Anti-interference wireless passive temperature measurement system based on RFID

Abstract

The invention relates to an anti-interference wireless passive temperature measurement system based on a radio frequency identification (RFID) technology. The anti-interference wireless passive temperature measurement system comprises a temperature sensor and a reader antenna. The temperature sensor comprises a sensor antenna, and the sensor antenna is a linearly polarized antenna. The reader antenna is a circularly polarized antenna and is in communication connection with the temperature sensor. The sensor antenna and the reader antenna transmit and receive signals by using broadband. According to the anti-interference wireless passive temperature measurement system, the temperature data of the detected object in the operation process can be accurately monitored and obtained in real time, the frequency band requirements of different areas can be met, the influence of frequency band deviation caused by the environment can be reduced by adopting broadband signal receiving and transmitting, and the anti-interference wireless passive temperature measurement system has the advantages of being simple in structure and convenient to use. The antenna is not sensitive to the direction of the position where the temperature sensor is placed, and high gain of the reader antenna is achieved.

Description

Technical Field

[0001] The present application relates to the field of wireless monitoring technology, and in particular to an anti-interference wireless passive temperature measurement system based on RFID. Background Art

[0002] Generally, the bearing fault is diagnosed by obtaining the bearing temperature data. However, it is often difficult to measure the temperature of a bearing in working state. In the related art, the bearing temperature measurement system includes: wired temperature measurement system, wireless temperature measurement system with active sensor and wireless temperature measurement system with passive sensor.

[0003] For wired temperature measurement systems, the installation and wiring of the system are complicated and not suitable for temperature measurement of high-speed rotating bearings at high speeds. For active sensors, the battery needs to be replaced after it is exhausted before it can be used, or a self-powered module needs to be designed. Due to the need for a battery module, the sensor is larger in size, which has a certain impact on the operation of high-speed bearings and is costly. For passive sensors, due to the lack of batteries, the sensitivity is higher, and the performance of wireless temperature measurement systems with passive sensors is more easily affected by the complexity of the environment (oil, metal, high-speed rotation, etc.) and the direction of the sensor antenna placement, making the energy received by the passive sensor insufficient to complete the temperature measurement.

[0004] In addition, a wireless passive temperature measurement system based on radio frequency identification (RFID) technology can also be used, but the available frequency bands in different regions are different. The wireless passive temperature measurement system needs to be designed for different regions and carrying application scenarios, which will increase the R&D cost. Summary of the invention

[0005] In order to overcome the problems existing in the related art, the present application provides an RFID-based anti-interference wireless passive temperature measurement system for bearings.

[0006] According to an embodiment of the present application, the present application provides an anti-interference wireless passive temperature measurement system based on radio frequency identification technology (RFID), which includes: a temperature sensor and a reader antenna. The temperature sensor includes a sensor antenna, and the sensor antenna is a linearly polarized antenna. The reader antenna is a circularly polarized antenna and is communicatively connected to the temperature sensor. Wherein, the sensor antenna and the reader antenna both use a wideband to transmit and receive signals.

[0007] In some embodiments, the sensor antenna and the reader antenna are both patch antennas.

[0008] In some embodiments, the sensor antenna includes: a radiation unit and a parasitic patch. The radiation unit includes an integrated slot, and the chip is integrated into the integrated slot. The parasitic patch is used to increase the signal bandwidth.

[0009] In some embodiments, the sensor antenna further comprises an adjustment slot, wherein the adjustment slot is rectangular and is disposed adjacent to the integrated slot to adjust the impedance conjugated with the chip.

[0010] In some embodiments, the reader antenna includes: a parasitic patch layer and a driving patch layer. A circular polarization slot is provided on the surface of the parasitic patch layer for circular polarization of the reader antenna. An expansion slot is provided on the surface of the driving patch layer for expanding the frequency bandwidth of the signal of the reader antenna. The parasitic patch layer and the driving patch layer are stacked in the thickness direction.

[0011] In some embodiments, the circular polarization slot is a cross-shaped structure formed by the intersection of mutually perpendicular transverse slots and longitudinal slots.

[0012] In some embodiments, the expansion slot portion is in a square frame shape.

[0013] In some embodiments, the reader antenna further comprises a reader antenna housing to prevent foreign matter from entering the interior of the reader antenna.

[0014] In some embodiments, the sensor antenna is a patch antenna comprising a high dielectric constant material.

[0015] In some embodiments, the anti-interference wireless passive temperature measurement system further includes: a reader, a coaxial cable, a processing terminal and a Zigbee module. The coaxial cable is used to electrically connect the reader and the reader antenna; the Zigbee module is electrically connected to the processing terminal; and the Zigbee module is used to wirelessly receive the data information collected by the reader and transmit it to the processing terminal.

