System level evaluation of cooperative MIMO-OFDMA-based heterogeneous networks

Coordinated multipoint transmission (CoMP) is considered for a heterogeneous network where different kinds of base stations (BSs) are located. We present a system level simulator for investigating the gains that can be achieved from the use of cooperative transmission (CoMP) in an urban heterogeneous cellular environment. It is shown that the spectral efficiency of the users located within a macro-cellular environment may significantly increase by employing low-power nodes (femtocells). On the other hand, the spectral efficiency of cell-edge users is decreased due to the additional inter-cell interference introduced by the use of such femtocells. Furthermore, it is shown that significant gain can be achieved by the cooperation of the BSs. From a users point of view, the inter-cell interference is reduced, and thus, the spectral efficiency per user can be significantly enhanced.