Airport Lidar Wind Shear Monitoring System

Wind shear is an atmospheric phenomena that the speed or direction of wind changes suddenly in horizontal or vertical directions. With features as very short duration, great wind strength and small-scaled wind field, airport wind shear has brought great difficulties for modern air transportation and detection for early warning. LIDAR, as one of airport usually used atmosphere and meteorological monitoring systems, urgently need to further realize the function of rapidly, real-time, accurately monitor and predict wind shear phenomenon. To reduce the costs of upgrading of existing LIDAR system and research of new wind shear monitoring system, this paper according to the characteristics of the low-level wind shear at the airport and its detection requirements to establish a design and verification LIDAR wind shear monitoring system software in the form of a module. The way of reconstructing dynamic working process of the LIDAR system and simulating its detection results to analysis LIDAR performance index and wind field detection index would do technical support for airport wind shear detection with LIDAR and LIDAR system upgrade.The design and verification software of this paper is divided into several main modules: Transmitter module according to the signal form and modulation way to produce transmitting signal suitable for wind field detection. In this module, you can set the power, modulation parameters and transmitting antenna parameters; Antenna scanning module according to a certain scanning way to scan the near-earth space, you can configure the antenna gain, beam width and scanning range, etc. you can configure the scanning parameters and scanning speed; Wind field module includes wind shear model, clutter and noise model. You can set parameters as wind field radius, location, distortion factor and clutter unit numbers. Receiver module includes detector module and data preprocessing module, you can configure the receiving antenna parameters and detector parameters. This paper use heterodyne detector and intermediate frequency processor to implement; Signal processing module need to extract target signal from the echo signal of clutter and noise and inverse it, including clutter suppression module, spectral moment estimation module and wind field inversion module, clutter suppression, spectral moment estimation and wind field inversion steps. Clutter suppression can be implemented by Doppler filter group. Usually signal accumulation is necessary before the filter group. For wind shear echo signal, FFT is an effective method to estimate the power spectrum of the echo signal. Wind field inversion module uses a combined method of least squares method and the adaptive genetic algorithm to implement. Then, combine these modules and use Simulink tools to implement the software framework and analysis the performance.On the basis of the software framework, study and compare the methods involved in each module, and design and verification of the overall framework. By changing the radar system technical index of the design and verification software, we can analyze the detection performance for the same wind field and find the most suitable index for detecting this wind field; For a given set of indicators, we can analyze the detection results of different wind field and evaluate the detection performance by the design and verification software. Call different wind field inversion modules of the design and verification software to analysis the fitting results of radial velocity gotten by different inversion algorithms can evaluate the accuracy and real-time performance of the algorithm. By verification and analysis, it shows that the software framework designed in this paper has preliminary application value.