CoMP in heterogeneous networks: Linear transceiver design using the minimum weighted geometric-MSE criterion

Coordinated multipoint transmission (CoMP) is considered for a heterogeneous network where different kinds of base stations (BSs) are located. We focus on linear transceiver design with the goal of maximizing the weighted sum rate in the downlink of a multiple-input multiple-output orthogonal frequency division multiple access (MIMO-OFDMA) system, where each subchannel is allocated to a single user. We address this in the context of minimizing the weighted geometric mean of the mean-square-errors (MSEs), i.e., weighted geometric-MSE minimization. The problem is non-convex as in multi-user case, thus, the problem of finding the global optimum is an intrinsically intractable, NP hard problem. We propose an algorithm which divides the main problem into several convex subproblems. The proposed algorithm is shown to provide computationally efficient suboptimal solutions.