移動通信におけるTDOAを用いたINS-PX位置検出手法の提案  [in Japanese] INS-PX Method for Mobile Station Location Estimation with TDOA in Wireless Systems  [in Japanese]

Recently, Mobile Station (MS) location has been received much attention, and various services based on MS location will be provided. The methods of estimating an MS location using signals from the satellite represented by Global Positioning System (GPS) and the methods by measuring the signals from Base Stations (BSs) of the cellular phone systems are considered. If we use the GPS for location estimation in wireless systems, we must consider the problems of the receiver sensitivity. Therefore, we propose Interpolated Non-linear Solution with PX Method (INS-PX Method), which uses signals from several BSs for MS location estimation. If three or more BSs are measured, an MS location can be estimated in any cases from the combinations of a linear equation, which an MS exists in case that signals measure accurately in line of sight path, and a non-linear equation like hyperbolic curve or circle. This method is applied to TOA (Time of Arrival), TDOA (Time Difference of Arrival) and Signal Strength. In this paper, we evaluate the performance of this method through simulations under some conditions in case TDOA is measured, including the comparison with the conventional methods.