RFID-based liquid identification method, device and equipment, medium and program product

Abstract

The invention discloses a liquid identification method and device based on RFID, equipment, a medium and a program product, and relates to the technical field of material identification, and the method specifically comprises the steps: obtaining first information of a first tag measured by a radio frequency identification RFID reader-writer; acquiring second information of a second tag measured by the RFID reader-writer under a first preset condition; wherein the first preset condition is that liquid to be identified is arranged between the RFID reader-writer and the second tag; based on the first information and the second information, dielectric function information of the to-be-identified liquid is determined; and determining the liquid type of the to-be-identified liquid, wherein the liquid type of the to-be-identified liquid is a liquid type corresponding to the dielectric function information. According to the embodiment of the invention, the problem that the liquid identification effect is relatively poor due to the fact that the liquid identification effect is easily influenced by the liquid environment, the used identification equipment and the like can be solved.

Description

Technical Field

[0001] The present application relates to the technical field of material identification, and in particular to a liquid identification method, device, equipment, medium and program product based on RFID. Background Art

[0002] In liquid identification technology, most of them rely on the electrochemical and electrophysical properties of the measured liquid for identification. By placing the extracted liquid sample in a dedicated device, the properties of the liquid material, such as dielectric constant, surface tension, or optical characteristics, are obtained. In related technologies, liquid identification technology only uses the measured liquid property characteristics to identify the liquid type. The identification effect is easily affected by the environment in which the liquid is located, the identification equipment used, etc., resulting in poor liquid identification effect. Summary of the invention

[0003] In order to solve the problem that the liquid identification effect is easily affected by the liquid environment, the identification equipment used, etc., resulting in poor liquid identification effect, the embodiments of the present application provide an RFID-based liquid identification method, device, equipment, medium and program product, which can effectively improve the liquid identification effect.

[0004] In a first aspect, an embodiment of the present application provides a liquid identification method based on RFID, the method comprising:

[0005] Acquire first information of a first tag measured by a radio frequency identification (RFID) reader;

[0006] Acquire second information of the second tag measured by the RFID reader under a first preset condition; wherein the first preset condition is that a liquid to be identified is disposed between the RFID reader and the second tag;

[0007] Determining dielectric function information of the liquid to be identified based on the first information and the second information;

[0008] The liquid type of the liquid to be identified is determined, where the liquid type of the liquid to be identified is the liquid type corresponding to the dielectric function information.

[0009] Optionally, the obtaining of first information of a first tag measured by an RFID reader / writer includes:

[0010] Sending a first instruction to the RFID reader / writer, wherein the first instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the first tag;

[0011] Acquire a first reflection signal of the first tag received by the RFID reader;

[0012] The first information is determined based on the first reflected signal.

[0013] Optionally, the acquiring the second information of the second tag measured by the RFID reader under the first preset condition includes:

[0014] Sending a second instruction to the RFID reader / writer, wherein the second instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the second tag;

[0015] Acquire a second reflection signal received by the RFID reader / writer, where the second reflection signal is a signal reflected by the second tag and passing through the liquid to be identified;

[0016] The second information is determined based on the second reflected signal.

[0017] Optionally, the distance between the RFID reader and the first tag is equal to the distance between the RFID reader and the second tag, the first information includes a first received signal strength RSSI value and first phase information, and the second information includes a second RSSI value and second phase information;

[0018] The step of determining the dielectric function information of the liquid to be identified based on the first information and the second information includes:

[0019] Determining the dielectric constant of the liquid to be identified based on the first phase information and the second phase information;

[0020] Determine a liquid loss factor of the liquid to be identified based on a difference between the first RSSI value and the second RSSI value and a dielectric constant of the liquid to be identified;

[0021] The dielectric function information is determined based on the dielectric constant of the liquid to be identified and the liquid loss factor.

[0022] Optionally, determining the dielectric constant of the liquid to be identified based on the first phase information and the second phase information includes:

[0023] Determine the wavelength of the reflected signal of the second tag propagating in the liquid to be identified based on the wavelength of the reflected signal of the first tag or the second tag in the air, the distance between the RFID reader and the first tag, and the difference between the first phase information and the second phase information;

[0024] determining a refractive index of the liquid to be identified based on a wavelength of the reflection signal of the second tag propagating in the liquid to be identified and a frequency of the reflection signal of the second tag;

[0025] The dielectric constant of the liquid to be identified is determined based on the refractive index of the liquid to be identified and the difference between the first phase information and the second phase information.

[0026] Optionally, determining the liquid loss factor of the liquid to be identified based on the difference between the first RSSI value and the second RSSI value and the dielectric constant of the liquid to be identified includes:

[0027] Determine a second attenuation constant of the reflection signal of the second tag in the liquid to be identified based on a first attenuation constant of the reflection signal of the first tag or the second tag in the air and a difference between the first RSSI value and the second RSSI value;

[0028] Based on the second attenuation constant and the dielectric constant of the liquid to be identified, a liquid loss factor of the liquid to be identified is determined.

[0029] Optionally, determining the liquid type of the liquid to be identified includes:

[0030] Determining the liquid type of the liquid to be identified based on a pre-built dielectric function database;

[0031] The dielectric function database at least includes a target correspondence relationship, and the target correspondence relationship includes a correspondence relationship between a first liquid type and a dielectric function corresponding to a liquid of the first liquid type;

[0032] The target correspondence relationship is determined based on the following steps:

[0033] Acquire third information of the second tag measured by the RFID reader under a second preset condition; wherein the second preset condition is that liquid of the first liquid type is placed between the RFID reader and the second tag;

[0034] Determining a dielectric function corresponding to a liquid of the first liquid type based on the first information and the third information;

[0035] The dielectric function corresponding to the first liquid type and the liquid of the first liquid type is input into a preset model for training to obtain the target corresponding relationship.

