Loosely Coupled GNSS/INS for Android Platforms

Recently, smartphones have begun to be equipped with a large number of sensors, some premium phones contain more than 15 sensors, this number will increase with the progress of Microelectromechanical systems (MEMS) technology which affects the improvement of other sensor technologies and lead to updated usage status. These sensors could be used in different activities during daily human life such as user interface healthcare, mobile gaming, survival, tracking, and navigation. Some of the integrated sensors form a completely Inertial Measurement Unit (IMU) which could be used to aid the Global navigation satellite system (GNSS) localization and also the implementation of an integrated navigation system (GNSS/INS). A 15-state Extended Kalman Filter (EKF) in a loosely coupled (LC) MATLAB algorithm was used to integrate the data from GNSS and smartphone sensors. The result of the field test has shown that the smartphone sensors can effectively fill the positioning gap and provide an accurate position during the presence of GNSS signal and short time GNSS outage, which gave a sufficient position error however this error increased when the GNSS outage increased.