Enabling Ultra-Dense, Open-RAN, Vehicular Networks with Non-Linear MIMO Processing

TL;DR

This paper introduces a non-linear MIMO processing method for ultra-dense vehicular networks, significantly increasing device connectivity and reducing infrastructure costs in open-RAN deployments.

Contribution

It proposes a novel Massively Parallelizable Non-linear (MPNL) MIMO processing technique that outperforms linear methods in dense vehicular networks, enabling higher connectivity with fewer antennas.

Findings

Over 300% increase in concurrent single-antenna vehicle connections

Significant reduction in required antennas without throughput loss

Enabling simpler, more dense radio unit deployments

Abstract

Future autonomous transportation systems necessitate network infrastructure capable of accommodating massive vehicular connectivity, despite the scarce availability of frequency resources. Current approaches for achieving such required high spectral efficiency, rely on the utilization of Multiple-Input, Multiple-Output (MIMO) technology. However, conventional MIMO processing approaches, based on linear processing principles, leave much of the system's capacity heavily unexploited. They typically require a large number of power-consuming antennas and RF-chains to support a substantially smaller number of concurrently connected devices, even when the devices are transmitting at low rates. This translates to inflated operational costs that become substantial, particularly in ultra-dense, metropolitan-scale deployments. Therefore, the question is how to efficiently harness this unexploited MIMO capacity and fully leverage the available RF infrastructure to maximize device connectivity. Addressing this challenge, this work proposes an Open Radio Access Network (Open-RAN) deployment, with Massively Parallelizable Non-linear (MPNL) MIMO processing for densely deployed, and power-efficient vehicular networks. For the first time, we quantify the substantial gains of MPNL in achieving massive vehicular connectivity with significantly reduced utilized antennas, compared to conventional linear approaches, and without any throughput loss. We find that an Open-RAN-based realization exploiting the MPNL advancements can yield an increase of over 300% in terms of concurrently transmitting single-antenna vehicles in urban mobility settings and for various Vehicle-to-Infrastructure (V2I) and Network (V2N) use cases. In this context, we discuss how implementing MPNL allows for simpler and more densely deployed radio units, paving the way for fully autonomous and sustainable transportation systems.