Location based services
Location-based services (Engl. Location-based Services (LBS) , including: Location Dependent Services (LDS) ) are mobile services , which with the aid of position-dependent data provides the end user selective information or provide services of another kind.
How user positions are technically determined can be looked up under the item Position determination method.
A distinction is made between reactive and proactive location-based services. In the case of reactive services, the service user must explicitly request the service (e.g. RestaurantFinder). A proactive service reacts to certain events, for example when entering a certain zone.
In order to be able to offer location-based services in practice, various actors need to work together:
- Terminal e.g. B. Mobile phone ; OBU2
- Position determinator carries out the localization and the position calculation of the target object. In the case of terminal-based location methods, this role is assumed by the target object. In the case of network-based positioning, however, this role is usually taken on by the operator of the positioning infrastructure. This service presents the raw position data of the target object mostly in a form of representation that depends on the location method used.
- Location determiner prepares the data supplied by the position finder in such a way that they can be conveyed to a service provider. This is e.g. B. a mobile network operator based on Global System for Mobile Communications (GSM) or Universal Mobile Telecommunications System (UMTS), which processes the data that could be determined based on the proximity of a terminal to a base station.
- The service provider uses this information to process it further according to the service (e.g. combination with geographical data), transmits the resulting data to the service user and ultimately makes the service available, e.g. B. Toll Collect
- The service user sends the requests to the service (e.g. via mobile phone or PC )
New location-based social networks are able to provide all information with a current position, whether it is messages, photos, videos or self-created POIs . With these new services, subscribers in social networks can see at any time where a family member or friend is or locate their vehicle in a parking lot. Current smartphones are often equipped with (A) GPS and WLAN for location determination, even in buildings. There are many techniques for determining location data (GPS, GSM, Bluetooth, RFID, etc.). A general model for this problem has been developed at Radboud University Nijmegen (The Netherlands).
Location-based services in mobile communications
Location-based services are offers that are made available to the user of a mobile phone depending on their position.
In order to be able to offer this service, one tries to fall back on devices that have already been used in order to determine the position of the customer (user / subscriber). A mobile phone is particularly suitable for this, as a medium there already knows the position of the end device - the mobile network .
In the Home Location Register (HLR), the network stores the Visitor Location Register (VLR) in which the mobile terminal (cell phone) is currently located. This VLR in turn knows the location area (LA) in which the mobile terminal is located. With this information you can use a table to determine which coordinates these are. The so-called cell identification number (usually an antenna mast serves several radio cells at the same time) can be used for more precise positioning . The accuracy here depends on the size of the radio cell. In heavily populated areas, small cells must be planned and built in order to serve all customers. These cells have a typical size of 300 to 500 m (radius). In this area, the localization via the cell data is more precise than, for example, in the country, where large cells are planned and built. These can have a radius of a few kilometers up to 15 km.
Improvements in accuracy can be achieved through triangulation or the use of information about the signal propagation time and the reception field strength, as well as through the use of techniques such as the Global Positioning System (GPS) or Assisted Global Positioning System (AGPS). Some applications can use multiple technologies to optimize accuracy and calculation time.
With the mobile Internet service Wireless Application Protocol (WAP), via HTML or even small applications (apps), suitable services can be offered on the end device and enable interaction.
Examples
- Nearby points of interest , Point of Interest (POI)
- Where am I
- Where are my friends
- Are my friends here
- My child leaves the target corridor
- Route guidance, route planner and route optimization
- Travel time forecast (through group tracing and accumulation analyzes)
- Mobile time recording
- Location based games, online scavenger hunt
- Location based advertising and communication
- Industrial, location-dependent process controls
- location-based games, e.g. B. Geocaching , Ingress , Foursquare
In order to protect the privacy of the users and to prevent misuse, the mobile phone providers are obliged to ask the subscriber for his consent for an intended localization. Exceptions to this are situations in which there is a current danger to the life or health of a person. The legal basis is in Germany in the Telecommunications Act (Germany) ( Section 98 ), in Austria in the Telecommunications Act (Austria) ( Section 93 , Section 96 , Section 102 ) and the Security Police Act (Austria) ( Section 53 (3a)), it is an administrative penalty of up to € 37,000 earmarked for violations ( Section 109 ).
Working principle
Example POI:
- A subscriber calls up the service in his WAP browser , he is looking for cinemas.
- The number of the mobile radio subscriber is known to this service (a web server ) (by the network operator).
- The service now sends a request to a server that can determine the location of a participant.
- This server sends a location query to the cellular network
- In order to enable current localization, an invisible SMS is sent to the end device (mobile) or so-called paging is carried out by other means
- In order to distribute this SMS, the network must update the location data (paging).
- The cellular network replies to the server with information about the antenna that is closest to the mobile.
- The server uses a table to determine the coordinates, the radiation angle and the signal range.
- With these values the server can now determine the approximate position of the participant in which the cell center is used.
- Now the service (POI) compares the coordinates received with the data in its database in order to find the nearest cinemas.
- The participant is now shown a list of cinemas in their immediate vicinity.
- Another service can now also give the participant directions to the cinema of their choice.
Another conceivable extension would be, for example, that you could order and pay for cinema tickets directly with your mobile phone, no longer have to go to the cash desk and be automatically recognized at the entrance based on your position and gain access.
criticism
Jerome E. Dobson and Peter F. Fisher point out the possibility of misuse of the data required for location-based services and coined the term "Geoslavery" for this. Data protection advocates therefore recommend the situation-specific deactivation of the permanent forwarding of your own location.
See also
Web links
- E-LBA research project of the European Union on location-based advertising
- English-language introduction to Location Based Services (pdf; 2.62 MB)
- Animated short film about LBS.
- International Symposium LBS and TeleCartography, 26. – 28. November 2008, Salzburg, Austria
- Location Based Mobile Networking white paper (1.94 MB) (PDF file)
- Location-based mobile game as a project at the Augsburg University of Applied Sciences
Individual evidence
- ↑ Positioning techniques: A general model . Radboud University of Nijmegen. Retrieved February 16, 2011.
- ↑ Jerome E. Dobson, Peter F. Fisher: Geoslavery (PDF; 776 kB), IEEE Technology and Society Magazine , 22 (1), 2003, pp. 47-52.
- ↑ Your own location is an asset worth protecting! ( Memento of the original from October 24, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved November 14, 2013
