NL1039732C2 - Method and device for measuring dielectric properties of a fluid and suppressing wave reflections. - Google Patents

Method and device for measuring dielectric properties of a fluid and suppressing wave reflections. Download PDF

Info

Publication number
NL1039732C2
NL1039732C2 NL1039732A NL1039732A NL1039732C2 NL 1039732 C2 NL1039732 C2 NL 1039732C2 NL 1039732 A NL1039732 A NL 1039732A NL 1039732 A NL1039732 A NL 1039732A NL 1039732 C2 NL1039732 C2 NL 1039732C2
Authority
NL
Netherlands
Prior art keywords
pcb
document
fluid
resonator
definition
Prior art date
Application number
NL1039732A
Other languages
Dutch (nl)
Inventor
Natalia Hoog
Mateo Jozef Jacques Mayer
Original Assignee
Stichting Wetsus Ct Excellence Sustainable Water Technology
Smart Frequencies B V
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Stichting Wetsus Ct Excellence Sustainable Water Technology, Smart Frequencies B V filed Critical Stichting Wetsus Ct Excellence Sustainable Water Technology
Priority to NL1039732A priority Critical patent/NL1039732C2/en
Priority to NL1040124A priority patent/NL1040124C2/en
Application granted granted Critical
Publication of NL1039732C2 publication Critical patent/NL1039732C2/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N22/00—Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/18—Water
    • G01N33/1826—Organic contamination in water

Landscapes

  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Pathology (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Medicinal Chemistry (AREA)
  • Food Science & Technology (AREA)
  • Engineering & Computer Science (AREA)
  • Electromagnetism (AREA)
  • Measurement Of Resistance Or Impedance (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Description

