Well logging detector and measuring method

Abstract

The invention provides a logging detector and a measuring method, and belongs to the technical field of logging. The logging detector comprises an antenna assembly, and the antenna assembly comprises a first antenna unit and a second antenna unit. The first antenna unit comprises a first radiation patch arranged on the first multilayer circuit board, a first feed port, and a plurality of first impedance matching circuits connected with the first radiation patch and the first feed port respectively, and the first feed port is used for sending or receiving a first polarization direction feed signal; the second antenna unit comprises a second radiation patch arranged on the second multilayer circuit board, a second feed port, and a plurality of second impedance matching circuits respectively connected with the second radiation patch and the second feed port, and the second feed port is used for sending or receiving a feed signal in a second polarization direction; the first radiation patch and the second radiation patch are mutually orthogonal and form a T shape. The broadband dual-polarization logging detector provided by the invention has the advantages of miniaturization, high polarization purity and high antenna aperture utilization rate.

Description

Technical Field

[0001] This invention belongs to the field of geophysical logging technology, specifically relating to a logging detector, a method for measuring reservoir dielectric constant, and a method for measuring reservoir resistivity. Background Technology

[0002] Dielectric logging technology utilizes the significant differences in the dielectric constants of oil, gas, and water in reservoirs to achieve fluid identification and rock physical information description, and has become one of the effective logging techniques for evaluating complex reservoirs. The dielectric logging detector, as a key component for transmitting and receiving electromagnetic waves, is the core of instrument development. Since the 1970s, several oilfield service companies have launched various types of dielectric logging instruments, mainly including: tens of megahertz phase dielectric logging tools using coils, gigahertz high-frequency dielectric logging tools using cavity-backed slot antennas, and tens of megahertz to gigahertz dielectric scanning logging tools using cross-electrodes and cavity-backed structures. Research has found that coil-type and cavity-backed slot antennas can only achieve single-frequency measurements, while the antenna aperture utilization and cross-polarization purity of cross-electrodes and cavity-backed structures are relatively low. Achieving high polarization purity and high space utilization for broadband dual-polarized antennas is a challenge in logging detector design. Meanwhile, well logging probes are typically placed in confined downhole spaces, such as on the eccentricity or pusher arm of downhole equipment, and perform measurements by contacting the wellbore. Due to the limited space of the pusher arm, existing well logging probes use electrically small antennas with low radiation efficiency, requiring impedance matching circuits to achieve impedance matching between the antenna and transmission line at specific frequencies. For broadband dual-polarization well logging probes, impedance matching modules for multiple frequencies are needed. Therefore, how to achieve a broadband dual-polarization well logging probe with high polarization purity and high space utilization suitable for the limited space of the eccentricity or pusher arm is a key research focus in this technical field. Summary of the Invention

[0003] The purpose of this invention is to provide a well logging detector, a method for measuring reservoir dielectric constant, and a method for measuring reservoir resistivity, in order to overcome the shortcomings of existing broadband dual-polarized dielectric well logging detectors composed of antenna units such as cross-arrays and cavity-type structures, which have low antenna aperture utilization and low cross-polarization purity.

[0004] To achieve the above objectives, a first aspect of the present invention provides a well logging detector, including a plurality of antenna assemblies disposed on a first base, wherein the antenna assembly includes a first antenna element and a second antenna element;

[0005] The first antenna unit includes a first radiating patch disposed on a first multilayer circuit board, a first feed port, and a plurality of first impedance matching circuits that are radio frequency connected to the first radiating patch and the first feed port respectively. The first feed port is used to transmit or receive a feed signal in a first polarization direction.

[0006] The second antenna unit includes a second radiating patch disposed on a second multilayer circuit board, a second feed port, and a plurality of second impedance matching circuits that are radio frequency connected to the second radiating patch and the second feed port respectively. The second feed port is used to transmit or receive feed signals in a second polarization direction.

[0007] The first and second radiating patches are orthogonal to each other and form a T-shape, with the first polarization direction and the second polarization direction being orthogonal to each other.

