Design And Simulation Of Aircraft Landing Navigation Sensor Signal Processing Scheme

High-speed unmanned aerial vehicle demands high Real-time position orientation accuracy, so in order to save development costs, reduce systemic risk, it is necessary to verify the system scheme ahead of schedule combined with apiece guidelines of its signal processing system. In allusion to the specialties of a new type unmanned aerial vehicle's apiece operation phases before landing and its signal processing scheme's design background, this paper's main works are designing signal processing system scheme of the attitude sensor and verifying the scheme's feasibility through simulation analysis. The material schemes designed including three parts a follows: Pulse signal is adopted for the beam irradiation region DBS imaging process during the aircraft's far operating phase, and the distance along the axes is estimated with the utilization of both distance-dimensional and azimuth-dimensional information. In order to avoid problems such as Doppler broadening and inadequate resolution of Doppler filter in usual PD process, radial velocity information of the center beam is estimated by correlation function method in time domain. Range walking correction process, together with the use of smoothing treatment and the threshold detection technique based on the normalized extent(normalized threshold median method), is adopted in the imaging processing to improve the accuracy of distance measuring. While the aircraft at its near operating phase, because the antenna gain is symmetrical relative to the beam center, consider center frequency point of the beam center as the center, the energy integral of echo spectrum envelope should be equal on both sides of it. So the frequency domain equal energy wave door method with frequency modulated continuous triangular wave system signal is designed for estimating the distance along the axes and the radial velocity through two range wave doors scanning the main valve area of the echo while sliding. Finally, during the aircraft's hovering phase before landing, because the dust size is much smaller than the wavelength of millimeter wave and will not significantly affect the radar job, and the identification ability of the scene's height is of the main interest, synthetic narrow beam real aperture radar imaging scheme and the final landing site's searching and selecting methods are designed with the adoption of linear frequency modulated continuous wave signal in order to obtain the terrain information at close range and select the final landing site.