Method and device for measuring dielectric properties of a fluid and suppressing wave reflections
The present invention relates to a method and device for measuring the dielectric properties of a fluid comprising a multi layer printed circuit board (PCB), at least a first 5 stripline resonator printed on the PCB such that the conductors, that form the resonator, are embedded completely in the PCB dielectric, at least a first transmission line connector on the PCB, connecting a first function generator to the PCB, at least a second transmission line connector on the PCB, connecting a first spectrum analyzer and / or a first rectifier to the PCB, at least a first transmission stripline, connecting the first transmission line 10 connector on the PCB to the first stripline resonator, at least a second transmission
stripline, connecting the second transmission line connector on the PCB to the first stripline J
resonator, at least one hole and preferably more holes in the PCB whereby these holes are positioned on the PCB and at least partially form the dielectric (determining the properties ' of) the first resonator. The PCB is placed in a fluid under investigation such that at least IS part of the holes in the PCB are filled with the fluid under investigation.
introduction
The present invention relates to a method and device for inline measurement of the properties of a fluïdum, without the use of chemicals, using the physical principles of 20 transmission line technology. More specifically, the present invention relates to a method and device to measure the dielectric properties of fluids, fluid - solid suspensions, fluid -gas suspensions and solid - gas suspensions. Even more specifically, the present invention relates to a method and device to assess the properties of water, such as drinking water, waste water and industrial process water.
25 Many prior art methods to determine the quality of drinking water, process water and industrial water are labor intensive, require the use of chemicals for chemical and / or biological analysis and are offline. As a result, many prior art water analysis techniques are expensive and introduce a time delay before measurement information is available.
A promising technique to track changes in the quality of a water stream is to asses its 30 dielectric properties. Existing prior art methods to measure the dielectric properties of a solution are based on classic capacitance measurements in discrete elements such as a plate capacitor. These methods are offline and suffer from relatively large parasitic capacitance and / or parasitic inductance, thereby limiting the sensitivity of the measurements, and / or require a relatively complex measurement set-up, involving 35 relatively high investment cost. A recently developed technique for inline measurement of the dielectric properties of fluids is based on transmission line technologie. A fluid sample is applied as dielectric in a transmission line resonator, such as a coaxial stub resonator or a 1039732 2 stripline resonator. Subsequently, the electric properties of the transmission line resonator, further on referred to as stub resonator, are characterized by an amplitude versus frequency plot, further on referred to as A-f plot. The shape of the A-f plot is determined by the dielectric properties of the fluid under investigation. By the use of transmission line 5 theory i.e., by solving the telegrapher's equations, the dielectric properties of a fluid i.e, its dielectric permittivity and loss tangent as a function of frequency, can be derived directly from the A-f plot. More qualitatively, an A-f plot provides a fingerprint of the fluid and can be used to track changes of the fluid composition and to use these changes in an early warning system.
10 In this document, a stub resonator is defined as a resonator based on any type of transmission line such as, but not limited to, a coaxial transmission line resonator, a stripline or any combination of striplines and / or coaxial transmission line resonators.
In this document, a stripline is defined as any type of transmission line or transmission line resonator present on a PCB.
15 The sensitivity and reliability of a sensor based on a transmission line resonator is not only determined by the design of the stub resonator but also to a large extent by the electric connections of the stub resonator to the transmission lines of the measurement set-up.
The technology according to the present invention deals with a unique combination of stub resonator design and electrical interface connections from the stub resonator to the 20 transmission lines of the measurement set-up, further on referred to as "matched sensor system". The matched sensor system according to the present invention provides a very sensitive and reliable device to assess the dielectric properties of a fluïdum. Additionally, the matched sensor system can be produced in a reproducible and cost effective way.
25 Description of the technology according to the present invention
According to a first aspect, the present invention relates to a function generator FG. This function generator preferably produces a sinus or square wave electrical signal with a frequency that can be adjusted in the range between 1 Hz and 50 GHz.
According to a second aspect, the present invention relates to a spectrum analyzer or a hf 30 (high frequency) rectifier SA, preferably able to measure the amplitude of a sinus or square wave electrical signal with a frequency in the range between 1 Hz and 50 GHz.
According to a third aspect, the present invention relates to a first transmission line that is connected to the function generator FG.
According to a fourth aspect, the present invention relates to a second transmission line 35 that is connected to the spectrum analyzer SA.
According to a fifth aspect, the present invention relates to a printed circuit board (PCB). According to a sixth aspect, the present invention relates to a first transmission line 3 connector, connecting the first transmission line to the PCB.
According to a seventh aspect, the present invention relates to a second transmission line connector, connecting the second transmission line to the PCB.
According to an eighth aspect, the present invention relates to a stub resonator according 5 to definition in this document, that is printed on the PCB.
