Systems and methods are described herein for extracting inertial information from nonlinear periodic signals. A system for determining an inertial parameter can include circuitry configured for receiving a first periodic analog signal from a first sensor that is responsive to motion of a proof mass, converting the first periodic analog signal to a first periodic digital signal, determining a result of trigonometrically inverting a quantity, the quantity based on the first periodic digital signal, and determining the inertial parameter based on the result.