Bidirectional deformation and temperature sensor and monitoring system based on multi-frequency combined patch antenna structure

Abstract

The invention provides a bidirectional deformation and temperature sensor and monitoring system based on a multi-frequency combined patch antenna structure, and the sensor comprises a main patch antenna, a transverse deformation additional patch, a longitudinal deformation additional patch, a radio frequency chip, a heightening layer, a transverse connecting piece and a longitudinal connecting piece. One end of the transverse connecting piece is connected with the surface of the structure in an adhesive mode, the other end of the transverse connecting piece is fixedly connected with the transverse deformation additional patch, one end of the longitudinal connecting piece is connected with the surface of the structure in an adhesive mode, and the other end of the longitudinal connecting piece is fixedly connected with the longitudinal deformation additional patch. The transverse deformation additional patch and the longitudinal deformation additional patch are in close contact with the main patch antenna but not fixedly connected with the main patch antenna and can generate relative displacement, and the radio frequency chip is connected with the main patch antenna in a welded mode.

Description

Technical Field

[0001] The present invention belongs to the field of structural health monitoring, and in particular relates to a bidirectional deformation and temperature sensor and a monitoring system based on a multi-frequency combined patch antenna structure. Background Art

[0002] Civil engineering structures have the characteristics of long service life and complex service environment. More and more civil engineering structures will inevitably accumulate damage, which will further lead to deterioration of performance, reduced durability, and reduced bearing capacity, thus forming huge safety hazards. Therefore, in order to effectively monitor the health of the structure during construction and operation, the structural health monitoring system provides the necessary guarantee and support for civil engineering structures. Sensors are one of the core components of the structural health monitoring system and undertake the task of data collection and monitoring.

[0003] At present, commonly used sensors based on resistance, vibrating string, optical fiber, etc. that use electrical properties or optical principles to monitor structural performance parameters have the characteristics of high precision, real-time and long-term stability. However, most of these sensors only monitor a specific parameter, and it is difficult to achieve simultaneous monitoring of multiple parameters, which limits their application in the field of structural health monitoring. Moreover, these sensors usually require wired connections, and there are a lot of wiring problems when they are used, resulting in a lot of investment in manpower, material resources and maintenance costs. Summary of the invention

[0004] The present invention provides a bidirectional deformation and temperature sensor and monitoring system based on a multi-frequency combined patch antenna structure, which can monitor the deformation and temperature of the structure in two directions and has a simple structure and low cost. It solves the problem that traditional sensors only monitor a specific parameter and require wired connections to transmit signals and energy.

[0005] The technical solution of the patent of this invention is as follows:

[0006] The present invention relates to a bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure, comprising a main patch antenna, a transverse deformation additional patch, a longitudinal deformation additional patch, a radio frequency chip, a padding layer, a transverse connector and a longitudinal connector. The bottom of the padding layer is adhesively connected to the structure surface, and the upper part is adhesively connected to the main patch antenna. One end of the transverse connector is adhesively connected to the structure surface, and the other end is fixedly connected to the transverse deformation additional patch. One end of the longitudinal connector is adhesively connected to the structure surface, and the other end is fixedly connected to the longitudinal deformation additional patch. The transverse deformation additional patch and the longitudinal deformation additional patch are in close contact with the main patch antenna, but are not fixedly connected, and relative displacement can be generated. The radio frequency chip is welded to the main patch antenna.

[0007] The transverse connector is rigidly connected to the transverse deformation additional patch and is pasted on the structural surface near the transverse direction of the main patch antenna. The longitudinal connector is rigidly connected to the longitudinal deformation additional patch and is pasted on the structural surface near the longitudinal direction of the main patch antenna. The radiation patches of the two additional patches are in close contact with the upper radiation patch of the main patch antenna and can be shifted relative to each other. The RF chip is welded on the main patch antenna. The lower part of the padding layer is pasted on the structural surface, and the upper part is pasted and connected to the main patch antenna.