According to a nineth aspect, the present invention relates to a first electrical interface connection E1, connecting the stub resonator to the first transmission line interface on the PCB. Interface E1 is a transmission line printed on the PCB with a characteristic impedance that preferably varies with the length coordinate of the transmission line thereby 10 matching the characteristic impedance of the transmission line from the function generator EG to the characteristic impedance of the stub resonator.
According to a tenth aspect, the present invention relates to a second electrical interface connection E2, connecting the stub resonator to the second transmission line interface on the PCB. Interface E2 is a transmission line printed on the PCB with a characteristic 15 impedance that preferably varies with the length coordinate of the transmission line thereby matching the characteristic impedance of the transmission line from the spectrum analyzer SA to the characteristic impedance of the stub resonator.
According to an eleventh aspect, the present invention relates to at least one hole and preferably more holes in the PCB. The holes are unplated (no metal coating on the "walls of 20 the holes") and positioned in the active part of the stub resonator i.e., such that at least part of the holes make part of the dielectric determining the electrical properties of the stub resonator. Preferably, the dielectric under investigation is at least partly present in the holes and consists for more than 10 percent by volume of a fluid.
Figure 1 gives a schematic overview of the technology according to the present invention.
25 The numbers in figure 1 relate to the following elements that were previously described in aspects one to eleven: 1. Function generator F1 2. First transmission line 3. First transmission line connector 30 4. First electrical interface connector E1 5. Stub resonator 6. Second electrical interface connector E2 7. Second transmission line connector 8. Second transmission line
35 9. Spectrum analyzer SA
10. Hole in the PCB dielectric
The main aspects of the present invention have now been described. In the following, the 4 aspects of the present invention will be further detailed. Also a number of preferred embodiments of the present invention will be explained.
Preferably, the function generator FG (#1 in figure 1) and the spectrum analyzer SA (#9 in figure 1) have an internal resistance of 50 Ohm. The characteristic impedance of the first 5 transmission line (#2 in figure 1) and the second transmission line (#8 in figure 1) preferably amounts 50 Ohm. Connectors E1 (#3 in figure 1) and E2 (#7 in figure 1) preferably have a characteristic impedance of 50 Ohm. The stub resonator (#5 in figure 1) preferably has a characteristic impedance of 50 Ohm. However, it is noted that the characteristic impedance of the stub resonator depends on the dielectric present in the holes in the active part of the 10 PCB (#10 in figure 1). Therefor, it will depend on the dielectric present in the holes, whether or not the stub resonator is matched to the rest of the measuring set-up. Additionally, it is noted that, from a construction point of view, it may be feasible to design a stub resonator with a characteristic impedance that is considerably different from that of the function generator FG, spectrum analyzer SA, transmission lines and connectors.
15 Now the technology according to the present invention has been explained, a number of additional remarks with respect to figure 1 are made. The hole (#10) in figure 1 can be placed at different positions in the dielectric of the stripline, for example at position 5. Preferably, multiple holes are made in the resonator. The solid line (wire) cut in 2 pieces by hole 10, preferably has exactly the same length as both parallel wires in figure 1. Hole 10 is 20 preferably placed between the solid line and one of both parallel wires without damaging any wire. Hole 10 can be plated as shown in figure 2. Also a ground plane can be applied on the backside of the PCB as shown in figure 3, whereby the hole in the PCB is not metal plated. Finally a ground plane can be applied on the backside of the PCB as shown in figure 4, whereby also the hole in the PCB is metal plated. Plating of the holes can be 25 interesting in case the sensor is applied as a corrosion sensor. In case the plated holes corrode, the A-f plot will change.
Example 1
Consider a measurement system with a function generator FG and spectrum analyzer SA, both with an internal resistance of 50 Ohm. The first and second transmission lines as well 30 as the first and second transmission line connectors have a characteristic impedance of 50 Ohm. The stub resonator has, from a construction point of view, a characteristic impedance of 20 Ohm. In case the first electrical interface connection E1 and the second electrical interface connection E2 would be transmission lines with a characteristic impedance of 50 Ohm as well, radio waves would be reflected at the connection points of E1 and E2 with the 35 stub resonator. This would result in a considerable decrease of the sensitivity of the measurement system. Additionally, it would be very difficult to predict the behavior of the measurement system as a function of frequency so that interpretation of A-f plots becomes 5 difficult. To overcome reflections at the connection point of the stub resonator, electrical interface connections E1 and E2 are designed such that their characteristic impedance is a function of their length coordinate. In this example, interface connection E1 has a characteristic impedance of 50 Ohm at the first transmission line connector. Going from the 5 first transmission line connector to the stub resonator, the characteristic impedance of the interface connection E1 gradually decreases from 50 Ohm to 20 Ohm at the stub resonator. Analogously, the characteristic impedance of E2 gradually increases from 20 Ohm to 50 Ohm going from the stub resonator to the second transmission line connector.
The gradual change of characteristic impedance of E1 and E2 as a function of its length 10 coordinate is realized by changing the geometrical shape of the striplines as a function of their length coordinate using transmission line theory.
Surprisingly, it was found that a measuring system according to the present invention is very stable and insensitive to reflection even if the characteristic impedance of E1 and E2 near the stub resonator is NOT exactly matched to the characteristic impedance of the stub 15 resonator. This is further explained in example 2.
Example 2.
