• ​IoT radio link frequencies are decreasing due to their range and connection robustness. The outcome of this is longer wavelengths and larger antennas: their size usually being a quarter of the wavelength.  So, how can we put a stop to this escalation? CEA-Leti's latest research provides an answer to this since it opens the door to miniaturized antennas that are only 1/15^th of the wavelength.

• These miniaturized antennas would normally lose much of their radiation efficiency. But this drawback has been overcome by reducing their instantaneous bandwidth to that of the emitted signal, i.e. approximately 500 kHz. For the antenna to operate throughout the application bandwidth, it integrates digital control of its resonance frequency by RF components and can therefore switch from one signal bandwidth to the other.
  

A model for optimizing RF component implementation

The small scale of our antennas is so significant that usual electromagnetic simulation tools are unsuitable", says CEA-Leti's Serge Bories. Rana Berro, the PhD student heading up the project, has designed a new analytical model to evaluate their impedance efficiency.

• This model is much faster than usual simulation tools and enables design tests to be multiplied to optimize RF component size and arrangement on the antenna. This aspect forms the object of a patent.

• These promising developments remain to be confirmed by building and validating prototypes: Rana Berro will dedicate her final thesis year to these activities. However, several manufacturers have approached CEA-Leti and are interested in this miniaturized antenna even before completion of prototype building and validation.