[0008] Furthermore, the main patch antenna is composed of an upper radiating patch, a dielectric substrate, a lower radiating patch and a radio frequency chip. The feed line, the temperature corresponding branches, the lateral deformation corresponding branches and the longitudinal deformation corresponding branches are the upper radiating patch of the main patch antenna. The radio frequency chip is welded on the feed line. The ground plane is the lower radiating patch of the main patch antenna. The lateral deformation corresponding branches adopt a bending design, which reduces the size of the main patch antenna 1. The ground plane does not fully cover the bottom of the dielectric substrate and does not have an anti-metal design, so a pad layer is required to increase the distance from the structural surface.

[0009] Furthermore, the lateral deformation additional patch is composed of a lateral deformation additional patch radiating patch and a lateral deformation additional patch dielectric substrate. The lateral deformation additional patch radiating patch is in close contact with the lateral deformation corresponding branch of the main patch antenna, and the lateral deformation additional patch dielectric substrate is fixedly connected to one end of the lateral connector.

[0010] Furthermore, the longitudinal deformation additional patch is composed of a longitudinal deformation additional patch radiating patch and a longitudinal deformation additional patch dielectric substrate. The longitudinal deformation additional patch radiating patch is in close contact with the longitudinal deformation corresponding branch of the main patch antenna, and the high-frequency branch additional patch dielectric substrate is fixedly connected to one end of the longitudinal connector.

[0011] Furthermore, the padding layer is located between the structure surface and the main patch antenna and is made of plastic or wood.

[0012] Furthermore, the transversely and longitudinally deformable additional patch has a radiation patch on only one side, and the width of the radiation patch is equal to the width of the corresponding branch on the main patch antenna, and the radiation patch is attached to one side of the external additional patch by electroplating.

[0013] Furthermore, the main patch antenna radiation patch, the lateral deformation additional patch radiation patch and the longitudinal deformation additional patch radiation patch are all made of copper, and the main patch antenna dielectric substrate, the lateral deformation additional patch dielectric substrate and the longitudinal deformation additional patch dielectric substrate are all made of FR4.

[0014] The present invention provides a method for monitoring using the above-mentioned bidirectional deformation and temperature sensor based on the multi-frequency combined patch antenna structure. When the surface of the structure is deformed, the transverse connector and the longitudinal connector connected to the surface of the structure will deform transversely and longitudinally:

[0015] The lateral deformation drives the lateral deformation additional patch and the main patch antenna to have a lateral relative displacement, thereby changing the equivalent length of the corresponding branch of the multi-frequency combined antenna, causing one of the resonant frequencies of the multi-frequency combined patch antenna to change;

[0016] The longitudinal deformation causes the longitudinal deformation additional patch and the main patch antenna to cause a longitudinal relative displacement, thereby changing the equivalent length of the multi-frequency combined antenna and its corresponding branch, causing another resonant frequency of the multi-frequency combined patch antenna to change. By monitoring the changes in the corresponding branch resonant frequencies, the bidirectional deformation of the structure can be monitored.

[0017] Furthermore, the sensor has three resonant frequencies, which correspond to the three branches of the antenna respectively. The movement of the additional patches for lateral and longitudinal deformation only changes the resonant frequency of the corresponding branches, but does not affect the resonant frequencies corresponding to other branches. Therefore, the two branches of the sensor affect the two resonant frequencies through the movement of the additional patches, which are used to monitor the bidirectional strain of the structure. Since the remaining branch has no external additional patch, the factor affecting the resonant frequency of the branch is temperature. By measuring the resonant frequency of the branch corresponding to the temperature, the surface temperature of the structure can be monitored.

[0018] Furthermore, when the structure undergoes bidirectional deformation and temperature changes, three resonant frequencies are used for monitoring and decoupling. The temperature is monitored through one of the resonant frequencies, and the other two resonant frequencies are corrected through temperature compensation to achieve accurate monitoring of the bidirectional deformation of the structure.

[0019] The present invention provides a bidirectional deformation and temperature monitoring system based on a multi-frequency combined patch antenna structure, comprising the bidirectional deformation and temperature sensor based on the multi-frequency combined patch antenna structure, a reader and an application software system.

