Building structure multidirectional inclination sensor and monitoring system based on double patch antennas

Abstract

The invention belongs to the field of building structure health monitoring, and relates to a building structure multidirectional inclination sensor based on double patch antennas and a monitoring system. The sensor provided by the invention can be installed on a building structure to realize sensing of multidirectional inclination of the building structure; inclination of the building structure in different directions causes change of the height of liquid in a covering container of the X-direction patch antenna and the Y-direction patch antenna, and further causes change of electromagnetic parameters such as resonant frequencies of the X-direction patch antenna and the Y-direction patch antenna. By decoupling the resonant frequency change of the two patch antennas, the inclination direction and degree of the building structure can be determined; the reading device of the monitoring system can wirelessly read the resonant frequency change of the patch antennas of the sensor in two different directions, thereby realizing the wireless monitoring of the multidirectional inclination of the building structure.

Description

Technical Field

[0001] The invention belongs to the field of building structure health monitoring, and relates to a building structure multi-directional tilt sensor and a monitoring system based on double patch antennas. Background Art

[0002] During long-term use, buildings are prone to tilt due to factors such as uneven settlement. The tilt of a building will lead to uneven stress on the structure, and excessive tilt can easily cause the entire building to overturn or be damaged. Therefore, during the entire service process of the building structure, it is necessary to monitor the tilt of the building structure in real time in order to understand the service status of the building structure in a timely manner and ensure the safe use of the building structure.

[0003] At present, there are many types of sensor devices for monitoring building tilt in engineering projects, such as building structure tilt sensors based on liquid plane level monitoring, optical fiber tilt sensors, gyroscopes and other sensing technologies. These sensors can effectively monitor the tilt of building structures, but the current sensors used for monitoring building structure tilt can usually only monitor the tilt of a certain direction of the building structure. It is still difficult to use a single tilt sensor to monitor the multi-directional tilt of the building structure. In addition, since most of the current tilt sensors require a continuous power supply and use wired methods for signal transmission, this will lead to complex wiring of the monitoring system, time-consuming and labor-intensive installation, and high cost, which limits its application in actual engineering structures. Summary of the invention

[0004] In order to solve the problem that the tilt sensor requires wired signal transmission and power supply, and to solve the shortcoming that traditional tilt sensors usually only perform sensing and monitoring on the building tilt in a single direction, the present invention provides a building structure multi-directional tilt sensor and monitoring system based on dual patch antennas, which can be installed in a building structure to realize the monitoring of the building structure's multi-directional tilt.

[0005] The present invention is achieved through the following technical solutions: A building structure multi-directional tilt sensor based on a dual-patch antenna, the building structure multi-directional tilt sensor comprising component one and component two; The component 1 comprises a high-frequency dielectric plate (1), a ground plane (2) located on the lower surface of the high-frequency dielectric plate (1), an X-direction patch antenna (3), a Y-direction patch antenna (4), a microstrip feed line (5), and a radio frequency chip (6); The X-direction patch antenna (3), the Y-direction patch antenna (4), the microstrip feed line (5) and the radio frequency chip (6) are all arranged on the upper surface of the high-frequency dielectric plate (1); the X-direction patch antenna (3) and the Y-direction patch antenna (4) are connected to the radio frequency chip (6) via a bifurcated Y-shaped microstrip feed line (5); The second component comprises an overlying liquid container (7) and a high dielectric constant liquid (8) contained in the overlying liquid container (2); The overlying liquid container (7) is a cube or a rectangular parallelepiped; the overlying liquid container (7) is arranged above the X-direction patch antenna (3) and the Y-direction patch antenna (4), and two sides of the overlying liquid container are respectively aligned with the edges of the X-direction patch antenna (3) and the Y-direction patch antenna (4).

[0006] Furthermore, the material of the ground plane (2) is copper; The X-direction patch antenna (3) and the Y-direction patch antenna (4) have the same structure, comprising two layers of metal sheets, an upper layer and a lower layer, and an intermediate dielectric layer located between the two layers of metal sheets; The X-direction patch antenna (3) and the Y-direction patch antenna (4) are both rectangular; The radio frequency chip (6) is welded on the high-frequency dielectric plate (1).