[0008] Optionally, the antenna assembly further includes a first matching circuit board, which is provided with a first radio frequency port and a third impedance matching circuit that is radio frequency connected to the first feed port and the first radio frequency port respectively. The first radio frequency port is used to transmit or receive a feed signal in a first polarization direction.

[0009] Optionally, the antenna assembly further includes a second matching circuit board, which is provided with a second radio frequency port and a fourth impedance matching circuit that is radio frequency connected to the second feed port and the second radio frequency port respectively. The second radio frequency port is used to transmit or receive feed signals in the second polarization direction.

[0010] Optionally, the antenna assembly is integrally mounted on the first base.

[0011] Optionally, the feed signal in the first polarization direction is a horizontal polarization direction feed signal, and the feed signal in the second polarization direction is a vertical polarization direction feed signal.

[0012] Optionally, the well logging detector further includes an antenna shield, which has multiple metal cavities with an open end. Each antenna component is correspondingly disposed in each metal cavity. Each metal cavity has a first slit on its bottom wall that is directly opposite to the first radiating patch in the corresponding antenna component and penetrates through the thickness direction of the bottom wall of the metal cavity. Each metal cavity also has a second slit on its bottom wall that is directly opposite to the second radiating patch in the corresponding antenna component and penetrates through the thickness direction of the bottom wall of the metal cavity.

[0013] Optionally, the first multilayer circuit board includes a first circuit carrier board and a second circuit carrier board stacked together. The first radiating patch is disposed on the surface of the first circuit carrier board away from the second circuit carrier board. The first impedance matching circuit and the first power supply port are disposed on the second circuit carrier board. The first radiating patch is connected to the first end of the first impedance matching circuit via a first stripline. The second end of the first impedance matching circuit is connected to the first power supply port via a first radio frequency interconnect.

[0014] Optionally, the second multilayer circuit board includes a third circuit carrier and a fourth circuit carrier stacked together. The second radiating patch is disposed on the surface of the third circuit carrier away from the fourth circuit carrier. The second impedance matching circuit and the second power supply port are disposed on the fourth circuit carrier. The second radiating patch is connected to the first end of the second impedance matching circuit via a second stripline. The second end of the second impedance matching circuit is connected to the second power supply port via a second radio frequency interconnect.

[0015] A second aspect of the present invention provides a method for measuring the dielectric constant of a reservoir, comprising:

[0016] Push the logging probe against the wellbore wall of the target section of the wellbore;

[0017] Send a first control signal to the well logging detector so that each subarray in the well logging detector emits electromagnetic waves of its own corresponding frequency and polarization direction to the formation in a time-division manner according to the measurement time sequence, and receives electromagnetic waves of its own corresponding frequency and polarization direction after propagation through the formation.

[0018] The dielectric constant data of the target layer are obtained by inverting the electromagnetic waves after they propagate through the strata.

[0019] A third aspect of the present invention provides a method for measuring reservoir resistivity, comprising:

[0020] Push the logging probe against the wellbore wall of the target section of the wellbore;

[0021] Send a first control signal to the well logging detector so that each subarray in the well logging detector emits electromagnetic waves of its own corresponding frequency and polarization direction to the formation in a time-division manner according to the measurement time sequence, and receives electromagnetic waves of its own corresponding frequency and polarization direction after propagation through the formation.

[0022] The resistivity data of the target layer is obtained by inverting the electromagnetic waves after they propagate through the strata.

[0023] In the above technical solution, the first polarization direction and the second polarization direction are orthogonal to each other. The first radiating patch used for transmitting or receiving electromagnetic waves in the first polarization direction and the second radiating patch used for transmitting or receiving electromagnetic waves in the second polarization direction are orthogonally arranged and form a T-shape. This improves the cross-polarization isolation of each antenna component within the logging detector and reduces mutual interference between electromagnetic waves in different polarization directions, thereby improving the measurement accuracy of the logging detector. Secondly, the T-shaped structure formed by the first and second radiating patches also improves the utilization rate of the antenna aperture. Furthermore, by implementing the first impedance matching circuits, the first radiating patch, and the first feed port for impedance matching at different frequencies on a multilayer circuit board using a process such as multilayer circuit board fabrication, and by implementing the second impedance matching circuits, the second radiating patch, and the second feed port for impedance matching at different frequencies on a multilayer circuit board using a process such as multilayer circuit board fabrication, the logging detector achieves broadband functionality within a limited space.