[0020] Furthermore, the reader includes a radio frequency signal transceiver module, a control module and a modulation and demodulation module. The radio frequency signal transceiver module is used to transmit and receive radio frequency signals, the modulation and demodulation module is used to demodulate the received radio frequency signals, and the control module is used to modulate electromagnetic wave signals to transmit radio frequency signals of different frequencies.

[0021] Furthermore, the application software system is composed of a control module, a data processing module and a data storage module. The reader and the sensor transmit signals wirelessly through electromagnetic wave signals, and the reader is connected to the application software system for data transmission. The data processing module is used to process the radio frequency signal to obtain the offset of the resonant frequency of the combined patch antenna, the data storage module is used to store the radio frequency signal after transmission, reception and processing, and the control module is used to control the frequency range of the reader receiving and transmitting signals.

[0022] When the monitoring system is working, the reader transmits an inquiry signal to activate the radio frequency chip, and receives the radio frequency signal sent back by the chip and transmits it to the connected application software system. The application software system processes and analyzes the radio frequency signal to obtain the three resonant frequencies of the combined patch antenna sensor, thereby obtaining the temperature change and the deformation of the corresponding external additional patch, realizing the monitoring of bidirectional structural deformation and temperature.

[0023] When the RF chip receives the inquiry signal and is activated, the sensor emits an electromagnetic wave signal containing the antenna number and the antenna electrical characteristics. The corresponding reader receives the signal and transmits it to the application software system. The application software system processes the signal to obtain the sensor's position positioning and measurement parameters.

[0024] Compared with the prior art, the present invention has the following beneficial technical effects:

[0025] 1. The main patch antenna in the deformation and temperature sensor designed by the present invention adopts a branch structure, and the size and position of the branches can be flexibly adjusted as needed, so as to achieve coverage of multiple frequency bands. This design flexibility makes the sensor more advantageous in responding to diverse and complex design requirements, and the designed sensor is small in size and high in sensitivity.

[0026] 2. For the deformation and temperature sensor of the present invention, the resonant frequency of the branches without external additional patches is only affected by temperature, while the branches with external additional patches are affected by the deformation of the external additional patches in addition to the temperature, and the movement of the external additional patches only affects the change of the resonant frequency of the branches corresponding to the antenna. By monitoring the offset of the three resonant frequencies of the sensor, the synchronous monitoring of the bidirectional deformation and temperature of the structure can be achieved.

[0027] 3. The deformation and temperature sensors in the present invention have a simple structure and low cost. The reader provides energy to the radio frequency chip. At the same time, information is transmitted between monitoring systems through electromagnetic wave signals, realizing wireless passive monitoring of sensors. While eliminating the need for wiring, the flexibility of sensor node layout is improved, which greatly reduces the cost of the monitoring system and improves the applicability of the system.

[0028] 4. The sensor in the present invention adopts a combined patch antenna form, and realizes the monitoring of structural deformation by moving the additional patch. The sensor itself is not affected by stress, which can avoid the problems of deformation transmission efficiency loss and insufficient bonding strength in structural deformation monitoring, and improve the accuracy of structural deformation monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of a bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure of the present invention;

[0030] Figure 2 It is a schematic diagram of the front structure of the main patch antenna of the present invention;

[0031] Figure 3 It is a schematic diagram of the back structure of the main patch antenna of the present invention;

[0032] Figure 4 It is a schematic diagram of the structure of the lateral deformation additional patch of the present invention;

[0033] Figure 5 It is a schematic diagram of the longitudinal deformation additional patch structure of the present invention;

[0034] Figure 6 It is a structural schematic diagram of the bidirectional deformation and temperature monitoring system based on the multi-frequency combined patch antenna structure of the present invention.