[0007] Furthermore, the length of the X-direction patch antenna (3) in the X-axis direction is L x , the length of the Y-direction patch antenna (4) in the Y-axis direction is L y , and L x ≠L y .

[0008] Furthermore, the material of the overlying liquid container (7) is acrylic, and the overlying liquid container (7) is sealed as a whole, and the overlying liquid container (7) contains high dielectric constant liquid and air inside.

[0009] Furthermore, when the overlying liquid container (7) is placed horizontally, the average height of the high dielectric constant liquid (8) inside the overlying liquid container (7) is h0; The length L of the side of the upper liquid container (7) in the X-axis direction ab Greater than the length L of the X-direction patch antenna (3) x ; and the length L of the side of the upper liquid container (7) in the Y-axis direction ad Greater than the length L of the Y-direction patch antenna (4) y .

[0010] Furthermore, the components 1 and 2 of the building structure multi-directional tilt sensor are installed horizontally on the building structure as a whole. When the building structure tilts, the building structure multi-directional tilt sensor tilts the same as the building structure, thereby changing the liquid level of the high dielectric constant liquid (8) in the overlying liquid container (7). The degree of inclination of the building structure in the X and Y directions is determined by determining the height of the liquid level of the high dielectric constant liquid (8) inside the overlying liquid container (7).

[0011] Furthermore, the calculation method of the inclination degree of the building structure in the X and Y directions includes: S1: Assume that point a, point b, point c and point d are the contact points between the four corners of the overlying liquid container and the high-frequency dielectric plate, and point a is the intersection of the extension line of the outer edge of the patch antenna in the X direction and the extension line of the outer edge of the patch antenna in the Y direction, point b is on the extension line of the outer edge of the patch antenna in the X direction, and point d is on the extension line of the outer edge of the patch antenna in the Y direction; S2: The liquid level h after the building structure is tilted is inferred by the change of the resonant frequency of the patch antenna in the X direction and the patch antenna in the Y direction a ,h b and h d ; h a represents the height of the liquid level above point a, h b represents the height of the liquid level above point b, h d Indicates the liquid level height above point d; S3: The inclination of the building structure in the X-axis and Y-axis directions meets the following requirements: (1) (2) in, Indicates the inclination of the building structure in the X-axis direction; Indicates the inclination of the building structure in the Y-axis direction; L ab is the length of the side of the overlying liquid container in the X-axis direction, L ad is the length of the side of the overlying liquid container in the Y-axis direction; S4: After synthesizing the inclination vectors of the building structure in the X-axis and Y-axis directions, 360° inclination direction and inclination degree sensing in the plane is achieved.

[0012] Further, in step S2, the liquid level h after the building structure is tilted is inferred by the change of the resonant frequency of the patch antenna in the X direction and the patch antenna in the Y direction. a ,h b and h d , including: S21: According to the relevant electromagnetic theory, the calculation formula of the resonant frequency of the X-direction patch antenna and the Y-direction patch antenna is expressed as: (3) (4) in, is the resonant frequency of the patch antenna in the X direction, is the resonant frequency of the patch antenna in the Y direction; c is the propagation speed of electromagnetic waves in vacuum, is the effective dielectric constant of the high-frequency dielectric plate within the range of the patch antenna in the X direction; is the effective dielectric constant of the high-frequency dielectric plate within the Y-direction patch antenna range, and They are all affected by the height of the high dielectric constant liquid in the liquid container covering the patch antenna; in, and It is expressed as: (5) (6) in, is the initial dielectric constant of the high-frequency dielectric plate; k is the correlation coefficient between the effective dielectric constant and the height of the high dielectric constant liquid in the liquid container above the patch antenna; in, (7) Then formula (6) can be rewritten as: (8) Combining equations (3), (4), (5), and (8), we can calculate h a and h b ; Then, h is calculated by formula (7): d .

