Patent US5763283A successfully refreshed from Google Patents.
US5763283A
Expired / Lapsed
US
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Method and apparatus for phase for and amplitude detection
Assignee: National Technology and Engineering Solutions of Sandia LLC
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Filing: 1994-10-12
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Granted: 1998-06-09
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Expires: 2014-10-12
Abstract
Abstract A new class of techniques been developed which allow inexpensive application of SAW-type chemical sensor devices while retaining high sensitivity (ppm) to chemical detection. The new techniques do not require that the sensor be part of an oscillatory circuit, allowing large concentrations of, e.g., chemical vapors in air, to be accurately measured without compromising the capacity to measure trace concentrations. Such devices have numerous potential applications in environmental monitoring, from manufacturing environments to environmental restoration.
Inventors
- 👤 Richard W. Cernosek
- 👤 Gregory C. Frye
- 👤 Stephen J. Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:49
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/02; G01N29/022; G01N2291/00; G01N2291/01; G01N2291/014; G01N2291/015; G01N2291/02; G01N2291/025; G01N2291/0256; G01N2291/04; G01N2291/042; G01N2291/0423; Y; Y10; Y10T; Y10T436/00; Y10T436/21
Claims Analysis
Total Claims: 116
Claim 1
Independent Claim
67 words
A method for measuring chemical concentrations, comprising mixing the in- and out-of-phase components of a radio-frequency reference signal with a second signal, initially coherent with said reference signal, said second signal having passed through a chemical sensor having an electrical delay time and signal attenuation which depend on chemical concentration, said mixing producing output voltages reflecting the electrical delay time and signal attenuation of said chemical sensor.
Claim 2
Independent Claim
67 words
A method for measuring chemical concentrations, comprising mixing the in- and out-of-phase components of a radio-frequency reference signal with a second signal, initially coherent with said reference signal, said second signal having passed through a chemical sensor having an electrical delay time and signal attenuation which depend on chemical concentration, said mixing producing output voltages reflecting the electrical delay time and signal attenuation of said chemical sensor.
Claim 3
Independent Claim
309 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source, having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal in two nominally equal outputs; c) a chemical sensor having a sensor input port connected to the first signal output port of said first signal splitter, and a sensor output port; d) a second signal splitter, having an input port connected to the sensor output port of said chemical sensor and a first and second signal output port, which divide the second signal splitter input signal into two nominally equal outputs; e) a third signal splitter, having an input port connected to the second signal output port of said first signal splitter and a first and a second signal output port, said output ports of the third signal splitter providing outputs substantially equal in average voltage and substantially 90° out of phase with each other; f) a first radio-frequency mixer having two input ports, one input port connected to the first signal output port of said second signal splitter and the other input port connected to the first signal output port of said third signal splitter, and an output port delivering a direct-current voltage output V 1 ; g) a second radio-frequency mixer having two input ports, one input port connected to the second signal output port of said second signal splitter and the other input port connected to the second signal output port of said third signal splitter, and an output port delivering a direct-current voltage output V 2 , and; h) means for measuring and converting said voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensor.
Claim 4
Independent Claim
309 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source, having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal in two nominally equal outputs; c) a chemical sensor having a sensor input port connected to the first signal output port of said first signal splitter, and a sensor output port; d) a second signal splitter, having an input port connected to the sensor output port of said chemical sensor and a first and second signal output port, which divide the second signal splitter input signal into two nominally equal outputs; e) a third signal splitter, having an input port connected to the second signal output port of said first signal splitter and a first and a second signal output port, said output ports of the third signal splitter providing outputs substantially equal in average voltage and substantially 90° out of phase with each other; f) a first radio-frequency mixer having two input ports, one input port connected to the first signal output port of said second signal splitter and the other input port connected to the first signal output port of said third signal splitter, and an output port delivering a direct-current voltage output V 1 ; g) a second radio-frequency mixer having two input ports, one input port connected to the second signal output port of said second signal splitter and the other input port connected to the second signal output port of said third signal splitter, and an output port delivering a direct-current voltage output V 2 , and; h) means for measuring and converting said voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensor.
Claim 5
Dependent Claim
13 words
The apparatus of claim 2, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 6
Dependent Claim
20 words
The apparatus of claim 2, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 7
Independent Claim
161 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal in two nominally equal outputs; c) a chemical sensor having a sensor input port connected to the first signal output port of said first signal splitter and a sensor output port; d) an in-phase and quadrature-phase demodulator, having a local oscillator input port connected to the second signal output port of said first signal splitter, a radio-frequency input port connected to the sensor output port, and first and second output ports which deliver direct-current voltage outputs V 1 and V 2 , respectively, and; e) means for measuring and converting said voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensor.
