Imaging laser radar is a new type radar with vast potentials, that it can provide echo intensity image, range gating image, velocity image and three-dimensional image of the target at the same time. In order to improve its performance, to combine the polarization spectral detection technique with the imaging laser radar technique is worth studying. In this paper, the author studies the characteristics of laser echo using the method of modeling, as well as the theories of Stokes parameters and Mueller matrices. In the first place the author derives a polarized bidirectional reflectance distribution function (polarized BRDF) model that simulates the polarimetric of the laser echo from the basic theory with established scalar BRDF models. Then it makes a simulation of all the process of the model construction and compares the results to the experiment data. With the results of comparison it makes corrections of some parameters in the polarized model and obtains a relatively correct polarized model in the end. At last, the author induces the characteristics of laser echo with some main influence factors.
The complex index of refraction was the fixed characteristic of the target material. In the remote sense field, the complex index of the refraction is a useful parameter for classify and recognize the material. To detect the complex index of the refraction of the opaque material was difficult. A new method of estimating the complex refraction index based on the measured polarization degree of the material according to the different incident angle of reflectance angle was provided. The result showed that the stability and reliability of the acquired complex refraction index was fine.
In the test for the laser seeker in the hardware-in-loop simulation, acquiring the effect of polarization laser echo wave to optical stress polarization of the seeker and to the polarization guidance performance was not considered. A new method to generating the dynamic polarization laser echo signal was provided based on the scene model; furthermore, the method to adding the polarization characters to the energy scene was introduced. At last, the insufficient of the method to generating and simulating the dynamic polarization signal was analyzed.
In this paper, we try to find a model that can apply to predict the polarization characteristics of the targets on the ground correctly. In the first place, we give an introduction to several kinds of existing models which are divided into three categories: Empirical models are precise but occupy too much source of computer; Physical-based models can predict the phenomenon of reflection exactly but hardly get the final results; Semi-empirical models have both advantages mentioned above and avoid their disadvantages effectively. Then we make an analysis of the Priest-Germer（PG）pBRDF model, one of semi-empirical models, which is suitable for our study. The methods of parameters inversing and testing are proposed based on this model and the test system from which we can get enough data to verify the accuracy of the model is designed independently. At last, we make a simulation of the whole process of the parameters inversing based on PG pBRDF model. From the analysis of the simulation curves, we briefly know the direction we go in the following work to make an amendment.