[0013] A building structure multi-directional tilt monitoring system based on dual patch antennas, comprising the building structure multi-directional tilt sensor and a reader (9); The building structure multi-directional tilt sensor is installed on the top of the building structure, and the reader (9) is placed in the vicinity of the building to be tested; The reader (9) transmits a frequency sweeping electromagnetic wave to the radio frequency chip (6) in the building structure multi-directional tilt sensor to activate the radio frequency chip (6); After the radio frequency chip (6) is activated, it generates current and transmits an electromagnetic wave signal through the patch antenna. After the electromagnetic wave signal is received by the reader (9), data processing is performed to obtain the tilt direction and tilt degree of the building structure.

[0014] Furthermore, the reader (9) comprises a wireless transceiver module, a control module, a modulation and demodulation module, and a digital processing module; The wireless transceiver module includes a transmitting and receiving antenna, which is used to transmit and receive modulated electromagnetic wave signals of different frequencies to the radio frequency chip in the building structure multi-directional tilt sensor; The modulation and demodulation module is used to modulate and demodulate the electromagnetic wave signals transmitted and received by the wireless transceiver module, and transmit the data information contained in the electromagnetic wave signals to the control module and the digital processing module; the data information includes the tilt sensor number and the measuring point position; The control module is used to control the reader to transmit modulated electromagnetic wave signals of different frequencies to the tilt sensor, and detect the threshold activation power of the radio frequency chip in the building structure multi-directional tilt sensor under the action of electromagnetic waves of different frequencies, thereby obtaining the resonant frequency information of the patch antennas in different directions in the sensor; The digital processing module calculates the inclination of the building structure in the X and Y directions according to the change in the resonant frequency of the patch antennas in two different directions of the sensor, and realizes the inclination monitoring of the building structure where the sensor is installed after vector synthesis.

[0015] Beneficial technical effects of the present invention: (1) The sensor provided by the present invention is provided with a covering liquid container and a high dielectric constant liquid on a double-patch antenna. The liquid level of the high dielectric constant liquid in the container changes due to the tilt of the building structure, thereby causing the resonant frequency of the double-patch antenna to change, thereby realizing monitoring and sensing of the tilt of the building structure.

[0016] (2) The present invention establishes a corresponding relationship between the resonant frequency of the dual-patch antenna and the inclination of the building structure in different directions. According to the change and decoupling of the resonant frequency of the dual-patch antenna, the quantitative characterization of the multi-directional inclination of the building structure can be achieved.

[0017] (3) In the present invention, the sizes of the two patch antennas are designed differently so that their initial resonant frequencies are different, thereby avoiding frequency band interference in actual use and ensuring the accuracy of monitoring and sensing of multi-directional tilt.

[0018] (4) The present invention can realize passive wireless monitoring of the tilt of building structures. Passive means that the sensor end based on the dual patch antenna does not need energy input through a power source such as a battery, and wireless means that no cables are required for signal transmission. The present invention realizes passive wireless tilt monitoring of building structures by transmitting and receiving electromagnetic waves for energy input and wireless inquiry, avoiding the dependence of traditional tilt sensors on power and cables, and reducing the traditional installation and wiring costs of monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of a component 1 in an embodiment of the present invention; Figure 2 This is a schematic diagram of component 2 in an embodiment of the present invention; Figure 3 A top view of a building structure multi-directional tilt sensor based on dual patch antennas in an embodiment of the present invention; Figure 4 Schematic diagram of the height of the liquid plane in the X direction when the X axis is tilted in the positive direction in an embodiment of the present invention; Figure 5 Schematic diagram of the height of the liquid plane in the Y direction when the X axis is tilted in the positive direction in an embodiment of the present invention; Figure 6 Schematic diagram of a building structure multi-directional tilt monitoring system based on dual patch antennas in an embodiment of the present invention; Figure numerals: 1. high frequency dielectric board; 2. ground plane; 3. patch antenna in X direction; 4. patch antenna in Y direction; 5. microstrip feed line; 6. radio frequency chip; 7. overlying liquid container; 8. high dielectric constant liquid; 9. reader. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0021] On the contrary, the present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention as defined by the claims. Further, in order to make the public have a better understanding of the present invention, some specific details are described in detail in the detailed description of the present invention below. Those skilled in the art can fully understand the present invention without the description of these details.