[0016] The technical solution provided by the embodiments of the present application may include the following beneficial effects: Through the anti-interference wireless passive temperature measurement system of the present application, the temperature data of the detected object during operation can be monitored and obtained in real time and accurately, and the frequency band requirements of different regions can be met. The circularly polarized antenna does not need to be aligned with the polarization of the sensor antenna. The circularly polarized antenna can reduce the system's sensitivity to the orientation of the sensor antenna, and can effectively avoid the loss caused by polarization mismatch. It has a small size, a simple structure, and a flexible design, which reduces R&D costs. In addition, the use of wide-band receiving and transmitting signals can reduce the impact of frequency band offset caused by the environment, is insensitive to the direction of the location where the temperature sensor is placed, and achieves high gain of the reader antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of an RFID-based anti-interference wireless passive temperature measurement system according to an embodiment of the present application is shown;

[0019] Figure 2 shows a top view of a sensor antenna according to an embodiment of the present application;

[0020] Figure 3 shows a side view of a reader antenna according to an embodiment of the present application;

[0021] Figure 4 A top view of a parasitic patch layer according to an embodiment of the present application is shown; and

[0022] Figure 5 A top view of a driving patch layer according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme of the embodiment of the present application will be clearly and completely described below in conjunction with the drawings of the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, not all of the embodiments. Based on the described embodiment of the present application, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of this application.

[0024] According to an embodiment of the present application, an RFID-based anti-interference wireless passive temperature measurement system 100 is provided. The anti-interference wireless passive temperature measurement system 100 is used to monitor the temperature data of the detected object during operation to diagnose the monitored object. For example, the anti-interference wireless passive temperature measurement system 100 can be, but is not limited to, monitoring the temperature data of the bearing 70 during operation.

[0025] Figure 1 FIG. 1 is a schematic diagram of an RFID-based anti-interference wireless passive temperature measurement system 100 according to an embodiment of the present application. Figure 1 As shown, the RFID-based anti-interference wireless passive temperature measurement system 100 includes a temperature sensor 10 , a reader antenna 20 , a coaxial cable 40 , a reader 30 , a Zigbee module 60 and a processing terminal 50 .

[0026] The reader 30 is electrically connected to the reader antenna 20 via a coaxial cable 40. The Zigbee module 60 is electrically connected to the processing terminal 50. The Zigbee module 60 is used to wirelessly receive the data information collected by the reader 30 and transmit it to the processing terminal 50.

[0027] The reader 30 and the tag perform contactless data communication to achieve the purpose of identifying the target. The basic working principle of the RFID-based anti-interference wireless passive temperature measurement system 100 is as follows: the reader 30 sends a radio frequency signal of a specific frequency through the reader antenna 20. When the electronic tag from the temperature sensor 10 enters the effective working area, an induced current is generated, thereby obtaining energy and being activated, so that the electronic tag transmits its own coded information through the sensor antenna 11; the reader antenna 20 receives the modulated signal sent from the tag, and transmits it to the signal processing module of the reader 30 through the modulator of the reader antenna 20. After demodulation and decoding, the effective information is transmitted to the processing terminal 50 through the Zigbee module 60 for related processing; the processing terminal 50 identifies the identity of the tag according to logical operations, and makes corresponding processing and control for different settings.

[0028] Specifically, see Figure 1 As shown, the temperature sensor 10 can be fixed on the inner wall of the inner ring or the outer wall of the outer ring of the bearing 70, or the end face of the inner ring or the outer ring, and rotate with the bearing 70. The temperature sensor 10 includes a temperature measuring chip (not shown in the figure) and a sensor antenna 11, and the temperature measuring chip is integrated on the sensor antenna 11.

[0029] The temperature sensor 10 is a wireless passive sensor. Compared with an active sensor, it does not require additional batteries or cables to power the temperature sensor 10, and reduces the use of cables and avoids complicated wiring. Therefore, it is more suitable for the working environment of the bearing 70. In addition, the wireless passive sensor does not need to install batteries, which reduces the weight and volume of the battery, has little impact on the operation of the bearing 70, is easy to install, and does not need to worry about running out of power, avoiding frequent battery replacement.

[0030] Furthermore, the reader antenna 20 is wirelessly connected to the sensor antenna 11, and the reader antenna 20 is used to radiate or transmit radio frequency signals. The reader 30 transmits a radio frequency signal (also known as electromagnetic wave, radio wave) energy of a specific frequency to the temperature sensor 10 to drive the temperature sensor 10 to send out its internal signal or data.

[0031] Specifically, the sensor antenna 11 generates an induced current by receiving the radio frequency signal emitted by the reader antenna 20 , thereby providing sufficient energy for the temperature measuring chip in a short period of time during the rotation temperature measurement, so that the temperature measuring chip transmits the temperature signal to the reader antenna 20 .

