Distributed coordinated precoding for MIMO cellular network virtualization

TL;DR

This paper introduces a distributed virtualization method for multi-cell MIMO networks that enables service isolation among multiple providers without requiring inter-cell CSI exchange, improving performance over traditional spectrum isolation.

Contribution

It proposes a novel distributed precoding scheme for network virtualization in multi-cell MIMO systems, eliminating the need for inter-cell CSI sharing and optimizing interference management.

Findings

Outperforms traditional spectrum isolation methods.

Approaches the performance of fully cooperative precoding with many antennas.

Provides a low-complexity power allocation scheme.

Abstract

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.