[0024] In summary, the broadband dual-polarization logging detector achieved by the above technical solution combines miniaturization, high cross-polarization isolation, and high antenna aperture utilization, resulting in high accuracy of reservoir parameters measured using this broadband dual-polarization logging detector.

[0025] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0026] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0027] Figure 1 The schematic diagram illustrates the structure of a well logging detector according to an embodiment of the present invention;

[0028] Figure 2 This schematically illustrates a first side view of the T-shaped antenna assembly;

[0029] Figure 3 A schematic diagram of the structure of the first matching circuit board is shown.

[0030] Figure 4 A schematic diagram of the structure of the second matching circuit board is shown.

[0031] Figure 5 This schematically illustrates a second side view of the T-shaped antenna assembly;

[0032] Figure 6The diagram illustrates a measurement schematic of a logging probe consisting of a central dual-transmitter and two flanking quadruple-receiver array with six antenna assemblies.

[0033] Figure 7 The diagram illustrates a measurement schematic of a well logging probe consisting of two transmitters on both sides and four receivers in the middle, comprising six antenna assemblies.

[0034] Explanation of reference numerals in the attached figures

[0035] In the figure, 1 is the antenna shield; 2 is the T-shaped antenna assembly; 201 is the first antenna unit; 202 is the second antenna unit; 203 is the first matching circuit board; 204 is the second matching circuit board; 205 is the second base; 3 is the first base; 4 is the first feed port; 5 is the third impedance matching circuit; 6 is the second feed port; 7 is the fourth impedance matching circuit; 8 is the first RF port; 9 is the second RF port; 10 is the second gap; and 11 is the first gap. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustrating and explaining the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0038] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0039] Example 1

[0040] Combination Figures 1 to 7As shown in the figure, the well logging detector provided in this embodiment of the invention is a broadband dual-polarization well logging detector, including multiple antenna components disposed on a first base 3. The antenna components include a first antenna unit 201 and a second antenna unit 202. The first antenna unit 201 includes a first radiating patch disposed on a first multilayer circuit board, a first feed port 4, and multiple first impedance matching circuits radio frequency connected to the first radiating patch and the first feed port 4, respectively. The first feed port 4 is used to transmit or receive feed signals in a first polarization direction. The second antenna unit 202 includes a second radiating patch disposed on a second multilayer circuit board, a second feed port 6, and multiple second impedance matching circuits radio frequency connected to the second radiating patch and the second feed port 6, respectively. The second feed port 6 is used to transmit or receive feed signals in a second polarization direction. The first polarization direction and the second polarization direction are orthogonal to each other. The first radiating patch and the second radiating patch are orthogonally arranged and form a T-shape.

[0041] It should be understood that in order to place the radiating patch, impedance matching circuit, etc. on the same multilayer circuit board, a multilayer circuit board manufacturing process is usually used. This embodiment does not describe the multilayer circuit board manufacturing process in the ordinary embodiment in detail.

[0042] As is known, the cross-polarization isolation between electromagnetic waves of two orthogonal polarization directions is one of the essential parameters to consider for dual-polarized antennas. In the above embodiment, by orthogonally arranging the first and second radiating patches in a T-shape, the cross-polarization isolation between the electromagnetic waves of the first polarization direction transmitted or received by the first radiating patch and the electromagnetic waves of the second polarization direction transmitted or received by the second radiating patch is improved. Furthermore, because the first and second radiating patches are orthogonally arranged in a T-shape, the antenna assembly in the following embodiments is referred to as T-shaped antenna assembly 2. Compared to the traditional dual-polarized logging detector where two radiating patches of different polarization directions are separately arranged within the antenna aperture, the T-shaped antenna assembly 2 improves the utilization rate of the antenna aperture. Furthermore, all components of the first antenna unit 201 are mounted on the same multilayer circuit board. Specifically, the first radiating patch, the first feed port 4, and multiple first impedance matching circuits that are RF connected to the first radiating patch and the first feed port 4 are all mounted on the first multilayer circuit board. Similarly, all components of the second antenna unit 202 are mounted on the same multilayer circuit board. Specifically, the second radiating patch, the second feed port 6, and multiple second impedance matching circuits that are RF connected to the second radiating patch and the second feed port 6 are all mounted on the second multilayer circuit board. Therefore, both the first antenna unit 201 and the second antenna unit 202 can be referred to as integrated antenna and feeder antennas. Through integrated antenna and feeder, wideband functionality of the logging detector is achieved within the limited space of the eccentric and pusher components. Wideband refers to a relatively wide frequency band. For example, in one specific embodiment, the logging detector supports a frequency band range of 90MHz to 1.1GHz.