[0032] In some embodiments, the anti-interference wireless passive temperature measurement system 100 includes: a temperature sensor 10 and a reader antenna 20. The temperature sensor 10 includes a sensor antenna 11, and the sensor antenna 11 is a linearly polarized antenna. The reader antenna 20 is a circularly polarized antenna and is communicatively connected to the temperature sensor 10. The sensor antenna 11 and the reader antenna 20 both use a wideband to transmit and receive signals.

[0033] Specifically, the sensor antenna 11 is a linearly polarized antenna. The size of the RF signal sensed by the linearly polarized antenna is related to the polarization direction of the transceiver antenna, that is, when the polarization directions of the transceiver antenna are consistent, the polarization loss is minimal. The linearly polarized antenna can be installed vertically, horizontally or on any other plane, and can receive RF signals.

[0034] In addition, the reader antenna 20 is a circularly polarized antenna. The radio frequency signal transmitted or received by the circularly polarized antenna is independent of the polarization direction of the sensor antenna 11. The circularly polarized antenna does not need to be polarized and aligned with the sensor antenna 11. The circularly polarized antenna can reduce the system's sensitivity to the orientation of the sensor antenna 11 and can effectively avoid losses caused by polarization mismatch.

[0035] In addition, the sensor antenna 11 and the reader antenna 20 both use wideband to transmit and receive signals. In the working environment where the bearing 70 operates, there are impurities such as lubricating oil and metal chips, which may reduce the frequency band of the sensor antenna 11 and the reader antenna 20. Therefore, the use of wideband to transmit and receive signals can reduce the influence of impurities such as lubricating oil and metal chips on the frequency band of the transmitted and received signals, and realize the anti-interference function of the anti-interference wireless passive temperature measurement system 100 against the external environment.

[0036] In some embodiments, the sensor antenna 11 and the reader antenna 20 are both patch antennas.

[0037] Specifically, the antenna type of the sensor antenna 11 can be a microstrip patch antenna, which can resist interference from metal chips and the like, and realize dual-band by cutting grooves on the radiation surface of the sensor antenna 11, thereby facilitating the realization of dual-frequency.

[0038] In some embodiments, Figure 2 FIG. 1 shows a top view of the sensor antenna 11 according to an embodiment of the present application. Figure 2As shown, the sensor antenna 11 includes: a radiation unit 12 and a parasitic patch 13. The radiation unit 12 includes an integrated slot 121, and a chip can be integrated into the integrated slot 121. The parasitic patch 13 is used to increase the signal bandwidth. In addition, the sensor antenna 11 may also include a sensor antenna housing 14 to prevent impurities from entering the sensor antenna 11.

[0039] Furthermore, in some embodiments, the sensor antenna 11 may further include: an adjustment slot 122. The adjustment slot 122 may be disposed adjacent to the integrated slot 121 to adjust the impedance conjugated with the chip.

[0040] Specifically, the adjustment groove portion 122 may be rectangular, and impedance matching (also called conjugate matching) with the temperature measurement chip is achieved by adjusting the length and / or width of the adjustment groove portion 122 .

[0041] In addition, the sensor antenna 11 may be made of a high dielectric constant material, so that the sensor antenna 11 may be miniaturized.

[0042] In some embodiments, the reader antenna 20 is a patch antenna. The reader antenna 20 includes: a parasitic patch layer 21 and a driving patch layer 22. In other embodiments, the reader antenna 20 may further include a reader antenna housing 23 to prevent impurities from entering the interior of the reader antenna 20.

[0043] Figure 3 shows a side view of a reader antenna 20 according to an embodiment of the present application; Figure 4 shows a top view of a parasitic patch layer 21 according to an embodiment of the present application; and, Figure 5 FIG. 2 shows a top view of the driving patch layer 22 according to an embodiment of the present application. Figure 3-5 As shown, the parasitic patch layer 21 and the driving patch layer 22 are stacked in the thickness direction. A circular polarization slot 211 is provided on the surface of the parasitic patch layer 21 for circular polarization of the reader antenna 20; and an expansion slot 221 is provided on the surface of the driving patch layer 22 for expanding the frequency bandwidth of the signal of the reader antenna 20.

[0044] Specifically, in some embodiments, the circular polarization slot 211 is a structure formed by the intersection of a transverse slot 211a and a longitudinal slot 211b that are perpendicular to each other, that is, Figure 4 As shown, the circular polarization slot 211 is in a cross shape. The circular polarization slot 211 may also be in other shapes, which are not limited here. In this way, the parasitic patch layer 21 can be used to expand the bandwidth of the reader antenna 20 and improve the gain of the reader antenna 20.

[0045] In addition, the expansion slot portion 221 is in a square shape, that is, Figure 5 As shown, the expansion slot portion 221 is a square shape formed by four linear slots. In this way, the driving patch layer 22 can also be used to expand the frequency bandwidth of the reader antenna 20.

