TEMPERATURE COMPENSATED DIELECTRIC CHARACTERIZATION OF SUBSTANCES

• US 20160313259A1
• Filed: 04/20/2016
• Published: 10/27/2016
• Est. Priority Date: 04/20/2015
• Status: Abandoned Application

• Current Assignee: Vayyar Imaging Ltd.
• Original Assignee: Vayyar Imaging Ltd.
• Inventors: SHAYOVITZ, Shachar
• Application Number:
  US15/133,333
• Publication Number:
  US 20160313259A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 22/00 Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more G01N3/00 - G01N17/00, G01N24/00 take precedence
• CPC Class Codes: G01N 33/06 Determining fat content, e.g. by butyrometer
• CPC Class Codes: G01R 27/2623 Measuring-systems or electronic circuits G01R27/2635, G01R27/2682 take precedence

Abstract

A system device and methods for temperature compensation for RF systems and devices such as devices for dielectric characterizing of one or more substances where the substances have temperature-dependent behavior. The system comprises RF sensors and a processor for analyzing the substances according to impedance or dielectric properties measures of the substances.

Claims

1. A system for characterizing a substance, said system comprising:

a housing body having a cavity therein wherein said cavity is configured to contain said substance;

a transmit unit configured to transmit a plurality of Radio Frequency (RF) signals towards said substance;

at least one electromagnetic sensor, wherein said at least one electromagnetic sensor is configured to receive RF signals affected by said substance and provide RF responses data of said substance;

a Radio Frequency Signals Measurement Unit (RFSMU) configured to receive said RF responses data and measure said RF responses data;

a temperature sensor configured to measure the temperatures of said substance over time; and

at least one processing unit, said at least one processing unit is configured to;

retrieve temperature dependent RF response model of said substance;

receive the temperatures and the measured RF responses data of said substance;

normalize the measured RF responses of said substance according to said temperature dependent RF response model to generate compensated measured RF responses of said substance at a reference temperature; and

process said compensated measured RF responses to identify the characteristics of said substance.

2. The system of claim 1 wherein said characteristics are dielectric properties of said substance.

3. The system of claim 1 wherein said temperature dependent RF response model is configured by measuring said RF responses data for several values of temperatures and fitting said model.

4. The system of claim 1 wherein said substance is a mixture of materials and the characteristics are percentage values of the mixture of materials.

5. The system of claim 1 wherein the identification of characteristics of said substance is performed using a model generated by measuring said compensated RF responses for several values of said characteristics and fitting said model.

6. The system of claim 1 wherein the temperatures are obtained by the at least one electromagnetic sensor.

7. The system of claim 1 wherein said at least one electromagnetic sensor comprises at least two antennas and wherein said at least one processing unit is configured to analyze a passage of energy transmitted from at least one of said antennas to at least one other antenna.

8. The system of claim 1 wherein said at least one electromagnetic sensor is a capacitive sensor and wherein said sensor is configured to spatially resolve the dielectric properties of the said substance.

9. The system of claim 1 wherein said substance is in the form selected from a group consisting of:

liquid, paste, gas, granular material.

10. The system of claim 9 wherein said liquid is selected from the group consisting of:

oil, milk, ink, water, bodily fluids, liquid mixture.

11. The system of claim 2 wherein the dielectric properties of the substance are configured based on an estimation model, said estimation model is based on measuring RF signals affected by plurality of substances, wherein said plurality of substances parameters are known.

12. A method for characterizing a substance, carried out using at least one electronic processor unit, the method comprising:

transmitting a plurality of Radio Frequency (RF) signals from a transmit unit towards said substance;

receiving said transmitted RF signals by at least one electromagnetic sensor;

providing RF responses data of said substance by said at least one electromagnetic sensor based on said plurality of RF signals;

obtaining the plurality RF signals by a Radio Frequency Signal Measurement Unit (RFSMU);

measuring the obtained RF signals by the RFSMU;

measuring the temperatures of said substance over time to yield temperature data of said substance;

retrieving a temperature dependent RF response model of said substance by at least one processing unit;

normalizing the RF responses data of said substance according to said temperature dependent RF response model;

generating compensated RF responses of said substance at a reference temperature; and

processing said compensated RF responses to identify the characteristics of said substance.

13. The method of claim 12 wherein said characteristics are dielectric properties of said substance.

14. The method of claim 12 wherein said temperature dependent RF response model is configured by measuring said RF responses data for several values of temperature and fitting said model.

15. The method of claim 12 wherein said substance is a mixture of materials and the characteristics are a percentage values of the materials.

16. The method of claim 12 wherein the identification of characteristics of said substance is performed using a model generated by measuring said compensated RF responses for several values of said characteristics and fitting said model.

17. The method of claim 12 wherein the temperatures are obtained by the at least one electromagnetic sensor.

18. The method of claim 12 wherein said at least one electromagnetic sensor comprises at least two antennas and wherein said processor is configured to analyze a passage of energy transmitted from at least one of said antennas to at least one other antenna.

19. The method of claim 12 wherein said at least one electromagnetic sensor is a capacitive sensor and wherein said capacitive sensor is configured to spatially resolve the dielectric properties of the said substance.

20. The method of claim 12 wherein said temperature dependent RF response model comprises temperature dependence parameters, frequency dependence functions and temperature dependence functions where the temperature dependent RF response model parameters are a₀ till a_k, b₀ till b_k, c₀ till c_k and d₀ till d_k and

Δ

T=(T₁−

T₀)

<

H_T1(f)=<

H_T0(f)+(c_kΔ

T^k'"'"'11+ . . . +c₀)(a_nfⁿ+a<sub>n−

1</sub>f<sup>n−

1</sup>+ . . . +a₁f+a₀)

20log₁₀|H_T1(f)|=20log|H_T0(f)|+(d_rΔ

T_r+<sub>r−

1</sub>Δ

T<sup>r−

1</sup>+ . . . +d₀)(b_mf^m+b<sub>m−

1</sub>f<sup>m−

1</sup>+ . . . +b₁f+b₀)

Where T₁ and T₀ are the temperatures for the frequency responses H_T1(f) and H_T0(f).