Consider the same measurement system as in example 1. However, in example 2, the characteristic impedance of E1, going from the first transmission line connector to the stub resonator, gradually decreases from 50 Ohm to 30 Ohm at the stub resonator (and not to 20 20 Ohm as in example 1). Analogously, the characteristic impedance of E2 gradually increases from 30 Ohm to 50 Ohm going from the stub resonator to the second transmission line connector. Since the stub resonator has a characteristic impedance of 20 Ohm, there is an impedance mismatch of 10 Ohm at the connection point of E1 and E2 to the stub resonator. In spite of this impedance mismatch, the effect of wave reflections on 25 the accuracy and reliability of the measurement set-up appears to be very limited. Although E1 and E2 only provide limited impedance matching, the presence of E1 and E2 appears to be a very effective measure to avoid undesired wave reflections. In fact, limited impedance matching through E1 and E2 has a surprisingly stabilizing effect on the performance of the measurement set-up at different conditions. It is noted that, possibly also the direct 30 connection of the stub resonator to E1 and E2 i.e., through PCB wires instead of connectors with a finite length, contributes considerably to the reduction of wave reflections.
After the explanation in examples 1 and 2, a number of preferred embodiments will now be elucidated.
35 In a first preferred embodiment of the present invention, the function generator is software configurable by the use of a first microcontroller such as a PIC16F88. The spectrum analyzer preferably consists of a rectifier using a germanium type diode. The rectified 6 signal is connected to an analog to digital converter of the first microcontroller. Since the frequency of the signal is already known (because it is software configurable), the A-f plot can be generated automatically and communicated and stored onto an external device. Also an alarm can be generated automatically if the A-f plot deviates from a pre-defined 5 reference plot.
In a second preferred embodiment of the present invention, the transmission lines on the PCB, including the stub resonator, consist of a discrete wire placed at a fixed distance over a ground plane. In this document, a wire is defined as a metal containing conductor shaped as a cilinder, a rectangular cuboid, a cuboid or any other 3D shape that may act as an 10 electrical conductor. In this document, a ground plane is defined as any metal containing plane that may act as a conductor and / or shield for electromagnetic waves. In this document, the characteristic dimensions of a cilindrical wire are defined as the diameter of the wire and the length of the wire. In this document, the characteristic dimensions of a rectangular cuboid as defined as the length of the cuboid, the width of the cuboid and the 15 height of the cuboid. In this document, the characteristic dimensions of any other wire are defined as the value of the minimum number of mathematic parameters that are required to exactly define the dimensions of that wire. In this document, the characteristic dimensions of the ground plane are defined as the length of the ground plane and the width of the * ground plane in case the ground plane is a rectangle. The characteristic dimensions of any 20 other ground plane than a rectangular ground plane are defined as the value of the minimum amount of mathematical parameters that are required to define the exact shape of the ground plane.
In a third preferred embodiment of the present invention, the transmission lines on the PCB, including the stub resonator, consist of a first discrete wire placed at a fixed distance 25 from 2 parallel wires such that the first discrete wire is present between the other 2 wires. Preferably, the 3 wires are present in the same plane. It is noted that also so called "off center" transmission lines in which the first discrete wire is not placed exactly in the center between the other 2 discrete wires make part of the present invention.
In a fourth preferred embodiment of the present invention, the transmission lines on the 30 PCB, including the stub resonator, consist of 2 discrete parallel wires. Preferably, the 2 parallel wires are present in the same plane.
In a fifth preferred embodiment of the present invention, the transmission lines on the PCB are not all based on the same geometrical design principles but each of them on any (combinations) of the designs described in the second, third and fourth preferred 35 embodiment.
In a sixth preferred embodiment of the present invention a multilayer PCB is applied in which all transmission lines are positioned inside the dielectric of the PCB. In the dielectric 7 that is determining the properties of the stub resonator, holes are made. These holes are filled with the dielectric under investigation, for example by placing the PCB in the fluid under investigation. The holes are positioned in the PCB such that they do not damage any of the stripline conductors. As a result, the E1, E2 and the stub resonator are completely 5 isolated from the fluid under investigation even though the PCB is placed in this fluid. As a result, a very stable and reliable measuring system is obtained.
In a seventh preferred embodiment of the present invention, the configuration described in the sixth embodiment is combined with any of the preferred embodiments one to six.
In an eighth preferred embodiment of the present invention, the holes in the PCB are filled 10 with a growth medium for bacteria such as a polymer or a gel. In case bacterial growth occurs, the dielectric properties of the polymer of gel will change which will result in a change in the A-f plot. Hence a sensor for detection of bacterial growth is obtained. It is noted that this principle is also applicable for detection of chemical compounds in case an adsorbent for these compounds is immobilized in the holes.
15 In a nineth preferred embodiment of the present invention, any of the preferred embodiments one to eight is combined with a selection of any other of the preferred embodiments one to eight.
In a tenth preferred embodiment, any of the wires in the stub resonator according to the definition in this document, is characterized by discontinuities, see also figure 5. The wire in 20 figure 5 consists of conductive elements such as element number 2, and non conductive discontinuities between those conductive elements. The discontinuities in the wire in figure 5, will, amongst others, result in a higher sensitivity of the stub resonator for small changes in conductivity of the dielectric under investigation. Also, additional conductive elements and other conductive geometrical planes can be printed on the PCB in the vicinity of the 25 stub resonator, see figure 6. The geometrical planes may have any shape and have a resonant frequency that depends their shape and on the dielectric in which they are present. Hence, geometrical planes in the vicinity of a stub resonator may be helpful tools to increase the sensitivity of the sensor according to the technology of the present invention in a desired frequency range. Also, geometrical planes on the PCB can be used as an 30 impedance transformer for matching characteristic impedance of stub resonators and that of transmission line connectors, the function generator and the spectrum analyzer or rectifier.
