Capacity analysis and optimal power allocation for coordinated transmission in MIMO-OFDM systems

Coordinated transmission in multicell coordination networks has attracted much attentions in recent years. In the paper, we investigate one open problem in the above area, which is concerned with how to solve the closed-form optimal power allocation scheme of coordinated transmission in downlink orthogonal frequencydivision multiplexing (OFDM) systems with multiple antenna configurations and individual power constraints. A frequency-selective fading multiple-input multiple-output (MIMO) channel is considered. We derive the closed-form solutions of sum-rate capacity and optimal power allocations for coordinated transmission under the diversity case and the multiplexing case by solving the constrained optimization problems. Numerical simulations are performed to verify the derived theoretical conclusions by means of comparing the proposed optimal power allocation (OPA) scheme with the other two typical power allocation schemes. One is the power allocation scheme combining traditional water-filling with equal power (WS-EF PA). The other is equal power allocation (EPA) scheme.