Claim 8
Independent Claim
161 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal in two nominally equal outputs; c) a chemical sensor having a sensor input port connected to the first signal output port of said first signal splitter and a sensor output port; d) an in-phase and quadrature-phase demodulator, having a local oscillator input port connected to the second signal output port of said first signal splitter, a radio-frequency input port connected to the sensor output port, and first and second output ports which deliver direct-current voltage outputs V 1 and V 2 , respectively, and; e) means for measuring and converting said voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensor.
Claim 9
Dependent Claim
13 words
The apparatus of claim 5, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 10
Dependent Claim
20 words
The apparatus of claim 5, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 11
Dependent Claim
25 words
The apparatus of claim 5, further comprising boosting amplifiers to insure adequate signal level at the local oscillator and radio-frequency input ports of the demodulator.
Claim 12
Independent Claim
247 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal into two nominally equal outputs; c) a second signal splitter, having an input port connected to the first signal output port of the first signal splitter and N signal output ports which divide the second signal splitter input signal into N nominally equal outputs; d) N chemical sensors, each having a sensor input port connected to a respective signal output port of said first signal splitter and a sensor output port; e) a third signal splitter, having an input port connected to the second signal output port of the first signal splitter and N signal output ports which divide the third signal splitter input signal into N nominally equal outputs; f) N in-phase and quadrature-phase demodulators, each having a local oscillator input port connected to a respective signal output port of said second signal splitter, a radio-frequency input port connected to a respective sensor output port, and a pair of output ports, each demodulator thereby delivering direct-current voltage outputs V 1 and V 2 , and; g) means for measuring and converting said N sets of voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensors.
Claim 13
Independent Claim
247 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal into two nominally equal outputs; c) a second signal splitter, having an input port connected to the first signal output port of the first signal splitter and N signal output ports which divide the second signal splitter input signal into N nominally equal outputs; d) N chemical sensors, each having a sensor input port connected to a respective signal output port of said first signal splitter and a sensor output port; e) a third signal splitter, having an input port connected to the second signal output port of the first signal splitter and N signal output ports which divide the third signal splitter input signal into N nominally equal outputs; f) N in-phase and quadrature-phase demodulators, each having a local oscillator input port connected to a respective signal output port of said second signal splitter, a radio-frequency input port connected to a respective sensor output port, and a pair of output ports, each demodulator thereby delivering direct-current voltage outputs V 1 and V 2 , and; g) means for measuring and converting said N sets of voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensors.
Claim 14
Dependent Claim
13 words
The apparatus of claim 9, wherein said N chemical sensors comprise surface-acoustic-wave devices.
Claim 15
Dependent Claim
83 words
The apparatus of claim 10, further comprising a reference surface-acoustic-wave device not sensitive to the chemical environment having reference device input and output ports, intercalated in the connection between said second output port of the first signal splitter and said input port of the third signal splitter so that said reference device input port is connected to the second output port of the first signal splitter and said reference device output port is connected to said input port of the third signal splitter.
Claim 16
Dependent Claim
24 words
The apparatus of claim 9, wherein said means for measuring and converting comprise a computer-controlled voltmeter, a signal switching system, and a computer system.
Claim 17
Dependent Claim
20 words
The apparatus of claim 9, wherein said means for measuring and converting comprises N computer-controlled voltmeters and a computer system.
Claim 18
Dependent Claim
16 words
The apparatus of claim 9, wherein said means for measuring and converting comprises a neural net.
Claim 19
Dependent Claim
17 words
The apparatus of claim 9, wherein said means for measuring and converting comprises means for pattern recognition.
Claim 20
Dependent Claim
19 words
The apparatus of claim 9, further comprising a common test case within which said N chemical sensors are mounted.
Claim 21
Independent Claim
195 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source, a first set of N signal output ports and a second set of N signal output ports, which divide the first signal splitter input signal into 2N nominally equal outputs; c) N chemical sensors, each having a sensor input port connected to a respective signal output port from the first set of N signal output ports of said first signal splitter, and a sensor output port; d) N in-phase and quadrature-phase demodulators, each having a local oscillator input port connected to a respective signal output port from the second set of N signal output ports of said second signal splitter, a radio-frequency input port connected to a respective sensor output port, and a pair of output ports, each demodulator thereby delivering direct-current voltage outputs V 1 and V 2 , and; e) means for measuring and converting said N sets of voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensors.
