Research on Influence of Charged Sand Atmosphere on the Performance of Ku and Ka Band Radar

In arid and semi-arid areas, in the atmosphere carrying sand particles, in order to make the radar work all-weather, it is necessary to research the properties of microwave propagation in the sand atmosphere and the impact on the radar performance. The absorption, scattering and backscattering of sand particles carrying different size and different charge are analyzed by Mie theory. At K and Ka band, using the log-normal particle size distribution spectrum in sand atmosphere with different visibility, the specific attenuation and the backscattering per unit volume of charged sand particle are studied. Based on meteorological radar equation, the radar echo power and radar reflectivity are analyzed, and the relations between they with visibility and particle charge are given. The results show that the charged particle in the sand atmosphere increases the microwave attenuation. The attenuation reaches a maximum when the charge-to-mass ratio is about 50uC/kg. When the amount of sand particle charge increases, the backscattering factor increases. The radar echo power of the sand atmosphere increases with the decrease of visibility, but when the distance is greater than a certain distance, due to the increase of attenuation, it decreases with the visibility decrease. The effect of charged particle in sand atmosphere becomes larger with increasing frequency and distance. This study can lay a good foundation for radar detection in sand and dust atmosphere, and inversion of the physical properties of the sand atmosphere.