Millimeter-wave and THz technologies for 5G and beyond

Increasing the smart functionalities of mobile devices as well as offering hyper-reality, hyper-connected, and hyper-intelligent services require a continuous expansion of network capacity and reliability. As communication networks move toward 5G and beyond, a higher carrier frequency is required to accommodate the explosive increment of data traffic. Sub-6 GHz frequency bands have been already deployed in early 5G systems, while the millimetre wave band is going to be used to achieve 20 Gb/s cell throughput. For the ultra-wideband wireless transmission in beyond 5G networks, the terahertz (THz) or sub-THz bands are also essential. Higher carrier frequencies imply shorter wireless paths and deeper fiber penetration, where both wireless and optical technologies will play critical roles to push developments beyond the 5G communications era.

Utilizing the mmWave/THz frequency bands for 5G and beyond brings unique and novel challenges to satisfy the requirement of mobile networks. Motivated by the potential of mmWave and THz technologies to open the future of mobile communications, this special issue seeks to find key enabling technologies. These include mmWave/THz generation and detection, frontend and antenna design, wave propagation and channel modelling, radio-over-fiber transmission, base band signal transmission, and so on.

Topics of interests include but are not limited to the following:

• mmWave/THz wave propagation and channel modelling
• mmWave/THz generation and detection
• photonic-mixer and optoelectronics devices
• Radio-over-fiber transmission
• High power mmWave/THz amplifier
• RF frontend and antenna design
• Baseband signal processing
• Wireless and optical technologies for mobile fronthaul and backhaul
• Optical networking for mmWave/THz wireless systems
• mmWave and THz prototypes, testbeds, and demonstration

We are particularly interested in millimetre and THz (including sub-THz) technologies for beyond 5G technologies such as wave propagation and channel modelling, mmWave/THz generation and detection, frontend and antenna, base band signal processing, and mmWave and THz prototype, testbeds, and demonstrations.

We welcome original research articles positioning some novel communication and transceiver or feasibility demonstration to open future communications network, original research articles reporting recent results, implementation and performance evaluation for these technologies and systematic review articles presenting open questions and challenges for beyond communications and networking technologies.