[0043] For example, in a specific embodiment of the present invention, each first impedance matching circuit is used for impedance matching at different frequencies, and each second impedance matching circuit is used for impedance matching at different frequencies.

[0044] For example, in a specific embodiment of the present invention, the feed signal in the first polarization direction is a horizontal polarization direction feed signal, and the feed signal in the second polarization direction is a vertical polarization direction feed signal. For instance, when the T-type antenna assembly 2 is a transmitting antenna, after the horizontal polarization direction feed signal is fed into the first feed port 4, impedance matching between the transmission line and the radiating patch is performed by a selected first impedance matching circuit, and then the first radiating patch emits measurement electromagnetic waves in the horizontal polarization direction. After the vertical polarization direction feed signal is fed into the second feed port 6, impedance matching between the transmission line and the radiating patch is performed by a selected second impedance matching circuit, and then the second radiating patch emits measurement electromagnetic waves in the vertical polarization direction. When the T-type antenna assembly 2 is used as a receiving antenna, after the first radiating patch receives the response electromagnetic wave in the horizontal polarization direction, the transmission line and the radiating patch are impedance matched by the selected first impedance matching circuit. Then, the response electromagnetic wave in the horizontal polarization direction after impedance matching enters the back-end system through the first feed port 4. The back-end system refers to the back-end system of the antenna and is used for radio frequency signal processing. After the second radiating patch receives the response electromagnetic wave in the vertical polarization direction, the transmission line and the radiating patch are impedance matched by the selected second impedance matching circuit. Then, the response electromagnetic wave in the vertical polarization direction after impedance matching enters the back-end system through the second feed port 6.

[0045] For example, the first multilayer circuit board includes a first circuit carrier board and a second circuit carrier board stacked together. A first radiating patch is disposed on the surface of the first circuit carrier board away from the second circuit carrier board. A first impedance matching circuit and a first power supply port 4 are disposed on the second circuit carrier board. The first radiating patch is connected to a first end of the first impedance matching circuit via a first stripline. The second end of the first impedance matching circuit is connected to the first power supply port 4 via a first radio frequency interconnect.

[0046] For example, the second multilayer circuit board includes a third circuit carrier and a fourth circuit carrier. A second radiating patch is disposed on the surface of the third circuit carrier away from the fourth circuit carrier. A second impedance matching circuit and a second power supply port 6 are disposed on the fourth circuit carrier. The second radiating patch is connected to the first end of the second impedance matching circuit via a second stripline. The second end of the second impedance matching circuit is connected to the second power supply port 6 via a second radio frequency interconnect.

[0047] Example 2

[0048] Combination Figures 1 to 7As shown in Embodiment 1, the logging detector supports a wide frequency band by setting up multiple first impedance matching circuits and multiple second impedance matching circuits. For example, in a typical embodiment, the logging detector supports a frequency band of 90MHz to 1.1GHz, from low frequencies of tens of MHz to high frequencies of GHz. Experimental analysis revealed that impedance matching between the transmission line and the radiating patch is poor in the low-frequency band if only the first or second impedance matching circuits are used for impedance matching. Therefore, this embodiment introduces an impedance matching circuit located outside the integrated antenna as a supplement to the impedance matching circuit inside the integrated antenna. Accordingly, the difference between this embodiment and Embodiment 1 is that the antenna assembly also includes a first matching circuit board 203 and a second matching circuit board 204, wherein:

[0049] The first matching circuit board 203 is provided with a first radio frequency port 8 and a third impedance matching circuit 5 that is radio frequency connected to the first feed port 4 and the first radio frequency port 8 respectively. The first radio frequency port 8 is used to send or receive feed signals in the first polarization direction.

