Decentralized Multi-Antenna Architectures with Unitary Constraints

TL;DR

This paper explores decentralized multi-antenna base station architectures with unitary constraints, aiming to reduce processing complexity and energy consumption while analyzing the trade-offs with centralized systems.

Contribution

It introduces a unitary-restricted decentralized processing framework within the WAX model and proposes a method to minimize performance loss compared to centralized processing.

Findings

Energy-efficient implementations feasible with some performance trade-off

Proposed method reduces the performance gap with centralized systems

Characterizes the information-lossless trade-off in decentralized architectures

Abstract

The increase in the number of base station (BS) antennas calls for efficient solutions to deal with the increased interconnection bandwidth and processing complexity of traditional centralized approaches. Decentralized approaches are thus gaining momentum, since they achieve important reductions in data/processing volume by preprocessing the received signals before forwarding them to a central node. The WAX framework offers a general description of decentralized architectures with arbitrary interplay between interconnection bandwidth and decentralized processing complexity, but the applicability of this framework has only been studied assuming unrestricted baseband processing. We consider an adaptation of the WAX framework where the decentralized processing has unitary restriction, which allows for energy-efficient implementations based on reconfigurable impedance networks at the cost of some performance loss. Moreover, we propose an effective method to minimize the performance gap with respect to centralized processing. The previous method gives a first step towards characterizing the information-lossless trade-off between interconnection bandwidth and processing complexity in decentralized architectures with unitary constraints.