Coordinated precoding in multi-cell scenarios with interference CSI only

This paper considers coordinated precoding design in multi-cell scenarios where transmitters and receivers are both equipped with multiple antennas. To suppress the co-channel interference, much channel state information (CSI) should be sent back to the transmitters. Most previous work in the area has assumed that transmitters have common knowledge of both data symbols of all users and full or local CSI. Herein, we propose coordinated precoding scheme with interference CSI only. Note that interference CSI denotes the channel state information from the transmitter to the interference user particularly. "Zero- Forcing" (ZF) method can be easily adopted to minimize the cochannel interference. However, coordinated ZF precoding imposes a condition that each BS should have more antennas than receive antennas combined by all users. Therefore, a coordinated precoding scheme is presented by minimizing leakage-plus-noise (MLN) which is similar to maximizing signalto- leakage-plus-noise ratio (SLNR) criterion. Simulation results show that the proposed precoding scheme endures an acceptable performance loss compared to traditional schemes while much feedback overload is reduced.