[0050] The second matching circuit board 204 is provided with a second RF port 9 and a fourth impedance matching circuit 7 that is RFly connected to the second feed port 6 and the second RF port 9 respectively. The second RF port 9 is used to send or receive feed signals in the second polarization direction.

[0051] As in the above embodiment, by introducing a third impedance matching circuit 5 as a supplement to the first impedance matching circuit inside the first antenna unit 201, and by introducing a fourth impedance matching circuit 7 as a supplement to the second impedance matching circuit inside the second antenna unit 202, the radiation efficiency of the T-type antenna assembly 2 at low frequencies is improved, thereby enhancing the accuracy of the logging detector in measuring reservoir parameters.

[0052] Example 3

[0053] Combination Figures 1 to 7 As shown, the difference between this embodiment and embodiment one is that the T-shaped antenna assembly 2 is integrally mounted on the first base 3.

[0054] As is known, an integrated setup can be achieved through processes such as all-solid-state interconnect. This embodiment does not involve any improvement to the all-solid-state interconnect process, and therefore this part will not be described in detail.

[0055] As in the above embodiment, based on the modular technical concept, the first antenna unit 201 and the second antenna unit 202 in the T-shaped antenna assembly 2 are integrated into one unit, which facilitates production and maintenance.

[0056] For example, the T-type antenna assembly 2 also includes a second base 205, on which the first antenna unit 201 and the second antenna unit 202 are disposed, and the second base 205, the first antenna unit 201 and the second antenna unit 202 are integrally disposed on the first base 3.

[0057] Example 4

[0058] Combination Figures 1 to 7 As shown, the difference between this embodiment and embodiment two is that the first antenna unit 201, the second antenna unit 202, the first matching circuit board 203 and the second matching circuit board 204 in the T-shaped antenna assembly 2 are integrated on the first base 3, that is: the T-shaped antenna assembly 2 including the first antenna unit 201, the second antenna unit 202, the first matching circuit board 203 and the second matching circuit board 204 are integrated on the first base 3.

[0059] For example, the T-type antenna assembly 2 also includes a second base 205, and the first antenna unit 201, the second antenna unit 202, the first matching circuit board 203 and the second matching circuit board 204 are all disposed on the second base 205. The second base 205, the first antenna unit 201, the second antenna unit 202, the first matching circuit board 203 and the second matching circuit board 204 are integratedly disposed on the first base 3.

[0060] Example 5

[0061] Combination Figures 1 to 7 As shown, the difference from embodiments one to four is that the well logging detector provided in this embodiment also includes an antenna shield 1. The antenna shield 1 is provided with a plurality of metal cavities with an open end. Each T-shaped antenna assembly 2 is disposed in a corresponding manner in the metal cavity. A first slit 11 is opened on the bottom wall of each metal cavity, which is directly opposite to the first radiating patch in the corresponding T-shaped antenna assembly 2 and penetrates through the thickness direction of the bottom wall of the metal cavity. A second slit 10 is opened on the bottom wall of each metal cavity, which is directly opposite to the second radiating patch in the corresponding T-shaped antenna assembly 2 and penetrates through the thickness direction of the bottom wall of the metal cavity.

[0062] As in the above embodiment, radio frequency electromagnetic isolation between each T-shaped antenna assembly 2 is achieved by using each metal cavity, thereby improving the measurement accuracy of the logging detector through physical electromagnetic isolation.

[0063] Example 6

[0064] This embodiment provides a method for measuring the dielectric constant of a reservoir using an array dielectric logging probe. The array dielectric logging probe includes the logging detector provided in any of the above embodiments. The method for measuring the dielectric constant of a reservoir includes the following steps:

[0065] Push the logging probe against the target reservoir wall in the wellbore;

[0066] Send a first control signal to the well logging detector so that each subarray in the well logging detector emits electromagnetic wave signals of its own corresponding frequency and polarization direction to the formation in a time-division manner according to the measurement time sequence, and receives electromagnetic wave signals of its own corresponding frequency and polarization direction after propagation through the formation.

