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Register a new userCluster-based Characterization and Modeling for UAV Air-to-Ground Time-Varying Channels
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Added by
Zhuangzhuang Cui
Publication date
2021
fields
Electronic Engineering
and research's language is
English
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With the deep integration between the unmanned aerial vehicle (UAV) and wireless communication, UAV-based air-to-ground (AG) propagation channels need more detailed descriptions and accurate models. In this paper, we aim to perform cluster-based characterization and modeling for AG channels. To our best knowledge, this is the first study that concentrates on the clustering and tracking of multipath components (MPCs) for time-varying AG channels. Based on measurement data at 6.5 GHz with 500 MHz of bandwidth, we first estimate potential MPCs utilizing the space-alternating generalized expectation-maximization (SAGE) algorithm. Then, we cluster the extracted MPCs considering their static and dynamic characteristics by employing K-Power-Means (KPM) algorithm under multipath component distance (MCD) measure. For characterizing time-variant clusters, we exploit a clustering-based tracking (CBT) method, which efficiently quantifies the survival lengths of clusters. Ultimately, we establish a cluster-based channel model, and validations illustrate the accuracy of the proposed model. This work not only promotes a better understanding of AG propagation channels but also provides a general cluster-based AG channel model with certain extensibility.
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To provide high data rate aerial links for 5G and beyond wireless networks, the integration of free-space optical (FSO) communications and aerial platforms has been recently suggested as a practical solution. To fully reap the benefit of aerial-based FSO systems, in this paper, an analytical channel model for a long-range ground-to-air FSO link under the assumption of plane wave optical beam profile at the receiver is derived. Particularly, the model includes the combined effects of transmitter divergence angle, random wobbling of the receiver, jitter due to beam wander, attenuation loss, and atmospheric turbulence. Furthermore, a closed-form expression for the outage probability of the considered link is derived which makes it possible to evaluate the performance of such systems. Numerical results are then provided to corroborate the accuracy of the proposed analytical expressions and to prove the superiority of the proposed channel model over the previous models in long-range aerial FSO links.
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