Outage Analysis of AmBC-Enabled Vehicular Communications Under Mixed Nakagami-$m$ and Cascaded Nakagami-$m$ Fading Channels

Ambient backscatter communication (AmBC) is proposed as a prominent technology to support energy-efficient low power transmissions in 6G and beyond wireless networks. AmBC is capable of providing battery-free connectivity among large scale Internet-of-Things (IoT) devices. Also, it can satisfy the stringent delay and power saving requirements of intelligent transport systems (ITS) in seeking diverse vehicular applications. Motivated by these emerging trends, we consider an AmBC-assisted tag-reader-based vehicular scenario and carried out the outage analysis by deriving the exact expressions for the reader's outage probability (OP) considering tag being in reflective or non-reflective state over mixed Nakagami-m and double Nakagami-m fading environment. We also examine the asymptotic OP in the high signal-to-noise (SNR) regime, which is perfectly aligned with the exact OP values even at moderate SNRs. Further, this asymptotic analysis reveals some meaningful insights into the systems diversity order. Numerical and simulation studies are conducted to validate our mathematical framework.