[0036] In a second aspect, an embodiment of the present application provides a liquid identification device based on RFID, comprising:

[0037] A first acquisition module, used to acquire first information of a first tag measured by an RFID reader;

[0038] A second acquisition module is used to acquire second information of the second tag measured by the RFID reader under a first preset condition; wherein the first preset condition is that a liquid to be identified is set between the RFID reader and the second tag;

[0039] A first determination module, configured to determine the dielectric function information of the liquid to be identified based on the first information and the second information;

[0040] The second determination module is used to determine the liquid type of the liquid to be identified, where the liquid type of the liquid to be identified is the liquid type corresponding to the dielectric function information.

[0041] In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor, a memory, and a program stored in the memory and executable on the processor, wherein when the program is executed by the processor, the steps of the RFID-based liquid identification method as described in any one of the first aspects are implemented.

[0042] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the data packet retransmission method as described in any one of the first aspects are implemented.

[0043] In a fifth aspect, an embodiment of the present application further provides a computer program product, which is stored in a storage medium and is executed by at least one processor to implement the steps of the data packet retransmission method as described in any one of the first aspects.

[0044] In the embodiment of the present application, by acquiring the first information of the first tag measured by the radio frequency identification RFID reader, and the second information of the second tag measured when the liquid to be identified is set between the RFID reader and the second tag, the material characteristics of the liquid are extracted from the first information and the second information, thereby obtaining information that directly reflects the properties of the liquid, such as the dielectric function information of the liquid to be identified, and then determining the liquid type of the liquid to be identified based on the dielectric function information. In this way, by using the embodiment of the present application to identify the liquid type, the combination of the first information and the second information can accurately reflect the subtle differences between the liquids, and achieve a more fine-grained identification effect. Moreover, based on the maturity and low-cost characteristics of RDI technology, the embodiment of the present application lowers the threshold of liquid identification technology, and shows significant advantages in cost-effectiveness, ease of operation, and a wide range of application scenarios, effectively improving the liquid identification effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] 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 any creative labor.

[0046] Figure 1 is a flow chart of a liquid identification method based on RFID in an embodiment of the present application;

[0047] Figure 2 yes Figure 1 Schematic diagram of the implementation of the method;

[0048] Figure 3 yes Figure 1 Equipment deployment diagram for implementation of the method;

[0049] Figure 4 is a schematic diagram of a liquid identification device based on RFID in an embodiment of the present application;

[0050] Figure 5 It is a schematic diagram of an electronic device in an embodiment of the present application. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0052] In order to make the embodiments of the present application clearer, the relevant technical knowledge involved in the embodiments of the present application is first introduced as follows:

[0053] In the relevant technical field, liquid identification technology mostly relies on measuring electrochemical and electrophysical properties, extracting the properties of liquid materials, such as the dielectric constant, surface tension or optical characteristics of the liquid, by extracting samples and placing them in dedicated equipment. Usually, the following methods are included to distinguish or measure liquid categories:

[0054] The first liquid identification technology is to detect the type of liquid through Raman spectroscopy. Since different liquids will produce different scattering spectra when exposed to light of the same frequency, by analyzing the spectral characteristics, the relevant information of the liquid molecules can be inferred, thereby distinguishing different liquids and determining whether they are dangerous liquids. Raman spectroscopy is highly accurate in measuring liquid types and can detect a wide variety of substances.

[0055] The second liquid identification technology is to detect the type of liquid through X-rays. Since X-rays have very high penetrating power and can penetrate metals, they are often used in CT scanning and X-ray projection. By utilizing the strong penetrating power of X-rays to irradiate the liquid to be tested and analyzing the energy changes of the penetrating rays, the density and molecular information of the liquid can be obtained, and different liquids can be distinguished.

[0056] The third liquid identification technology is the technology of identifying liquids through wireless signals. When a wireless signal passes through a liquid, the liquid will affect the propagation characteristics of the wireless signal, including the signal propagation speed, signal strength attenuation, phase and received signal strength indicator (RSSI). At present, there are solutions using ultra-wideband (UWB) technology for liquid identification. Among them, UWB technology is a wireless communication technology with high bandwidth, low power, strong anti-interference, high resolution and good penetration ability. It can be applied to a variety of scenarios, including indoor positioning and navigation, high-speed data transmission, wireless sensor networks, inter-device communication, intelligent transportation systems, consumer electronics, medical equipment and security systems. In the liquid identification solution based on UWB technology, the phase change and time of flight (ToF) of the signal are jointly estimated to calculate the dielectric constant of the liquid. First, the UWB signal is sent to penetrate the liquid, and then the phase and ToF changes of the signal after penetration are received and analyzed. The changes are related to the physical properties of the liquid. The liquid is classified and identified according to the extracted key features to achieve fast and accurate detection of liquid properties.

[0057] However, the above liquid identification technology has the following technical defects:

[0058] (1) Although Raman spectroscopy is a highly specific and sensitive analytical method that is widely used in chemical analysis, pharmaceuticals and other fields, it has problems such as high cost, complex equipment, sample preparation requirements, high environmental interference, difficulty in data processing, long measurement time, non-portability, and sensitivity to pollution.

