A mobile station positioning algorithm using forced handover

Mobile communication has become livelihood in many applications. Mobile Station (MS), or rover, positioning using mobile communication system has been investigated vastly for personal security and emergency purposes. Many methods using wave propagation from mobile base stations (BS) were developed. The solution accuracy is still beyond practicality. This paper presents a forced handover method to detect four base transceiver stations (BTS) with time of arrival loci to determine their intersection area for possible location. A special subscriber identity module (SIM) is used to install four different system providers' subscribers. An algorithm is formulated to carry handover control and calculate their timing advance (TA) from each BTS. A BS database is established from the supports of system providers to set up reference locations in positioning. From several experiments, the estimated positions are compared with global positioning system (GPS) data with fairly good results to get into 30 meters. However, it still takes minutes to get a result. The proposed method and algorithm is feasible toward practical implementation.