阅读说明：本技术 一种基于贴片天线的无源无线倾斜监测装置 (Passive wireless inclination monitoring device based on patch antenna ) 是由 谢丽宇 郑志泉 薛松涛 于 2021-06-30 设计创作，主要内容包括：本发明涉及一种基于贴片天线的无源无线倾斜监测装置,包括标签和阅读器,标签包括固定组件和活动组件,活动组件包括第一介质板以及设置在第一介质板上的第一贴片,固定组件包括第二贴片、第二介质板、微带馈电线、芯片和地平面,第二贴片、微带馈电线和芯片依次连接,且设于第二介质板其中一侧表面上,地平面设于第二介质板另一侧表面上,第一贴片和第二贴片的形状为扇环形,第二贴片和第二介质板面对面同心设置,第一介质板绕第二贴片圆心转动设置在第二介质板上,标签竖直设置在被测物上。与现有技术相比,本发明实现了无线无源检测,结构简单,安装简便,受外界干扰小,使用寿命长,成本低,可准确定位。(The invention relates to a passive wireless inclination monitoring device based on a patch antenna, which comprises a tag and a reader, wherein the tag comprises a fixed component and a movable component, the movable component comprises a first dielectric plate and a first patch arranged on the first dielectric plate, the fixed component comprises a second patch, a second dielectric plate, a microstrip feed line, a chip and a ground plane, the second patch, the microstrip feed line and the chip are sequentially connected and arranged on one side surface of the second dielectric plate, the ground plane is arranged on the other side surface of the second dielectric plate, the first patch and the second patch are in fan-ring shapes, the second patch and the second dielectric plate are arranged in a face-to-face concentric mode, the first dielectric plate is rotatably arranged on the second dielectric plate around the circle center of the second patch, and the tag is vertically arranged on a measured object. Compared with the prior art, the wireless passive detection device has the advantages of wireless passive detection, simple structure, convenience in installation, small interference from the outside, long service life, low cost and capability of accurate positioning.)

1. The passive wireless inclination monitoring device based on the patch antenna is characterized by being used for measuring the inclination of a measured object (2), and comprising a tag (1) and a reader (3), wherein the tag (1) comprises a fixed component and a movable component, the movable component comprises a first dielectric plate (4) and a first patch (5) arranged on the first dielectric plate (4), the fixed component comprises a second patch (6), a second dielectric plate (7), a microstrip feed line (8), a chip (9) and a ground plane (12), the second patch (6), the microstrip feed line (8) and the chip (9) are sequentially connected and arranged on one side surface of the second dielectric plate (7), the ground plane (12) is arranged on the other side surface of the second dielectric plate (7), and the first patch (5) and the second patch (6) are fan-shaped, the second patch (6) and the second dielectric slab (7) are concentrically arranged face to face, the first dielectric slab (4) is rotatably arranged on the second dielectric slab (7) around the circle center of the second patch (6), and the label (1) is vertically arranged on the object to be tested (2);

the reader (3) measures the resonant frequency of the tag (1) and calculates the inclination angle of the measured object (2) according to the drift amount of the resonant frequency.

2. A passive wireless tilt monitoring device based on patch antenna according to claim 1, characterized in that the inner and outer arc radii of the first patch (5) are the same as the inner and outer arc radii of the second patch (6), respectively.

3. The passive wireless tilt monitoring device based on the patch antenna according to claim 2, wherein the tilt angle of the object to be measured (2) is calculated by the following formula:

wherein, Delta theta is the inclination angle of the measured object (2), c is the light speed in vacuum, epsilon is the relative dielectric constant of the second dielectric plate (7), and L₂Is the circumferential length of the midline, L, of the first patch (5)₄Is the circumferential length of the midline, L, of the second patch (6)₀Is the initial circumferential overlap length of the midline of the first patch (5) and the second patch (6), and R is the radius of the midline of the first patch (5) and the second patch (6).

4. The passive wireless tilt monitoring device based on the patch antenna according to claim 1, wherein the second dielectric plate (7) is annular.

5. A passive wireless tilt monitoring device based on patch antenna according to claim 4, characterized in that the second dielectric plate (7) and the second patch (6) are concentrically arranged.

6. The passive wireless tilt monitoring device based on a patch antenna according to claim 1, wherein the first dielectric plate (4) is fan-shaped.

