Beam tracking in phased array antenna based on the trajectory classification

Abstract

One of the major new concepts in 5G cellular communications is a shift in the way services are delivered to users. In the new 5G protocol, individual users are recognized and tracked through beams, which are targeted and specific to individual users. The millimeter-wave (mmWave) communications impose a directionality which results in a significant challenge in serving mobile terminals and unmanned aerial vehicles. This challenge can be relieved in mmWave systems using analog beamforming. Based on the identification of the patterns in the reference signal received power (RSRP) measurements, some classifications are employed. Some trajectories are defined for different users in Hallways. Therefore, the angle of arrival (AoA) would be the same for the users following the same trajectory. The users based on the received RSRP values are clustered by K-means and I-Kmeans algorithms. To this end, our algorithms to find the beamforming coefficient are employed for only one user in each cluster and the complexity of the algorithms can be lower. The proposed algorithms are spatial frequency-based beam tracking and angular domain beam tracking algorithms. Simulation results show that tracking the sine function of AoA achieves better performance compared to tracking the AoA. Moreover, the optimal number of clusters is obtained by using the Elbow method. INTRODUCTIONThe effects of 5G are visible on the Internet of Things (IoT), Augmented Reality (AR), unmanned aerial vehicles (UAV), industrial automation (IA), smart homes, smart cities, time-critical applications in telemedicine and telesurgery and so forth. 1 5G includes some different areas such as enhanced mobile broadband (eMBB), ultra-reliable and low-latency communications (URLLC), and massive machine type communications (mMTC). 2,3 Due to the direct impact on the public, this article focuses on the human-centric enhanced mobile broadband activity. 4 When new applications emerge, new requirements for greater broadband data are required and the demand for faster data is a growing option. 5 This article investigates the analysis of 5G millimeter-wave (mmWave) services in hotspots and for indoor-area coverage which will result in high user density and high capacity.Compared to sub-6-GHz communication links, the path loss at mmWave frequencies is greater. To alleviate this issue, phased-array techniques alongside Line-of-Sight (LoS) and Non-Line-of-Sight (NLoS) communication with an array antenna gain can be employed. In Reference 6, the performance of the coordinated multi-point (CoMP) based mmWave communication is analyzed. The aforementioned work considers the effect of the LoS component which is essential in mmWave communications due to the high path-loss properties of high frequency mmWave channels. Moreover, a