[0022] Embodiment 1: A building structure multi-directional tilt sensor based on dual patch antennas, the building structure multi-directional tilt sensor comprising component one and component two; like Figure 1 As shown, the component 1 includes a high-frequency dielectric plate 1, a ground plane 2 located on the lower surface of the high-frequency dielectric plate 1, an X-direction patch antenna 3, a Y-direction patch antenna 4, a microstrip feed line 5, and a radio frequency chip 6; wherein the radio frequency chip is an RFID radio frequency chip; The X-direction patch antenna 3, the Y-direction patch antenna 4, the microstrip feed line 5 and the radio frequency chip 6 are all arranged on the upper surface of the high-frequency dielectric board 1; the X-direction patch antenna 3 and the Y-direction patch antenna 4 are connected to the radio frequency chip 6 through a forked Y-shaped microstrip feed line 5; specifically, the X-direction patch antenna 3 is arranged along the X-axis direction, and the Y-direction patch antenna 4 is arranged along the Y-axis direction, and the two patch antennas do not touch each other; like Figure 2 As shown, the component 2 includes an overlying liquid container 7 and a high dielectric constant liquid 8 contained in the overlying liquid container 2; The overlying liquid container 7 is a cube or a cuboid; the overlying liquid container 7 is arranged above the X-direction patch antenna 3 and the Y-direction patch antenna 4, and the two sides of the overlying liquid container are respectively aligned with the edges of the X-direction patch antenna 3 and the Y-direction patch antenna 4, such as Figure 3 Specifically, the overlying liquid container 7 is glued on the top of the X-direction patch antenna 3 and the Y-direction patch antenna 4 to prevent the position of the overlying liquid container 7 from changing.

[0023] In this embodiment, the material of the high-frequency dielectric board 1 is RT5880 high-frequency dielectric board, or RO3010 and FR4 high-frequency dielectric board.

[0024] The material of the ground plane 2 is copper; The X-direction patch antenna 3 and the Y-direction patch antenna 4 have the same structure, including two layers of metal sheets, an upper layer and a lower layer, and an intermediate dielectric layer located between the two layers of metal sheets; The X-direction patch antenna 3 and the Y-direction patch antenna 4 are both rectangular; The radio frequency chip 6 is welded on the high frequency dielectric board 1 .

[0025] Specifically, the material of the metal sheets in the X-direction patch antenna 3 and the Y-direction patch antenna 4 are both copper; and the material of the intermediate dielectric layer is the same as that of the high-frequency dielectric plate 1 .

[0026] Specifically, the radio frequency chip 6 is welded to a corner point or an end of the high frequency dielectric board close to the patch antenna, and is connected to the two patch antennas through a bifurcated microstrip transmission line.

[0027] In this embodiment, the length of the X-direction patch antenna 3 in the X-axis direction is L x The length of the Y-direction patch antenna 4 in the Y-axis direction is L y , and L x ≠L y .

[0028] L x and L y The preferred length can be set to ly = (0.6-0.9) L x , preferably ly=0.8L x For example, the length of the patch antenna in the X direction is set to 10 cm, and the length of the patch antenna in the Y direction is set to about 6-9 cm, preferably 8 cm. The patch width generally does not exceed 50% of the patch length.

[0029] In this embodiment, the material of the overlying liquid container 7 is acrylic, and the overlying liquid container 7 is sealed as a whole, and there is a high dielectric constant liquid and air inside the overlying liquid container 7. The acrylic material selected for the overlying liquid container 7 is non-conductive and has a stable dielectric constant.

