A data sensing method and data sensing circuit based on radio frequency identification chip

Abstract

The present invention discloses a data sensing method and a data sensing circuit based on a radio frequency identification chip, and relates to the field of radio frequency identification technology. The method includes: sending a radio frequency signal to the radio frequency identification chips of multiple sensing objects in a field area to start sensing by powering on; sending a data reading instruction carrying the ID information of the sensing object to the radio frequency identification chip through a reader / writer; when the radio frequency identification chip corresponding to the ID information in the field area receives the data reading instruction, the sensor in the radio frequency identification chip obtains the detection data of the sensing object corresponding to the ID information, and transmits the detection data back to the reader / writer. The present application directly sends a data reading instruction carrying the ID information of the sensing object to the radio frequency identification chip in the field area, reads the detection data of the sensing object corresponding to the ID information in the field area and transmits it back to the reader / writer, which saves the cumbersome inventory process compared to traditional sensing, can reduce the time to complete a single sensing, and speed up the sensing speed.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency identification technology, and in particular to a data sensing method and a data sensing circuit based on a radio frequency identification chip. Background Art

[0002] Radio Frequency Identification (RFID) is widely used in warehouse logistics, anti-counterfeiting and traceability, anti-channeling, asset management, access control, train / car identification / baggage security, medical information tracking and other fields. In high-speed mobile applications, the tag moves fast and stays in the antenna coverage area for a short time, so a faster sensing speed is required. In the traditional sensing method, the tag that matches the target according to the inventory instruction is first counted (0 to 2 seconds). Q-1 ) and loads the random number into its slot counter. The tag that responds to the Query command loads its slot counter with zero, and the tag responds to the Query command; if the tag's random number is not 0, the Query_adj / query_rep instructions are used to adjust the Q value of the target tag to 0, and then communication with the target tag is achieved. It can be seen that this process requires verification of the random number, which will prolong the sensing time of a single sensing and slow the sensing speed. Summary of the invention

[0003] The purpose of the present invention is to address the problems that the sensing process of the traditional sensing method needs to verify the random number, prolong the sensing time of a single sensing, and has a slow sensing speed. A data sensing method and a data sensing circuit based on a radio frequency identification chip are proposed. After the radio frequency identification chip of the sensing object in the field is powered on, a data reading instruction carrying the ID information of the sensing object is directly sent to the radio frequency identification chip in the field. The detection data of the sensing object corresponding to the ID information in the field is read and transmitted back to the reader / writer. Compared with the traditional sensing, the cumbersome inventory process is omitted, the time to complete a single sensing can be reduced, and the sensing speed can be accelerated.

[0004] In a first aspect, a technical solution provided in an embodiment of the present invention is a data sensing method based on a radio frequency identification chip, comprising the following steps:

[0005] Sending radio frequency signals to the radio frequency identification chips of multiple sensing objects in the field area to power on and start sensing;

[0006] Sending a data reading instruction to the RFID chip through a reader / writer, wherein the data reading instruction carries the ID information of the sensing object;

[0007] When the RFID chip corresponding to the ID information carried by the data reading command in the field receives the data reading instruction, the sensor in the RFID chip obtains the detection data of the sensing object corresponding to the ID information, and transmits the detection data back to the reader / writer.

[0008] Furthermore, the sending of radio frequency signals to radio frequency identification chips of multiple sensing objects in the field area to power on and start sensing includes:

[0009] The reader sends the radio frequency signal through a first antenna on the reader side;

[0010] If the second antenna on the RFID chip side in the field area receives the RFID signal, the RFID signal is demodulated by a demodulator, and the demodulated signal obtained after demodulation is used to input the start-up energy to the RFID chip, and then the sensor is powered on, wherein the field area includes at least one RFID chip;

[0011] If a plurality of the RFID chips in the field receive activation energy that meets the activation condition, each of the RFID chips that meets the activation condition starts sensing.

[0012] Furthermore, the data reading instruction includes an ACK instruction, and the acquiring of detection data of the sensing object corresponding to the ID information through the sensor in the RFID chip and the transmission of the detection data back to the reader / writer includes: performing object matching in the field area according to the ID information of the sensing object carried in the ACK instruction, and determining the RFID chip corresponding to the ID information among the plurality of RFID chips that have started sensing;

[0013] The detection data of the sensing object corresponding to the ID information is obtained through the sensor in the RFID chip corresponding to the ID information, and stored in the memory EPC area in the RFID chip. The detection data is read from the memory EPC area through the ACK instruction, and the detection data is transmitted back to the reader / writer.

[0014] Furthermore, after transmitting the detection data back to the reader / writer, the method further includes:

[0015] When the ACK instruction includes the ID information of multiple sensing objects and the detection data of multiple sensing objects are obtained, a detection data sequence is constructed for the multiple detection data obtained according to the acquisition time in the reader;

[0016] The detection data sequence is uploaded to the requesting terminal through the reader / writer.