[0046] In some embodiments, Figure 1 As shown, the Zigbee module 60 is electrically connected to the processing terminal 50. The Zigbee module 60 is used to wirelessly receive the data signal collected and transmitted by the reader 30, and transmit the data signal to the processing terminal 50 for data processing in a wired or wireless manner.

[0047] Among them, the Zigbee module 60 is a new technology for deploying wireless sensor networks, which belongs to a communication protocol and can perform short-distance, low-rate wireless data transmission. In some other embodiments, other wireless communication protocols can also be used between the processing terminal 50 and the reader 30, which are not listed here one by one.

[0048] It should be noted that the present application aims to improve the bandwidth of the anti-interference wireless passive temperature measurement system 100 to achieve the anti-interference capability of the anti-interference wireless passive temperature measurement system 100 against the external environment. In addition, the present application can also be applied to the temperature monitoring of other components to be diagnosed, not limited to the bearing 70 shown in the embodiment.

[0049] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and embodiments are only considered as exemplary, and the true scope and spirit of the present application are indicated by the following scope of rights.

[0050] It should be understood that the present application is not limited to the precise structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the scope of the appended claims.

[0051] Reference numerals list

[0052] 100. Anti-interference wireless passive temperature measurement system;

[0053] 10. Temperature sensor; 11. Sensor antenna; 12. Radiating unit; 121. Integrated slot; 122. Adjustment slot; 13. Parasitic patch; 14. Sensor antenna housing;

[0054] 20. Reader antenna; 21. Parasitic patch layer; 211. Circular polarization slot; 211a. Transverse slot; 211b. Longitudinal slot; 22. Drive patch layer; 221. Extension slot; 23. Reader antenna housing;

[0055] 30. Reader;

[0056] 40. Coaxial cable;

[0057] 50. Processing terminal;

[0058] 60. Zigbee module;

[0059] 70. Bearings.

Claims

1. An anti-interference wireless passive temperature measurement system (100) based on radio frequency identification technology, characterized in that: include: A temperature sensor (10), comprising a sensor antenna (11), wherein the sensor antenna (11) is a linearly polarized antenna; as well as A reader antenna (20), which is a circularly polarized antenna and is communicatively connected to the temperature sensor (10); Wherein, the sensor antenna (11) and the reader antenna (20) both use a wide frequency band to transmit and receive signals.

2. The anti-interference wireless passive temperature measurement system (100) according to claim 1, characterized in that: The sensor antenna (11) and the reader antenna (20) are both patch antennas.

3. The anti-interference wireless passive temperature measurement system (100) according to claim 2, characterized in that: The sensor antenna (11) comprises: A radiation unit (12); comprising an integrated slot portion (121), wherein a chip is integrated into the integrated slot portion (121), and A parasitic patch (13) is used to increase the signal bandwidth.

4. The anti-interference wireless passive temperature measurement system (100) according to claim 3, characterized in that: The sensor antenna (11) further comprises: an adjustment slot portion (122); wherein the adjustment slot portion (122) is rectangular and is arranged adjacent to the integrated slot portion (121) and is used to adjust the impedance conjugated with the chip.

5. The anti-interference wireless passive temperature measurement system (100) according to claim 2, characterized in that: The reader antenna (20) comprises: A parasitic patch layer (21), the surface of which is provided with a circular polarization groove (211) for circular polarization of the reader antenna (20); and A driving patch layer (22) having an expansion slot (221) on its surface for expanding the frequency bandwidth of a signal of the reader antenna (20); The parasitic patch layer (21) and the driving patch layer (22) are stacked in a thickness direction.

6. The anti-interference wireless passive temperature measurement system (100) according to claim 5, characterized in that: The circular polarization groove portion (211) is a cross-shaped structure formed by the intersection of mutually perpendicular transverse groove portions (211a) and longitudinal groove portions (211b).

7. The anti-interference wireless passive temperature measurement system (100) according to claim 5, characterized in that: The expansion slot portion (221) is in a square frame shape.

8. The anti-interference wireless passive temperature measurement system (100) according to claim 5, characterized in that: The reader antenna (20) further comprises a reader antenna housing (23) to prevent foreign matter from entering the interior of the reader antenna (20).

9. The anti-interference wireless passive temperature measurement system (100) according to claim 1, characterized in that: The sensor antenna (11) is a patch antenna comprising a high dielectric constant material.

10. The anti-interference wireless passive temperature measurement system (100) according to claim 1, characterized in that: Also includes: Reader (30); A coaxial cable (40) for electrically connecting the reader (30) and the reader antenna (20); Processing terminal (50); as well as A Zigbee module (60) is electrically connected to the processing terminal (50), and the Zigbee module (60) is used to wirelessly receive data information collected by the reader (30) and transmit it to the processing terminal (50).

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