Claim 22
Independent Claim
195 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source, a first set of N signal output ports and a second set of N signal output ports, which divide the first signal splitter input signal into 2N nominally equal outputs; c) N chemical sensors, each having a sensor input port connected to a respective signal output port from the first set of N signal output ports of said first signal splitter, and a sensor output port; d) N in-phase and quadrature-phase demodulators, each having a local oscillator input port connected to a respective signal output port from the second set of N signal output ports of said second signal splitter, a radio-frequency input port connected to a respective sensor output port, and a pair of output ports, each demodulator thereby delivering direct-current voltage outputs V 1 and V 2 , and; e) means for measuring and converting said N sets of voltage outputs V 1 and V 2 into information about the chemical environment of said chemical sensors.
Claim 23
Independent Claim
12 words
The apparatus of claim wherein said N chemical sensors comprise surface-acoustic-wave devices.
Claim 24
Dependent Claim
24 words
The apparatus of claim 17, wherein said means for measuring and converting comprise a computer-controlled voltmeter, a signal switching system, and a computer system.
Claim 25
Dependent Claim
20 words
The apparatus of claim 17, wherein said means for measuring and converting comprises N computer-controlled voltmeters and a computer system.
Claim 26
Dependent Claim
16 words
The apparatus of claim 17, wherein said means for measuring and converting comprises a neural net.
Claim 27
Dependent Claim
17 words
The apparatus of claim 17, wherein said means for measuring and converting comprises means for pattern recognition.
Claim 28
Dependent Claim
19 words
The apparatus of claim 17, further comprising a common test case within which said N chemical sensors are mounted.
Claim 29
Independent Claim
211 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a splitter, having a splitter input port connected to said output port of the source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) a variable phase shifter, having a reference input port connected to the second splitter output port, a control input port, and a shifted reference output port; e) an in-phase and quadrature-phase demodulator, having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected to the shifted reference output port, a first output port and a second output port; f) a control feedback circuit, having an input port connected to the second output port of the demodulator and an output port connected to the control input port of the variable phase shifter, and; g) means for measuring and converting the voltage at the first output port of the demodulator and the voltage at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 30
Independent Claim
211 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a splitter, having a splitter input port connected to said output port of the source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) a variable phase shifter, having a reference input port connected to the second splitter output port, a control input port, and a shifted reference output port; e) an in-phase and quadrature-phase demodulator, having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected to the shifted reference output port, a first output port and a second output port; f) a control feedback circuit, having an input port connected to the second output port of the demodulator and an output port connected to the control input port of the variable phase shifter, and; g) means for measuring and converting the voltage at the first output port of the demodulator and the voltage at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 31
Dependent Claim
13 words
The apparatus of claim 24, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 32
Dependent Claim
20 words
The apparatus of claim 24, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 33
Independent Claim
329 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal into two nominally equal outputs; c) a second signal splitter, having an input port connected to the first signal output port of the first signal splitter and N signal output ports which divide the second signal splitter input signal into N nominally equal outputs; d) N chemical sensors, each having a sensor input port connected to a respective signal output port of said first signal splitter and a sensor output port; e) a third signal splitter, having an input port connected to the second signal output port of the first signal splitter and N signal output ports which divide the third signal splitter input signal into N nominally equal outputs; f) N variable phase shifters, each having an input port connected to a respective signal output port of the third signal splitter, a control input port, and a shifted reference signal output port; g) N in-phase and quadrature-phase demodulators, each having a local oscillator input port connected to the shifted reference signal output port of a respective variable phase shifter, a radio-frequency input port connected to a respective sensor output port, a first output port, and a second output port; h) N control feedback circuits, each having an input port connected to the second output port of a respective demodulator and an output port connected to the control input port of the variable phase shifter whose shifter reference signal output port is connected to the aforementioned demodulator, and; i) means for measuring and converting the voltage of the first output port of each demodulator and the voltage at the respective control feedback circuit output port into information about the chemical environment of said chemical sensors.