Now the features of the technology according to the present invention have been explained, the unique features of the invention are summarized: 35 1. The measuring system is very stable and sensitive because of • Impedance matching through E1, E2, and the absence of additional connectors between E1 and the stub resonator and E2 and the stub 8 resonator.
• The absence of contact between the stripline and stub resonator conductors and the fluid under investigation • The presence of well defined unplated holes in the active part of the stub 5 resonator in which the dielectric under investigation is placed.
2. The measuring system is based on PCB technology and can be produced in a very reliable and cost effective way.
Non limiting examples of a fluïdum feasible to be investigated with the technology according to the present invention are drinking water, waste water, food.
10 15 20 25 30 35 9
Clauses 1. Sensor for measuring the dielectric properties of a fluidum consisting for more than 10 percent by volume of a fluid characterized by • a function generator connected to 5 · a first transmission line which is connected to a • first transmission line connector that is mounted on a • first printed circuit board (PCB), • a first electrical interface connection, connected on one end to the first transmission line connector, and consisting of a stripline on the PCB of which 10 the characteristic impedance changes at least 5% over its total length whereby said first electrical interface connection is connected on its other end to a • first stub resonator according to the definition in this document, consisting of a stripline on the PCB,
15 «at least one unplated hole in first stub resonator dielectric on the PCB
• a fluidum sample under investigation placed at least partly in at least one unplated hole in the first stub resonator dielectric on the PCB
• a second electrical interface connection, connected on one end to the first stub resonator and consisting of a stripline on the PCB of which the 20 characteristic impedance changes at least 5% over its total length whereby said second electrical interface connection is connected on its other end to • a second transmission line connector that is mounted on the first PCB and connected to a • second transmissione line connected to a 25 · spectrum analyzer or a rectifier, SA, for measuring the amplitude of the electrical signal transmitted from function generator FG through the measuring system to the spectrum analyzer or rectifier SA.
• at least one microcontroller connected to the function generator and to the spectrum analyzer or rectifier, equipped with software for automated 30 measurement of A-f plots.
2. Sensor according to clause 1 whereby the first and second electrical interface connections consist of a discrete wire according to the definition in this document, placed at a fixed distance above a ground plane according to the definition in this document, whereby any of the characteristic dimensions of the discrete wire either 35 increase or decrease as a function of the length coordinate of the discrete wire, characterized by either an increase or decrease of more than 1% over the total length of the wire.
10 3. Sensor according to any of the previous clauses 1 or 2 whereby the first and second electrical interface connections consist of a discrete wire according to the definitions in this document, placed at a fixed distance above a ground plane according to the definition in this document, whereby any of the characteristic dimensions of the 5 ground plane either increase or decrease by more than 1% going from one end of the wire above the ground plane to the other end of the wire above the ground plane.
4. Sensor according to one of the previous clauses 1 to 3 whereby the stub resonator according to the definition in this document, consists of a discrete wire according to 10 the definition in this document, placed at a fixed distance above a ground plane according to the definition in this document, whereby any of the characteristic dimensions of the discrete wire either increase or decrease as a function of the length coordinate of the discrete wire, characterized by either an increase or decrease of more than 1% over the total length of the wire.
15 5. Sensor according to one of the previous clauses 1 to 3 whereby the stub resonator according to the definition in this document, consists of a discrete wire according to the definitions in this document, placed at a fixed distance above a ground plane according to the definition in this document whereby any of the characteristic dimensions of the ground plane either increase or decrease by more than 1% going 20 from one end of the wire above the ground plane to the other end of the wire above the ground plane.
6. Sensor according to one of the previous clauses 1 to 5 whereby any of the characteristic parameters of a discrete wire, according to the definition in this document, that is part of either the first electrical interface connection or the second 25 electrical interface connection or the stub resonator, changes more than 1% going from one end of the wire to the other end of the wire.
7. Sensor according to one of the previous clauses 1 to 6 whereby the PCB is a multilayer PCB in which the striplines, including the stub resonator according to the definition in this document, are embedded completely so that there is no direct 30 contact between the conductors of wich the striplines are composed on one hand and the dielectric under investigation on the other hand.
8. Sensor according to one of the previous clauses 1 to 7 whereby not only the holes in the PCB are at least filled partly with the fluïdum under investigation but also at least part of the PCB itself is placed in the fluidum under investigation.
35 9. Method for measuring the dielectric properties of a fluidum consisting for more than 10 percent by volume of a fluid characterized by a sensor according to one of the previous clauses 1 to 8.
1039732

