Investigation of lidar backscatter including depolarization and higher scattering orders

A lidar signal model of the depolarization of the backscatter signal, which takes into account direct backscatter as well as other scattering phenomena of aerosol particles, was developed. Special attention was paid to pulse times. An inversion method for the determination of the particle densities from the model parameters is presented. In order to verify the model, tests were performed with a monostatic single-wavelength lidar system. The analysis of the signals shows different effective extinction coefficients, the interpretation of which requires higher scattering orders. It is shown that the approximation of aspherical particles by homogeneous spherical particles is not possible for the description of the lidar backscatter signal. The measurements are found to be in excellent agreement with the theoretical signal parameters for scattering on homogeneous spherical droplets in clouds.