Precise Point Positioning And Inertial Measurement Integrated Navigation System Enhanced With Multi-Sensor

Integration between the Global Positioning System(GPS) and Inertial Navigation Systems(INS) are increasingly used for the various high precision navigation information(position, velocity and attitude). This has been investigated over the past decades in different applications area, such as military, agriculture and so on. The dissertation mainly focuses on the integrated navigation system between precise point positioning and inertial measurement, which includes the correction model of precise point positioning, the model of adaptive federated filter, the integrated navigation between precise point positioning and inertial measurement, inertial aided cycle slip detection and repair for precise point positioning, enhanced integrated navigation system with odometer based on fuzzy neural network. The main work and contributions are summarized as follows:(1) A novel alignment method for disturbed base is proposed with the aid of a Vondrak low pass filter in the paper. The spectral analysis is processed to comparing the error characteristic of INS force observation between on stationary base and on disturbed bases. A Vondrak low pass filter is constructed based on spectral analysis result. Furthermore, simulated experiment and actual experiment were performed to validate the new algorithm. The results indicate that the Vondrak filter could eliminate the high frequency noise in the force observation.(2) The main difference between precise point positioning and differential positioning is more error sources need to be corrected in the precise point positioning solution. We analyze the error characteristics and mechanism of PPP and provide the correction model. The influence of different correction medel on precise point positioning is studied using the observation with different sampling frequency, which can provide some references for model selection.(3) In multi-sensor integrated navigation, extensive observation information, low computational efficiency and weak robust ability will lead poor navigation resolution. An adaptive federated filter is been proposed. The equivalence property between federated filter and adaptive filter is proved and the establishment of the equivalent conditions is built. The information allocation factor of adaptive federated filter is constructed. The results of the experiment indicate that adaptive federated filter shows well robust performance and high efficiency in computations.(4) Within the advent of precise orbit and clock products, the integrated navigation system between precise point positioning and inertial measurement is presented in the paper. Because the kinds of measurements(pseudorange, carrier phase and Doppler) are many, an adaptive federated filter method is applied to improve the filter efficiency and adaptivity. The results indicate that INS can increase the un-differenced GPS position accuracy and the proposed algorithm can improve the position, velocity and attitude accuracy. The proposed method can decrease the associated computer burden and eliminate the influence of dynamics model error.(5) An inertial aided cycle slip detection and repair method is proposed to obtain higher accuracy navigation information. The inertial information is introduced the traditional Melbourne-Wübbena combination observation to remove high noise and multipath from pseudorange. Detail error analysis is given to determine the critical value of INS position accuracy which makes inertial aided Melbourne-Wübbena combination has better performance. The results indicate that the inertial aided decision variable has higher accuracy than the Melbourne-Wübbena decision variable. The proposed scheme can efficiently detect and repair the cycle slip.(6) The paper presents an enhanced integrated navigation system with UWB. When the GPS signal is covered, UWB is used to acquire the range information. The filter observation is constructed by UWB distance information and GPS original observation. The number of filter input is inceased, which solve the problem that the satellite number is not enough. The introduction of UWB range can improve the spatial structure of observation information and decreace the PDOP value. The results indicate that, the proposed method can improve the position accuracy and reliability, when GPS signal is partial covered.(7) The paper presents an enhanced integrated navigation system with odometer using fuzzy neural network. According that the measurement type of GPS and Odometer is the same, the topology of an FNN is constructed. The information from GPS, Odometer and IMU is input in FNN system for network training during signal availability, while the FNN model receives the observation from IMU and Odometer to generate Odometer velocity correction to enhance resolution accuracy in long GPS outage. An actual experiment was performed to validate the new algorithm. The results indicate that, the proposed method can improve the position, velocity and attitude accuracy in long GPS outage.