Claims (12)

1. Sensor voor het meten van de dielectrische eigenschappen van een fluidum dat voor meer dan 10 volumeprocenten uit vloeistof bestaat gekenmerkt door • een functiegenerator werkzaam verbonden met 5. een eerste transmissielijn die werkzaam is verbonden met een • eerste transmissielijnconnector die is gemonteerd op een • eerste printplaat (PCB), • een eerste elektrische interface verbinding, waarvan epn uiteinde werkzaam is verbonden met de eerste transmissielijnconnector, bestaande uit een 10 stripline op de PCB waarvan de karakteristieke impedantie tenminste 5% verandert over de totale lengte van deze eerste elektrische interface verbinding en waarbij het andere uiteinde van deze eerste elektrische interface verbinding werkzaam verbonden is met • een eerste resonator bestaande uit een stripline, volgens de definitie in dit 15 document, op de PCB • tenminste een, aan de randen niet gemetalliseerd, gat in het dielectricum van de eerste resonator • een monster van het te onderzoeken fluidum dat zich tenminste gedeeltelijk in tenminste een, aan de randen niet gemetalliseerd, gat in het dielectricum 20 van de resonator bevindt • een tweede elektrische interface verbinding, waarvan een uiteinde werkzaam is verbonden met de eerste resonator, bestaande uit een stripline op de PCB waarvan de karakteristieke impedantie tenminste 5% verandert over de totale lengte van deze tweede elektrische interface verbinding en 25 waarbij het andere uiteinde van deze tweede elektrische interface verbinding werkzaam verbonden is met • een tweede elektrische interface connector die op de eerste PCB is gemonteerd en die werkzaam is verbonden met • een tweede transmissielijn die werkzaam is verbonden met 30. een spectrumanalyzer of een gelijkrichter SA, voor meting van de amplitude van het elektrisch signaal dat door de functiegenerator via het meetsysteem naar de spectrumanalyzer of gelijkrichter SA wordt overgebracht • tenminste een microcontroller die werkzaam is verbonden met de functiegenerator en de spectrumanalyzer of gelijkrichter en die is voorzien 35 van software om automatisch amplitude versus frequentie grafieken (A-f plots) te kunnen meten. 1039732A sensor for measuring the dielectric properties of a fluid consisting of fluid for more than 10 volume percentages characterized by • a function generator operatively connected to 5. a first transmission line operatively connected to a • first transmission line connector mounted on a • first printed circuit board (PCB), • a first electrical interface connection, one end of which is operatively connected to the first transmission line connector, consisting of a stripline on the PCB whose characteristic impedance changes at least 5% over the total length of this first electrical interface connection and wherein the other end of this first electrical interface connection is operatively connected to • a first resonator consisting of a stripline, according to the definition in this document, on the PCB • at least one hole, not metallized at the edges, in the dielectric of the first resonator • a sample of it too on the fluid that is at least partially in at least one hole, not metallized at the edges, in the dielectric 20 of the resonator; a second electrical interface connection, one end of which is operatively connected to the first resonator, consisting of a stripline on the PCB of which the characteristic impedance changes at least 5% over the total length of this second electrical interface connection and wherein the other end of this second electrical interface connection is operatively connected to a second electrical interface connector mounted on the first PCB and which is operatively is connected to • a second transmission line operatively connected to 30. a spectrum analyzer or a rectifier SA, for measuring the amplitude of the electrical signal transmitted by the function generator via the measuring system to the spectrum analyzer or rectifier SA • at least one microcontroller that is working verb with the function generator and the spectrum analyzer or rectifier and which is provided with software to be able to automatically measure amplitude versus frequency graphs (A-f plots). 1039732 2. Sensor volgens conclusie 1 waarbij de eerste en tweede elektrische interface verbindingen elk uit een discrete draad, volgens de definitie in dit document, bestaan, die op een vaste afstand boven een grondvlak, volgens de definitie in dit document, is geplaatst, waarbij enige karakteristieke dimensie van de discrete 5 draad, niet zijnde de lengte van de draad, meer dan 1% toeneemt of afneemt over de totale lengte van de betreffende discrete draad.Sensor according to claim 1, wherein the first and second electrical interface connections each consist of a discrete wire, according to the definition in this document, which is placed at a fixed distance above a ground plane, according to the definition in this document, wherein some characteristic dimension of the discrete thread, not being the length of the thread, increases or decreases by more than 1% over the total length of the discrete thread in question. 3. Sensor volgens een van de voorgaande conclusies 1 of 2 waarbij de eerste en tweede elektrische interface verbindingen elk uit een discrete draad, volgens de definitie in dit document, bestaan, die op een vaste afstand boven een grondvlak, 10 volgens de definitie in dit document, is geplaatst, waarbij enige karakteristieke dimensie van het betreffende grondvlak meer dan 1% toeneemt of afneemt over de totale lengte van de betreffende discrete draad.3. Sensor as claimed in any of the foregoing claims 1 or 2, wherein the first and second electrical interface connections each consist of a discrete wire, according to the definition in this document, which at a fixed distance above a ground plane, according to the definition in this document document, where any characteristic dimension of the relevant base plane increases or decreases by more than 1% over the total length of the discrete wire in question. 