[0030] In this embodiment, when the overlying liquid container 7 is placed horizontally, the average height of the high dielectric constant liquid 8 inside the overlying liquid container 7 is h0; Preferably, the average height h0 is set to 40-60% of the height of the overlying liquid container 7, preferably 50%; at this time, when the average height h0 is set to 50% of the height of the overlying liquid container 7, the inclination angle range that the sensor can measure is ±2*h0 / L ab (The range of inclination angles that can be measured in the X direction) or ±2*h0 / L ad (The range of tilt angles that can be measured in the Y direction); like Figure 3 As shown, the length L of the side of the upper liquid container 7 in the X-axis direction is ab Greater than the length L of the X-direction patch antenna 3 x ; and the length L of the side of the overlying liquid container 7 in the Y-axis direction ad Greater than the length L of the Y-direction patch antenna 4 y .

[0031] In this embodiment, the components 1 and 2 of the building structure multi-directional tilt sensor are installed horizontally on the building structure as a whole. When the building structure tilts, the building structure multi-directional tilt sensor tilts the same as the building structure, and then the liquid level of the high dielectric constant liquid 8 in the overlying liquid container 7 changes. The degree of inclination of the building structure in the X and Y directions is determined by determining the height of the liquid level of the high dielectric constant liquid 8 in the overlying liquid container 7 .

[0032] In this embodiment, the method for calculating the inclination of the building structure in the X and Y directions includes: S1: Figure 3 As shown, let point a, point b, point c and point d be the contact points between the four corners of the overlying liquid container and the high-frequency dielectric plate, and point a be the intersection of the extension line of the outer side of the patch antenna in the X direction and the extension line of the outer side of the patch antenna in the Y direction, point b be on the extension line of the outer side of the patch antenna in the X direction, and point d be on the extension line of the outer side of the patch antenna in the Y direction; S2: The liquid level h after the building structure is tilted is inferred by the change of the resonant frequency of the patch antenna in the X direction and the patch antenna in the Y direction a ,h b and hd ; h a represents the height of the liquid level above point a, h b represents the height of the liquid level above point b, h d Indicates the liquid level height above point d; S3: The inclination of the building structure in the X-axis and Y-axis directions meets the following requirements: (1) (2) in, Indicates the inclination of the building structure in the X-axis direction; Indicates the inclination of the building structure in the Y-axis direction; L ab is the length of the side of the overlying liquid container in the X-axis direction, L ad is the length of the side of the overlying liquid container in the Y-axis direction; S4: After synthesizing the inclination vectors of the building structure in the X-axis and Y-axis directions, the inclination direction and degree of inclination of 360° in the plane are realized. In this step, after synthesizing the inclination vectors of the building structure in the X-axis and Y-axis directions, the inclination direction and degree of the building structure can be determined. The inclination direction can be any direction within the 360° range in the plane, thus avoiding the disadvantage that the traditional sensor can only sense the inclination in a single direction.

[0033] In this embodiment, step S2 is to inversely calculate the liquid level h after the building structure is tilted by the change of the resonant frequency of the patch antenna in the X direction and the patch antenna in the Y direction. a ,h b and h d , including: S21: According to the relevant electromagnetic theory, the calculation formula of the resonant frequency of the X-direction patch antenna and the Y-direction patch antenna is expressed as: (3) (4) in, is the resonant frequency of the patch antenna in the X direction, is the resonant frequency of the patch antenna in the Y direction; c is the propagation speed of electromagnetic waves in vacuum, is the effective dielectric constant of the high-frequency dielectric plate within the range of the patch antenna in the X direction; is the effective dielectric constant of the high-frequency dielectric plate within the Y-direction patch antenna range, and They are all affected by the height of the high dielectric constant liquid in the liquid container covering the patch antenna; Since the container above the patch antenna contains a liquid with a dielectric constant much higher than that of air, it will have a certain impact on the effective dielectric constant. According to the relevant electromagnetic theory, the effective dielectric constant is and It is correlated with the initial dielectric constant and the height of the liquid overlying the patch antenna. Let the correlation be k； in, and It is expressed as:

[0034] (5) (6) in, is the initial dielectric constant of the high-frequency dielectric plate; k is the correlation coefficient between the effective dielectric constant and the height of the high dielectric constant liquid in the liquid container above the patch antenna; the value of the correlation coefficient k needs to be determined according to the type of high dielectric constant liquid through simulation and experiments.

