In this article, Fiber Bragg Grating (FBG) technology used to implement fiber sensors is explained and some applications in temperature and strain measurements are presented. In the first section, the fundamentals and operation principles of FBGs are shown as well as optical fiber sensing interrogators. The second part of the article presents applications of temperature measurements in power transmission lines, shrinkage measurements in concrete structures, and spatiotemporal measurement variations in variations of temperature between groundwater and surface water (GW-SW).

This work presents a comparison between Orthogonal Frequency Division Multiplexing OFDM and Generalized Frequency Division Multiplexing GFDM to evaluate the latency and bit error rate in a Fiber-wireless link in 3.5 GHz band using Software Defined Radio SDR, taking into account its feasibility for the 5G networks in the future.

In this paper the implementation of a low cost Fiber Bragg Grating (FBG) sensor interrogation system is presented. It uses two FBGs for comparison and measures the power between the FBGs signals using an embedded system. The system has been implemented for the 1550 nm band. The performance of the system was tested with a broadband source and doing temperature variations in one of the two FBGs, obtaining a response from 0°C to 60°C.

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.

Reliability of optical fiber Bragg grating sensors is evaluated, for measuring strain and temperature inside concrete beam structures during the first 24 hours, where occurs more than the 70% of the total shrinkage of concrete