A High-Level Comparison of Recent Technologies for Massive MIMO Architectures

TL;DR

This paper compares recent massive MIMO architectures, including emerging intelligent surface-assisted and Rotman lens-based designs, analyzing their efficiency, quality trade-offs, and power efficiency in cellular networks.

Contribution

It introduces a comprehensive comparison framework for various mMIMO architectures considering hardware imperfections and a universal precoding algorithm.

Findings

Reflect/transmit array architectures offer the best trade-off.

Power efficiency ranking is frequency-independent.

Emerging architectures outperform conventional approaches in certain metrics.

Abstract

Since the introduction of massive MIMO (mMIMO), the design of a transceiver with feasible complexity has been a challenging problem. Initially, it was believed that the main issue in this respect is the overall RF-cost. However, as mMIMO is becoming more and more a key technology for future wireless networks, it is realized, that the RF-cost is only one of many implementational challenges and design trade-offs. In this paper, we present, analyze and compare various novel mMIMO architectures, considering recent emerging technologies such as intelligent surface-assisted and Rotman lens based architectures. These are compared to the conventional fully digital (FD) and hybrid analog-digital beamforming (HADB) approaches. To enable a fair comparison, we account for various hardware imperfections and losses and utilize a novel, universal algorithm for signal precoding. Based on our thorough investigations, we draw a generic efficiency to quality trade-off for various mMIMO architectures. We find that in a typical cellular communication setting the reflect/transmit array based architectures sketch the best overall trade-off. Further, we show that in a qualitative ranking the power efficiency of the considered architectures is independent of the frequency range.