When Channel Bonding is Beneficial for Opportunistic Spectrum Access Networks

TL;DR

This paper develops an analytical model to evaluate when channel bonding improves throughput in Opportunistic Spectrum Access networks, considering network size, channel availability, and physical constraints, and suggests adaptive bonding strategies.

Contribution

It introduces a novel analytical framework for assessing channel bonding benefits in OSA networks, accounting for dynamic primary user activity and physical layer limitations.

Findings

Channel bonding generally increases throughput in OSA networks.

Adaptive channel bonding based on network conditions enhances performance.

Physical layer constraints reduce theoretical throughput gains.

Abstract

Transmission over multiple frequency bands combined into one logical channel speeds up data transfer for wireless networks. On the other hand, the allocation of multiple channels to a single user decreases the probability of finding a free logical channel for new connections, which may result in a network-wide throughput loss. While this relationship has been studied experimentally, especially in the WLAN configuration, little is known on how to analytically model such phenomena. With the advent of Opportunistic Spectrum Access (OSA) networks, it is even more important to understand the circumstances in which it is beneficial to bond channels occupied by primary users with dynamic duty cycle patterns. In this paper we propose an analytical framework which allows the investigation of the average channel throughput at the medium access control layer for OSA networks with channel bonding enabled. We show that channel bonding is generally beneficial, though the extent of the benefits depend on the features of the OSA network, including OSA network size and the total number of channels available for bonding. In addition, we show that performance benefits can be realized by adaptively changing the number of bonded channels depending on network conditions. Finally, we evaluate channel bonding considering physical layer constraints, i.e. throughput reduction compared to the theoretical throughput of a single virtual channel due to a transmission power limit for any bonding size.