Claim 34
Independent Claim
329 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal into two nominally equal outputs; c) a second signal splitter, having an input port connected to the first signal output port of the first signal splitter and N signal output ports which divide the second signal splitter input signal into N nominally equal outputs; d) N chemical sensors, each having a sensor input port connected to a respective signal output port of said first signal splitter and a sensor output port; e) a third signal splitter, having an input port connected to the second signal output port of the first signal splitter and N signal output ports which divide the third signal splitter input signal into N nominally equal outputs; f) N variable phase shifters, each having an input port connected to a respective signal output port of the third signal splitter, a control input port, and a shifted reference signal output port; g) N in-phase and quadrature-phase demodulators, each having a local oscillator input port connected to the shifted reference signal output port of a respective variable phase shifter, a radio-frequency input port connected to a respective sensor output port, a first output port, and a second output port; h) N control feedback circuits, each having an input port connected to the second output port of a respective demodulator and an output port connected to the control input port of the variable phase shifter whose shifter reference signal output port is connected to the aforementioned demodulator, and; i) means for measuring and converting the voltage of the first output port of each demodulator and the voltage at the respective control feedback circuit output port into information about the chemical environment of said chemical sensors.
Claim 35
Dependent Claim
12 words
The apparatus of claim 27, wherein N chemical sensors comprise surface-acoustic-wave devices.
Claim 36
Dependent Claim
83 words
The apparatus of claim 28, further comprising a reference surface-acoustic-wave device not sensitive to the chemical environment having reference device input and output ports, intercalated in the connection between said second output port of the first signal splitter and said input port of the third signal splitter so that said reference device input port is connected to the second output port of the first signal splitter and said reference device output port is connected to said input port of the third signal splitter.
Claim 37
Dependent Claim
24 words
The apparatus of claim 27, wherein said means for measuring and converting comprise a computer-controlled voltmeter, a signal switching system, and a computer system.
Claim 38
Dependent Claim
20 words
The apparatus of claim 27, wherein said means for measuring and converting comprises N computer-controlled voltmeters and a computer system.
Claim 39
Dependent Claim
16 words
The apparatus of claim 27, wherein said means for measuring and converting comprises a neural net.
Claim 40
Dependent Claim
17 words
The apparatus of claim 27, wherein said means for measuring and converting comprises means for pattern recognition.
Claim 41
Dependent Claim
19 words
The apparatus of claim 27, further comprising a common test case within which said N chemical sensors are mounted.
Claim 42
Independent Claim
189 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a variable frequency source having a control input port and a radio-frequency output port; b) a splitter, having a splitter input port connected to said output port of the variable frequency source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) an in-phase and quadrature-phase demodulator, having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected the second splitter output port, a first output port and a second output port; e) a control feedback circuit, having an input port connected to the second output port of the demodulator and an output port connected to the control input port of the variable frequency source, and; f) means for measuring and converting voltages at the first output port of the demodulator and at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 43
Independent Claim
189 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a variable frequency source having a control input port and a radio-frequency output port; b) a splitter, having a splitter input port connected to said output port of the variable frequency source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) an in-phase and quadrature-phase demodulator, having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected the second splitter output port, a first output port and a second output port; e) a control feedback circuit, having an input port connected to the second output port of the demodulator and an output port connected to the control input port of the variable frequency source, and; f) means for measuring and converting voltages at the first output port of the demodulator and at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 44
Dependent Claim
13 words
The apparatus of claim 35, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 45
Dependent Claim
20 words
The apparatus of claim 35, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 46
Dependent Claim
15 words
The apparatus of claim 35, wherein said control feedback circuit further comprises a gain control.
Claim 47
Dependent Claim
25 words
The apparatus of claim 38, wherein said gain control is set to keep the output voltage of the control feedback circuit between nominally ±5 volts.
Claim 48
Dependent Claim
22 words
The apparatus of claim 38, wherein the output voltage of the control feedback circuit is a simple multiple of the chemical concentration.
Claim 49
Dependent Claim
35 words
The apparatus of claim 35, further comprising zeroing means to set the output voltage of the control feedback circuit to zero when said chemical sensor is not exposed to chemicals to which it is sensitive.
Claim 50
Dependent Claim
15 words
The apparatus of claim 35, wherein said means for measuring and converting comprise a voltmeter.
Claim 51
Dependent Claim
18 words
The apparatus of claim 35, wherein said means for measuring and converting comprise a variable-gain voltage measuring device.
