In developing technologies for deploying massive MIMO systems, we are exploiting the systems’ decorrelation property to avoid unnecessary pre-coder computations, thereby reducing scheduler overhead.
In our work with millimeter wave technologies, we are developing solutions using beam tracking technology that do not require explicit channel measurement. We are also creating a novel design framework for MU-MIMO scheduling in millimeter-wave networks that considers hybrid beamforming (analog plus digital precoding) at the transmitter and receiver nodes. We use transmit and receive analog precoding to reduce the CSI feedback overhead.
Dual connectivity (DC) is a feature that targets emerging practical HetNet deployments that will consist of non-ideal (higher latency) connections between transmission nodes. It has been recently introduced to the LTE-Advanced standard. DC allows for a user to be simultaneously served by a macro node as well as one other (typically micro or pico) node and requires coarser level coordination among serving nodes. For such a DC-enabled HetNet, we comprehensively analyze the problem of determining an optimal user association and then develop efficient solutions.