Résumé
We present results of Monte Carlo simulations for the Cherenkov Telescope Array – the next generation observatory of very high energy gamma rays. These calculations are intended to verify design concept for various elements of the array: single telescope design, camera electronics, array configuration, camera and array trigger, etc. The simulations consist of two parts: simulation of the distribution of Cherenkov photons from atmospheric air showers and calculation of response of the telescopes during the detection process. In design study phase of the experiment a large amount of simulations of air showers has been performed with the use of EGEE grid infrastructure, especially centers in Lyon and ACC Cyfronet AGH. Currently we are investigating the details of design of a small telescope – one of several kinds intended for the array.