Claim 52
Independent Claim
200 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a splitter, having a splitter input port connected to said output port of the source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) a variable phase shifter, having a reference input port connected to the second splitter output port, a control input port, and a shifted reference output port; e) a mixer with low pass filter having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected to the shifted reference output port, and an intermediate-frequency voltage output port; f) a control feedback circuit, having an input port connected to the intermediate frequency voltage output port of the mixer and an output port connected to the control input port of the variable phase shifter, and; g) means for measuring and converting a voltage at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 53
Independent Claim
200 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a splitter, having a splitter input port connected to said output port of the source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) a variable phase shifter, having a reference input port connected to the second splitter output port, a control input port, and a shifted reference output port; e) a mixer with low pass filter having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected to the shifted reference output port, and an intermediate-frequency voltage output port; f) a control feedback circuit, having an input port connected to the intermediate frequency voltage output port of the mixer and an output port connected to the control input port of the variable phase shifter, and; g) means for measuring and converting a voltage at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 54
Dependent Claim
13 words
The apparatus of claim 44, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 55
Dependent Claim
20 words
The apparatus of claim 44, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 56
Dependent Claim
25 words
The apparatus of claim 44, further comprising boosting amplifiers to insure adequate signal level at the local oscillator and radio-frequency input ports of the mixer.
Claim 57
Dependent Claim
15 words
The apparatus of claim 44, wherein said control feedback circuit further comprises a gain control.
Claim 58
Dependent Claim
25 words
The apparatus of claim 48, wherein said gain control is set to keep the output voltage of the control feedback circuit between nominally ±5 volts.
Claim 59
Dependent Claim
22 words
The apparatus of claim 48, wherein the output voltage of the control feedback circuit is a simple multiple of the chemical concentration.
Claim 60
Dependent Claim
36 words
The apparatus of claim 44, further comprising zeroing means for setting the output voltage of the control feedback circuit to zero when said chemical sensor is not exposed to chemicals to which the apparatus is sensitive.
Claim 61
Dependent Claim
15 words
The apparatus of claim 44, wherein said means for measuring and converting comprise a voltmeter.
Claim 62
Dependent Claim
18 words
The apparatus of claim 44, wherein said means for measuring and converting comprise a variable-gain voltage measuring device.
Claim 63
Independent Claim
315 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal into two nominally equal outputs; c) a second signal splitter, having an input port connected to the first signal output port of the first signal splitter and N signal output ports which divide the second signal splitter input signal into N nominally equal outputs; d) N chemical sensors, each having a sensor input port connected to a respective signal output port of said first signal splitter and a sensor output port; e) a third signal splitter, having an input port connected to the second signal output port of the first signal splitter and N signal output ports which divide the third signal splitter input signal into N nominally equal outputs; f) N variable phase shifters, each having an input port connected to a respective signal output port of the third signal splitter, a control input port, and a shifted reference signal output port; g) N mixers, each having a low-pass filter, a local oscillator input port connected to the shifted reference signal output port of a respective variable phase shifter, a radio-frequency input port connected to a respective sensor output port, and an intermediate-frequency voltage output port; h) N control feedback circuits, each having an input port connected to the intermediate-frequency voltage output port of one of the mixers, and an output port connected to the control input port of the variable phase shifter whose shifter reference signal output port is connected to the aforementioned mixer, and; i) means for measuring and converting voltages at the control feedback circuit output ports into information about the chemical environment of said chemical sensors.
Claim 64
Independent Claim
315 words
An apparatus for measuring the chemical environment of multiple chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first signal splitter, having an input port connected to the output port of said source and a first and a second signal output port, which divide the first signal splitter input signal into two nominally equal outputs; c) a second signal splitter, having an input port connected to the first signal output port of the first signal splitter and N signal output ports which divide the second signal splitter input signal into N nominally equal outputs; d) N chemical sensors, each having a sensor input port connected to a respective signal output port of said first signal splitter and a sensor output port; e) a third signal splitter, having an input port connected to the second signal output port of the first signal splitter and N signal output ports which divide the third signal splitter input signal into N nominally equal outputs; f) N variable phase shifters, each having an input port connected to a respective signal output port of the third signal splitter, a control input port, and a shifted reference signal output port; g) N mixers, each having a low-pass filter, a local oscillator input port connected to the shifted reference signal output port of a respective variable phase shifter, a radio-frequency input port connected to a respective sensor output port, and an intermediate-frequency voltage output port; h) N control feedback circuits, each having an input port connected to the intermediate-frequency voltage output port of one of the mixers, and an output port connected to the control input port of the variable phase shifter whose shifter reference signal output port is connected to the aforementioned mixer, and; i) means for measuring and converting voltages at the control feedback circuit output ports into information about the chemical environment of said chemical sensors.
Claim 65
Dependent Claim
13 words
The apparatus of claim 54, wherein said N chemical sensors comprise surface-acoustic-wave devices.