[0059] (2) X-ray detection technology is mainly used in liquid identification for security checks, such as airport baggage scanning, and industrial quality control to detect foreign matter or components inside liquids. However, X-ray detection technology requires the use of X-rays that are harmful to the human body and have radiation risks. In addition, the equipment is expensive, maintenance is complex, and in some cases, it has low environmental sensitivity, which limits its application scenarios.

[0060] (3) When using UWB technology for liquid identification, first of all, high time accuracy is required to ensure accurate time within a short distance. Clock synchronization and other operations are often required, otherwise the inaccurate estimation of liquid parameters will be affected due to insufficient time accuracy. Secondly, UWB equipment is expensive, and its wide frequency band can easily interfere with other wireless communication systems, so the application scenarios of UWB technology are limited.

[0061] Based on the above, the embodiments of the present application propose a liquid identification method, device, equipment, medium and program product based on RFID, which can extract the material characteristics of the liquid, such as dielectric constant and loss factor, from the radio frequency signal, so as to obtain parameters that directly reflect the properties of the liquid, so as to identify the type of liquid. This application combines RFID technology, based on the maturity and low-cost characteristics of RDI technology, lowers the threshold of liquid identification technology, and shows significant advantages in cost-effectiveness, ease of operation and wide application scenarios, thereby improving the identification effect.

[0062] In conjunction with the accompanying drawings, a RFID-based liquid identification method, device, equipment, medium and program product provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0063] See also Figure 1 , Figure 1 is a schematic diagram of a liquid identification method based on RFID provided in an embodiment of the present application, the method comprising the following steps:

[0064] Step 101: Acquire first information of a first tag measured by a radio frequency identification (RFID) reader / writer.

[0065] It should be noted that if Figure 2 As shown, after receiving the control instruction from the server, processor, data management / processing system, etc., the RFID reader can transmit a downlink excitation signal through the antenna, and the excitation signal is transmitted to the first tag. After receiving the excitation signal, the first tag reflects the data information to the RFID reader. Thus, the reflected data information directly reaches the RFID reader and is obtained as the first information by the server, management system, etc.

[0066] A container for the liquid to be identified can be set between the RFID reader and the first tag. The container is an empty container, and the container is the same as the container for the subsequent liquid to be identified. In this way, the measurement error can be reduced, the influence of other factors on liquid identification can be reduced, and the identification effect can be improved.

[0067] Step 102: Acquire second information of the second tag measured by the RFID reader under a first preset condition; wherein the first preset condition is that a liquid to be identified is disposed between the RFID reader and the second tag.

[0068] It is understandable that the first tag and the second tag can be the same tag, and the information content stored in the first tag and the second tag can be consistent. After the second tag receives the excitation signal sent by the RFID reader, the data information reflected by the second tag can be consistent with the data information reflected by the first tag. However, after the reflected data information of the second tag passes through the liquid to be identified, the second information received by the RFID reader is different from the first information.

[0069] In this step, when a liquid to be identified is placed between the RFID reader and the second tag, the second information of the second tag obtained is data information affected by the liquid to be identified. Figure 2 and Figure 3 As shown, the distances between the first tag and the second tag and the RFID reader are equal, an empty container may or may not be set between the first tag and the RFID reader, and a liquid to be identified may be set between the second tag and the RFID reader, and the liquid to be identified is placed in the same container placed between the first tag and the RFID reader. The distance between the first tag and the RFID reader is L, and the distance between the second tag and the RFID reader is also L.

[0070] Step 103: Determine the dielectric function information of the liquid to be identified based on the first information and the second information.

[0071] It is worth mentioning that the node function information can be the dielectric function of the liquid, and there is a close relationship between the dielectric function and the liquid type. The dielectric function is a physical quantity used to describe the electrical polarization properties of a substance in an electric field. Different types of liquids have different polarization responses to the electric field due to their different molecular structures, polarities, ion concentrations and other characteristics. Therefore, different liquids will have different dielectric functions. Based on this, the embodiment of the present application can determine the type of liquid to be identified by measuring the dielectric function information of the liquid.

[0072] Specifically, the first information can be used as a reference for the current environment, and the second information can be used as a reference for the impact of the liquid to be identified on the reflected signal. The first information and the second information can be preprocessed to obtain RSSI and phase information in the first information, as well as RSSI and phase information in the second information. Preprocessing can reduce the impact of equipment noise and environmental changes and improve liquid identification effects.

[0073] Furthermore, the material characteristics of the liquid to be identified can be extracted through multiple models of electromagnetic fields and materials science, through the RSSI and phase information in the first information, and the RSSI and phase information in the second information. First, the dielectric constant characteristics of the liquid to be identified can be extracted. The phase display of the radio frequency signal is different in different cases where the container contains liquid and does not contain liquid, mainly because the liquid to be identified affects the propagation of the radio frequency signal. Therefore, the polarization properties of the liquid to be identified can be obtained by combining analysis from the perspectives of materials science and electromagnetic fields. Secondly, the RSSI of the radio frequency signal is also different in different cases where the container contains liquid and does not contain liquid, mainly because the radio frequency signal dissipates energy when passing through the liquid to be identified. Therefore, the RSSI can be analyzed to determine the attenuation of the radio frequency signal in the liquid to be identified, and obtain the attenuation factor of the liquid. Combining the obtained polarization properties and attenuation factors, the dielectric function information of the liquid to be identified can be obtained.

[0074] It can be seen that the embodiments of the present application can accurately reflect the subtle differences between liquids only through the first information and the second information, and achieve a finer-grained recognition effect. At the same time, there is no need to calculate the propagation time of the radio frequency signal, that is, there is no need to consider the problem of clock synchronization. The hardware requirements and clock requirements for the tested tag and RFID reader are relatively low, which simplifies the recognition process, reduces the measurement cost, and improves the liquid recognition effect.

