On the Effective Capacity of Two-Hop Communication Systems

TL;DR

This paper analyzes the maximum sustainable data rates in two-hop relay systems under buffer constraints and QoS requirements, highlighting how these limitations affect overall throughput.

Contribution

It provides a novel characterization of effective capacity in two-hop systems with buffer constraints and perfect channel information.

Findings

Buffer constraints significantly reduce maximum throughput.

Effective capacity depends on QoS parameters and channel conditions.

The analysis offers insights for designing reliable two-hop communication links.

Abstract

In this paper, two-hop communication between a source and a destination with the aid of an intermediate relay node is considered. Both the source and intermediate relay node are assumed to operate under statistical quality of service (QoS) constraints imposed as limitations on the buffer overflow probabilities. It is further assumed that the nodes send the information at fixed power levels and have perfect channel side information. In this scenario, the maximum constant arrival rates that can be supported by this two-hop link are characterized by finding the effective capacity. Through this analysis, the impact upon the throughput of having buffer constraints at the source and intermediate-hop nodes is identified.