Abstract: Controlling a multiplexer for switching between probes of a microwave sensor. The multiplexer is used to select one of the probes at any one time of operation of the sensor. Signal processing constants are updated for the selected probe. One or more signal conditioning devices are adjusted to optimize signal noise levels and dynamic range for the probe. The transmit frequency is set for the probe. Upon expiration of a transition period, a data acquisition operation or measurement operation is conducted with the probe. In turn, a time for switching to the next probe is calculated and applied prior to enabling the multiplexer to switch to another probe. These tasks are completed steps for each of the remaining probes of the microwave sensor and then repeated again for continuing operation of the sensor.

Abstract: A temperature measurement technique for calculating a temperature in a high temperature environment by monitoring a change in resonant frequency of a resonant structure loaded with a dielectric material. A response curve for a reflection coefficient S11 associated with the resonant structure is generated, typically by the use of a network analyzer connected to the resonant structure via a cable. A minimum point for the response curve is identified to detect the resonant frequency for the resonant structure. A calibration map is applied to the minimum point to identify a temperature associated with the resonant frequency of the resonant structure. The temperature associated with the resonant frequency of the resonant structure represents the temperature of the high temperature environment.

Abstract: An effective methodology for reducing the influence of clutter arising from a complex signal environment defined by the use of a microwave sensor within or in connection with a gas turbine engine having one or more stages of rotating blades. Accurate detection of peak signals for blade measurements can be obtained by the microwave sensor.

Abstract: A patch antenna for operation within a high temperature environment. The patent antenna typically includes an antenna radiating element, a housing and a microwave transmission medium, such as a high temperature microwave cable. The antenna radiating element typically comprises a metallization (or solid metal) element in contact with a dielectric element. The antenna radiating element can include a dielectric window comprising a flame spray coating or a solid dielectric material placed in front of the radiating element. The antenna element is typically inserted into a housing that mechanically captures the antenna and provides a ground plane for the antenna. Orifices or passages can be added to the housing to improve high temperature performance and may direct cooling air for cooling the antenna.

Abstract: A patch antenna for operation within a high temperature environment. The patent antenna typically includes an antenna radiating element, a housing and a microwave transmission medium, such as a high temperature microwave cable. The antenna radiating element typically comprises a metallization (or solid metal) element in contact with a dielectric element. The antenna radiating element can include a dielectric window comprising a flame spray coating or a solid dielectric material placed in front of the radiating element. The antenna element is typically inserted into a housing that mechanically captures the antenna and provides a ground plane for the antenna. Orifices or passages can be added to the housing to improve high temperature performance and may direct cooling air for cooling the antenna.

Abstract: Calibrating the measurement of a distance between a transceiver and an object such as a radiating element (antenna) or a target by continuously changing the wavelength (frequency) of the transmitted wave and observing the rate of phase shift as a function of change in wavelength. The rate of phase shift change as a function of wavelength can be mathematically related to the total displacement to the reflecting object. This calibration technique is applicable to a sensing device comprising a transceiver configured to transmit a signal toward an object, detectors offset in phase to receive the transmitted signal and a reflected signal, and a processor configured with logic to measure a rate of phase shift proportional to the change in wavelength between the transmitted signal and the reflected signal at the detectors. The processor can be further configured with logic to relate the phase shift to displacement between the transceiver and the reflecting object.

Abstract: Calibrating the measurement of a distance between a transceiver and an object such as a radiating element (antenna) or a target by continuously changing the wavelength (frequency) of the transmitted wave and observing the rate of phase shift as a function of change in wavelength. The rate of phase shift change as a function of wavelength can be mathematically related to the total displacement to the reflecting object. This calibration technique is applicable to a sensing device comprising a transceiver configured to transmit a signal toward an object, detectors offset in phase to receive the transmitted signal and a reflected signal, and a processor configured with logic to measure a rate of phase shift proportional to the change in wavelength between the transmitted signal and the reflected signal at the detectors. The processor can be further configured with logic to relate the phase shift to displacement between the transceiver and the reflecting object.