4. Sensor volgens een van de voorgaande conclusies 1 t/m 3 waarbij de eerste resonator uit een discrete draad, volgens de definitie in dit document, bestaat, die j IS op een vaste afstand boven een grondvlak, volgens de definitie in dit document, is geplaatst, waarbij enige karakteristieke dimensie van de discrete draad, niet zijnde de lengte van de draad, meer dan 1% toeneemt of afneemt over de totale lengte van de betreffende discrete draad.Sensor according to one of the preceding claims 1 to 3, wherein the first resonator consists of a discrete wire, according to the definition in this document, which is at a fixed distance above a ground plane, according to the definition in this document, is placed in which any characteristic dimension of the discrete thread, not being the length of the thread, increases or decreases by more than 1% over the total length of the discrete thread in question. 5. Sensor volgens een van de voorgaande conclusies 1 t/m 3 waarbij de eerste 20 resonator uit een discrete draad, volgens de definitie in dit document, bestaat, die op een vaste afstand boven een grondvlak, volgens de definitie in dit document, is geplaatst, waarbij enige karakteristieke dimensie van het betreffende grondvlak meer dan 1% toeneemt of afneemt over de totale lengte van de discrete draad.5. Sensor as claimed in any of the foregoing claims 1-3, wherein the first resonator consists of a discrete wire, according to the definition in this document, which is at a fixed distance above a ground plane, according to the definition in this document. where any characteristic dimension of the respective base plane increases or decreases by more than 1% over the total length of the discrete wire. 6. Sensor volgens een van de voorgaande conclusies 1 t/m 5 waarbij enige 25 karakteristieke dimensie, niet zijnde de lengte, van een discrete draad, volgens de definitie in dit document, op de PCB meer dan 1% verandert over de totale lengte van die betreffende discrete draad.6. Sensor as claimed in any of the foregoing claims 1-5, wherein any characteristic dimension, not being the length, of a discrete wire, according to the definition in this document, on the PCB changes more than 1% over the total length of those concerning discrete thread. 7. Sensor volgens een van de voorgaande conclusies 1 t/m 6 waarbij de PCB uit verschillende lagen is opgebouwd en waarbij de striplines, inclusief de eerste 30 resonator, zich binnenin de PCB bevinden zodat er geen direct contact is tussen de geleiders waaruit de striplines zijn opgebouwd en het te onderzoeken fluïdum.7. Sensor as claimed in any of the foregoing claims 1-6, wherein the PCB is made up of different layers and wherein the striplines, including the first resonator, are located inside the PCB so that there is no direct contact between the conductors from which the striplines are built up and the fluid to be examined. 8. Sensor volgens een van de voorgaande conclusies 1 t/m 7 waarbij niet alleen tenminste een gat in de PCB tenminste gedeeltelijk is gevuld met het te onderzoeken fluïdum maar ook de PCB zelf tenminste deels in het fluïdum is 35 geplaatst.8. Sensor as claimed in any of the foregoing claims 1-7, wherein not only at least one hole in the PCB is at least partially filled with the fluid to be examined, but also the PCB itself is placed at least partially in the fluid. 9. Sensor volgens een van de voorgaande conclusies 1 t/m 8 waarbij het te onderzoeken fluïdum drinkwater is.Sensor according to one of the preceding claims 1 to 8, wherein the fluid to be examined is drinking water. 10. Sensor volgens een van de voorgaande concusies 1 t/m 8 waarbij het te onderzoeken fluidum afvalwater is.Sensor according to one of the preceding claims 1 to 8, wherein the fluid to be examined is waste water. 11. Sensor volgens een van de voorgaande conclusies 1 t/m 8 waarbij het te onderzoeken fluidum een voedingsmiddel is.Sensor according to one of the preceding claims 1 to 8, wherein the fluid to be examined is a food product. 12. Werkwijze om de dielektrische eigenschappen van een fluidum te meten dat voor meer dan 10 volumeprocenten uit vloeistof bestaat, gekenmerkt door een inrichting volgens een van de voorgaande conclusies 1 t/m 11. 10 15 20 25 30 35 103973212. Method for measuring the dielectric properties of a fluid consisting of liquid for more than 10 volume percent, characterized by a device according to one of the preceding claims 1 to 11. 10 15 20 25 30 35 1039732
NL1039732A 2012-07-15 2012-07-15 Method and device for measuring dielectric properties of a fluid and suppressing wave reflections. NL1039732C2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
NL1039732A NL1039732C2 (en) 2012-07-15 2012-07-15 Method and device for measuring dielectric properties of a fluid and suppressing wave reflections.
NL1040124A NL1040124C2 (en) 2012-07-15 2013-03-24 Method and device for impedance spectroscopy on an array of individual fluild samples present on an array of cavities in at least one printed circuit boards.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1039732 2012-07-15
NL1039732A NL1039732C2 (en) 2012-07-15 2012-07-15 Method and device for measuring dielectric properties of a fluid and suppressing wave reflections.

