Impacts of Hardware Impairments on Mutualistic Cooperative Ambient Backscatter Communications

TL;DR

This paper investigates how hardware impairments affect the performance and mutualistic relationship in ambient backscatter communications, showing that despite degradation, the primary and AmBC links maintain their mutual benefits.

Contribution

It provides the first theoretical analysis of hardware impairments' effects on mutualistic cooperative AmBC networks, deriving closed-form rate expressions and validating them through simulations.

Findings

Hardware impairments degrade link rates but do not break mutualism.

The primary link's rate remains higher with AmBC than without.

Closed-form expressions accurately predict system performance.

Abstract

In mutualistic cooperative ambient backscatter communications (AmBC), Internet-of-Things (IoT) device sends its information to a desired receiver by modulating and backscattering the primary signal, while providing beneficial multipath diversity to the primary receiver in return, thus forming a mutualism relationship between the AmBC and primary links. We note that the hardware impairments (HIs), which are unavoidable in practical systems and may significantly affect the transmission rates of the primary and AmBC links and their mutualism relationships, have been largely ignored in the study of mutualistic cooperative AmBC networks. In this paper, we consider a mutualistic cooperative AmBC network under HIs, and study the impacts of HIs on the achievable rates of the primary link and the AmBC link. In particular, we theoretically prove that although HIs degrades the rate of each link, the mutualism relationship between the AmBC and primary links is maintained, i.e., the rate of the primary link in the mutualistic cooperative AmBC network is still higher than that without the AmBC link. The closed-form rate expressions of both the AmBC and primary links are derived. Computer simulations are provided to validate our theoretical analysis.