[0075] Step 104: Determine the liquid type of the liquid to be identified, where the liquid type of the liquid to be identified is the liquid type corresponding to the dielectric function information.

[0076] In a specific embodiment of the present application, different dielectric function information corresponds to the physical and chemical properties of different liquids, and the dielectric function information of each liquid can be pre-stored in a dielectric function database. After determining the dielectric function information of the liquid to be identified, the specific type of the liquid to be identified can be determined by directly comparing the dielectric function information in the dielectric function database. In this way, based on the maturity and low-cost characteristics of RFID technology, the embodiment of the present application obtains the first information and the second information, and determines the dielectric function information of the liquid to be identified by combining the first information and the second information, so as to determine the specific type of the liquid to be identified according to the dielectric function information, which lowers the threshold of liquid identification technology, shows significant advantages in cost-effectiveness, ease of operation, and a wide range of application scenarios, and effectively improves the liquid identification effect.

[0077] Optionally, the obtaining of first information of a first tag measured by an RFID reader / writer includes:

[0078] Sending a first instruction to the RFID reader / writer, wherein the first instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the first tag;

[0079] Acquire a first reflection signal of the first tag received by the RFID reader;

[0080] The first information is determined based on the first reflected signal.

[0081] See also Figure 3 , Figure 3 This is a diagram of the equipment deployment for the implementation of the RFID-based liquid identification method in this application, where point O is the location of the RFID reader, the first tag and the second tag can be the same type of tag, respectively placed on both sides of the RFID reader, and the distance from the RFID reader is the same, both L. The container for the liquid to be identified and the empty container are the same type of container, both have a width of D, and the container is placed between the first tag and the RFID reader, and between the second tag and the RFID reader.

[0082] In a specific implementation, the RFID reader receives a first instruction, and the first instruction instructs to transmit an excitation signal to the first tag. Then, the antenna of the RFID reader can be rotated to a direction parallel to the first tag, and the excitation signal is sent to the first tag. When there is no liquid, when the first tag and the RFID reader are at a distance of L, the RSSI value and phase information in the first information received by the RFID reader are respectively recorded as RSSI A and in, Affected by the propagation in the first tag, RFID reader and air, it can be expressed as:

[0083]

[0084] in, represents the additional phase shift introduced by the first tag; represents the additional phase shift introduced by the RFID reader; Represents the phase shift caused by propagation in air.

[0085] Optionally, the acquiring the second information of the second tag measured by the RFID reader under the first preset condition includes:

[0086] Sending a second instruction to the RFID reader / writer, wherein the second instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the second tag;

[0087] Acquire a second reflection signal received by the RFID reader / writer, where the second reflection signal is a signal reflected by the second tag and passing through the liquid to be identified;

[0088] The second information is determined based on the second reflected signal.

[0089] Please continue to refer to Figure 3When the liquid to be identified is placed in the container, the second information can be obtained through the RFID reader. The antenna of the RFID reader can be rotated to be parallel to the second tag, and an excitation signal is sent to the second tag to obtain the RSSI value and phase information in the second information when the distance between the second tag and the RFID reader is L when the liquid to be identified is placed in the container, which are recorded as RSSI B and Affected by the second tag, RFID reader, propagation in the air, and propagation in the liquid to be identified, it can be expressed as:

[0090]

[0091] in, represents the phase shift caused by propagation in air; represents the phase shift caused by propagation in the liquid to be identified.

[0092] It can be understood that in the embodiment of the present application, the same RFID reader is used to obtain the first information and the second information, and the first tag and the second tag used are the same tag or the same type of tags. Therefore, the obtained phase difference eliminates the phase shift caused by equipment such as tags and RFID readers, and also reduces the impact of the environment, making the measurement results more stable and reliable, and enhancing robustness.

[0093] Optionally, the distance between the RFID reader and the first tag is equal to the distance between the RFID reader and the second tag, the first information includes a first received signal strength RSSI value and first phase information, and the second information includes a second RSSI value and second phase information;

[0094] The step of determining the dielectric function information of the liquid to be identified based on the first information and the second information includes:

[0095] Determining the dielectric constant of the liquid to be identified based on the first phase information and the second phase information;

[0096] Determine a liquid loss factor of the liquid to be identified based on a difference between the first RSSI value and the second RSSI value and a dielectric constant of the liquid to be identified;

[0097] The dielectric function information is determined based on the dielectric constant of the liquid to be identified and the liquid loss factor.

[0098] It should be noted that the first information includes the first RSSI value and the first phase information, which are correspondingly recorded as RSSI A and The second information includes a second RSSI value and a second phase information, which is correspondingly recorded as RSSI B and

[0099] In some embodiments, the first phase information and the second phase information are analyzed and processed to obtain the dielectric constant of the liquid to be identified:

[0100]

[0101] Among them, ε′ is the dielectric constant corresponding to the liquid to be identified; ε0 is the dielectric constant in vacuum; D is the width of the container containing the liquid to be identified; is the difference between the first phase information and the second phase information; λ air represents the wavelength of the RF signal in the air; c represents the speed of light; and f represents the frequency of the RF signal.

[0102] By analyzing and processing the first RSSI value and the second RSSI value, the loss factor of the liquid to be identified can be obtained as follows:

[0103]

[0104] Where ε″ represents the loss factor of the liquid to be identified; α air represents the first attenuation constant of the reflected signal in the air, which is a constant; ΔR represents the difference between the first RSSI value and the second RSSI value.