Publications (1)

Publication Number Publication Date
NL1039732C2 true NL1039732C2 (en) 2014-01-16

Family

ID=47146574

Family Applications (1)

Application Number Title Priority Date Filing Date
NL1039732A NL1039732C2 (en) 2012-07-15 2012-07-15 Method and device for measuring dielectric properties of a fluid and suppressing wave reflections.

Country Status (1)

Country Link
NL (1) NL1039732C2 (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0511651A2 (en) * 1991-04-30 1992-11-04 Ivac Corporation In-line fluid monitor system and method
WO2011005084A1 (en) * 2009-07-06 2011-01-13 Stichting Wetsus Centre Of Excellence For Sustainable Water Technology Rf antenna filter as a sensor for measuring a fluid

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0511651A2 (en) * 1991-04-30 1992-11-04 Ivac Corporation In-line fluid monitor system and method
WO2011005084A1 (en) * 2009-07-06 2011-01-13 Stichting Wetsus Centre Of Excellence For Sustainable Water Technology Rf antenna filter as a sensor for measuring a fluid

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
BART J ET AL: "Optimization of stripline-based microfluidic chips for high-resolution NMR", JOURNAL OF MAGNETIC RESONANCE, ACADEMIC PRESS, ORLANDO, FL, US, vol. 201, no. 2, 1 December 2009 (2009-12-01), pages 175 - 185, XP026789701, ISSN: 1090-7807, [retrieved on 20090909], DOI: 10.1016/J.JMR.2009.09.007 *
HOOG-ANTONYUK N A ET AL: "On-line fingerprinting of fluids using coaxial stub resonator technology", SENSORS AND ACTUATORS B: CHEMICAL: INTERNATIONAL JOURNAL DEVOTED TO RESEARCH AND DEVELOPMENT OF PHYSICAL AND CHEMICAL TRANSDUCERS, ELSEVIER S.A, SWITZERLAND, vol. 163, no. 1, 5 January 2012 (2012-01-05), pages 90 - 96, XP028461522, ISSN: 0925-4005, [retrieved on 20120114], DOI: 10.1016/J.SNB.2012.01.012 *

Similar Documents

Publication Publication Date Title
CN101501476B (en) Passive intermodulation distortion measuring method and system
US10338010B2 (en) Methods and apparatuses for analysing fluid samples
CN111426885A (en) CSRR microstrip resonance sensor for measuring complex dielectric constant and application thereof
CN108088858B (en) Double-frequency broadband microwave sensor
Cheng et al. Development of microstrip patch antenna sensing system for salinity and sugar detection in water
NL2003136C2 (en) Antenna filter, sensor system and method for measuring a fluid.
Moolat et al. Asymmetric coplanar strip based stepped monopole sensor for liquid permittivity measurements
CN108226650B (en) Broadband dielectric constant measuring device
CN2849734Y (en) Microwave chip tester
Ortoneda-Pedrola et al. Real-time sensing of NaCl solution concentration at microwave frequencies using novel Ag patterns printed on flexible substrates
NL1039732C2 (en) Method and device for measuring dielectric properties of a fluid and suppressing wave reflections.
WO2019122831A1 (en) Improvements in or relating to interface detection
Elwi On the percentage quantization of the moisture content in the Iraqi petroleum productions using microwave sensing
NL1039730C2 (en) Method and device for measuring dielectric properties of individual fluid samples present in an array of cavities in a stack of printed circuit boards.
Song et al. Impact of the ball grid array connection failures on signal integrity
CN108267642B (en) Micro-fluid electric characteristic microwave detection device
Xiao et al. A novel characterization method for water trees based on the transmission characteristics of complementary split ring resonators
CN110501355A (en) Plane microwave cavity dropping type liquid dielectric value detection sensor
RU2424508C1 (en) Method of measuring physical properties of liquid
US20210285905A1 (en) Method and Device for Measuring Dielectrics in Fluids
Alahnomi et al. Determination of solid material permittivity using T-ring resonator for food industry
NL1039729C2 (en) Method and device for measuring dielectric properties of a fluid through an array of cavities in a stack of printed circuit boards.
Roslan et al. Recent development of planar microwave sensor for material characterization of solid, liquid, and powder: a review
Khan A method for measuring dielectric properties of non-magnetic liquids and predicting their contamination level
NL1040124C2 (en) Method and device for impedance spectroscopy on an array of individual fluild samples present on an array of cavities in at least one printed circuit boards.

Legal Events

Date Code Title Description
MM Lapsed because of non-payment of the annual fee

Effective date: 20150801