7. A passive wireless tilt monitoring device based on a patch antenna according to claim 6, characterized in that the first dielectric plate (4) and the first patch (5) are concentrically arranged.

8. The passive wireless inclination monitoring device based on the patch antenna is characterized by further comprising a pin (11), wherein a fixing ring (10) is arranged at the circle center end of the first dielectric plate (4), and the pin (11) penetrates through the fixing ring (10) and is inserted into an object to be detected (2) during detection.

9. A passive wireless tilt monitoring device based on a patch antenna according to claim 1, characterized in that the material of the first patch (5), the second patch (6), the microstrip feed line (8) and the ground plane (12) is brass.

10. The passive wireless tilt monitoring device based on the patch antenna according to claim 1, wherein the material of the first dielectric plate (4) and the second dielectric plate (7) is RT 5880.

Technical Field

The invention relates to the field of structural health monitoring, in particular to a passive wireless inclination monitoring device based on a patch antenna.

Background

In the field of structural health monitoring, the inclination angle is an important parameter for building health monitoring. Currently common tilt sensors can be classified into mechanical, electronic, and fiber optic.

The mechanical tilt sensor has the advantages of easy design, low cost, reliable performance, intuitive measured data and the like, but the mechanical tilt sensor has limited application range and small measurement range, is difficult to be connected with a network, and is difficult to realize real-time monitoring. The electronic sensor and the optical fiber sensor have the advantages of high integration level, high precision and easiness in network connection, and can realize remote and real-time monitoring of building inclination. However, both the electronic sensor and the optical fiber sensor require a connecting wire or an optical fiber to obtain energy or transmit signals, and therefore, when a large number of measuring points are provided, wiring is difficult, and when a disaster occurs, the wiring is easily broken, resulting in failure of the sensor.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, and provides a passive wireless inclination monitoring device based on a patch antenna, which realizes wireless passive detection, has the advantages of simple structure, simple and convenient installation, small external interference, long service life, low cost and accurate positioning.

The purpose of the invention can be realized by the following technical scheme:

a passive wireless inclination monitoring device based on a patch antenna is used for measuring the inclination of a measured object and comprises a tag and a reader, the label comprises a fixed component and a movable component, the movable component comprises a first medium plate and a first patch arranged on the first medium plate, the fixed component comprises a second paster, a second dielectric plate, a micro-strip feeder line, a chip and a ground plane, the second paster, the micro-strip feeder line and the chip are connected in sequence, and is arranged on one side surface of the second dielectric plate, the ground plane is arranged on the other side surface of the second dielectric plate, the first patch and the second patch are in fan-shaped ring shapes, the second patch and the second dielectric slab are concentrically arranged face to face, the first dielectric slab is arranged on the second dielectric slab in a rotating mode around the circle center of the second patch, and the label is vertically arranged on the object to be tested;

when the first patch and the second patch are in an overlapped state, subtracting the length of the overlapped part of the circumferential length of the first patch and the circumferential length of the second patch from the sum of the circumferential length of the first patch and the circumferential length of the second patch to obtain the resonant length of the patch antenna, and when the first patch and the second patch are not overlapped any more, the resonant length of the patch antenna is the circumferential length of the second patch;

the reader transmits electromagnetic wave signals to the tag at different frequencies, when the power of signals received by the tag reaches a threshold value, the chip can be activated, the minimum transmitting frequency of the reader required by the activation of the chip is related to the frequency of the signals transmitted by the reader, the first patch and the second patch form a patch antenna, when the reader transmits the signals at the resonant frequency of the patch antenna, the transmitting power required by the activation of the chip is minimum, and the resonant frequency of the patch antenna in the tag can be determined by searching the transmitting frequency which enables the minimum transmitting power to reach the minimum value;

the movable assembly can rotate freely, and a connecting line between the center of a circle and the center of gravity of the movable assembly is kept vertical all the time under the action of gravity, so that the first patch and the second patch can rotate relatively due to the inclination of the object to be tested, the overlapping degree is changed, the resonance length of the patch antenna is changed, the resonance frequency of the patch antenna is further caused to drift, the drift amount and the inclination angle of the resonance frequency of the patch antenna have a definite relation in a fixed range, the inclination angle change of the object to be tested is obtained according to the resonance frequency change of the patch antenna, and the inclination monitoring of the object to be tested is realized;

the inclination monitoring device can sense inclination angle change and can simultaneously realize wireless detection, the inclination monitoring device can be activated through electromagnetic waves without an additional power supply to realize passive detection, the chip stores the label number and the position information of the patch antenna, after the chip is activated, the patch antenna in the label can generate current and emit an electromagnetic wave signal with the label number and the position information, and the signal is received and processed by a reader to obtain the position and the inclination state information of a detected object;

the inclination monitoring device has the advantages of simple structure, small volume, long service life, simple and convenient installation and low manufacturing cost.