[0105] Therefore, according to the dielectric constant and loss factor of the liquid to be identified, the dielectric function information of the liquid to be identified can be determined as: ε=ε′-jε″, wherein j is a constant determined according to the dielectric constant and loss factor.

[0106] In this way, the present application considers the loss factor and frequency dependence of the liquid to be identified, and by determining the dielectric function information of the liquid to be identified, the dielectric function information can more accurately reflect the characteristics of the liquid to be identified, compared with single parameters such as dielectric constant and loss factor, so as to make the measurement results more stable and reliable, so as to achieve a more fine-grained liquid identification effect. In addition, the embodiment of the present application only needs to collect a small amount of the first information and the second information to accurately identify the liquid to be identified, which lowers the application threshold of liquid identification and reduces the identification cost.

[0107] Optionally, determining the dielectric constant of the liquid to be identified based on the first phase information and the second phase information includes:

[0108] Determine the wavelength of the reflection signal of the second tag propagating in the liquid to be identified based on the wavelength of the reflection signal of the first tag or the second tag in the air, the distance between the RFID reader and the first tag, and the difference between the first phase information and the second phase information;

[0109] determining a refractive index of the liquid to be identified based on a wavelength of the reflection signal of the second tag propagating in the liquid to be identified and a frequency of the reflection signal of the second tag;

[0110] The dielectric constant of the liquid to be identified is determined based on the refractive index of the liquid to be identified and the difference between the first phase information and the second phase information.

[0111] In some specific embodiments, the first phase information and the second phase information The difference can be expressed as:

[0112]

[0113] Among them, λ air Represents the wavelength of the RF signal in the air; λ liquid Represents the wavelength of the RF signal in the liquid.

[0114] In the above formula, due to λ air and D are known, so λ can be converted to liquid Solve it and get v = λ liquid f, v represents the propagation speed of the RF signal, and f represents the frequency of the RF signal. And c represents the speed of light, and n represents the refractive index of the liquid to be identified. Thus, we can get:

[0115]

[0116] Among them, due to the formula f, c, λ liquid If all are known parameters, then n can be calculated and the refractive index of the liquid to be identified can be obtained.

[0117] Furthermore, according to the relationship between the refractive index and the dielectric constant of the liquid to be identified, the following formula can be obtained:

[0118]

[0119] Among them, ε′ is the dielectric constant corresponding to the liquid to be identified; ε0 is the dielectric constant in vacuum.

[0120] Therefore, we can combine v = λ liquid f' and The dielectric constant of the liquid to be identified is: The λ obtained above liquid Substituting this into the equation, we get:

[0121]

[0122] In this way, through the above processing, the dielectric constant of the liquid to be identified can be obtained. This process eliminates the phase shift caused by devices such as the first tag, the second tag and the RFID reader, and also reduces the impact of the environment on the liquid identification effect, making the measurement results more stable and reliable, so as to achieve a more fine-grained liquid identification effect.

[0123] Optionally, determining the liquid loss factor of the liquid to be identified based on the difference between the first RSSI value and the second RSSI value and the dielectric constant of the liquid to be identified includes:

[0124] Determine a second attenuation constant of the reflection signal of the second tag in the liquid to be identified based on a first attenuation constant of the reflection signal of the first tag or the second tag in the air and a difference between the first RSSI value and the second RSSI value;

[0125] Based on the second attenuation constant and the dielectric constant of the liquid to be identified, a liquid loss factor of the liquid to be identified is determined.

[0126] In some further specific embodiments, the difference between the first RSSI value and the second RSSI value may be expressed as:

[0127]

[0128] Among them, A A a signal amplitude representing a reflection signal of the first tag;

[0129] A B a signal amplitude representing a reflected signal of the second tag;

[0130] A S Indicates the signal amplitude of the transmission signal of the RFID reader;

[0131] α air Represents the first attenuation constant of the reflected signal in the air, which is a constant;

[0132] α liquid Represents the second attenuation constant of the reflected signal in the liquid to be identified.

[0133] Since the difference between the first RSSI value and the second RSSI value is a known number, A A , A B , A S and α air If we know the second attenuation constant α, we can get liquid .

[0134] Then, substituting the second decay constant into the formula In combination with the loss factor formula The loss factor of the liquid to be identified can be obtained as:

[0135]

[0136] Wherein, α represents the attenuation constant, σ represents the magnetic permeability of the liquid to be identified, and ε″ represents the loss factor of the liquid to be identified.

[0137] Optionally, determining the liquid type of the liquid to be identified includes:

[0138] Determining the liquid type of the liquid to be identified based on a pre-built dielectric function database;

[0139] The dielectric function database at least includes a target correspondence relationship, and the target correspondence relationship includes a correspondence relationship between a first liquid type and a dielectric function corresponding to a liquid of the first liquid type;

[0140] The target correspondence relationship is determined based on the following steps:

[0141] Acquire third information of the second tag measured by the RFID reader under a second preset condition; wherein the second preset condition is that liquid of the first liquid type is placed between the RFID reader and the second tag;

[0142] Determining a dielectric function corresponding to a liquid of the first liquid type based on the first information and the third information;

[0143] The dielectric function corresponding to the first liquid type and the liquid of the first liquid type is input into a preset model for training to obtain the target corresponding relationship.

[0144] In some specific embodiments of the present application, based on a pre-constructed dielectric function database, the dielectric function information in the target correspondence included in the dielectric function database can be found, and the liquid type corresponding to the dielectric function information in the target correspondence is determined to be the liquid type of the liquid to be identified. The target correspondence may be pre-stored in the dielectric function database.

