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The popularization of smartphone and continuous upgrading of configuration make the 4A target (anytime, anywhere, anybody and anything) for location service become possible. Pedestrian navigation based on smartphone is an ideal solution for indoor and outdoor seamless positioning. Mobile navigation electronic map is the basis of pedestrian navigation. A smartphone seamless positioning system based on outdoor and indoor mobile navigation electronic map is proposed in this paper. Indoor map adding seamless connection between indoor and outdoor geographic information, which is convenient for initial position determination and heading constraint. The inertial sensors and GNSS module are combined to complete the navigation solution, and the navigation software is designed in eclipse environment. The Baidu map software package is used to carry on the secondary development to support the solution and display. The experiment verified the feasibility of the smartphone seamless positioning system, which can real time display the navigation solution and work dead zone free.

High-performance dynamic angle measurement is an intensively researched subject, which has wide applications in various fields, such as satellite antenna, long distance telescope, etc. However, few goniometers can fulfil all the requirements of wide input range, high precision and high dynamic. Non-Planar Four-Mode Differential Ring Laser Gyroscope (NP-FMDRLG) is the so-called "next-generation" of Ring Laser Gyroscope (RLG), which is of high-precision and has no mechanical dithering parts, meeting the needs of almost all the high-performance angle measuring fields. NP-FMDRLG has no mechanical dithering parts and therefore no reaction to the rotation axis of the unit under test, feathering very low non-linearity of the scale factor, and can fulfil the measurement needs of both large and small angle, both fast and slow rotation rates. Theoretically, this paper analyzes and concludes that the bias drift is the most significant factor to the high-dynamic and high-precision angle measurement. Angle measuring precision of less than 1 arc-second is theoretically verified and experimentally demonstrated with former error analysis and field experiments. Furthermore, utilizing the ultra-high-precision rotation table SCMS-107 of the National Metrology Institutes of China (NMI), a dynamic angle measuring precision of 0.121 arc-seconds is experimentally verified. Due to the advantages stated above, NP-FMDRLG is an ideal goniometer for all high-performance and high-dynamic angle measurement areas, such as numerically controlled machine tools, high-precision rotation tables, satellite antennas, long-distance telescopes, pointing applications, etc.