Apparatus and method to identify and measure gas concentrations
Inventors
Uplinger, II, James Robert • Nichol, Robert M. • Keller, Walter John
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-10448864-B1
Publication Date
2019-10-22
Expiration Date
Abstract
A method and apparatus is provided for the analysis of gaseous compounds, especially for determining the concentration of a gas or gases in a gas mixture by microwave spectroscopy. Microwave radiation is generated at one or more frequencies the gas is most responsive to, transmitted by antenna, passed through the gas under test, received by antenna, and the absorption and/or reflection of the microwave radiation is measured by means such as digitization and analysis using the FFT spectrum versus energy response generated, the response subsequently used to calculate the gas concentration.
Core Innovation
The invention provides an apparatus for determining a concentration of gasses in a gas mixture by using microwave generator tuned to responsive frequencies of the gas mixture. A transmit antenna transmits an electromagnetic energy emission spectrum through the gas mixture in response to microwave radiation coupled to the transmit antenna, and a receive antenna spaced from the transmit antenna captures an electromagnetic energy difference between the electromagnetic energy emission spectrum transmitted from the transmit antenna and an electromagnetic energy emission spectrum being absorbed or reflected by gaseous molecules in the gas mixture.
The apparatus includes a hollow enclosure, an intake member attached to the hollow enclosure configured to introduce the gas mixture, and an evacuation member attached to the hollow enclosure configured to evacuate the gas mixture. The receiver is coupled to the receive and/or transmit antenna and converts the electromagnetic energy difference into a digital signal, and a control member processes the digital signal in accordance with one or more algorithms and determines concentration(s) of gasses in the gas mixture based on analysis of the electromagnetic energy difference.
In at least one configuration, the control member measures at least one of an absorption amplitude, an emission amplitude and a reflection amplitude in the digital signal, converts the at least one of the absorption amplitude, the emission amplitude and the reflection amplitude to an absolute concentration, and compares the absolute concentration against a stored value. The control member is configured to measure, convert, and compare to support determination of concentration(s) of gasses in the gas mixture.
Claims Coverage
The document presents two independent claims. Both claims share the same core microwave transmission/reception approach and differ in the specific nature of the concentration determination, with one claim reciting general algorithmic determination and the other reciting amplitude-to-absolute concentration conversion and comparison against a stored value.
Microwave transmission through a flowing gas mixture
A hollow enclosure with an intake member and an evacuation member, where at least one microwave generator tuned to responsive frequencies transmits an electromagnetic energy emission spectrum through the gas mixture, and a receive antenna spaced from the transmit antenna captures an electromagnetic energy difference involving absorption or reflection by gaseous molecules.
Conversion of captured electromagnetic energy difference into a digital signal for algorithmic concentration determination
A receiver coupled to the receive and/or transmit antenna converts the electromagnetic energy difference into a digital signal, and a control member processes the digital signal in accordance with one or more algorithms to analyze the electromagnetic energy difference and determine concentration(s) of gasses in the gas mixture.
Amplitude measurement and conversion to absolute concentration with comparison to a stored value
A control member configured to measure, in the digital signal, at least one of an absorption amplitude, an emission amplitude and a reflection amplitude, convert the at least one of the absorption amplitude, the emission amplitude and the reflection amplitude to an absolute concentration, and compare the absolute concentration against a stored value.
Overall, the claim set covers a microwave spectroscopy apparatus using a hollow enclosure with intake and evacuation, spaced transmit and receive antennas with a gas flow between them, receiver conversion of an absorbed or reflected electromagnetic energy difference into a digital signal, and control-member algorithms to determine gas concentrations, with one independent claim specifically requiring conversion from absorption, emission, or reflection amplitudes to absolute concentration and comparison against stored values.
Stated Advantages
Not explicitly described in patent.
Documented Applications
Not explicitly described in patent.
Interested in licensing this patent?