CNN Autoencoder Resizer: A Power-Efficient LoS/NLoS Detector in MIMO-enabled UAV Networks
Azim Akhtarshenas, Navid Ayoobi, David Lopez-Perez, Ramin Toosi, Matin Amoozadeh
TL;DR
The paper addresses LoS/NLoS identification in UAV-enabled wireless networks, a problem intensified by power constraints on sensing hardware. It introduces the CNN Autoencoder Resizer (CAR), a dual-autoencoder framework with a shared latent vector that maps low-dimensional channel outputs to high-dimensional representations, serving as a preprocessing step to boost discrimination without increasing power consumption. CAR achieves a substantial accuracy gain, elevating LoS/NLoS detection from $66\%$ to $86\%$ while maintaining power efficiency, and is designed to work with smaller antenna arrays by transferring learned high-resolution representations from larger arrays. The approach offers a practical, scalable enhancement for UAV-based NTN deployments, enabling more reliable connectivity with reduced hardware burden.
Abstract
Optimizing the design, performance, and resource efficiency of wireless networks (WNs) necessitates the ability to discern Line of Sight (LoS) and Non-Line of Sight (NLoS) scenarios across diverse applications and environments. Unmanned Aerial Vehicles (UAVs) exhibit significant potential in this regard due to their rapid mobility, aerial capabilities, and payload characteristics. Particularly, UAVs can serve as vital non-terrestrial base stations (NTBS) in the event of terrestrial base station (TBS) failures or downtime. In this paper, we propose CNN autoencoder resizer (CAR) as a framework that improves the accuracy of LoS/NLoS detection without demanding extra power consumption. Our proposed method increases the mean accuracy of detecting LoS/NLoS signals from 66% to 86%, while maintaining consistent power consumption levels. In addition, the resolution provided by CAR shows that it can be employed as a preprocessing tool in other methods to enhance the quality of signals.
