Navigation using a personal mobile device (such as a “smart” cell-phone) is commonplace, and mostly makes use of satellite based global positioning systems (e.g. GPS).
While navigation (i.e., finding one's way from the current position to a desired destination) was the “raison d′etre” for positioning technology, the capability of determining and sharing the positions of object, and in particular one's self-position spawned a myriad of other applications and services, such as Surveying and Mapping, Location Based Services (LBS) and advertisement, Social Network applications, people and vehicle tracking, etc. All this has made positioning technology very popular, and it is installed in all modern mobile devices.
Satellite GPS technology is very attractive because the vast majority of GPS receivers are relatively simple and low cost, and the required satellite signal is globally available, without the need for any additional hardware or infrastructure installation. However—it becomes useless in areas where the receivers cannot “see the sky”, or are otherwise deprived of adequate satellite signal.
Indoor shopping malls, airport terminals, trade show and exhibition venues, museums—these are just some of the venues where position based applications can be extremely useful, but where GPS technology cannot work, and one has to look for other technologies that can do the task. Existing indoor positioning technologies are mostly based on radio signals, such as WiFi, which also happens to be available in most modern mobile devices. However, these technologies lack adequate precision, or require costly hardware infrastructure installation and maintenance throughout the area where positioning is desired.