Enabling multi-service radio access networks with Massive MIMO

在过去的十年中，移动通信网络已经从提供语音和基本信息服务的系统发展成为社会的一个组成部分，使语音和视频通信、互联网接入、银行、物流、导航和应急服务等一系列丰富的服务成为可能。拥有高性能数据中心设备的不断增长的客户群推动了对无线接入网络（RAN）容量的需求。为了满足这一需求，研发人员已经交付了几代无线接入技术，并在全球范围内推出，从2012年10月起，4G在英国实现了真正的移动宽带体验。最新表现形式5G将在2018-2019年完成标准化后在全球部署。与4G RAN相比，5G RAN的关键技术差异之一是原生使用有源天线系统，从而使有限频谱资源的基站的使用效率实现前所未有的阶梯形变化。有源天线系统（AAS，也称为大规模MIMO）受益于电路和电子技术的进步以及基带处理器的低成本计算能力，可以提供对组成蜂窝天线的多个天线元件的独立控制。这种更精细的控制水平使基站能够根据个别用户的情况对传输进行微调，并增强用户对传输的接收。对用户体验的净影响可以描述为对无限容量的感知，用户接收到其服务所需的资源，从而增强了服务和应用程序的响应性。除了令人印象深刻的AAS研究和实施的第一步之外，面临的挑战是能够解决在延迟、可靠性、覆盖和速度方面具有不同连接需求的新兴应用程序和服务。许多这样的新用例，包括各种机器对网络通信、工业自动化和运输、紧急和关键服务，将必须使用相同的网络基础设施，包括基站和天线系统提供。由于研究和学术界的主要推动力一直是容量和能源效率，迄今为止还没有一种技术可以利用AAS的功能来实现这种多服务用例。“网络切片”的概念也没有解决这一研究挑战，因为它没有考虑数字信号处理和AAS的架构。该研究项目将探索并提供AAS中的多业务处理能力，能够平衡可靠性、覆盖范围和整体网络容量。具体来说，我们将研究这种多服务RAN通过单一物理基础设施可持续地提供混合类型服务的可行性和性能界限。我们将确定具有AAS的RAN物理层可实现的可靠性和容量之间的基本权衡因素，并设计处理方法，以有效地支持用户差异化，同时保持网络容量。我们将与标准化机构和行业内的行业和学术利益相关者合作，推动已确定的解决方案走向实际实现，并推动技术的进一步发展。

Mobile communication networks have evolved over past decade from systems providing voice and basic messaging service to an integral part of society, enabling a rich set of services from voice and video communications, internet access, banking, logistics, navigation and emergency services. A growing customer base with highly capable data centric devices has fuelled a demand for capacity in radio access networks (RAN). To meet this demand, research and development has delivered generations of radio access technologies, rolled out globally, with 4G enabling true mobile broadband experience in the UK from October 2012. The latest manifestation, 5G, being deployed globally following the completion of standardisation in 2018-2019. One of the key technological differences in 5G RAN compared to 4G RAN is native use of active antenna systems to deliver an unprecedented step change in the efficiency of use by base stations of limited spectrum resources. Active antenna systems (AAS, also known as Massive MIMO) benefit from progress in circuit and electronics technology and low cost computing power in baseband processors to provide independent control over the multiple antenna elements comprising a cellular antenna. Such finer level of control enables basestations to fine-tune transmissions to individual user conditions and to enhance the reception of transmissions by users. The net effect on user experience can be described as a perception of infinite capacity, with a user receiving the resources that their service requires and consequent enhanced responsiveness of services and applications.The challenge beyond the impressive first steps in AAS research and implementation is to be able to address emerging applications and services carrying different connectivity requirements in terms of latency, reliability, coverage and speed. Many of such new use cases including various machine-to-network communications, industrial automation and transportation, emergency and critical services will have to be provided using the same network infrastructure, including the base stations and antenna systems. No technology exploiting capabilities of AAS for such multi-service use cases exists to date since the primary driver in research and academia has been capacity and energy efficiency. A concept of 'network slicing' does not address this research challenge either since it does not consider digital signal processing and architectures of AAS.This research programme will explore and deliver a multi-service processing capability in AAS, capable of balancing reliability, coverage and overall network capacity. Specifically, we will investigate the feasibility and performance bounds of such multiservice RAN in delivering mixed types of services sustainably through a single physical infrastructure. We will identify fundamental trade-off factors between reliability and capacity achievable on physical layer of RAN with AAS, and design processing methods to effectively support user differentiation while maintaining network capacity. We will work with industry and academic stakeholders within standardisation bodies and industry to drive the identified solutions to practical realisation and shape further evolution of technology.