An apparatus for measuring bladed rotors, comprising: a microwave sensor configured to radiate a continuous microwave signal toward a bladed rotor and to receive a reflected microwave signal from the bladed rotor; a radio frequency module that generates the microwave signal radiated by the microwave sensor and down-converts the reflected microwave signal into a down-converted signal; and a main processing module configured to generate an output pulse train signal representative of a speed of the bladed rotor based on one of an in-phase portion or a quadrature portion of the down-converted signal, wherein the main processing module comprises a band-pass filter, a tracking filter, a digital pulse generator, and an in-phase/ quadrature output selector (850; 1260), wherein the digital pulse generator comprises in-phase and quadrature pulse generators (1215a, 1215b), the in-phase pulse generator further comprises an in-phase tunable filter that filters the in-phase portion of the band-passed signal based on the control signal, and the quadrature pulse generator further comprises a quadrature tunable filter that filters a quadrature portion of the band-passed signal based on the control signal, wherein the in-phase pulse generator further comprises an in-phase pulse generator that detects zero-crossings of the signal output by the in-phase tunable filter and generates an in-phase pulse train signal based on the in-phase zero-crossings, and the quadrature pulse generator further comprises a quadrature pulse generator that detects zero-crossings of the signal output by the quadrature tunable filter and generates a quadrature pulse train signal based on the quadrature zero-crossings, and wherein the in-phase/ quadrature output selector (850; 1260) is configured to select one of the selected in-phase pulse train signal and the selected quadrature pulse train signal for output as the output pulse train signal representative of the speed of the bladed rotor, and maintain the selection of the one of the pulse train signals for output until a predetermined number of falling or rising edges occurs on another one of the pulse train signals while no falling or rising edges occur on the selected one of the pulse train signals. a microwave sensor configured to radiate a continuous microwave signal toward a bladed rotor and to receive a reflected microwave signal from the bladed rotor; a radio frequency module that generates the microwave signal radiated by the microwave sensor and down-converts the reflected microwave signal into a down-converted signal; and a main processing module configured to generate an output pulse train signal representative of a speed of the bladed rotor based on one of an in-phase portion or a quadrature portion of the down-converted signal, wherein the main processing module comprises a band-pass filter, a tracking filter, a digital pulse generator, and an in-phase/ quadrature output selector (850; 1260), wherein the digital pulse generator comprises in-phase and quadrature pulse generators (1215a, 1215b), the in-phase pulse generator further comprises an in-phase tunable filter that filters the in-phase portion of the band-passed signal based on the control signal, and the quadrature pulse generator further comprises a quadrature tunable filter that filters a quadrature portion of the band-passed signal based on the control signal, wherein the in-phase pulse generator further comprises an in-phase pulse generator that detects zero-crossings of the signal output by the in-phase tunable filter and generates an in-phase pulse train signal based on the in-phase zero-crossings, and the quadrature pulse generator further comprises a quadrature pulse generator that detects zero-crossings of the signal output by the quadrature tunable filter and generates a quadrature pulse train signal based on the quadrature zero-crossings, and wherein the in-phase/ quadrature output selector (850; 1260) is configured to select one of the selected in-phase pulse train signal and the selected quadrature pulse train signal for output as the output pulse train signal representative of the speed of the bladed rotor, and maintain the selection of the one of the pulse train signals for output until a predetermined number of falling or rising edges occurs on another one of the pulse train signals while no falling or rising edges occur on the selected one of the pulse train signals. select one of the selected in-phase pulse train signal and the selected quadrature pulse train signal for output as the output pulse train signal representative of the speed of the bladed rotor, and maintain the selection of the one of the pulse train signals for output until a predetermined number of falling or rising edges occurs on another one of the pulse train signals while no falling or rising edges occur on the selected one of the pulse train signals.