Generalized Linear Model Used with an Interferometric Sensor for Enhancing the Measurement of Temperature

In this research, the generalized linear method (GLM) was used to determine the temperature based on some of the features of the spectrum of an interferometric sensor. Normally, in this type of systems have a limited measurement range since ambiguities can occur due to effects of the free spectral range of the interferometer. Moreover, some spectral features, such as the wavelength position of the fringes, can present nonlinear relationships with the temperature. Here it is demonstrated that by applying the generalized linear model the FSR's ambiguities can be overcome and the measurement range can be widened. As a proof of principle results of an experimental sensing arrangement are presented. Additionally, it is shown that by applying the GLM a measurement range from 10 to 40 °C was achieved, which corresponds to 4 FSR periods. Finally, considering as link functions the identity, the logarithm and the logit it was achieved a RMSE of 0.11, 0.29, 0.46, respectively.