In the search for understanding the formation and evolution of a solar system, terrestrial planets & any exoplanetary systems, the understanding of the evolution & formation of giant planet's play a crucial role. The primary goal is to study the atmospheres, their physical & chemical processes governed by gases, clouds, and hazes. This research focuses on developing a new technique to characterize aerosol particles using a nephelometer. The new forward model is a two-part model, in the first part, an atmosphere radiative model for Saturn & Venus is developed and the polarization internal field is evaluated using Monte-Carlo technique. The second part of the model is to demonstrate the feasibility of the new instrument technique developed in first part using space system engineering approach. The research concludes that the forward model developed could be used to evaluate the internal polarization field of any planetary atmosphere. The feasibility study of new instrument technique for Saturn’s atmosphere demonstrates a possibility to derive the vertical structure up to 2[bar] pressure & for Venus’s atmosphere in all layers.