Noncausal Zero-Forcing precoding subject to individual channel power constraints

This paper investigates Zero Forcing (ZF) precoding in MIMO FB channels subject to individual channel power constraints. It shows that the optimal ZF precoder is non-causal in general and presents a general formulation for the design of optimal noncausal ZF precoder subject to individual channel power constraints. A convex optimization based method is derived from the formulation to design optimal noncausal precoder. Numerical example demonstrates the effectiveness of the design method and the advantage of the designed optimal noncausal ZF precoder.