[0035] Since the liquid in the container is completely sealed, point a and point d are points on the diagonal of the container (such as Figure 3 ), so there is always: (7) Then formula (6) can be rewritten as: (8) By combining equations (3), (4), (5), and (8), the two variables, the resonant frequency change of the patch antenna in the X direction and the resonant frequency change of the patch antenna in the Y direction, are decoupled and calculated to obtain h a and h b ; Then, h is calculated by formula (7): d .

[0036] Embodiment 2: A building structure multi-directional tilt monitoring system based on dual patch antennas, characterized by comprising the building structure multi-directional tilt sensor and reader 9 described in Embodiment 1; The building structure multi-directional tilt sensor is installed on the top of the building structure, and the reader 9 is placed in the vicinity of the building to be tested; specifically, the reader 9 is placed at any position in the vicinity of the building to be tested, but care should be taken to avoid large-area metal shielding that affects the transmission of electromagnetic wave signals.

[0037] The reader 9 transmits a frequency sweeping electromagnetic wave to the radio frequency chip 6 in the multi-directional tilt sensor of the building structure to activate the radio frequency chip 6; After the radio frequency chip 6 is activated, it generates current and transmits electromagnetic wave signals through the patch antenna. After the electromagnetic wave signals are received and processed by the reader 9, data processing is performed to obtain the tilt direction and tilt degree of the building structure.

[0038] In this embodiment, the reader 9 includes a wireless transceiver module, a control module, a modulation and demodulation module, and a digital processing module; The wireless transceiver module includes a transmitting and receiving antenna, which is used to transmit and receive modulated electromagnetic wave signals of different frequencies to the radio frequency chip in the building structure multi-directional tilt sensor; Specifically, the wireless transceiver module transmits modulated electromagnetic wave signals of different frequencies to the multi-directional tilt sensor of the building structure based on dual patch antennas installed on the building structure; the patch antenna in the X direction and the patch antenna in the Y direction of the sensor are designed with different sizes and have different initial resonant frequencies, so the signals of the two patch antennas can be better distinguished; when the sensor RF chip 6 receives an electromagnetic wave signal corresponding to the resonant frequency of the patch antenna in any direction, the threshold activation power of the RF chip 6 will be significantly reduced, and the RF chip 6 will be activated to work. After the RF chip 6 is activated, it generates current and transmits an electromagnetic wave signal with the sensor number, measurement point location, and patch antenna resonant frequency information through the patch antenna. After the electromagnetic wave signal is received and processed by the reader 9, the sensor number, location, and resonant frequency information of the two patch antennas in different directions are obtained; The modulation and demodulation module is used to modulate and demodulate the electromagnetic wave signals transmitted and received by the wireless transceiver module, and transmit the data information contained in the electromagnetic wave signals to the control module and the digital processing module; the data information includes the tilt sensor number and the measuring point position; The control module is used to control the reader to transmit modulated electromagnetic wave signals of different frequencies to the tilt sensor, and detect the threshold activation power of the radio frequency chip in the building structure multi-directional tilt sensor under the action of electromagnetic waves of different frequencies, thereby obtaining the resonant frequency information of the patch antennas in different directions in the sensor; The digital processing module calculates the inclination of the building structure in the X and Y directions based on the resonant frequency changes of the patch antennas in two different directions of the sensor, and performs vector synthesis to monitor the inclination of the building structure where the sensor is installed. The inclination can be in any direction within the 360° range in the plane.