[0017] Furthermore, after determining the detection data sequence based on the acquisition time of the plurality of detection data in the reader / writer, the method further comprises:

[0018] Determine in the reader whether all detection data corresponding to the ID information in the ACK instruction is obtained;

[0019] If there is any unobtained detection data, an alarm message is generated and fed back to the request terminal, and a repeated ACK instruction is sent to the RFID chip in the field at least once, wherein the repeated ACK instruction includes the ID information of the unobtained sensing object;

[0020] When the number of times the instruction is repeatedly sent reaches a predetermined threshold, the acquisition is terminated, and the final acquisition result is transmitted back to the requesting terminal through the reader / writer.

[0021] Furthermore, after the second antenna on the RFID chip side in the field area receives the RF signal, the method further includes: rectifying the RF signal by a rectifier in the RFID chip.

[0022] In the second aspect, a technical solution provided in an embodiment of the present invention is a data sensing circuit based on a radio frequency identification chip, comprising a main control module, a signal receiving module and a data sensing module, wherein the signal receiving module and the data sensing module are connected to the main control module, and the circuit also comprises: a sensor start control module, a dummy load module and an impedance matching adjustment module, wherein the sensor start control module and the dummy load module are respectively connected to the main control module, the impedance matching adjustment module is connected to the signal receiving module, and the dummy load module is also connected to the data sensing module.

[0023] Furthermore, the sensor start control module includes a TRIM controller and a controller switch with two ends respectively connected to the TRIM controller, the TRIM controller is connected to the main control module, and after the controller switch is closed, the TRIM controller outputs a sensor start signal to the main control module.

[0024] Furthermore, the dummy load module includes a dummy load sensor, a first load control switch, a second load control switch and a first resistor;

[0025] The first end of the dummy load sensor is connected to one end of the second load control switch, the second end is connected to one end of the first load control switch, the third end is connected to one end of the data sensing module, and the fourth end is grounded;

[0026] The second load control switch is connected in series with the first resistor, and the other end of the first resistor, the other end of the first load control switch and the other end of the data sensing module are connected.

[0027] Furthermore, the circuit also includes a storage module, the storage module is connected to the main control module, and the storage module includes a memory and a clock circuit connected to the memory.

[0028] Beneficial effects of the invention: The invention proposes a data sensing method based on a radio frequency identification chip. After the radio frequency identification chip of the sensing object in the field is powered on, a data reading instruction carrying the ID information of the sensing object is directly sent to the radio frequency identification chip in the field. The detection data of the sensing object corresponding to the ID information in the field is read and transmitted back to the reader / writer. Compared with traditional sensing, the cumbersome inventory process is omitted, the process of random number verification before communication sensing is avoided, the time to complete a single sensing is reduced, and the sensing speed is accelerated.

[0029] The above invention content is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings. The drawings are only for the purpose of illustrating preferred embodiments and are not to be considered as limiting the present invention. Also, the same reference symbols are used throughout the drawings to represent the same parts.

[0031] Figure 1 A flow chart of a data sensing method based on a radio frequency identification chip provided by an embodiment of the present invention;

[0032] Figure 2 A schematic diagram of a sensing process of a data sensing method based on a radio frequency identification chip provided by an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of a module of a data sensing circuit based on a radio frequency identification chip provided by an embodiment of the present invention;

[0034] Figure 4 A circuit diagram of a data sensing circuit based on a radio frequency identification chip provided by an embodiment of the present invention;

[0035] Figure 5 A schematic diagram of another module of a data sensing circuit based on a radio frequency identification chip provided by an embodiment of the present invention;

[0036] Among them, 1. main control module, 2. signal receiving module, 3. data sensing module, 4. sensor start control module, 5. dummy load module, 6. impedance matching adjustment module, 7. storage module, 8. detection control module. DETAILED DESCRIPTION

[0037] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation method described herein is only an optimal embodiment of the present invention, which is only used to explain the present invention and does not limit the scope of protection of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0038] Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the operations (or steps) as sequential processes, many of the operations (or steps) therein can be implemented in parallel, concurrently, or simultaneously. In addition, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but can also have additional steps not included in the drawings; the process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0039] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. It should also be understood that in various embodiments of the present invention, the size of the sequence number of each process does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0040] It should be understood that in the present invention, "multiple" means two or more. "And / or" is just a variable relationship that describes the associated objects, indicating that there can be three relationships. "B corresponding to A" is similarly described to indicate that B is associated with A, and B can be determined based on A. Determining B based on A does not mean determining B based only on A, but B can also be determined based on A and / or other information. A and B match when the similarity between A and B is greater than or equal to a preset threshold.

[0041] Embodiment 1

[0042] Combination Figure 1 As shown, Figure 1A flow chart of a data sensing method based on a radio frequency identification chip is provided for one embodiment of the present invention. A data sensing method based on a radio frequency identification chip comprises the following steps:

[0043] S10, sending radio frequency signals to radio frequency identification chips of multiple sensing objects in the field area to power on and start sensing;

[0044] S20: Send a data reading instruction to the radio frequency identification chip through the reader / writer, wherein the data reading instruction carries the ID information of the sensing object.