[0145] Specifically, a small amount of liquid data (including first information and second information) of a certain type of liquid is collected to determine the dielectric function information corresponding to the type of liquid. Subsequently, machine learning is used for training, and the dielectric function information of the type of liquid and the type of liquid (i.e., the target correspondence) are input into the dielectric function input preset model to obtain a more fine-grained model and establish a self-built database.

[0146] In addition, the dielectric function database in the embodiment of the present application may also be a traditional database such as PubChem, MaterialsProject and Springer Materials, and the present application does not impose specific restrictions on this. When the liquid type to be identified is to be identified, first determine whether the dielectric function information of the liquid to be identified is in the dielectric function database. If so, determine the target correspondence of the dielectric function information in the dielectric function database, return the liquid type displayed in the target correspondence, and save the data for training. When the liquid to be identified is not in the previously trained dielectric function database, the preset model according to the dielectric function input is compared and verified with the dielectric function database to identify and determine the liquid type, obtain the liquid type of the liquid to be identified, and save the target correspondence of the liquid to be identified in the dielectric function database.

[0147] For example, in the related technical field, it is necessary to collect 80 sets of data for one liquid. If you want to recognize 10 liquids, you need to collect 800 sets of data to complete the machine learning training. And if you need to increase the types of identifiable liquids in the later stage, you need to re-collect the information of the liquid to be recognized for data training. In the embodiment of the present application, only a small amount of liquids of various types need to be collected and trained in the early stage, and all liquids can be recognized.

[0148] In this way, the embodiment of the present application can also collect a small amount of liquid data and use machine learning methods to train the dielectric function input preset model so that the dielectric function input preset model data can correspond to the dielectric function database. It can be seen that the embodiment of the present application has fewer restrictions on liquid identification conditions and can be widely used in various scenarios and environments. The identification threshold and cost are low and the identification effect is good.

[0149] See also Figure 4 The embodiment of the present application provides a liquid identification device 200 based on RFID, the device comprising:

[0150] A first acquisition module 201 is used to acquire first information of a first tag measured by an RFID reader;

[0151] A second acquisition module 202 is used to acquire second information of a second tag measured by the RFID reader under a first preset condition; wherein the first preset condition is that a liquid to be identified is disposed between the RFID reader and the second tag;

[0152] A first determination module 203, configured to determine the dielectric function information of the liquid to be identified based on the first information and the second information;

[0153] The second determination module 204 is used to determine the liquid type of the liquid to be identified, where the liquid type of the liquid to be identified is the liquid type corresponding to the dielectric function information.

[0154] Optionally, the first acquisition module 201 includes:

[0155] A first sending unit, configured to send a first instruction to the RFID reader / writer, wherein the first instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the first tag;

[0156] A first acquisition unit, configured to acquire a first reflection signal of the first tag received by the RFID reader;

[0157] The first determining unit is configured to determine the first information based on the first reflected signal.

[0158] Optionally, the second acquisition module 202 includes:

[0159] A second sending unit, used for sending a second instruction to the RFID reader / writer, wherein the second instruction is used for instructing the RFID reader / writer to transmit an excitation signal to the second tag;

[0160] A second acquisition unit is used to acquire a second reflection signal received by the RFID reader / writer, where the second reflection signal is a signal reflected by the second tag and passing through the liquid to be identified;

[0161] The second determining unit is configured to determine the second information based on the second reflected signal.

[0162] Optionally, the distance between the RFID reader and the first tag is equal to the distance between the RFID reader and the second tag, the first information includes a first received signal strength RSSI value and first phase information, and the second information includes a second RSSI value and second phase information;

[0163] The first determining module 203 includes:

[0164] a third determining unit, configured to determine a dielectric constant of the liquid to be identified based on the first phase information and the second phase information;

[0165] a fourth determining unit, configured to determine a liquid loss factor of the liquid to be identified based on a difference between the first RSSI value and the second RSSI value and a dielectric constant of the liquid to be identified;

[0166] A fifth determining unit is used to determine the dielectric function information based on the dielectric constant of the liquid to be identified and the liquid loss factor.

[0167] Optionally, the first determining module 203 includes:

[0168] a sixth determining unit, configured to determine the wavelength of the reflection signal of the second tag propagating in the liquid to be identified based on the wavelength of the reflection signal of the first tag or the second tag in the air, the distance between the RFID reader and the first tag, and the difference between the first phase information and the second phase information;

[0169] a seventh determining unit, configured to determine a refractive index of the liquid to be identified based on a wavelength of the reflection signal of the second tag propagating in the liquid to be identified and a frequency of the reflection signal of the second tag;

[0170] An eighth determination unit is used to determine the dielectric constant of the liquid to be identified based on the refractive index of the liquid to be identified and the difference between the first phase information and the second phase information.

[0171] Optionally, the fourth determining unit is used to:

[0172] Determine a second attenuation constant of the reflection signal of the second tag in the liquid to be identified based on a first attenuation constant of the reflection signal of the first tag or the second tag in the air and a difference between the first RSSI value and the second RSSI value;

[0173] Based on the second attenuation constant and the dielectric constant of the liquid to be identified, a liquid loss factor of the liquid to be identified is determined.

