Fiber Bragg Gratings (FBGs) are increasingly being employed in a novel range of applications, especially in sensing and measurement field. Some of these novel FBG-based sensing applications, especially those requiring high resolution sensing in harsh environments, impose challenges on Bragg gratings and their performance. Additionally, there is a growing list of Fiber Bragg Grating types and manufacturing techniques, each with its own strengths and disadvantages. With the new generation of fiber optic interrogation technologies reaching femtometer-level resolution in Bragg wavelength tracking, the achievable accuracy and stability of the sensing system is becoming limited by the performance of the employed Bragg grating itself. In many cases, correct selection and definition of the FBG parameters can result in defining the success of the sensing system. Here, we explore the specifications of Bragg gratings that are most relevant to FBG-based sensors, propose their characterization and analysis methodologies and explore their effects for both static and dynamic sensing applications in combination with tunable laser based fiber optic interrogation techniques. Bragg gratings manufactured by several different techniques are compared to demonstrate their suitability for different types of sensing applications. Several application focused examples are also provided to demonstrate the importance of the parameters for detection of strain, pressure, sound, vibration and tilt using fiber optic sensors.
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