System design of an ultra-tight MIMU/software receiver integration

In order to improve the performances of software receiver, an ultra-tight Micro-Inertial Measurement Unit (MIMU)/software receiver integration method is studied. The nonlinear tracking loop filter and integrated navigation filter are designed by analyzing the nonlinear characteristics of receiver tracking loop and MIMU. The performance of closed-loop ultra-tight integrated system is evaluated by experimental software receiver and Micro-Electro-Mechanical Systems (MEMS) inertial data collected in real dynamic environments. The results show the improvement in the performance of the tracking loop in this ultra-tight aided configuration under faintish In-phase/Quadra-phase conditions.