Coordinateci multi-cell downlink transmission utilizing transmit antenna geometry

This paper investigates the multi-cell downlink system in which multi-antenna base stations (BSs) utilize antenna geometry to provide coordinated transmission. For each BS, we partition the antennas into two clusters, with one cluster serving an in-cell user, and the second clusters of all BSs cooperatively serving a cell-edge user in the network. To do so, an interference cancelation scheme is devised to prevent the interference to the in-cell user from the cell-edge user. Then, we derive a suboptimal joint precoding based on the concept of signal-to-leakage plus noise ratio (SLNR) and present a power allocation method over the two clusters of antennas assuming that the second antenna clusters of the BSs have the same transmit power. Finally, the other similar transmission scheme is proposed to improve the performance of the cell-edge user. Results show that the proposed coordinated transmission schemes significantly increase the performance of the downlink cellular system.