Multiband reconfigurable architectures with antenna boosters for wireless devices

The increase of wireless devices, including wearables, sensors, meters, and trackers, for example has brought about a demand for enhanced performance within constrained dimensions. This demand extends to the antenna systems, which must efficiently operate across various frequency bands while fitting into the limited space available in wireless devices.

Employing complex geometries to design small and multiband antennas is one of the most common methods. The frequency bands of operation depend on the resonant modes of such antenna. To streamline design complexity, antenna booster technology was proposed, where the frequency bands of operation are controlled by the design of a matching network, which is easier and faster than designing an antenna based on complex geometries.

A notable challenge arises when maintaining adaptation across multiple frequency bands, which may be addressed through the use of Antenna Booster Technology in combination with passive matching networks. However, owing to physical principles, the bandwidth cannot be enlarged indefinitely, and therefore, when a large number of bands must be covered, reconfigurable matching networks become a competitive solution. Reconfigurable antennas have become a reality in modern wireless device design. Various design methodologies have been explored, including varactor diodes, PIN diodes, digital tunable capacitors, and RF switches. Among these options, RF switches offer greater versatility due to their ability to provide multiple states and the flexibility to incorporate additional components like capacitors or inductors while providing low insertion loss and power consumption. Nonetheless, these antennas often entail a relatively large physical footprint or involve numerous switches and lumped components. Furthermore, the reconfigurable approach must be tailored to the size of the Printed Circuit Board (PCB) to cover the desired frequency band effectively.

The purpose of this thesis is to address an important challenge still latent in this field, reconfigurable architectures with Antenna Booster Technology for small platform (<~0.2l) , where it is a challenge to obtain bandwidth, capable of covering large frequency bands such as those for cellular applications. Moreover, these proposed architectures are designed to be adaptable across various platforms with different form factors, eliminating the need for altering the bill of materials and relying alter the bill of materials and thus, opening the window of a software-based universal solution.

Keywords: Antenna Booster Technology, reconfigurable antennas, small and multiband antennas, matching networks, tunable components.