The wireless communication systems has gone from different generations from SISO systems to MIMO systems. Bandwidth is one important constraint in wireless communication. In wireless communication, high data transmission rates are essential for the services like tripple play i.e. data, voice and video. At user end the capacity determines the quality of the communication systems. This paper aims to compare the different RF wireless communication systems like SISO, MISO, SIMO and MIMO systems on the capacity basis and explaining the concept as today, the wireless communication has evolved from 2G, 3G to 4G and the companies are fighting to create networks with more and more capacity so that data rates can be increased and customers can be benefitted more. The ultimate goal of wireless communication systems is to create a global personal and multimedia communication without any capacity issues.