A microwave ablation system incorporates a microwave thermometer that couples to a microwave transmission network connecting a microwave generator to a microwave applicator to measure noise temperature. The noise temperature is processed to separate out components of the noise temperature including the noise temperature of the tissue being treated and the noise temperature of the microwave transmission network. The noise temperature may be measured by a radiometer while the microwave generator is generating the microwave signal or during a period when the microwave signal is turned off. The microwave ablation system may be configured as a modular system having one or more thermometry network modules that are connectable between a microwave applicator and a microwave generator. Alternatively, the modular system includes a microwave generator, a microwave applicator, and a microwave cable that incorporate a microwave thermometry network module.

A method for calculating a value representative of a downhole temperature in a hydrocarbon well, wherein the well includes production tubing inside an outer tubing, an annulus is provided between the production tubing and the outer tubing, and the annulus receives a hydraulic control line supplying hydraulic fluid for the control of a downhole device, the method including sensing the pressure of hydraulic fluid in the control line at the wellhead, and using a measurement of the pressure to calculate the value representative of the downhole temperature.

A method for calculating a value representative of a downhole temperature in a hydrocarbon well, wherein the well includes production tubing inside an outer tubing, an annulus is provided between the production tubing and the outer tubing, and the annulus receives a hydraulic control line supplying hydraulic fluid for the control of a downhole device, the method including sensing the pressure of hydraulic fluid in the control line at the wellhead, and using a measurement of the pressure to calculate the value representative of the downhole temperature.

Some aspects of the present disclosure feature a sensing device comprising a magnetic bias layer, a resonator, a spacer, and a housing. The spacer includes an environmental change receptor. The thickness of the environmental change receptor rapidly increases in response to a change to an environment variable.

Some aspects of the present disclosure feature a sensing device comprising a magnetic bias layer, a resonator, a spacer, and a housing. The spacer includes an environmental change receptor. The thickness of the environmental change receptor rapidly increases in response to a change to an environment variable.

This patent application discloses techniques and devices for sensing or measuring electric currents and/or temperature based on photonic sensing techniques. An optical current sensor head is located near or at a current-carrying conductor so that a magnetic field associated with the current is present at a Faraday material and the optical detection unit detects the light from the Faraday material to determine a magnitude of the current. An optical temperature sensor head is located near or at a location so that the temperature at a temperature-sensing Faraday material is reflected by the optical polarization rotation which is detected to determine the temperature.

This patent application discloses techniques and devices for sensing or measuring electric currents and/or temperature based on photonic sensing techniques. An optical current sensor head is located near or at a current-carrying conductor so that a magnetic field associated with the current is present at a Faraday material and the optical detection unit detects the light from the Faraday material to determine a magnitude of the current. An optical temperature sensor head is located near or at a location so that the temperature at a temperature-sensing Faraday material is reflected by the optical polarization rotation which is detected to determine the temperature.

A thermal event sensor includes a charge storage component formed on a substrate, configured to hold an initial charge, and configured to lose charge at a rate dependent upon temperature. A sensing interface is coupled to the charge storage component and a readout mechanism is coupled to the sensing interface. The readout mechanism senses a remaining charge on the charge storage component and provides a readout value indicative of the remaining charge.

A thermometer includes a substrate; an optical resonator disposed on the substrate and including an optical resonance, the optical resonator being configured to receive a resonant frequency corresponding to the optical resonance; and a waveguide disposed on the substrate proximate to the optical resonator to receive input light, to communicate the resonant frequency to the optical resonator, and to transmit output light; wherein an aperture is interposed between: the substrate and the optical resonator, the substrate and the waveguide, or a combination comprising at least one of the foregoing, and the thermometer is configured to change the optical resonance in response to a change in temperature of the optical resonator.

A thermometer includes a substrate; an optical resonator disposed on the substrate and including an optical resonance, the optical resonator being configured to receive a resonant frequency corresponding to the optical resonance; and a waveguide disposed on the substrate proximate to the optical resonator to receive input light, to communicate the resonant frequency to the optical resonator, and to transmit output light; wherein an aperture is interposed between: the substrate and the optical resonator, the substrate and the waveguide, or a combination comprising at least one of the foregoing, and the thermometer is configured to change the optical resonance in response to a change in temperature of the optical resonator.