Achieving High UAV Uplink Throughput by Using Beamforming on Board

Abstract

High-throughput unmanned aerial vehicle (UAV) communication may unleash the true potential of novel applications for aerial vehicles but also represents a threat for cellular networks due to the high levels of generated interference. In this article, we investigate how a beamforming system installed on board a UAV can be efficiently used to ensure high-throughput uplink UAV communications with minimum impact on the services provided to users on the ground. We study two potential benefits of beamforming, namely, spatial filtering of interference and load balancing, considering different beam switching methodologies. Our analysis is based on system-level simulations followed by a series of measurement campaigns in live Long-Term Evolution (LTE) networks. Our results show that using UAV-side beamforming has a great potential to increase uplink throughput of a UAV while mitigating interference. When beamforming is used, even up to twice as many UAVs may be served within a network compared with UAVs using omni-directional antennas, assuming a constant uplink throughput target. However, to fully exploit the potential of beamforming, a standardized solution ensuring alignment between network operators and UAV manufacturers is required.

3D beamforming and handover analysis for UAV networks

“…In this context, researchers mention that 5G is a good candidate as it supports beamforming and high throughput links, while being highly configurable [8]. On the other side, authors of [9] suggest to put highly directive antennas on the UAV. Another solution is proposed by the authors of [10].…”

A Centralized and Scalable Uplink Power Control Algorithm in Low SINR Scenarios

“…7 We thus believe that advanced techniques, e.g. directional antennas or beamforming [22], have to be further utilized. Moreover, some schedule algorithms, e.g.…”

Empirical Low-Altitude Air-to-Ground Spatial Channel Characterization for Cellular Networks Connectivity

“…using the existing cellular infrastructure to provide reliable command and control (C2) communications and high-throughput payload communications such as high-definition videos for UAV-user equipments (UEs), have attracted a surge of interest in both academia and industry [11], [12] in 5G and beyond communication systems. Although preliminary field investigations [13]- [15] have shown the potential of cellular networks in providing reliable C2 and high-throughput payload communications, there are still challenges that may lead to the system bottlenecks. For example, cellular BS antennas are usually targeted to serve ground users and hence down-tilted; UAV-UEs in the sky may cause severe interferences [16], [17] among them and to the ground UEs in both up-and downlinks, which limits the spectrum efficiency significantly.…”

“…Several investigations dealing with the interferences through power control, network coordination, resource allocation, beam usage, etc. to increase the system capacity and protect the ground UEs have been conducted [15], [18]- [21]. In order to properly design and optimize the proposed techniques, realistic channel models for the air-to-ground (A2G) propagation channels in different environments are essential.…”

“…However, the spatial characteristics of the low-altitude A2G channels are essential to evaluate or verify various solutions proposed, e.g. the massive multiple-input-multiple-output (mMIMO) or beamforming based techniques [15], [40], [41] with the potential to mitigate interferences and increase the network capacity.…”