Nanosatellite constellations are becoming an increasingly popular means of deploying IoT services worldwide. Startup Kinéis, based in Toulouse, France, is now giving some of its IoT devices hybrid terrestrial and satellite radio (in the 400 MHz band) connectivity. This kind of low-frequency communication uses less power for extended device battery life. But the lower the communication frequency, the larger the antenna. This creates obvious challenges for smaller devices.
CEA-Leti, which boasts a strong track record designing and integrating miniature antennas, is working on this project with Kinéis to shrink the antennas by a factor of 7.5. Distributed loading techniques will be used on the antenna, effectively emulating a larger antenna size, and the design will be modified to maintain the same level of performance as the original antenna. Another major constraint that has never been addressed until now is the fact that the antenna's radiation pattern has to be circularly polarized.
According to initial testing, an antenna no larger than 5 cm will soon come off the drawing board. This kind of antenna will keep people, animals, products, and environmental sensors, for example, connected wherever they are on the planet, opening the door to a wide range of potential use cases.