Distributed Opportunistic Scheduling for MIMO Ad-Hoc Networks

TL;DR

This paper introduces distributed opportunistic scheduling protocols for MIMO ad-hoc networks that improve throughput by exploiting spatial multiplexing and diversity with minimal feedback, using threshold policies based on optimal stopping theory.

Contribution

The paper presents novel distributed scheduling protocols for MIMO ad-hoc networks that optimize throughput by leveraging spatial channels and threshold-based decision policies.

Findings

Protocols significantly improve network throughput.

Exploiting spatial multiplexing enhances data transmission capacity.

Threshold policies effectively balance feedback and performance.

Abstract

Distributed opportunistic scheduling (DOS) protocols are proposed for multiple-input multiple-output (MIMO) ad-hoc networks with contention-based medium access. The proposed scheduling protocols distinguish themselves from other existing works by their explicit design for system throughput improvement through exploiting spatial multiplexing and diversity in a {\em distributed} manner. As a result, multiple links can be scheduled to simultaneously transmit over the spatial channels formed by transmit/receiver antennas. Taking into account the tradeoff between feedback requirements and system throughput, we propose and compare protocols with different levels of feedback information. Furthermore, in contrast to the conventional random access protocols that ignore the physical channel conditions of contending links, the proposed protocols implement a pure threshold policy derived from optimal stopping theory, i.e. only links with threshold-exceeding channel conditions are allowed for data transmission. Simulation results confirm that the proposed protocols can achieve impressive throughput performance by exploiting spatial multiplexing and diversity.