[0039] The building structure tilt sensor based on dual patch antennas provided by the present invention can be installed on a building structure to realize sensing of multi-directional tilt of the building structure; the tilt of the building structure in different directions will cause changes in the height of the liquid in the container covered by the X-direction patch antenna and the Y-direction patch antenna, thereby causing changes in electromagnetic parameters such as the resonant frequency of the X-direction patch antenna and the Y-direction patch antenna; by decoupling the changes in the resonant frequencies of the two patch antennas, the direction and degree of the tilt of the building structure can be determined, and the tilt direction can be any direction within a range of 360° in a plane; the reading device of the monitoring system can wirelessly read the changes in the resonant frequencies of the two patch antennas of the sensor in different directions, thereby realizing wireless monitoring of the multi-directional tilt of the building structure.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A building structure multi-directional tilt sensor based on dual patch antennas, characterized in that: The building structure multi-directional tilt sensor comprises component one and component two; The component 1 comprises a high-frequency dielectric plate (1), a ground plane (2) located on the lower surface of the high-frequency dielectric plate (1), an X-direction patch antenna (3), a Y-direction patch antenna (4), a microstrip feed line (5), and a radio frequency chip (6); The X-direction patch antenna (3), the Y-direction patch antenna (4), the microstrip feed line (5) and the radio frequency chip (6) are all arranged on the upper surface of the high-frequency dielectric plate (1); the X-direction patch antenna (3) and the Y-direction patch antenna (4) are connected to the radio frequency chip (6) via a bifurcated Y-shaped microstrip feed line (5); The second component comprises an overlying liquid container (7) and a high dielectric constant liquid (8) contained in the overlying liquid container (2); The overlying liquid container (7) is a cube or a rectangular parallelepiped; the overlying liquid container (7) is arranged above the X-direction patch antenna (3) and the Y-direction patch antenna (4), and two sides of the overlying liquid container are respectively aligned with the edges of the X-direction patch antenna (3) and the Y-direction patch antenna (4).

2. The building structure multi-directional tilt sensor based on dual patch antenna according to claim 1, characterized in that: The material of the ground plane (2) is copper; The X-direction patch antenna (3) and the Y-direction patch antenna (4) have the same structure, comprising two layers of metal sheets, an upper layer and a lower layer, and an intermediate dielectric layer located between the two layers of metal sheets; The X-direction patch antenna (3) and the Y-direction patch antenna (4) are both rectangular; The radio frequency chip (6) is welded on the high-frequency dielectric plate (1).

3. The building structure multi-directional tilt sensor based on dual patch antenna according to claim 1, characterized in that: The length of the X-direction patch antenna (3) in the X-axis direction is L x , the length of the Y-direction patch antenna (4) in the Y-axis direction is L y , and L x ≠L y .

4. The building structure multi-directional tilt sensor based on dual patch antennas according to claim 1, characterized in that: The material of the overlying liquid container (7) is acrylic, and the overlying liquid container (7) is sealed as a whole, and the overlying liquid container (7) contains high dielectric constant liquid and air.

5. The building structure multi-directional tilt sensor based on dual patch antennas according to claim 1, characterized in that: When the overlying liquid container (7) is placed horizontally, the average height of the high dielectric constant liquid (8) inside the overlying liquid container (7) is h0; The length L of the side of the upper liquid container (7) in the X-axis direction ab Greater than the length L of the X-direction patch antenna (3) x ; and the length L of the side of the upper liquid container (7) in the Y-axis direction ad Greater than the length L of the Y-direction patch antenna (4) y .

6. The building structure multi-directional tilt sensor based on dual patch antennas according to claim 1, characterized in that: Components 1 and 2 of the building structure multi-directional tilt sensor are installed horizontally on the building structure as a whole, and when the building structure tilts, the building structure multi-directional tilt sensor tilts the same as the building structure, thereby changing the liquid level of the high dielectric constant liquid (8) in the overlying liquid container (7); The degree of inclination of the building structure in the X and Y directions is determined by determining the height of the liquid level of the high dielectric constant liquid (8) inside the overlying liquid container (7).