[0035] Figure markings: 1-main patch antenna, 2-lateral deformation additional patch, 3-longitudinal deformation additional patch, 4-RF chip, 5-pad layer, 6-lateral connector, 7-longitudinal connector, 8-structural surface, 9-reader, 10-application software system, 101-feeder line, 102-temperature corresponding branch, 103-lateral deformation corresponding branch, 104-longitudinal deformation corresponding branch, 105-main patch antenna dielectric substrate, 106-ground plane, 201-lateral deformation additional patch radiation patch, 202-lateral deformation additional patch dielectric substrate, 301-longitudinal deformation additional patch radiation patch, 302-longitudinal deformation additional patch dielectric substrate. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of this application more clearly expressed, the following is a brief description of the present invention in conjunction with the attached Figure 1-6 Further introduction to this application.

[0037] From the attached Figure 1It can be seen that the present invention provides a bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure, which is composed of a main patch antenna 1, a lateral deformation additional patch 2, a longitudinal deformation additional patch 3, a radio frequency chip 4, a raising layer 5, a lateral connector 6 and a longitudinal connector 7. The bottom of the raising layer 5 is glued and connected to the structure surface 8, and the upper part is glued and connected to the main patch antenna 1. One end of the lateral connector 6 is glued and connected to the structure surface 8, and the other end is fixed to the lateral deformation additional patch 2. One end of the longitudinal connector 7 is glued and connected to the structure surface 8, and the other end is fixed to the longitudinal deformation additional patch 3. The lateral deformation additional patch 2 and the longitudinal deformation additional patch 3 are in close contact with the main patch antenna 1, but are not fixed, and can produce relative displacement. The radio frequency chip 4 is welded to the main patch antenna 1.

[0038] like Figure 2 and Figure 3 As shown, the main patch antenna 1 is composed of an upper radiating patch, a dielectric substrate 105, a lower radiating patch and a RF chip 4. The feed line 101, the temperature corresponding branch 102, the lateral deformation corresponding branch 103 and the longitudinal deformation corresponding branch 104 are the upper radiating patch of the main patch antenna 1, the ground plane 106 is the lower radiating patch of the main patch antenna 1, the lateral deformation corresponding branch 103 adopts a bending design, which can reduce the size of the main patch antenna 1, and the RF chip 4 is welded on the feed line 101. The ground plane 106 does not fully cover the bottom of the dielectric substrate 105 and does not have an anti-metal design, so a pad layer 5 is required to increase the distance from the structural surface 8.

[0039] like Figure 4 and Figure 5 As shown, the lateral deformation additional patch 2 is composed of a lateral deformation additional patch radiation patch 201 and a lateral deformation additional patch dielectric substrate 202. The lateral deformation additional patch radiation patch 201 is in close contact with the lateral deformation corresponding branch 103 of the main patch antenna 1, and the lateral deformation additional patch dielectric substrate 202 is fixedly connected to one end of the lateral connector 6.

[0040] The longitudinal deformation additional patch 3 is composed of a longitudinal deformation additional patch radiation patch 301 and a longitudinal deformation additional patch dielectric substrate 302. The longitudinal deformation additional patch radiation patch 301 is in close contact with the longitudinal deformation corresponding branch 104 of the main patch antenna 1, and the longitudinal deformation additional patch dielectric substrate 302 is fixedly connected to one end of the longitudinal connector 7.

[0041] The present invention provides a method for monitoring using a bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure. When the surface of the structure is deformed, the transverse connector 6 and the longitudinal connector 7 connected to the surface of the structure will deform transversely and longitudinally:

[0042] The lateral deformation drives the lateral deformation additional patch 2 and the main patch antenna 1 to have a lateral relative displacement, thereby changing the equivalent length of the corresponding branch of the multi-frequency combined antenna, causing one of the resonant frequencies of the multi-frequency combined patch antenna to change;

[0043] The longitudinal deformation drives the longitudinal deformation additional patch 3 and the main patch antenna 1 to cause longitudinal relative displacement, thereby changing the equivalent length of the multi-frequency combined antenna and the corresponding branch, causing another resonant frequency of the multi-frequency combined patch antenna to change. By monitoring the change of the corresponding branch resonant frequency, the bidirectional deformation of the structure can be monitored.

