Nowadays, telecommunications systems have become an integral part of our daily lives and have an undeniable impact on our private and professional activities. The anyone to anything, anytime, anywhere paradigm, originally conceived for 5G mobile communications networks, is progressively becoming a reality. The primary needs driving this change have been high-throughput mobile connections, reliable low-latency connections, and massive machine-to-machine communications. This trend is leading technological advances in all segments of the ecosystem, where the use of millimeter waves is crucial to implement high-capacity wireless networks. Currently, the electromagnetic spectrum below 6 GHz (sub-6) is highly saturated, so the use of these higher bands allows for a significant increase in data rates. These new millimeter-wave systems are even becoming a valid alternative to copper and fiber connections in urban areas. Their role, already crucial in 5G infrastructure, will be even more important in the future. The 6G network architecture currently being conceived is strongly oriented towards a hierarchical infrastructure, referred to as a vertical heterogeneous network, providing universal coverage by integrating terrestrial, aerial, and space communication links.

This new scenario calls for a new generation of high-efficiency antennas in the millimeter-wave band, being one of the key enabling technologies for the successful deployment of this global network. Due to the heterogeneity of the different nodes and links, the characteristics of the antennas to be developed are very diverse, being possible to use different technologies and typologies. Among other specifications, this project addresses fixed-beam antennas for backhaul links, antennas capable of covering multiple bands, including combinations of mm-wave with sub-6 bands, beam-steerable antennas for communications on the move, or multi-beam antennas for 5G/6G base stations, all of which will be strongly demanded in the next decade.

In addition, the sustainability and affordability of such a huge mm-wave global network demand cost-effective antenna technologies with an enhanced trade-off between fabrication cost and energy efficiency. With this aim, this project investigates different antenna technologies, such as novel versions of gap waveguides with simpler fabrication processes, traveling and leaky-wave radiation mechanisms based on novel slow-wave structures, glide-symmetric holey metasurfaces, or innovative 3D printed configurations. The proposed antenna solutions should be carefully validated through prototyping, with particular attention to low-cost fabrication procedures such as additive manufacturing or conventional printed-circuit-board techniques.

Antennas, Microwaves and Propagation

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