Future services in wireless communications will increase the need for high bit rates in the system because of the use of "wideband" contents such as streaming video and audio. There might for example be services where the users can download movies to the car theatre system. The demands for higher bit rates combined with the ever-increasing number of users, however, introduces the need for clever and efficient usage of the limited resource of the wireless channel, by the use of properly designed transceivers. Simulations may be employed to investigate the performance of such transceivers in a cost effective way. In this paper, we discuss the basic propagation mechanisms affecting the performance of a wireless communication system and give hints and tips of how to implement these mechanisms in a simulator using Matlab.