[0044] The sensor has three resonant frequencies, which correspond to the three branches of the antenna respectively. The movement of the additional patches for lateral and longitudinal deformation only changes the resonant frequency of the corresponding branches, but does not affect the resonant frequencies corresponding to other branches. Therefore, the two branches of the sensor affect the two resonant frequencies through the movement of the additional patches, which are used to monitor the bidirectional strain of the structure. Since there is no external additional patch on the remaining branch, the factor affecting the resonant frequency of the branch is temperature. By measuring the resonant frequency of the branch corresponding to the temperature, the surface temperature of the structure can be monitored.

[0045] When the structure undergoes bidirectional deformation and temperature changes, three resonant frequencies are used for monitoring and decoupling. The temperature is monitored through one of the resonant frequencies, and the other two resonant frequencies are corrected through temperature compensation to achieve accurate monitoring of the bidirectional deformation of the structure.

[0046] like Figure 6 As shown, a bidirectional deformation and temperature monitoring system based on a multi-frequency combined patch antenna structure includes the above-mentioned sensor, a reader 9 and an application software system 10. The reader 9 is composed of a radio frequency signal transceiver module, a control module and a modulation and demodulation module, and the application software 10 is composed of a control module, a data processing module and a data storage module. The reader 9 and the sensor are wirelessly transmitted through electromagnetic wave signals, and the reader 9 and the application software system 10 are wired for wired data transmission.

[0047] In the present invention, the main patch antenna 1 adopts a branch structure, adjusts the size and position of the branches to achieve dual-band characteristics, and together with the lateral deformation additional patch 2 and the longitudinal deformation additional patch 3, forms a combined patch antenna, wherein the lateral deformation corresponding branch 103 and the lateral deformation additional patch radiation patch 201 form equivalent lateral deformation branches, and the longitudinal deformation corresponding branch 104 and the longitudinal deformation additional patch radiation patch 301 form equivalent longitudinal deformation branches.

[0048] The resonant frequency band of the combined patch antenna sensor is related to the corresponding branch length. The longer the branch length, the lower the resonant frequency. In this example, the equivalent lateral deformation branch, the equivalent longitudinal deformation branch and the temperature corresponding branch correspond to the low-frequency, medium-frequency and high-frequency resonant frequencies of the combined patch antenna sensor respectively.

[0049] When the structure is deformed, the transverse connector 6 pasted on the structural surface 8 near the transverse direction moves, thereby driving the transverse deformation additional patch 2 fixed thereto to move, causing the transverse deformation corresponding branch 103 and the transverse deformation additional patch radiating patch 201 to produce relative displacement, causing the low-frequency resonant frequency of the combined patch antenna sensor to change; when the longitudinal connector 7 pasted on the structural surface 8 near the longitudinal direction moves, thereby driving the longitudinal deformation additional patch 3 fixed thereto to move, causing the transverse deformation corresponding branch 103 and the longitudinal deformation additional patch radiating patch 301 to produce relative displacement, causing the medium-frequency resonant frequency of the combined patch antenna sensor to change.

[0050] When the external ambient temperature changes, the three resonant frequencies of the combined patch antenna sensor change. By calibrating the influence of temperature on the three resonant frequencies, the temperature is obtained by using the change in the high-frequency resonant frequency corresponding to the temperature corresponding branch 102, and then the accurate change in the low-frequency and medium-frequency resonant frequencies caused by the deformation is obtained through temperature compensation, thereby realizing the synchronous monitoring of the bidirectional deformation of the structure and the temperature.

[0051] The transverse connector 6 and the longitudinal connector 7 are made of non-metallic materials such as plastic or wood to reduce the impact on the electromagnetic signal of the sensor. The upper radiation patch and the lower radiation patch of the main patch antenna 1, the transverse deformation additional patch radiation patch 201 and the longitudinal deformation additional patch radiation patch 301 are all made of copper, and the main patch antenna dielectric substrate 105, the transverse deformation additional patch dielectric substrate 202 and the longitudinal deformation additional patch dielectric substrate 302 are all made of FR4.