[0067] The dielectric constant data of the target reservoir are obtained by inverting the electromagnetic wave signal after it propagates through the strata.

[0068] This embodiment also provides a method for measuring reservoir resistivity using an array dielectric logging probe, wherein the array dielectric logging probe includes the logging probe provided in any of the above embodiments, and the reservoir resistivity measurement method includes the following steps:

[0069] Push the logging probe against the target reservoir wall in the wellbore;

[0070] Send a first control signal to the well logging detector so that each subarray in the well logging detector emits electromagnetic wave signals of its own corresponding frequency and polarization direction to the formation in a time-division manner according to the measurement time sequence, and receives electromagnetic wave signals of its own corresponding frequency and polarization direction after propagation through the formation.

[0071] The resistivity data of the target reservoir are obtained by inverting the electromagnetic wave signal after it propagates through the strata.

[0072] In array dielectric logging probes, the logging detector typically consists of multiple subarrays, and the transmitting antenna can be shared by multiple subarrays. In a specific application, the logging detector is a dual-transmitter probe with six T-shaped antenna assemblies 2 on both sides, such as... Figure 6 As shown, it can also be a logging detector consisting of six T-shaped antenna assemblies 2, with dual transmitters on both sides and four receivers in the middle, such as... Figure 7 As shown. Figure 6 and Figure 7 In the middle, the six T-shaped antenna components 2 are: T-shaped antenna components TU and TD as transmitting antennas, and T-shaped antenna components R1U, RiU, R1D and RiD as receiving antennas. Correspondingly, the antenna shield 1 includes six metal cavities for accommodating each T-shaped antenna component 2 in a one-to-one correspondence.

[0073] For example, using by Figure 7 The process of measuring reservoir dielectric constant and resistivity using an array of logging probes shown in the diagram mainly includes:

[0074] Push the logging probe until it is flush against the wellbore wall of the target reservoir inside the wellbore;

[0075] Activate the logging probe;

[0076] When the detector is working, the T-shaped antenna components 2, which serve as transmitting antennas, alternately transmit electromagnetic wave signals with different frequencies and polarization directions in a time-division manner. The electromagnetic wave signals will experience amplitude attenuation and phase shift after passing through the stratum. Each T-shaped antenna component 2, which has the same polarization direction as the transmitting antenna and serves as the array receiving antenna, simultaneously receives the electromagnetic wave signals after propagating through the stratum. The transmit and receive spacing of each subarray is different, thereby obtaining four sets of single-transmit and single-receive path response signals.

[0077] Differential processing is performed on the response signals of the four single-transmitter and single-receiver channels to form subarray differential signals;

[0078] Using pre-constructed dielectric constant inversion charts and resistivity inversion charts, the differential signal of the subarray is inverted to obtain the dielectric constant and resistivity data of the target reservoir.

[0079] By transmitting and receiving electromagnetic wave signals of different frequencies and polarization directions through the T-type antenna assembly 2, the dielectric constant and resistivity spectrum information of multi-frequency horizontal polarization and multi-frequency vertical polarization of the reservoir can be obtained, thereby realizing the evaluation of reservoir saturation and the description of rock physical information.

[0080] In another specific application, the logging detector is a dual-transmitter in the middle and eight-receiver on both sides, comprising ten T-shaped antenna assemblies 2. Correspondingly, the antenna shield 1 is provided with ten metal cavities. Cross-polarization isolation measurements were performed on this logging detector at five discrete frequency points within the 90MHz–1.1GHz frequency band. The measurement results show that the cross-polarization isolation is greater than 40dB at each discrete frequency point. This indicates that efficient isolation is achieved between different polarization signals, thereby improving the measurement accuracy of reservoir measurements using the logging detectors provided in the above embodiments.

