This work presents a system for the interrogation of fiber- optic Bragg grating sensors based on time domain reflectometry and Bragg grating fixed filters. Using a pulsed light source, the spectral position of the sensor is related to the ratio of two pulses intensities, making detection independent of intensity variations. Theoretical and experimental aspects regarding the working principles of this technique are discussed. Since filtering is accomplished with Bragg grating so that only one photodetection circuit is used and a reduced number of optic couplers/circulators are needed, the system provides a considerable reduction in the cost of interrogation for a set of sensors. Using only one photodetection circuit also has the advantage of maintaining the same characteristics for all pulses, thus minimizing external influences in this circuit, such as variations in the environment temperature. A test stand was assembled for the interrogation of six sensors. Comparisons between experimental and simulated results show a good agreement. Extrapolations indicate that it would be possible to interrogate sensors with a spectral variation of 2 nanometers, with uncertainties lower than 10 pm, which is adequate for temperature sensors. Cross talk analyses between two adjacent channels show small influence between them, and approaches to reduce this interference are presented.