[0052] When the monitoring system is working, the application software system 10 controls the scanning frequency interval and scanning frequency step of the reader 9. The reader 9 modulates the signal and transmits an inquiry signal to the sensor. The RF chip 4 of the sensor obtains energy from the inquiry signal for activation, and transmits an electromagnetic wave signal containing the antenna number and the antenna electrical characteristics to the reader 9. The reader 9 receives and demodulates the signal, and transmits the demodulated signal to the application software system 10 by wire. The application software system 10 processes the signal to obtain the change of the sensor resonant frequency, and stores the received and processed RF signal.

[0053] The resonant frequency of the combined patch antenna sensor is related to the working characteristics of the RF chip 4, that is, the frequency point corresponding to the minimum power of the reader 9 to activate the RF chip 4 and the maximum power emitted by the reader 9 to receive the RF chip 4 can be equivalent to the resonant frequency of the sensor. Therefore, the signal strength sent and received by the reader 9 can be processed by the application software system 10 to determine the resonant frequency of the sensor, thereby determining the bidirectional deformation and temperature of the structural surface 8.

[0054] The change in the low-frequency resonant frequency of the sensor is related to the relative displacement and temperature between the lateral deformation additional patch 2 and the main patch antenna 1, the change in the intermediate-frequency resonant frequency of the sensor is related to the relative displacement and temperature between the longitudinal deformation additional patch 3 and the main patch antenna 1, and the change in the high-frequency resonant frequency of the sensor is only related to the temperature, and there is a linear relationship between the temperature and the relative displacement and the change in the resonant frequency. Therefore, the bidirectional deformation and temperature of the structural surface 8 can be monitored by monitoring the low-frequency, intermediate-frequency and high-frequency resonant frequency offsets of the sensor.

[0055] The signal transmitted by the RF chip 4 contains a chip code, which can be identified by the application software system 10. When multiple sensors are arranged, the position of the corresponding sensor can be obtained by analyzing the chip code of the sensor, and the bidirectional deformation and temperature value of the structure measured by the sensor can be further obtained through the RF signal.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present application. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure, characterized in that: The invention comprises a main patch antenna (1), a transversely deformable additional patch (2), a longitudinally deformable additional patch (3), a radio frequency chip (4), a padding layer (5), a transverse connecting piece (6) and a longitudinal connecting piece (7); the padding layer (5) is adhesively connected to a structural surface (8) at the bottom and adhesively connected to the main patch antenna (1) at the top; one end of the transverse connecting piece (6) is adhesively connected to the structural surface (8) and the other end is fixedly connected to the transversely deformable additional patch (2); one end of the longitudinal connecting piece (7) is adhesively connected to the structural surface (8) and the other end is fixedly connected to the longitudinally deformable additional patch (3); the transversely deformable additional patch (2) and the longitudinally deformable additional patch (3) are in close contact with the main patch antenna (1) but are not fixedly connected and can generate relative displacement; the radio frequency chip (4) is connected to the main patch antenna (1).

2. According to claim 1, a bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure is characterized in that: The main patch antenna is composed of an upper radiating patch, a dielectric substrate (105), a lower radiating patch and a radio frequency chip (4); the feed line (101), the temperature corresponding branch (102), the lateral deformation corresponding branch (103) and the longitudinal deformation corresponding branch (104) are the upper radiating patch of the main patch antenna (1); the radio frequency chip (4) is welded on the feed line (101); the ground plane (106) is the lower radiating patch of the main patch antenna (1); and the lateral deformation corresponding branch (103) adopts a bending design.

3. The bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure according to claim 1, characterized in that: The transverse deformation additional patch (2) is composed of a transverse deformation additional patch radiation patch (201) and a transverse deformation additional patch dielectric substrate (202); the transverse deformation additional patch radiation patch (201) is in close contact with a transverse deformation corresponding branch (103) of the main patch antenna (1); and the transverse deformation additional patch dielectric substrate (202) is fixedly connected to one end of a transverse connector (6).

