Joint 3D Codebook Design and Beam Training for UAV Millimeter-Wave Communications

Abstract

Jittering effects significantly degrade the performance of UAV communications especially in millimeterwave (mmWave) band. To investigate and mitigate the impacts of UAV jitter to mmWave communications, we firstly model UAV mmWave channel based on the geometric relationship between element antennas of the uniform planar arrays (UPAs) in receiver side and transmitter side, and we incorporate the jittering effects to our channel model through extracting the relationship between UAV attitude & position and angle of arrival (AoA) & angle of departure (AoD) of the UPAs. Then, based on the extracted relationship, we propose to utilize UAV navigation information to obtain a rough estimation of AoA and AoD, and we also analyze the impact of AoA and AoD estimation error to UAV beamforming.Finally, we propose a direction-constrained beam training scheme to refine the AoA/AoD estimation.Particularly, we construct a partially random sensing matrix to measure the channel within a narrow angle range that is centered at the aforementioned rough estimate of AoA/AoD. Numerical results show that our proposed UAV beam training scheme with navigation information is able to fast and accurately estimate the AoA/AoD fluctuation caused by UAV jitter.

Codebook Designs for Millimeter-Wave Communication Systems in Both Low- and High-Mobility: Achievements and Challenges

“…They have high flexibility compared to conventional BSs. Recently, UAVs have been widely adopted as aerial access points to provide communication services for Internet of Things (IoT) devices [97]. We distinguish two types of UAV communications: UAV-to-UAV communications [98] and UAV-to-ground communications [99].…”

“…The existing solutions for communication systems cannot be directly applied in UAV mmWave communications because of the increased complexity in moving and 3D UAV scenarios. In [97], for UAV-based IoT device data collection scenarios, a 3D codebook and related beam training mechanism are designed. The beam pattern of this codebook includes the azimuth and elevation angle domains.…”

A Unified 3D Beam Training and Tracking Procedure for Terahertz Communication

“…As can be seen, the received SNR of all schemes increases with the number of narrow beams. Our proposed narrow beams outperform the benchmark scheme in [13] and [23], where the scheme of using uniform real angles yields the worst performance. With the increase of the number of narrow beams, the gap between the average performance and the worst-case performance decreases.…”

“…Since the optimal beam pair follow the form of array response vector, a straightforward method to reach a desired solution is to traverse all beam pairs from the codebooks composed of array response vectors with different angles [13]. The codebook for the i th UPA contains N 2 narrow beams (i.e., codewords) with N azimuth angles times N elevation angles uniformly distributed in range Ω i (which is specified in (3)).…”

“…• Uniform Real Angles [13]: For the k th UPA, we extend the codebook in [13] to our considered coverage by setting N azimuth angles uniformly distributed in…”