Signal transformations around an open-loop fiber gyroscope are identified. This shows that the interferometer performs a derivative. An electronic integrator is used to cancel this effect. Control theory shows that a second integrator can then be used to complete the closed-loop architecture. Variations of this architecture are used by both dual-ramp and serrodyne approaches. The method that these two techniques use to manage the second integrator, and avoid saturation of its output, is described.