A survey of 5G millimeter wave, massive multiple‐input multiple‐output, and vehicle‐to‐vehicle channel measurements and models

Abstract

There is no doubt that the world evolves nowadays in the digital communications era. This opens the horizon to research and investment in new promising technologies like 5G and beyond cellular networks that are able to increase the subscribers' data rates in all communication systems. The aim of 5G and beyond cellular networks is to provide anywhere and anytime connectivity. By combining the enormous available bandwidth in millimeter wave (mmWave) frequencies with high multiplexing gains achieved by large antenna arrays in multiple-input multiple-output (MIMO) systems, these technologies can significantly improve network throughput, increase network power, boost energy and spectral efficiency, and enhance network coverage. Furthermore, ultrareliable vehicular communication and high capacity would be essential features of communication networks beyond 5G. Fortunately, when vehicles are moving on the road and communicating with each other, the vehicular communication issue becomes more challenging. Among the several new technologies expected to play significant roles in the 5G and beyond systems, this paper focused on summarizing the state-of-the-art mmWave, vehicle-to-vehicle (V2V), and massive MIMO measurements and models. We introduce a detailed overview of each of the three technologies individually. Besides, novel taxonomies for the 5G channel measurements, objectives, and model types are provided. We expect that mmWave-based massive MIMO technology enables real-time channel estimation and ultra-precise beamforming, and thus enables better service coverage. Finally, challenges and future research directions for 5G channel measurements and models are presented.

On the spectral efficiency of cell‐free massive MIMO system in irregular 5G mobile networks

“…Over the last decade, tremendous literature has been emerged on the CF massive MIMO paradigm in the 5G and beyond. 13,[26][27][28] The CF massive MIMO technology is particularly characterized by the ultra-dense deployment of APs that are supposed to cover certain areas in the network. Each AP can communicate with users and network core using single or multiple antennas.…”

Optimized planar printed UCA configurations for OAM waves and the associated OAM mode content at the receiver

“…Electromagnetic (EM) waves characterized by helical wavefronts, and thus carrying the orbital angular momentum (OAM), have recently attained increased attention. Despite some controversial discussions, OAM waves are, besides other applications, seen as enablers of further increase in a hybrid optical/wireless communication system capacity and transmission data rates 1–4 . Along with other component and system design approaches, 5–10 the use of OAM waves could help fulfill the key requirements of 5G and beyond 5G networks.…”

“…Despite some controversial discussions, OAM waves are, besides other applications, seen as enablers of further increase in a hybrid optical/wireless communication system capacity and transmission data rates. [1][2][3][4] Along with other component and system design approaches, [5][6][7][8][9][10] the use of OAM waves could help fulfill the key requirements of 5G and beyond 5G networks. In 5G networks, an increase in system capacity by two to three orders of magnitude is demanded to support the massive growth in data transmission, enabling the enhanced mobile broadband communications and human-to-machine and machine-to-machine communications, along with ultra-reliable and low-latency communications.…”

An Effective Kalman Based Hybrid Beamforming for Millimeter Wave Massive MIMO System by Using 2D Overlapped Partially Connected Sub-Array Structure

“…Again, this results in interference, which can be mitigated by using beamforming antennas rather than standard antennas. M-MIMO offers enhanced throughput, low-power, low-cost components, and spectral capacity efficiency [6].…”