An Energy-Based Comparison of Long-Hop and Short-Hop Routing in MIMO Networks

TL;DR

This paper compares energy efficiency of long-hop versus short-hop routing in MIMO networks, revealing conditions under which each strategy is more energy-efficient based on network parameters and outage constraints.

Contribution

It provides a comprehensive analysis of energy consumption for different routing strategies in MIMO networks considering various network configurations and outage requirements.

Findings

Short-hop routing is more energy-efficient for large number of hops or high success probability.

Long-hop routing consumes less energy under same delay constraints as success probability approaches one.

Short-hop advantage increases with more transmit antennas under strict outage constraints.

Abstract

This paper considers the problem of selecting either routes that consist of long hops or routes that consist of short hops in a network of multiple-antenna nodes, where each transmitting node employs spatial multiplexing. This distance-dependent route selection problem is approached from the viewpoint of energy efficiency, where a route is selected with the objective of minimizing the transmission energy consumed while satisfying a target outage criterion at the final destination. Deterministic line networks and two-dimensional random networks are considered. It is shown that when 1) the number of hops traversed between the source and destination grows large or 2) when the target success probability approaches one or 3) when the number of transmit and/or receive antennas grows large, short-hop routing requires less energy than long-hop routing. It is also shown that if both routing strategies are subject to the same delay constraint, long-hop routing requires less energy than short-hop routing as the target success probability approaches one. In addition, numerical analysis indicates that given loose outage constraints, only a small number of transmit antennas are needed for short-hop routing to have its maximum advantage over long-hop routing, while given stringent outage constraints, the advantage of short-hop over long-hop routing always increases with additional transmit antennas.