Wi-Fi as a part of LBS
Wi-Fi Positioning System (WPS) uses wireless fidelity network instead of GPS or cell tower systems or location beacons to determine position. This consists of a nation wide access points or network of location beacons used for pinpoint measurement of user’s position and is better than satellite positioning system. There are several Wi-Fi positioning software available that uses radio signals emitted from wireless routers to determine the exact position of any Wi-Fi enabled devices including PC, laptop, PDA and smart phone.
To simply define the function of Wi-Fi network, the best one is to take walkie-talkie. In Walkie-talkie there are small radios that can transmit and receive radio signals. It first encodes voice signals into radio signals then transmits radio frequency to another walkie-talkie through antenna. The other one receives radio signals and then decodes it into voice that can be heard in speakerphone by the user.
The operator that provides Wi-Fi services has their own database containing information about every access points in a particular area. So when a user enter into a area then the software search for access points and then calculates the exact position of the user by selecting and comparing them to the reference database. For more accuracy, there needs to be more access points with more Wi-Fi signals.
Wi-Fi is also used in connecting computer in the network together. By the use of emitted radio signals one can connect computers without wire anywhere in home or office. But this can be possible within a distance of 100 meters. Here, Wi-Fi enabled devices first transmit the binary codes of the computer into radio waves and then transmits it to the other computer where the attached Wi-Fi device again converts it into binary code for the respective computer.
Apart from establishing connection between computers in home or office, the Wi-Fi software can also be used to provide better driving direction in cities, to locate any particular business points, to track stolen equipments like laptops or even motor vehicle attached with Wi-Fi receiver.
Comparison with GPS:
As far as its comparison with GPS that uses satellite signals is concerned, its is as accurate as GPS and is more reliable and useful in urban areas where GPS is not that much of helpful due to buildings structure that makes the signals bounce back leading to inaccuracy. Again it does not provide any coverage inside a building. GPS only determines the location of object within a few hundred meters but Wi-Fi can locate within 20 to 30 meters of an object depending on the deployment of routers. So, it is one of the most important wireless networks under location-based service used for determining positions of an object or person.
Drawbacks: As its accuracy depends on the density of Wi-Fi signals or the number of routers, the technology perfroms better in the urban areas that have more Wi-Fi beacons. It is not popular in rural areas where access points are deployed far from eachother. Again unlike GPS satellites or cell towers, the Wi-Fi routers move from one place to another by the user and it becomes necessary to timely update the location database by searching new Wi-Fi access points in a aparticluar area and only then the software can locate the precise position.