7. The building structure multi-directional tilt sensor based on dual patch antennas according to claim 6, characterized in that: The calculation method of the inclination of the building structure in the X and Y directions includes: S1: Assume that point a, point b, point c and point d are the contact points between the four corners of the overlying liquid container and the high-frequency dielectric plate, and point a is the intersection of the extension line of the outer edge of the patch antenna in the X direction and the extension line of the outer edge of the patch antenna in the Y direction, point b is on the extension line of the outer edge of the patch antenna in the X direction, and point d is on the extension line of the outer edge of the patch antenna in the Y direction; S2: The liquid level h after the building structure is tilted is inferred by the change of the resonant frequency of the patch antenna in the X direction and the patch antenna in the Y direction a ,h b and h d ; h a represents the height of the liquid level above point a, h b represents the liquid level above point b, h d Indicates the liquid level above point d; S3: The inclination of the building structure in the X-axis and Y-axis directions meets the following requirements: （1） （2） in, Indicates the inclination of the building structure in the X-axis direction; Indicates the inclination of the building structure in the Y-axis direction; L ab is the length of the side of the overlying liquid container in the X-axis direction, L ad is the length of the side of the overlying liquid container in the Y-axis direction; S4: After synthesizing the inclination vectors of the building structure in the X-axis and Y-axis directions, 360° inclination direction and inclination degree sensing in the plane is achieved.

8. The building structure multi-directional tilt sensor based on dual patch antennas according to claim 7, characterized in that: Step S2, inversely inferring the liquid level h after the building structure is tilted by the change of the resonant frequency of the patch antenna in the X direction and the patch antenna in the Y direction a ,h b and h d , specifically including: S21: According to the relevant electromagnetic theory, the calculation formula of the resonant frequency of the X-direction patch antenna and the Y-direction patch antenna is expressed as: （3） （4） in, is the resonant frequency of the patch antenna in the X direction, is the resonant frequency of the patch antenna in the Y direction; c is the propagation speed of electromagnetic waves in vacuum, is the effective dielectric constant of the high-frequency dielectric plate within the range of the patch antenna in the X direction; is the effective dielectric constant of the high-frequency dielectric plate within the Y-direction patch antenna range, and They are all affected by the height of the high dielectric constant liquid in the liquid container covering the patch antenna; in, and It is expressed as: （5） （6） in, is the initial dielectric constant of the high-frequency dielectric plate; k is the correlation coefficient between the effective dielectric constant and the height of the high dielectric constant liquid in the liquid container above the patch antenna; in, （7） Then formula (6) can be rewritten as: （8） Combining equations (3), (4), (5), and (8), we can calculate h a and h b ; Then, h is calculated by formula (7): d .

9. A building structure multi-directional tilt monitoring system based on dual patch antennas, characterized in that: Comprising the building structure multi-directional tilt sensor and reader (9) as described in any one of claims 1 to 8; The building structure multi-directional tilt sensor is installed on the top of the building structure, and the reader (9) is placed in the vicinity of the building to be tested; The reader (9) transmits a frequency sweeping electromagnetic wave to the radio frequency chip (6) in the building structure multi-directional tilt sensor to activate the radio frequency chip (6); After the radio frequency chip (6) is activated, it generates current and transmits an electromagnetic wave signal through the patch antenna. After the electromagnetic wave signal is received by the reader (9), data processing is performed to obtain the tilt direction and tilt degree of the building structure.

10. The building structure multi-directional tilt monitoring system based on dual patch antennas according to claim 9, characterized in that: The reader (9) comprises a wireless transceiver module, a control module, a modulation and demodulation module, and a digital processing module; The wireless transceiver module includes a transmitting and receiving antenna, which is used to transmit and receive modulated electromagnetic wave signals of different frequencies to the radio frequency chip in the building structure multi-directional tilt sensor; The modulation and demodulation module is used to modulate and demodulate the electromagnetic wave signals transmitted and received by the wireless transceiver module, and transmit the data information contained in the electromagnetic wave signals to the control module and the digital processing module; the data information includes the tilt sensor number and the measuring point position; The control module is used to control the reader to transmit modulated electromagnetic wave signals of different frequencies to the tilt sensor, and detect the threshold activation power of the radio frequency chip in the building structure multi-directional tilt sensor under the action of electromagnetic waves of different frequencies, thereby obtaining the resonant frequency information of the patch antennas in different directions in the sensor; The digital processing module calculates the inclination of the building structure in the X and Y directions according to the change in the resonant frequency of the patch antennas in two different directions of the sensor, and realizes the inclination monitoring of the building structure where the sensor is installed after vector synthesis.

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