# From 5G to 6G--Challenges, Technologies, and Applications
## 4 Current Research
### Numerical Discussion
\begin{table}
\begin{tabular}{c c} \hline \hline
**Category** & **Paper** & **Summary** \\ \hline Waveform & [118] & Discussed the best waveform design and efficient sensing techniques in 6G cellular joint communication and sensing systems. \\  & [119] & Studied terahertz frequencies through extensive ray tracing simulations to generate stochastic and cluster-based channel models. \\  & [120] & Investigated receivers’ design for 6G communication beyond 100 GHz with a focus on power consumption and performance tradeoffs. \\  & [121] & Analyzed phase noise for B5G systems and proposed a compensation algorithm for it in frequency multiplexing receivers. \\ \hline Antennas & [122] & Presented the operating principles and design of the different quasi-optical beamformers in future multi-beam antennas. \\  & [123] & Provided the analysis and comparison of different circuit-type multiple beamforming networks for antenna arrays in 6G networks. \\  & [124] & Proposed a beyond 5G spatially multiplexed fronthaul network with dynamic beamforming and steering with different technologies. \\  & [125] & Studied beam management in B5G systems with the integration of orientation information coming from inertial measurement units. \\ \hline AI & [126] & Gave a detailed look at ML techniques and their role at the application and infrastructure levels of 6G networks. \\  & [71] & Laid out the architecture for ML-based digital twins for 6G industrial IoT networks and integrated DRL into the design. \\  & [127] & Developed an RL-based framework for measuring the channel collision probability to optimize resource allocation in 6G IoT networks. \\  & [75] & Proposed a DL neural network for the application of 6G cooperative V2V communications that is based on data sharing and coordination. \\ \hline Security & [128] & Designed new key-based physical layer security (PLS) protocols for 6G systems based on the optimum use of time-frequency resources. \\  & [129] & Discussed in depth different security technology enablers in 6G networks and proposed a trustworthy secure telecom operation map. \\  & [130] & Proposed an edge-computing-enabled framework for unified authentication and trust in heterogeneous B5G networks. \\  & [131] & Explored AI-empowered security for 6G networks with an emphasis on energy efficiency and energy-security tradeoffs. \\ \hline Blockchain & [132] & Developed two-hop edge caching using blockchain and PLS technologies to maintain data reliability and secure transmissions. \\  & [133] & Proposed a blockchain-based mobile data access model for fully decentralized, anonymous, and reliable network access. \\  & [134] & Proposed a blockchain-based UAV communications solution for 6G networks for efficient and secure networks. \\  & [135] & Integrated blockchain into the spectrum sharing system of ubiquitous IoT 6G networks to support sharing among different operators. \\ \hline Management & [136] & Proposed a generalized multi-access bandwidth allocation algorithm for beyond 5G passive optical networks. \\  & [137] & Developed a joint allocation scheme with optimization for radio, optical, and mobile edge computing resources in 5G and beyond. \\  & [138] & Studied energy consumption reduction and resource allocation in massive IoT 6G networks via deploying distributed neural networks. \\  & [139] & Developed a multi-dimensional intelligent multiple access scheme to account for the different quality of service requirements in B5G/6G. \\ \hline Architecture & [140] & Discussed the deployment of virtual mobile small cells in 6G based on softwarization, such as network function virtualization (NFV). \\  & [141] & Studied a3D structure of 6G networks that integrated UAVs and satellites and proposed a UAV coverage enhancement algorithm. \\  & [142] & Described a new framework for network slicing in 6G with a focus on modular design, allowing each slice to be self-manageable. \\  & [143] & Deployed edge servers and user plane functions together for 6G networks with a focus on latency minimization. \\ \hline \hline \end{tabular}
\end{table}