Claim 66
Dependent Claim
83 words
The apparatus of claim 55, further comprising a reference surface-acoustic-wave device not sensitive to the chemical environment having reference device input and output ports, intercalated in the connection between said second output port of the first signal splitter and said input port of the third signal splitter so that said reference device input port is connected to the second output port of the first signal splitter and said reference device output port is connected to said input port of the third signal splitter.
Claim 67
Dependent Claim
24 words
The apparatus of claim 54, wherein said means for measuring and converting comprise a computer-controlled voltmeter, a signal switching system, and a computer system.
Claim 68
Dependent Claim
20 words
The apparatus of claim 54, wherein said means for measuring and converting comprises N computer-controlled voltmeters and a computer system.
Claim 69
Dependent Claim
16 words
The apparatus of claim 54, wherein said means for measuring and converting comprises a neural net.
Claim 70
Dependent Claim
17 words
The apparatus of claim 54, wherein said means for measuring and converting comprises means for pattern recognition.
Claim 71
Dependent Claim
19 words
The apparatus of claim 54, further comprising a common test case within which said N chemical sensors are housed.
Claim 72
Dependent Claim
14 words
The apparatus of claim 54, wherein said control feedback circuits further comprise gain controls.
Claim 73
Dependent Claim
22 words
The apparatus of claim 62, wherein said gain controls keep the output voltage of each control feedback circuit between nominally ±5 volts.
Claim 74
Dependent Claim
22 words
The apparatus of claim 62, wherein the output voltages of the control feedback circuits are a simple multiple of the chemical concentration.
Claim 75
Dependent Claim
35 words
The apparatus of claim 54, further comprising zeroing means to set the output voltages of the control feedback circuits to zero when said chemical sensors are not exposed to chemicals to which they are sensitive.
Claim 76
Dependent Claim
15 words
The apparatus of claim 54, wherein said means for measuring and converting comprise a voltmeter.
Claim 77
Dependent Claim
17 words
The apparatus of claim 54, wherein said means for measuring and converting comprise a variable-gain measuring device.
Claim 78
Independent Claim
180 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a variable frequency source having a control input port and a radio-frequency output port; b) a splitter, having a splitter input port connected to said output port of the variable frequency source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) a mixer with low-pass filter, having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected to the second splitter output port, and an intermediate-frequency voltage output port; e) a control feedback circuit, having an input port connected to the intermediate-frequency voltage output port of the mixer and an output port connected to the control input port of the variable frequency source, and; f) means for measuring and converting a voltage at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 79
Independent Claim
180 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a variable frequency source having a control input port and a radio-frequency output port; b) a splitter, having a splitter input port connected to said output port of the variable frequency source and a first and a second splitter output port, which divide the splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to the first splitter output port and a sensor output port; d) a mixer with low-pass filter, having a radio-frequency input port connected to the sensor output port, a local oscillator input port connected to the second splitter output port, and an intermediate-frequency voltage output port; e) a control feedback circuit, having an input port connected to the intermediate-frequency voltage output port of the mixer and an output port connected to the control input port of the variable frequency source, and; f) means for measuring and converting a voltage at the control feedback circuit output port into information about the chemical environment of said chemical sensor.
Claim 80
Dependent Claim
13 words
The apparatus of claim 68, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 81
Dependent Claim
20 words
The apparatus of claim 68, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 82
Dependent Claim
25 words
The apparatus of claim 68, further comprising boosting amplifiers to insure adequate signal level at the local oscillator and radio-frequency input ports of the mixer.
Claim 83
Dependent Claim
15 words
The apparatus of claim 68, wherein said control feedback circuit further comprises a gain control.
Claim 84
Dependent Claim
25 words
The apparatus of claim 72, wherein said gain control is set to keep the output voltage of the control feedback circuit between nominally ±5 volts.
Claim 85
Dependent Claim
22 words
The apparatus of claim 72, wherein the output voltage of the control feedback circuit is a simple multiple of the chemical concentration.
Claim 86
Dependent Claim
36 words
The apparatus of claim 68, further comprising zeroing means for setting the output voltage of the control feedback circuit to zero when said chemical sensor is not exposed to chemicals to which the apparatus is sensitive.
Claim 87
Dependent Claim
15 words
The apparatus of claim 68, wherein said means for measuring and converting comprise a voltmeter.
Claim 88
Dependent Claim
18 words
The apparatus of claim 68, wherein said means for measuring and converting comprise a variable-gain voltage measuring device.
