Composite radome design secures patent, overcomes signal attenuation challenges

Composites manufacturer Exel Composites (Vantaa, Finland) has recently secured a patent across Europe for its telecommunications radome design — a structure that cover antenna systems and radar equipment, offering protection from the environment — which incorporates a closed cell thermoplastic foam in its structure. According to Exel Composites, the use composites overcomes challenges with signal attenuation and improves global broadband speeds.

“The challenges with making a suitable radome involve striking the balance between the attenuation and mechanical structure of the material,” says Juha Pesonen, segment leader for telecommunications at Exel Composites. “Foam has been used in the design for its low density and rigidity, which supports the easy transmission of radio waves. Combined with the mechanical strength of fiberglass skins, we have created a material that is durable, stiff and can provide the protection from the environment that antennae require.”

Developed over a course of four years, the radome’s patent holds a special significance. “Rather than manufacturing the whole radome from the same material density, we can alter it to meet customer requirements so that there is a specific insert creating a window necessary for the radio waves to pass through,” says Kim Sjödahl, senior vice president, Technology and R&D at Exel Composites. Pesonen adds that the combination of fibers, resin and foam can also be tailored to enhance specific properties (e.g. greater mechanical strength, or attenuation in required areas).

The material design’s end goal is to support the increasing roll out of fifth generation (5G) networks and help telecommunications companies to overcome challenges with signal attenuation and protecting devices on the antenna.

“Frequencies have increased rapidly in the last decade, with 5G standards reaching 39 gigahertz (GHz). Our manufacturing capabilities and material expertise allow us to prepare for even higher frequencies, like that of 6G in the future. For the time being, our radome patent will benefit our global network of telecommunications customers, helping them to deliver the latest generation of wireless technology,” Pesonen concludes.

Exel composites aims to roll the patent out across North America and China.