This paper presents a new virtualization method for the downlink of a multi-cell multiple-input multiple-output (MIMO) network, to achieve service isolation among multiple Service Providers (SPs) that share the base station resources of an Infrastructure Provider (InP). Each SP designs a virtual precoder for its users in each cell, as its service demand to the InP, without the need to be aware of the existence of the other SPs or to know the channel state information (CSI) outside the cell. The InP performs network virtualization to meet the SPs' service demands while managing both the inter-SP and inter-cell interference. We consider coordinated multi-cell precoding at the InP and formulate an optimization problem to minimize a weighted sum of signal leakage and precoding deviation, with per-cell transmit power constraints. We propose a fully distributed semi-closed-form solution at each cell, without any CSI exchange across cells. We further propose a low-complexity scheme to allocate the virtual transmit power, for the InP to regulate between interference elimination and virtual demand maximization. Simulation results demonstrate that our precoding solution for network virtualization substantially outperforms the traditional spectrum isolation alternative. It can approach the performance of fully cooperative precoding when the number of antennas is large.

翻译：本文为多细胞多投入多产出网络的下行连接提供了一个新的虚拟化方法,以在共享基础设施提供者(InP)基站资源的多个服务提供者之间实现服务隔离。每个SP为每个单元的用户设计了一个虚拟预码器,作为它向InP的服务需求,而不必了解其他SP的存在或了解细胞外的频道状态信息。InP运行网络虚拟化以满足SP的服务需求,同时管理跨SP和跨细胞干扰。我们考虑在InP进行协调的多细胞预编码,并制定一个优化问题,以最大限度地减少信号泄漏和预编码偏差的加权总和,而每个单元传输电力限制。我们提议在每个单元完全分发半封闭式解决方案,而无需了解其他SP的存在或了解细胞间的任何CSI交换。我们进一步提议一个低兼容性计划,分配虚拟传输能力,以便InP管理干扰消除和虚拟需求最大化之间的调控。我们考虑在InP中采用协调的多细胞预先编码,并制定一个优化的问题,以最大限度地减少信号泄漏和预先编码偏差,每个单元传输能力限制。我们提出的半封闭式的系统前的方法在虚拟化前完全可以将光谱路路路路系转换成一个大的节路系。