Furthermore, the inner arc radius and the outer arc radius of the first patch are respectively the same as the inner arc radius and the outer arc radius of the second patch.

Further, the calculation formula of the inclination angle of the measured object is as follows:

wherein, Delta theta is the inclination angle of the object to be measured, c is the light speed in vacuum, epsilon is the relative dielectric constant of the second dielectric plate, and L₂Is the circumferential length of the midline of the first patch, L₄Is the circumferential extent of the midline of the second patch, L₀Is the initial circumferential overlap length of the midline of the first and second patches, and R is the radius of the midline of the first and second patches.

Further, the second dielectric plate is annular.

Further, the second dielectric plate and the second patch are concentrically arranged.

Furthermore, the first dielectric plate is fan-shaped.

Furthermore, the first dielectric plate and the first patch are concentrically arranged, so that the mounting is simple and convenient, and the first patch and the second patch are ensured to relatively rotate around the same circle center.

Further, the detection device also comprises a pin, wherein a fixing ring is arranged at the circle center end of the first medium plate, and the pin penetrates through the fixing ring and is inserted into a detected object during detection, so that the detection device is simple and convenient to mount.

Further, the first patch, the second patch, the microstrip feed line and the ground plane are made of brass.

Further, the material of the first dielectric plate and the second dielectric plate is RT 5880.

Compared with the prior art, the invention has the following beneficial effects:

(1) the invention is characterized in that a label is vertically arranged on a tested object, a first patch and a second patch form a patch antenna, a reader transmits electromagnetic wave signals to the label at different frequencies, when the signal power received by the label reaches a threshold value, a chip can be activated, the first patch and the second patch can relatively rotate due to the inclination of the tested object, so that the resonance length of the patch antenna changes, and further the resonance frequency of the patch antenna shifts, the resonance frequency of the patch antenna in the label can be determined by searching the transmission frequency which enables the minimum transmission power to reach the minimum value, the inclination angle change of the tested object can be obtained according to the resonance frequency change of the patch antenna, thereby realizing the inclination monitoring of the tested object, the inclination angle monitoring device of the invention converts the inclination angle information of the tested object into the electromagnetic wave signals, does not need an additional power supply, and realizes wireless passive detection, the inclination monitoring device is simple in structure, simple and convenient to install, small in interference from the outside, long in service life and low in manufacturing cost, and the inclination monitoring cost is reduced;

(2) the chip stores the label number and the position information of the patch antenna, after the chip is activated, the patch antenna in the label can generate current and emit an electromagnetic wave signal with the label number and the position information, and the signal is received and processed by a reader to obtain the position and the inclination state information of a measured object;

(3) the second dielectric plate is annular, the second dielectric plate and the second patch are concentrically arranged, the first dielectric plate is fan-shaped, the first dielectric plate and the first patch are concentrically arranged, the installation is simple and convenient, and the first patch and the second patch are ensured to relatively rotate around the same circle center.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of a tag structure;

FIG. 3 is a schematic structural view of a fixing assembly;

FIG. 4 is a schematic structural view of a second dielectric plate;

FIG. 5 is a schematic view of the location of the ground plane;

FIG. 6 is a schematic view of a movable assembly;

FIG. 7 is a schematic structural view of a first dielectric plate;

the reference numbers in the figures illustrate:

1. the tag comprises a tag, 2, an object to be tested, 3, a reader, 4, a first dielectric plate, 5, a first patch, 6, a second patch, 7, a second dielectric plate, 8, a microstrip feeder, 9, a chip, 10, a fixed ring, 11, a pin and 12, a ground plane.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