[0174] Optionally, the second determining module 204 includes:

[0175] a ninth determination unit, configured to determine the liquid type of the liquid to be identified based on a pre-built dielectric function database;

[0176] The dielectric function database at least includes a target correspondence relationship, and the target correspondence relationship includes a correspondence relationship between a first liquid type and a dielectric function corresponding to a liquid of the first liquid type;

[0177] The target correspondence relationship is determined based on the following steps:

[0178] Acquire third information of the second tag measured by the RFID reader under a second preset condition; wherein the second preset condition is that liquid of the first liquid type is placed between the RFID reader and the second tag;

[0179] Determining a dielectric function corresponding to a liquid of the first liquid type based on the first information and the third information;

[0180] The dielectric function corresponding to the first liquid type and the liquid of the first liquid type is input into a preset model for training to obtain the target corresponding relationship.

[0181] It should be noted that the RFID-based liquid identification device provided in the embodiment of the present application can achieve the above Figure 1 All the method steps implemented in the method embodiment shown can achieve the same technical effect, and the parts and beneficial effects of this embodiment that are the same as those in the method embodiment will not be described in detail here.

[0182] See also Figure 5 , Figure 5 is a structural diagram of an electronic device provided in an embodiment of the present application. Since the principle of solving the problem by the electronic device is similar to the liquid identification method based on RFID in the embodiment of the present application, the implementation of the electronic device can refer to Figure 1 The implementation of the method shown will not be repeated in detail.

[0183] like Figure 5 As shown, the electronic device includes: a processor 300, which is used to read the program in the memory 320 and execute the following process:

[0184] Acquire first information of a first tag measured by a radio frequency identification (RFID) reader;

[0185] Acquire second information of the second tag measured by the RFID reader under a first preset condition; wherein the first preset condition is that a liquid to be identified is disposed between the RFID reader and the second tag;

[0186] Determining dielectric function information of the liquid to be identified based on the first information and the second information;

[0187] The liquid type of the liquid to be identified is determined, where the liquid type of the liquid to be identified is the liquid type corresponding to the dielectric function information.

[0188] The transceiver 310 is configured to receive and send data under the control of the processor 300 .

[0189] Among them, Figure 5 In the embodiment of the present invention, the bus architecture may include any number of interconnected buses and bridges, specifically linking together various circuits of one or more processors represented by processor 300 and memory represented by memory 320. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface.

[0190] Optionally, the processor 300 is further configured to read a program in the memory 320 and execute the following steps:

[0191] Sending a first instruction to the RFID reader / writer through the transceiver 310, wherein the first instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the first tag;

[0192] Acquire a first reflection signal of the first tag received by the RFID reader;

[0193] The first information is determined based on the first reflected signal.

[0194] Optionally, the processor 300 is further configured to read a program in the memory 320 and execute the following steps:

[0195] Sending a second instruction to the RFID reader / writer through the transceiver 310, wherein the second instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the second tag;

[0196] Acquire a second reflection signal received by the RFID reader / writer, where the second reflection signal is a signal reflected by the second tag and passing through the liquid to be identified;

[0197] The second information is determined based on the second reflected signal.

[0198] Optionally, the distance between the RFID reader and the first tag is equal to the distance between the RFID reader and the second tag, the first information includes a first received signal strength RSSI value and first phase information, and the second information includes a second RSSI value and second phase information;

[0199] The processor 300 is further configured to read the program in the memory 320 and execute the following steps:

[0200] Determining the dielectric constant of the liquid to be identified based on the first phase information and the second phase information;

[0201] Determine a liquid loss factor of the liquid to be identified based on a difference between the first RSSI value and the second RSSI value and a dielectric constant of the liquid to be identified;

[0202] The dielectric function information is determined based on the dielectric constant of the liquid to be identified and the liquid loss factor.

[0203] Optionally, the processor 300 is further configured to read a program in the memory 320 and execute the following steps:

[0204] Determine the wavelength of the reflected signal of the second tag propagating in the liquid to be identified based on the wavelength of the reflected signal of the first tag or the second tag in the air, the distance between the RFID reader and the first tag, and the difference between the first phase information and the second phase information;

[0205] determining a refractive index of the liquid to be identified based on a wavelength of the reflection signal of the second tag propagating in the liquid to be identified and a frequency of the reflection signal of the second tag;

[0206] The dielectric constant of the liquid to be identified is determined based on the refractive index of the liquid to be identified and the difference between the first phase information and the second phase information.

[0207] Optionally, the processor 300 is further configured to read a program in the memory 320 and execute the following steps:

[0208] Determine a second attenuation constant of the reflection signal of the second tag in the liquid to be identified based on a first attenuation constant of the reflection signal of the first tag or the second tag in the air and a difference between the first RSSI value and the second RSSI value;

[0209] Based on the second attenuation constant and the dielectric constant of the liquid to be identified, a liquid loss factor of the liquid to be identified is determined.

[0210] Optionally, the processor 300 is further configured to read a program in the memory 320 and execute the following steps:

[0211] Determining the liquid type of the liquid to be identified based on a pre-built dielectric function database;

[0212] The dielectric function database at least includes a target correspondence relationship, and the target correspondence relationship includes a correspondence relationship between a first liquid type and a dielectric function corresponding to a liquid of the first liquid type;

[0213] The target correspondence relationship is determined based on the following steps:

[0214] Acquire third information of the second tag measured by the RFID reader under a second preset condition; wherein the second preset condition is that liquid of the first liquid type is placed between the RFID reader and the second tag;

[0215] Determining a dielectric function corresponding to a liquid of the first liquid type based on the first information and the third information;

[0216] The dielectric function corresponding to the first liquid type and the liquid of the first liquid type is input into a preset model for training to obtain the target corresponding relationship.

[0217] The electronic device provided in the embodiment of the present application can perform the above Figure 1 The implementation principle and technical effect of the method embodiment shown are similar, and this embodiment will not be repeated here.

