Location-based services

Location-based services (LBS) are a general class of computer program-level services that use location data to control features. As such LBS is an information service and has a number of uses in social networking today as an entertainment service, which is accessible with mobile devices through the mobile network and which uses information on the geographical position of the mobile device. This has become more and more important with the expansion of the smartphone and tablet markets as well.

LBS include services to identify a location of a person or object, such as discovering the nearest banking cash machine (a.k.a. ATM) or the whereabouts of a friend or employee. LBS include parcel tracking and vehicle tracking services. LBS can include mobile commerce when taking the form of coupons or advertising directed at customers based on their current location. They include personalized weather services and even location-based games. They are an example of telecommunication convergence.

LBS include applications that depend on the user location to provide a service/information that is relevant to the user at that location. LBS normally use mobile devices with positioning ability to provide the service or information to the user. LBS can be used for personal or professional purposes.

Several categories of methods can be used to find the location of the subscriber. The simple and standard solution is GPS-based LBS. GPS is based on the concept of trilateration, a basic geometric principle that allows finding one location if one knows its distance from other, already known locations.

GSM localization is the second option. Finding the location of a mobile device in relation to its cell site is another way to find out the location of an object or a person. It relies on various means of multilateration of the signal from cell sites serving a mobile phone. The geographical position of the device is found out through various techniques like time difference of arrival (TDOA) or Enhanced Observed Time Difference (E-OTD).

Many other Local Positioning Systems are available, especially for indoor use. GPS and GSM do not work very well indoors, so other techniques are used, including Co-Pilot Beacon for CDMA Networks, Bluetooth, UWB, RFID and Wi-Fi.

Some examples of location-based services are:

· Recommending social events in a city;

· Requesting the nearest business or service, such as an ATM, restaurant or a retail store;

· Turn by turn navigation to any address;

· Assistive Healthcare Systems;

· Locating people on a map displayed on the mobile phone

· Receiving alerts, such as notification of a sale on gas or warning of a traffic jam;

· Location-based mobile advertising;

· Asset recovery combined with active RF to find, for example, stolen assets in containers where GPS would not work;

· Сontextualizing learning and research;

· Games where your location is part of the game play, for example your movements during your day make your avatar move in the game or your position unlocks content;

· Real-time Q&A revolving around restaurants, services, and other venues.

27. Give a short summary of the text above.

28. What kind of LBS are useful for…

- drivers?

- gamers?

- tourists?

- ordinary people?

UNIT 3