Claim 89
Independent Claim
304 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first splitter, having a first splitter input port connected to said output port of the source and a pair of first splitter output ports, which divide a first splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to one of the pair of first splitter output ports and a sensor output port; d) a second splitter, having a second splitter input port connected to said sensor output port and a pair of second splitter output ports, which divide a second splitter input signal into 2 nominally equal outputs; e) a radio-frequency power detector, having a detector input port connected to another of the pair of second splitter output ports and a detector output port providing an attenuation response of the chemical sensor; f) a variable phase shifter, having a reference input port connected to one of the pair of first splitter output ports, a control input port, and a shifted reference output port; g) a mixer with low pass filter having a radio-frequency input port connected to another of the pair of second splitter output ports, a local oscillator input port connected to the shifted reference output port of the variable phase shifter, and an intermediate-frequency voltage output port; h) a control feedback circuit, having an input port connected to the intermediate-frequency voltage output port of the mixer and an output port connected to the control input port of the variable phase shifter to provide a voltage thereto, and; i) means for measuring and converting the voltage at the control feedback circuit output port and the voltage at the radio-frequency power detector output port into information about the chemical environment of said chemical sensor.
Claim 90
Independent Claim
304 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a radio-frequency source having an output port; b) a first splitter, having a first splitter input port connected to said output port of the source and a pair of first splitter output ports, which divide a first splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to one of the pair of first splitter output ports and a sensor output port; d) a second splitter, having a second splitter input port connected to said sensor output port and a pair of second splitter output ports, which divide a second splitter input signal into 2 nominally equal outputs; e) a radio-frequency power detector, having a detector input port connected to another of the pair of second splitter output ports and a detector output port providing an attenuation response of the chemical sensor; f) a variable phase shifter, having a reference input port connected to one of the pair of first splitter output ports, a control input port, and a shifted reference output port; g) a mixer with low pass filter having a radio-frequency input port connected to another of the pair of second splitter output ports, a local oscillator input port connected to the shifted reference output port of the variable phase shifter, and an intermediate-frequency voltage output port; h) a control feedback circuit, having an input port connected to the intermediate-frequency voltage output port of the mixer and an output port connected to the control input port of the variable phase shifter to provide a voltage thereto, and; i) means for measuring and converting the voltage at the control feedback circuit output port and the voltage at the radio-frequency power detector output port into information about the chemical environment of said chemical sensor.
Claim 91
Dependent Claim
13 words
The apparatus of claim 78, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 92
Dependent Claim
20 words
The apparatus of claim 78, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 93
Dependent Claim
15 words
The apparatus of claim 78, wherein said control feedback circuit further comprises a gain control.
Claim 94
Dependent Claim
25 words
The apparatus of claim 81, wherein said gain control is set to keep the output voltage of the control feedback circuit between nominally ±5 volts.
Claim 95
Dependent Claim
22 words
The apparatus of claim 81, wherein the output voltage of the control feedback circuit is a simple multiple of the chemical concentration.
Claim 96
Dependent Claim
35 words
The apparatus of claim 78, further comprising zeroing means for setting the output voltage of the control feedback to zero when said chemical sensor is not exposed to chemicals to which the apparatus is sensitive.
Claim 97
Dependent Claim
15 words
The apparatus of claim 78, wherein said means for measuring and converting comprise a voltmeter.
Claim 98
Dependent Claim
18 words
The apparatus of claim 78, wherein said means for measuring and converting comprise a variable-gain voltage measuring device.
Claim 99
Independent Claim
274 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a variable frequency source having a control input port and a radio-frequency output port; b) a first splitter, having a first splitter input port connected to said output port of the variable frequency source and a pair of first splitter output ports, which divide a first splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to one of the pair of first splitter output ports and a sensor output port; d) a second splitter, having a second splitter input port connected to the sensor output port and a pair of second splitter output ports, which divide a second splitter input signal into 2 nominally equal outputs; e) a radio-frequency power detector, having a detector input port connected to one of the pair of second splitter output ports and a detector output port providing an attenuation response of the chemical sensor; f) a mixer with a low-pass filter, having a radio-frequency input port connected to another of the pair of second splitter output ports, a local oscillator input port connected to another of the pair of first splitter output ports, and an intermediate-frequency voltage output port; g) a control feedback circuit, having an input port connected to the intermediate-frequency voltage output port of the mixer and an output port connected to the control input port of the variable frequency source, and; h) means for measuring and converting the voltage at the control feedback circuit output port and the voltage at the detector output port into information about the chemical environment of said chemical sensor.