[0218] The present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned Figure 1 The various processes of the embodiment of the liquid identification method based on RFID can achieve the same technical effect, and are not described here to avoid repetition. The computer-readable storage medium is, for example, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0219] The present application embodiment further provides a computer program / program product, wherein the computer program / program product is stored in a storage medium, and the computer program / program product is executed by at least one processor to implement the above Figure 1 The various processes of the RFID-based liquid identification method embodiment can achieve the same technical effect, and will not be described here to avoid repetition.

[0220] In the several embodiments provided in the present application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0221] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may be physically included separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0222] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform some steps of the sending and receiving method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (RandomAccess Memory, RAM), disk or optical disk and other media that can store program codes.

[0223] The above is a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles described in the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A liquid identification method based on RFID, characterized in that: include: Acquire first information of a first tag measured by a radio frequency identification (RFID) reader; Acquire second information of the second tag measured by the RFID reader under a first preset condition; wherein the first preset condition is that a liquid to be identified is disposed between the RFID reader and the second tag; Determining dielectric function information of the liquid to be identified based on the first information and the second information; The liquid type of the liquid to be identified is determined, where the liquid type of the liquid to be identified is the liquid type corresponding to the dielectric function information.

2. The method according to claim 1, characterized in that The obtaining of first information of a first tag measured by an RFID reader / writer includes: Sending a first instruction to the RFID reader / writer, wherein the first instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the first tag; Acquire a first reflection signal of the first tag received by the RFID reader; The first information is determined based on the first reflected signal.

3. The method according to claim 1, characterized in that The obtaining the second information of the second tag measured by the RFID reader under the first preset condition includes: Sending a second instruction to the RFID reader / writer, wherein the second instruction is used to instruct the RFID reader / writer to transmit an excitation signal to the second tag; Acquire a second reflection signal received by the RFID reader / writer, where the second reflection signal is a signal reflected by the second tag and passing through the liquid to be identified; The second information is determined based on the second reflected signal.

4. The method according to claim 1, characterized in that: The distance between the RFID reader and the first tag is equal to the distance between the RFID reader and the second tag, the first information includes a first received signal strength RSSI value and first phase information, and the second information includes a second RSSI value and second phase information; The step of determining the dielectric function information of the liquid to be identified based on the first information and the second information includes: Determining the dielectric constant of the liquid to be identified based on the first phase information and the second phase information; Determine a liquid loss factor of the liquid to be identified based on a difference between the first RSSI value and the second RSSI value and a dielectric constant of the liquid to be identified; The dielectric function information is determined based on the dielectric constant of the liquid to be identified and the liquid loss factor.

5. The method according to claim 4, characterized in that The step of determining the dielectric constant of the liquid to be identified based on the first phase information and the second phase information includes: Determine the wavelength of the reflected signal of the second tag propagating in the liquid to be identified based on the wavelength of the reflected signal of the first tag or the second tag in the air, the distance between the RFID reader and the first tag, and the difference between the first phase information and the second phase information; determining a refractive index of the liquid to be identified based on a wavelength of the reflection signal of the second tag propagating in the liquid to be identified and a frequency of the reflection signal of the second tag; The dielectric constant of the liquid to be identified is determined based on the refractive index of the liquid to be identified and the difference between the first phase information and the second phase information.

6. The method according to claim 4, characterized in that The determining the liquid loss factor of the liquid to be identified based on the difference between the first RSSI value and the second RSSI value and the dielectric constant of the liquid to be identified includes: Determine a second attenuation constant of the reflection signal of the second tag in the liquid to be identified based on a first attenuation constant of the reflection signal of the first tag or the second tag in the air and a difference between the first RSSI value and the second RSSI value; Based on the second attenuation constant and the dielectric constant of the liquid to be identified, a liquid loss factor of the liquid to be identified is determined.

7. The method according to any one of claims 1 to 6, characterized in that The step of determining the liquid type of the liquid to be identified comprises: Determining the liquid type of the liquid to be identified based on a pre-built dielectric function database; The dielectric function database at least includes a target correspondence relationship, and the target correspondence relationship includes a correspondence relationship between a first liquid type and a dielectric function corresponding to a liquid of the first liquid type; The target correspondence relationship is determined based on the following steps: Acquire third information of the second tag measured by the RFID reader under a second preset condition; wherein the second preset condition is that liquid of the first liquid type is placed between the RFID reader and the second tag; Determining a dielectric function corresponding to a liquid of the first liquid type based on the first information and the third information; The dielectric function corresponding to the first liquid type and the liquid of the first liquid type is input into a preset model for training to obtain the target corresponding relationship.

8. A liquid identification device based on RFID, characterized in that: include: A first acquisition module, used to acquire first information of a first tag measured by an RFID reader; A second acquisition module is used to acquire second information of the second tag measured by the RFID reader under a first preset condition; wherein the first preset condition is that a liquid to be identified is set between the RFID reader and the second tag; A first determination module, configured to determine the dielectric function information of the liquid to be identified based on the first information and the second information; The second determination module is used to determine the liquid type of the liquid to be identified, where the liquid type of the liquid to be identified is the liquid type corresponding to the dielectric function information.

9. An electronic device, characterized in that: include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein when the program is executed by the processor, the steps of the RFID-based liquid identification method as claimed in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium for storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the RFID-based liquid identification method according to any one of claims 1 to 7 are implemented.

11. A computer program product, characterized in that The method comprises computer instructions, which, when executed by a processor, implement the steps in the RFID-based liquid identification method as claimed in any one of claims 1 to 7.

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