Modern military airborne radars are highly sophisticated, multi-mode systems which are required to detect difficult targets in all aspects and over a large range/velocity detection space. There are particular difficulties associated with the airborne case such as the limited antenna aperture, high platform velocity and severe clutter levels which present difficult waveform design challenges. This tutorial will consider the design parameters of high pulse repetition frequency (PRF) and medium PRF waveforms commonly used in airborne pulse Doppler radar modes. The majority of this tutorial will be devoted to the issues concerning the selection of the number of PRFs and of the PRF values used in the medium PRF mode. PRF optimisation methods using evolutionary algorithms used by the author and his colleagues in a number of recent studies will be described. Examples will be given of airborne fire control radars, airborne early warning systems and active radar seekers used in anti-aircraft missiles.