Claim 100
Independent Claim
274 words
An apparatus for measuring the chemical environment of chemical sensors, comprising: a) a variable frequency source having a control input port and a radio-frequency output port; b) a first splitter, having a first splitter input port connected to said output port of the variable frequency source and a pair of first splitter output ports, which divide a first splitter input signal into 2 nominally equal outputs; c) a chemical sensor, having a sensor input port connected to one of the pair of first splitter output ports and a sensor output port; d) a second splitter, having a second splitter input port connected to the sensor output port and a pair of second splitter output ports, which divide a second splitter input signal into 2 nominally equal outputs; e) a radio-frequency power detector, having a detector input port connected to one of the pair of second splitter output ports and a detector output port providing an attenuation response of the chemical sensor; f) a mixer with a low-pass filter, having a radio-frequency input port connected to another of the pair of second splitter output ports, a local oscillator input port connected to another of the pair of first splitter output ports, and an intermediate-frequency voltage output port; g) a control feedback circuit, having an input port connected to the intermediate-frequency voltage output port of the mixer and an output port connected to the control input port of the variable frequency source, and; h) means for measuring and converting the voltage at the control feedback circuit output port and the voltage at the detector output port into information about the chemical environment of said chemical sensor.
Claim 101
Dependent Claim
13 words
The apparatus of claim 87, wherein said chemical sensor comprises a surface-acoustic-wave device.
Claim 102
Dependent Claim
20 words
The apparatus of claim 87, wherein said means for measuring and converting comprise a computer-controlled voltmeter and a computer system.
Claim 103
Dependent Claim
15 words
The apparatus of claim 87, wherein said control feedback circuit further comprises a gain control.
Claim 104
Dependent Claim
25 words
The apparatus of claim 90, wherein said gain control is set to keep the output voltage of the control feedback circuit between nominally ±5 volts.
Claim 105
Dependent Claim
22 words
The apparatus of claim 90 wherein the output voltage of the control feedback circuit is a simple multiple of the chemical concentration.
Claim 106
Dependent Claim
36 words
The apparatus of claim 90, further comprising zeroing means for setting the output voltage of the control feedback circuit to zero when said chemical sensor is not exposed to chemicals to which the apparatus is sensitive.
Claim 107
Dependent Claim
15 words
The apparatus of claim 87, wherein said means for measuring and converting comprise a voltmeter.
Claim 108
Dependent Claim
18 words
The apparatus of claim 87, wherein said means for measuring and converting comprise a variable-gain voltage measuring device.
Claim 109
Independent Claim
90 words
An apparatus for measuring the chemical environment of at least one chemical sensor, comprising: a) a source connected to an input port of each sensor for activation thereof at a radio frequency; and b) detection means, including an in-phase and quadrature-phase demodulator, connected to the source and to an output port of each chemical sensor for providing a pair of output voltages with each output voltage being proportional to a difference in phase between the input and output ports of each chemical sensor for determining information about the chemical environment.
Claim 110
Independent Claim
90 words
An apparatus for measuring the chemical environment of at least one chemical sensor, comprising: a) a source connected to an input port of each sensor for activation thereof at a radio frequency; and b) detection means, including an in-phase and quadrature-phase demodulator, connected to the source and to an output port of each chemical sensor for providing a pair of output voltages with each output voltage being proportional to a difference in phase between the input and output ports of each chemical sensor for determining information about the chemical environment.
Claim 111
Dependent Claim
13 words
The apparatus of claim 96, wherein each chemical sensor is a surface-acoustic-wave sensor.
Claim 112
Dependent Claim
29 words
The apparatus of claim 96, wherein the detection means further includes amplifier means connected to at least one input of the demodulator for insuring an adequate signal level thereat.
Claim 113
Dependent Claim
23 words
The apparatus of claim 96, wherein the detection means further includes feedback means for providing a substantially constant quadrature-phase signal from the demodulator.
Claim 114
Dependent Claim
24 words
The apparatus of claim 96, further comprising a reference sensor isolated from the chemical environment and providing a reference signal to the detection means.
Claim 115
Dependent Claim
30 words
The apparatus of claim 96, wherein each output voltage is further proportional to a product of amplitudes of a local oscillator input and a radio-frequency input provided to the demodulator.
Claim 116
Dependent Claim
21 words
The apparatus of claim 96, further comprising computing means for extracting phase and amplitude shifts from the pair of output voltages.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-06-08 | 2001-12-08 | 2002-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-06-08 | 2005-12-08 | 2006-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-06-08 | 2009-12-08 | 2010-06-09 | $7700.00 | Window Closed / Lapsed |