The paper is focused on the comparison of Top Hat and Gaussian beam properties from the perspective of received optical power. Gaussian beam is very well known, so there isn't necessary to describe it, on the other hand Top Hat beam, which is created from Gaussian beam, isn't used so widely. Creation of Top Hat is briefly described in this contribution. The main point of the contribution is comparison of received optical power of both types of beams when the beams are redirected by transmitter motion or atmospheric transmission media. Calculations are provided for four receiving lens diameters.