The use of Millimeter-wave (mmWave) spectrum in cellular communications has recently attracted growing interest to support the expected massive increase in traffic demands. However, the high path-loss at mmWave frequencies poses severe challenges. In this paper, we analyze the potential coverage gains of using unmanned aerial vehicles (UAVs), as hovering relays, in integrated access and backhaul (IAB) mmWave cellular scenarios. Specifically, we utilize the WinProp software package, which employs ray tracing methodology, to study the propagation characteristics of outdoor mmWave channels at 30 and 60 GHz frequency bands in a Manhattan-like environment. In doing so, we propose the implementation of amplify-and-forward (AF) and decode-and-forward (DF) relaying mechanisms in the WinProp software. We show how the 3D deployment of UAVs can be defined based on the coverage ray tracing maps at access and backhaul links. Furthermore, we propose an adaptive UAV transmission power for the AF relaying. We demonstrate, with the aid of ray tracing simulations, the performance gains of the proposed relaying modes in terms of downlink coverage, and the received signal to interference and noise ratio (SINR).
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Physical Layer Performance of a Cooperative Amplify and Forward Scheme for MIMO WLANs
This paper proposes a novel cooperative amplify and forward (CAF) architecture for MIMO WLANs to improve their coverages and transmission rates, without requiring any modifications in the IEEE 802.11 standards at the clients. System models are used for analyzing physical layer of CAF networks, and compared with conventional amplify-and-forward (AF) and decode-and-forward (DF) networks. Numerical results demonstrate that CAF network clearly outperforms conventional 802.11 networks, AF and DF networks in terms of coverage and throughput.
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- Award ID(s):
- 1738093
- PAR ID:
- 10095307
- Date Published:
- Journal Name:
- IEEE Transactions on Vehicular Technology
- ISSN:
- 0018-9545
- Page Range / eLocation ID:
- 1 to 1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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