A passive wireless inclination monitoring device based on a patch antenna is used for measuring the inclination of a measured object 2, and comprises a tag 1 and a reader 3, as shown in figure 1, figure 2, figure 3, figure 4, figure 5, figure 6 and figure 7, wherein the tag 1 comprises a fixed component and a movable component, the movable component comprises a first dielectric plate 4 and a first patch 5 arranged on the first dielectric plate 4, the fixed component comprises a second patch 6, a second dielectric plate 7, a microstrip feeder line 8, a chip 9 and a ground plane 12, the second patch 6, the microstrip feeder line 8 and the chip 9 are sequentially connected and arranged on one side surface of the second dielectric plate 7, the ground plane 12 is arranged on the other side surface of the second dielectric plate 7, the first patch 5 and the second patch 6 are fan-shaped, the second patch 6 and the second dielectric plate 7 are concentrically arranged face to face, the first dielectric plate 4 is arranged on the second dielectric plate 7 in a rotating mode around the circle center of the second patch 6, the label 1 is vertically arranged on the object to be tested 2;

the reader 3 transmits electromagnetic wave signals to the tag 1 at different frequencies, when the power of signals received by the tag 1 reaches a threshold value, the chip 9 can be activated, the minimum transmitting frequency of the reader required for activating the chip 9 is related to the frequency of the signals transmitted by the reader, the first patch 5 and the second patch 6 form a patch antenna, when the reader transmits the signals at the resonant frequency of the patch antenna, the transmitting power required for activating the chip 9 is the minimum, and the resonant frequency of the patch antenna in the tag 1 can be determined by searching the transmitting frequency which enables the minimum transmitting power to reach the minimum;

the movable assembly can rotate freely, and a connecting line between the center of a circle and the center of gravity of the movable assembly is kept vertical all the time under the action of gravity, so that the first patch 5 and the second patch 6 can rotate relatively due to the inclination of the object to be measured 2, the overlapping degree is changed, the resonance length of the patch antenna is changed, the resonance frequency of the patch antenna is further caused to drift, the drift amount and the inclination angle of the resonance frequency of the patch antenna have a definite relation in a fixed range, the inclination angle change of the object to be measured is obtained according to the resonance frequency change of the patch antenna, and the inclination monitoring of the object to be measured is realized;

the inclination monitoring device can sense inclination angle change and can simultaneously realize wireless detection, the inclination monitoring device can be activated through electromagnetic waves without an additional power supply to realize passive detection, the chip stores ID and position information of the patch antenna, after the chip is activated, the patch antenna in the tag can generate current and emit an electromagnetic wave signal with tag number and position information, and after the signal is received and processed by a reader, the position and inclination state information of a detected object can be obtained;

the inclination monitoring device is simple in structure and low in manufacturing cost.

The inner and outer arc radii of the first patch 5 are the same as the inner and outer arc radii of the second patch 6, respectively.

The calculation formula of the inclination angle of the measured object 2 is as follows:

wherein, Delta theta is the inclination angle of the measured object 2, c is the light speed in vacuum, epsilon is the relative dielectric constant of the second dielectric plate 7, and L₂Is the circumferential extent of the midline, L, of the first patch 5₄Is the circumferential extent of the midline, L, of the second patch 6₀To complete the initial circumferential overlap length of the midline of the first patch 5 and the second patch 6 upon installation, R is the radius of the midline of the first patch 5 and the second patch 6.

The second dielectric slab 7 is annular, and second dielectric slab 7 and second paster 6 set up with one heart, and first dielectric slab 4 is fan-shaped, and first dielectric slab 4 and first paster 5 set up with one heart, and the simple installation guarantees simultaneously that first paster 5 and second paster 6 rotate around same centre of a circle relatively.

The inclination monitoring device further comprises a pin 11, a fixing ring 10 is arranged at the circle center end of the first medium plate 4, the pin 11 penetrates through the fixing ring 10 during detection, and is inserted into the object to be detected 2, and the inclination monitoring device is simple and convenient to install.

The material of the first patch 5, the second patch 6, the microstrip feed line 8 and the ground plane 12 is brass and the material of the first dielectric plate 4 and the second dielectric plate 7 is RT 5880.

This embodiment has provided a passive wireless slope monitoring devices based on patch antenna, first patch 5 and second patch 6 constitute a patch antenna, the resonance frequency that the slope of testee 2 can arouse patch antenna takes place to drift, reader 3 takes place to drift through detecting resonance frequency, calculate the inclination change of testee 2, realize wireless passive monitoring, slope monitoring devices simple structure, simple installation, it is little disturbed by the external world, long service life, the cost of manufacture is low simultaneously, the cost of slope monitoring has been reduced.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.