Resource allocation for statistical QoS guarantees in MIMO cellular networks

Ozgur Ercetin,Ozgur Gurbuz,Seyed Vahid Azhari,Mehmet Ozerk Memis

doi:10.1186/s13638-015-0446-7

Abstract

This work considers the performance of the downlink channel of MIMO cellular networks serving multiple users with different statistical QoS requirements. The paper proposes resource allocation algorithms that aim to optimize the system performance over the sum of the optimal user utility functions by employing the effective capacity theory. Proportionally fair resource allocation among the users is performed via two different approaches and solutions, namely, the Frame Allocation Algorithm (FAA), which involves dynamic time allocation for transmit beamforming, and the Power Allocation Algorithm (PAA), which provides optimal power control for space division multiple access. In FAA, each user is assigned a distinct slot of optimal length, based on the instantaneous channel conditions of the active users in each frame; while in PAA, resource allocation is performed via power assignment by taking into account the long-term averages of the channel conditions across all users. The efficacy of the proposed algorithms are demonstrated via numerical experiments considering realistic channel models and various QoS settings.

Highlights

Last-mile connections to end-users are becoming predominantly wireless
We focus on downlink multi-user quality of service (QoS) provisioning via dynamic resource allocation in MIMO cellular networks considering two scenarios considering whether channel state information (CSI) is fully available or not
Effective capacity of MIMO links are calculated under two different resource allocation regimes, where either time or fixed power resources are allocated among users

Summary

Introduction

Last-mile connections to end-users are becoming predominantly wireless. In order to deliver the same performance to end-users as if they are connected to a wired network, new techniques to maximize the throughput in all-wireless networks must be developed. We focus on downlink multi-user QoS provisioning via dynamic resource allocation in MIMO cellular networks considering two scenarios considering whether CSI is fully available or not For these scenarios, we propose effective capacity-based resource allocation schemes, considering MIMO users receiving delay-sensitive data streams from a base station (BS) over time-varying wireless channels. In [38], the authors propose a power allocation scheme that optimally allocates average transmission power to different MIMO streams, such that joint power and spectrum efficiency is achieved, while the statistical QoS requirement captured as the constraint on the link’s effective capacity is satisfied at the same time. We propose a time allocation algorithm (FAA) for the case when the instantaneous CSI is available, and a power allocation algorithm (PAA), when only the average CSI is available at the BS

Effective capacity theory

System model

Frame allocation algorithm for time division multiple access

Channel model

Power allocation algorithm for space division multiple access

Effective capacity formulation

Performance analysis

Form ψ based on the set ECl

Findings

Conclusions