A new cavity-backed antenna compatible with planar technology is designed, manufactured, and measured. The original design consists of a slotted cavity fed by a microstrip line. This allows the implementation of the feeding line and the cavity on a single substrate, compatible with a standard printed circuit board (PCB) or low-temperature cofired ceramic (LTCC) process. The idea is to combine specific slot patterns on the cavity back face such as meandered and edge slots. An example is presented, and the measurements show minimum 10-dB return loss bandwidth of 1.32%, 8.5 dBi gain, and 21 dB front-to-back ratio. The combination of volume cavity, planar feeding, and antenna layout, leads to light weight, easy fabrication, and easy integration with planar circuits.

This paper presents a temperature study of cellular spheroids of the line MCF-07 under a hyperthermia (HT) treatment. A 3D printed culture plate embedded with optical fiber Bragg grating (FBG) sensors was designed to perform real-time temperature measurements of the spheroids. The proposed culture plate preserves the fiber sensors' integrity and functionality while remaining immune to the high electromagnetic interference scenario. A custom microwave applicator was designed to eliminate direct contact between the heating element and the samples, while considering the culture plate material's permittivity to ensure efficient heating. The heating setup maintains the samples' temperature within the HT range, which is crucial for predicting treatment outcomes. The sensors embedded in the designed culture plate achieved an accuracy within 0.31 ${}^\mathrm{C}$ . Initial observations of the temperature effects on spheroids are discussed, highlighting the potential of this approach to understand how temperature variations within the HT range affect cell cultures.