COmpact Antenna SysteM for 5G HomE GaTeway – COMET-5G

While it is not initially included within the three 5G key use cases identified in the reference document of UIT-R published in 2015, broadband Fixed Wireless Access (FWA) is seen by many 5G actors as the first phase of commercial 5G services, to support emerging applications (4K video streaming, Virtual Reality, etc.). Indeed, thanks to the huge amount of spectrum recently released for 5G, including sub-6 GHz bands, FWA allows rapid deployment of novel services at rates sufficiently high to satisfy the needs of future domestic users, at competitive costs in comparison with optical fibre, either in rural areas where the density of homes could not justify an investment in an optical fibre network or in urban/suburban areas where it is not always possible to dig trenches to pass fibre.
The FWA user equipment is generally made of an outdoor unit using directive antenna in LOS of 5G small cell Access Point connected through Power Over Ethernet cable to an indoor unit where received signals are routed towards various home equipment’s. The use of a single indoor unit (5G Gateway), could be very attractive: simplified “all in one” product, reduced installation and equipment cost and more flexibility in choosing where to place the 5G-Gateway. However, it requires to operate in the sub-6GHz bands and combine several technologies including Carrier Aggregation and antenna beamforming. Consequently, several challenges should be addressed such as propagation issues including indoor signal penetration loss, interferences, multipath frequency selective fading, as well as the integration of the 5G radio modules and antennas within an increasingly small box. This implies very stringent requirements from the antenna system side in terms of compactness, number of decorrelated and/or directional reconfigurable radiation patterns, with the possibility of simultaneous operation in multiple frequency bands.
The objective of COMET-5G project is to leverage on recent and ongoing advances on antenna technologies to address the above issues. By developing adequate modeling and simulation electromagnetic tools and pushing further disruptive concepts (Superdirectivity, coupled array, Network Characteristic Mode theory, Spherical Wave Expansion theory), several designs of ultra-compact though efficient, multi-frequency, miniature antenna radiators, grouped in 3D arrangements to optimally occupy and probably shape the volume of the 5G-Gateway will be designed, realized and measured. Then a compelling demonstrator of an indoor 5G box, integrating sub-antenna systems developed within the project, and illustrating the achieved scientific and technological progress, will be prototyped and tested.
The COMET-5G project associates complementary skills of an academic laboratory (IETR-Rennes) specializing in the development of complex antennas, an EPIC (CEA-LETI) European leader in microelectronic technology for telecommunications and an industrial (Technicolor) world leading provider of ultra-broadband access solutions. All the three partners are increasingly working together since many years in collaborative projects, such as the ANR NAOMI project or more recently the ANR SENSAS project.
The scientific ambition of COMET-5G project is to solve the current limitations associated with small-sized antennas in terms of the ability to focus energy in privileged directions and frequency bandwidth requirement. The proposed solutions could then revolutionize the art of designing high gain antennas by making them compact and allowing their use in many applications until then inaccessible due to the incompatible size of the antenna. From the broadband access perspective, the development of a single indoor 5G-box achieving gigabit throughputs, and thus presenting a complete parity in terms of performances with wired networks, will offer a unique opportunity to cable companies and telco’s to enter into new markets, expanding beyond the niches of hybrid or nomadic access.