| The studies of laser scattering by rough surface targets are widely used in the applications of military area. In this dissertation, the modeling theory of BRDF of rough surface and the numerical simulated techniques of laser scattering characteristic for the weapon system are analyzed in detail. The main contributions are shown as follows:1. The integral formulae of the scattering field and the boundary integral equations are deduced by the electromagnetic wave equations, then in terms of the integral expression obtained, the basic method, the condition and the correlation among them for scattering by kinds of rough surface are introduced. In the studies of the optical scattering from the coated medium with random particle distribution, the first-order multiple scattering approximation theory is used to simulate the laser scattering of the coated layered media with reflecting substrate.2. Based on the theory of laser scattering by rough surface, the expressions for the three parameters statistic model of BRDF are induced. According to the experimental results, this model was further modified, a more accurate model, the five parameters model, is obtained. From the view of the laser guided bomb and the laser proximity fuze weapon system, the BRDFs of surface materials for the attacked targets, such as the warship, bridge, tanks and the airplanes with fixed wing, and so on, are measured. The statistic five parameters model for three kinds of targets’materials is optimized in terms of the measured results.3. This dissertation introduced the conception of the far axis Gaussian laser beam and the division of wave front. The calculated method for the laser fuze beam scattering by rough surface applying the Gaussian laser beam theory is discussed, a self-adapted algorithm for the scattering by electrical large targets is presented, corresponding theoretically deduction is carried out, this technique is more effective and accurate.4. The geometrical modeling method of the target is studied in detail. Using two kinds of plane and general curvilinear surface, the modeling method for practical application is presented, the modeling, such as the modeling of tanks, planes and warships, is characteristic.5. Based on the plane wave spectrum spreading method and physical optical approximation, We deduced the theoretical formulas for the coherent and incoherent radar cross section of Gaussian laser beam scattering by the random shape electrical large rough objects. The calculating methods and numerical results for the reflect signals by the laser proximity fuze is also investigated in detail, especially in various miss distance and miss azimuth for some airplane with fixed wing. As a contrast, the detected signals on the condition of a cruise missile with a target together are calculated. The influence on the matching of fuze with warhead by the variety the pith-angle of the fuze detecting system is analyzed. According to the results of simulation, we presented the parameters design methods for laser near bombing fuze.6. In terms of the laser radar equations, the expressions for the reflect energy of the bistatic laser radar are concluded. During the research of signals reflecting by complex objects in half initiative laser homing weapon systems, we generalized the bistatic reflecting function which described plane objects to complex objects, and presented the conception of equivalent bistatic reflecting function. Using this conception, we deduced the formulae for calculating the target scattering of space laser. For example, the second order radiate brightness distribution on the different incident conditions of a tank is simulated, and through the discussion of the results, we obtained the following valuable conclusion:The equivalent bistatic reflect function of a tank has strongly shown Lambo’s reflecting characteristic, in the half initiative homing weapon system, for the benefit of a homing bomb to seek the targets, the laser equipment should be located above the targets.
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