Optimization of MIMO Device-to-Device Networks via Matrix Fractional Programming: A Minorization-Maximization Approach

TL;DR

This paper introduces FPLinQ, a novel optimization method based on matrix fractional programming and minorization-maximization, to improve interference management and link scheduling in MIMO device-to-device networks.

Contribution

It develops a new optimization framework called matrix fractional programming and demonstrates its application to D2D networks, allowing multiple data streams and arbitrary device associations.

Findings

FPLinQ outperforms existing scheduling methods like FlashLinQ and ITLinQ+.

The approach enables multiple antennas and data streams per link.

Numerical results show significant performance improvements.

Abstract

Interference management is a fundamental issue in device-to-device (D2D) communications whenever the transmitter-and-receiver pairs are located in close proximity and frequencies are fully reused, so active links may severely interfere with each other. This paper devises an optimization strategy named FPLinQ to coordinate the link scheduling decisions among the interfering links, along with power control and beamforming. The key enabler is a novel optimization method called matrix fractional programming (FP) that generalizes previous scalar and vector forms of FP in allowing multiple data streams per link. From a theoretical perspective, this paper provides a deeper understanding of FP by showing a connection to the minorization-maximization (MM) algorithm. From an application perspective, this paper shows that as compared to the existing methods for coordinating scheduling in the D2D network, such as FlashLinQ, ITLinQ, and ITLinQ+, the proposed FPLinQ approach is more general in allowing multiple antennas at both the transmitters and the receivers, and further in allowing arbitrary and multiple possible associations between the devices via matching. Numerical results show that FPLinQ significantly outperforms the previous state-of-the-art in a typical D2D communication environment.