4. The bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure according to claim 1, characterized in that: The longitudinal deformation additional patch (3) is composed of a longitudinal deformation additional patch radiation patch (301) and a longitudinal deformation additional patch dielectric substrate (302); the longitudinal deformation additional patch radiation patch (301) is in close contact with a longitudinal deformation corresponding branch (104) of the main patch antenna (1); and the longitudinal deformation additional patch dielectric substrate (302) is fixedly connected to one end of a longitudinal connector (7).

5. A method for monitoring using a bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure according to any one of claims 1 to 4, characterized in that: When the structural surface is deformed, the transverse connecting member (6) and the longitudinal connecting member (7) connected to the structural surface will deform transversely and longitudinally: The lateral deformation drives the lateral deformation additional patch (2) and the main patch antenna (1) to cause lateral relative displacement, thereby changing the equivalent length of the corresponding branch of the multi-frequency combined antenna, causing one of the resonant frequencies of the multi-frequency combined patch antenna to change; The longitudinal deformation drives the longitudinal deformation additional patch (3) and the main patch antenna (1) to cause longitudinal relative displacement, thereby changing the equivalent length of the multi-frequency combined antenna and its corresponding branch, causing another resonant frequency of the multi-frequency combined patch antenna to change. By monitoring the change in the corresponding branch resonant frequency, the monitoring of the bidirectional deformation of the structure is achieved.

6. The monitoring method according to claim 5, characterized in that: The sensor has three resonant frequencies, which correspond to the three branches of the antenna respectively. The movement of the additional patches for lateral and longitudinal deformation only changes the resonant frequency of the corresponding branches, but does not affect the resonant frequencies corresponding to other branches. Therefore, the two branches of the sensor affect the two resonant frequencies through the movement of the additional patches, which are used to monitor the bidirectional strain of the structure. Since there is no external additional patch on the remaining branch, the factor affecting the resonant frequency of the branch is temperature. By measuring the resonant frequency of the branch corresponding to the temperature, the surface temperature of the structure can be monitored.

7. The monitoring method according to claim 5, characterized in that: When the structure undergoes bidirectional deformation and temperature changes, three resonant frequencies are used for monitoring and decoupling. The temperature is monitored through one of the resonant frequencies, and the other two resonant frequencies are corrected through temperature compensation to achieve accurate monitoring of the bidirectional deformation of the structure. When the measured resonant frequency changes of the three branches are Δf 102 , Δf 103 and Δf 104 , and the corresponding relationship between temperature change ΔT, lateral deformation and longitudinal deformation is: ΔT = k 102温 Δf 102 , ΔL 横 =k 103形 (Δf 103 -ΔT / k 103温 ), ΔL 纵 =k 104形 (Δf 104 -ΔT / k 104温 ), where k 102温 , k 103温 and k 104温 are the corresponding relationships between the resonant frequency change and the temperature change of the branch (102) corresponding to the temperature, the branch (103) corresponding to the lateral deformation, and the branch (104) corresponding to the longitudinal deformation obtained by calibration before installation, k 103形 With k 104形 The corresponding relationship between the resonant frequency change and the deformation of the branch (103) corresponding to the lateral deformation and the branch (104) corresponding to the longitudinal deformation obtained by calibration before installation can realize the synchronous monitoring of the structural temperature and the bidirectional deformation through the corresponding formula.

8. A bidirectional deformation and temperature monitoring system based on a multi-frequency combined patch antenna structure, characterized in that: It comprises a bidirectional deformation and temperature sensor based on a multi-frequency combined patch antenna structure, a reader (9) and an application software system (10) as described in any one of claims 1 to 4.

9. The bidirectional deformation and temperature monitoring system based on a multi-frequency combined patch antenna structure according to claim 8, characterized in that: The reader (9) is composed of a radio frequency signal transceiver module, a control module and a modulation and demodulation module.

10. The bidirectional deformation and temperature monitoring system based on a multi-frequency combined patch antenna structure according to claim 8, characterized in that: The application software system (10) is composed of a control module, a data processing module and a data storage module. The reader (9) and the sensor wirelessly transmit signals via electromagnetic wave signals. The reader (9) is connected to the application software system (10) to perform data transmission.

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