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The linear mode avalanche photodiode (LM-APD) array has the capability of real-time 3D imaging for moving targets, which is a promising 3D imaging means in space. The main system parameters of the LM-APD array 3D imaging system, the characteristics of the space target itself, and the relative positional relationship between them will affect the 3D imaging results at the same time, and there is a need for an appropriate simulation method to describe the space target point cloud acquired by the LM-APD array 3D imaging system under different conditions. We propose a simulation method for the 3D imaging of space targets with LM-APD arrays, which takes the characteristics of the space targets and the relative position into consideration, and build a link from the laser to the receiving system to simulate the echo waveform of each pixel in the LM-APD array. The experiment results under different conditions show that the proposed simulation method can accurately describe the imaging results of the LM-APD array 3D imaging system for space targets with different shapes, materials, and motion states, which providing theoretical and data support for the design of LM-APD array 3D imaging systems.

For classical TCAR(three carrier ambiguity resolution) algorithm is affected by ionospheric delay and measurement noise, it is difficult to reliably fix ambiguity at medium and long baselines. An improved TCAR algorithm which takes the influence of ionospheric delay into account and has good adaptive robustness is proposed. On the basis of the non-geometric TCAR model, ionospheric delay is obtained by linearly combining extra-wide-lane with fixed ambiguity, and then wide-lane ambiguity is solved. Solving narrow-lane ambiguity by adaptive robust filtering by constructing optimal combination observation, which can effectively improve the fixed success rate of narrow-lane ambiguity and reduce the adverse effects of gross error. Experimental results show that the improved TCAR algorithm can guarantee a high fixed correct rate of wide-lane ambiguity, effectively improve fixed success rate of narrow-lane ambiguity, and has a good ability to resist gross error.

Decimeter-level service is provided by the BeiDou satellite navigation system wide area differential service (BDS WADS) for users who collect carrier phase measurements. However, the fluctuations in Geostationary Earth Orbit (GEO) satellite orbit errors reduce the spatial correlation of orbit errors. These fluctuations not only decrease the accuracy and stability of zone correction service provided by BDS WADS, but also shorten its effective range. In this paper, we proposed an algorithm to weaken the influence of GEO satellite orbit error fluctuations and verified the method using data from eight sparsely distributed zones. The results show that orbit errors can be stabilized using orbit fluctuation corrections, and the positioning precision and stability of the BDS WADS can be improved simultaneously. Under normal circumstances, the horizontal and vertical positioning accuracy of users within 1000 km from the center of the zone can reach 0.19 m and 0.34 m. Furthermore, the effective range is increased. The positioning performance within 1800 km could reach 0.24 m and 0.38 m for the horizontal and vertical components, respectively.

The carrier-based aircraft system is the core component of modern aircraft carrier combat system, a maritime platform for carrier-borne fighters, whether carrier aircraft can demonstrate combat power depends on the ability of the carrier-based aircraft to take off and landing. In order to improve the safety and reliability of shipboard on warship, this paper aims at GNSS/INS/Photogrammetry integrated navigation theory, discussed from the basic level of integrated navigation system on implementation and the performance of the whole positioning. The mainly research is when satellite is not available, the inertial navigation error is corrected by the positioning of the Photogrammetry, to achieve high accuracy, high reliability and data refresh rate. The multi-rate kalman filter method is used to deal with the problem of the non-equal intervals between the INS and Photogrammetry. Finally, by simulating the accuracy of the integrated navigation positioning of INS/Photogrammetry by multi-rate EKF filter, to verify the feasibility of the aircraft landing/carrier landing.