[0081] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0082] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A well logging detector, characterized in that, It includes multiple antenna assemblies disposed on a first base, wherein the antenna assemblies include a first antenna element and a second antenna element; The first antenna unit includes a first radiating patch disposed on a first multilayer circuit board, a first feed port, and a plurality of first impedance matching circuits that are radio frequency connected to the first radiating patch and the first feed port respectively. The first feed port is used to transmit or receive a feed signal in a first polarization direction. The second antenna unit includes a second radiating patch disposed on a second multilayer circuit board, a second feed port, and a plurality of second impedance matching circuits that are radio frequency connected to the second radiating patch and the second feed port respectively. The second feed port is used to transmit or receive feed signals in a second polarization direction. The first and second radiating patches are orthogonal to each other and form a T-shape, with the first polarization direction and the second polarization direction being orthogonal to each other.

2. The well logging detector according to claim 1, characterized in that, The antenna assembly further includes a first matching circuit board, on which a first radio frequency port and a third impedance matching circuit are provided, which are respectively radio frequency connected to the first feed port and the first radio frequency port. The first radio frequency port is used to transmit or receive feed signals in a first polarization direction.

3. The well logging detector according to claim 2, characterized in that, The antenna assembly further includes a second matching circuit board, which is provided with a second radio frequency port and a fourth impedance matching circuit that is radio frequency connected to the second feed port and the second radio frequency port respectively. The second radio frequency port is used to transmit or receive feed signals in the second polarization direction.

4. The logging detector according to any one of claims 1-3, characterized in that, The antenna assembly is integrally mounted on the first base.

5. The well logging detector according to claim 1, characterized in that, The feed signal in the first polarization direction is a horizontal polarization direction feed signal, and the feed signal in the second polarization direction is a vertical polarization direction feed signal.

6. The well logging detector according to claim 1, characterized in that, It also includes an antenna shield, on which a plurality of metal cavities with an open end are formed. Each antenna component is disposed in a corresponding metal cavity. A first slit is formed on the bottom wall of each metal cavity, which is directly opposite to the first radiating patch in the corresponding antenna component and extends through the thickness direction of the bottom wall of the metal cavity. A second slit is formed on the bottom wall of each metal cavity, which is directly opposite to the second radiating patch in the corresponding antenna component and extends through the thickness direction of the bottom wall of the metal cavity.

7. The well logging detector according to claim 1, characterized in that, The first multilayer circuit board includes a first circuit carrier board and a second circuit carrier board stacked together. The first radiating patch is disposed on the surface of the first circuit carrier board away from the second circuit carrier board. The first impedance matching circuit and the first power supply port are disposed on the second circuit carrier board. The first radiating patch is connected to the first end of the first impedance matching circuit via a first stripline. The second end of the first impedance matching circuit is connected to the first power supply port via a first radio frequency interconnect.

8. The well logging detector according to claim 1, characterized in that, The second multilayer circuit board includes a third circuit carrier board and a fourth circuit carrier board stacked together. The second radiating patch is disposed on the surface of the third circuit carrier board away from the fourth circuit carrier board. The second impedance matching circuit and the second power supply port are disposed on the fourth circuit carrier board. The second radiating patch is connected to the first end of the second impedance matching circuit via a second stripline. The second end of the second impedance matching circuit is connected to the second power supply port via a second radio frequency interconnect.

9. A method for measuring the dielectric constant of a reservoir, characterized in that, include: Push the logging probe against the wellbore wall of the target section of the wellbore; Send a first control signal to the well logging detector so that each subarray in the well logging detector emits electromagnetic waves of its own corresponding frequency and polarization direction to the formation in a time-division manner according to the measurement time sequence, and receives electromagnetic waves of its own corresponding frequency and polarization direction after propagation through the formation. The dielectric constant data of the target layer are obtained by inverting the electromagnetic waves after they propagate through the strata.

10. A method for measuring reservoir resistivity, characterized in that, include: Push the logging probe against the wellbore wall of the target section of the wellbore; Send a first control signal to the well logging detector so that each subarray in the well logging detector emits electromagnetic waves of its own corresponding frequency and polarization direction to the formation in a time-division manner according to the measurement time sequence, and receives electromagnetic waves of its own corresponding frequency and polarization direction after propagation through the formation. The resistivity data of the target layer is obtained by inverting the electromagnetic waves after they propagate through the strata.

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