Successive Zero-Forcing DPC With Per-Antenna Power Constraint: Optimal and Suboptimal Designs
This paper considers the pre-coder designs for Successive Zero-Forcing Dirty Paper Coding (SZF-DPC), a suboptimal transmission technique for MIMO Broadcast Channels (MIMO BCs). Existing pre-coder designs for SZF-DPC often consider a sum power constraint. In this paper, the authors address the pre-coder design for SZF-DPC with Per-Antenna Power Constraints (PAPCs), which has not been well studied. First, they formulate the pre-coder design as a rank-constrained optimization problem, which is generally difficult to handle. To solve this problem, they follow a relaxation approach, and prove that the optimal solution of the relaxed problem is also optimal for the original problem.