIM solution requires server support because of its limited processing power and data storage. Another function has also been developed to detect motion of handsets. The motion detection mode will trigger an alert if the handset senses motion. GprXTM provides operator and handset independent location capability without hardware implementation on the handset. With these capabilities, GprXTM becomes a platform for pervasive and continuous location services on all phones, anytime and anywhere in the world.