[0045] S30. After the RFID chip corresponding to the ID information carried by the data reading command in the field area receives the data reading instruction, the sensor in the RFID chip obtains the detection data of the sensing object corresponding to the ID information, and transmits the detection data back to the reader / writer.

[0046] Specifically, the above-mentioned field area refers to the area where the sensing object is stored, including warehouses, workshops, etc. The above-mentioned sensing objects may include various mechanical devices, various retail goods, books, animals, etc. in the field area. The detection data of the sensing object may include sensing data, calibration data, etc. The sensing data may include temperature, product number, equipment status, etc., and the sensing data type may be different depending on the usage scenario. For example: obtaining the sensing data of generator a, including obtaining model specifications, power generation level, location information, power size, precautions, etc. The above-mentioned radio frequency identification chip may be an RFID passive sensor chip. By using radio frequency identification technology to obtain the detection data of the sensing object, the state tracking of the sensing object can be achieved, for example: obtaining the temperature data of the rotor of the hydro-turbine generator, controlling the speed of the rotor according to the temperature, and when the temperature reaches the preset temperature peak of 130°C, through temperature feedback, the speed of the hydro-turbine generator rotor is controlled to decrease to prevent the hydro-turbine generator rotor from being damaged by high temperature due to excessive temperature.

[0047] More specifically, the reader and the RFID chip communicate through an antenna to achieve signal transmission. When the requesting terminal needs to obtain the detection data of the sensing object, it sends a data request command to the reader, and the data request command includes the ID information of the sensing object to be obtained. The reader sends a radio frequency signal to the RFID chip of at least one sensing object in the field area, and the RFID chip is powered on to start sensing after receiving the radio frequency signal. After the RFID chip in the field area is powered on, the reader directly sends a data read instruction carrying the ID information of the sensing object to the RFID chip in the field area, where the ID information size is 16 bits. After the RFID chip in the field area receives the data read instruction, because the RFID chip carries the ID information of the sensing object, the sensing object can be confirmed according to the ID information carried in the data read instruction, and then the detection data of the sensing object is obtained through the sensor and returned to the reader. This process does not require the reader to send inventory instructions and write data to the slot counter of the RFID chip. It directly obtains the detection data of the sensing object by directly sending data reading instructions carrying ID information to complete a single sensing, which only takes about 8ms.

[0048] It should be noted that the requesting terminal in this application includes but is not limited to smart phones (such as Android phones, iOS phones, Windows Phone phones, etc.), tablet computers, PDAs, laptops, mobile Internet devices MID (Mobile Internet Devices) and other electronic devices. The above electronic devices are only examples, not exhaustive, and include but are not limited to the above electronic devices. In practical applications, the above electronic devices may also include computer devices, etc.

[0049] In the embodiment of the present invention, after the RFID chip is powered on, a data reading instruction carrying the ID information of the sensing object is directly sent to the RFID chip in the field area, and the detection data of the sensing object corresponding to the ID information in the field area is read and transmitted back to the reader / writer. A single sensing can be completed without the reader / writer sending an inventory instruction and writing data to the slot counter of the RFID chip. Compared with traditional sensing, the cumbersome inventory process is omitted, and the sensing speed can be accelerated and improved.

[0050] Optionally, the above step S10 specifically includes:

[0051] S101, the reader sends a radio frequency signal through a first antenna on the reader side;

[0052] S102, if the second antenna on the RFID chip side in the field area receives a RFID signal, the RFID signal is demodulated by a demodulator, and the demodulated signal obtained after demodulation is used as a start-up energy input for the RFID chip, and then powered on to start sensing, wherein the field area includes at least one RFID chip;

[0053] S103: If multiple RFID chips in the field receive activation energy that meets the activation condition, each RFID chip that meets the activation condition starts sensing.

[0054] Specifically, a radio frequency module and a first antenna are included at one end of the reader; a second antenna is connected to the radio frequency identification chip side, and the second antenna and the radio frequency identification chip constitute an electronic tag. After receiving the data request sent by the request terminal, the reader first sends a radio frequency signal of a specific frequency to the second antenna in the field area through the first antenna. When the second antenna on the radio frequency identification chip side enters the electromagnetic field of the effective working area generated by the first antenna, an induced current is generated, thereby obtaining the starting energy and being activated. Entering the power supply establishment period, the second antenna obtains the starting energy for the radio frequency identification chip, and demodulates the signal through the demodulator in the radio frequency identification chip, inputs the demodulated signal to the MCU of the circuit, and provides energy for the circuit. The above-mentioned starting condition can be an energy starting threshold. When the energy obtained reaches the energy starting threshold, the radio frequency identification chip starts sensing. Among them, the typical operating frequencies corresponding to the radio frequency signal include 125kHz, 225kHz, and 13.56MHz, the effective working area can be within 1m, and the sensing distance can be 10 to 20cm.

[0055] Optionally, the data read instruction includes an ACK instruction, and the above step S30 specifically includes:

[0056] S301, performing object matching in the field area according to the ID information of the sensing object carried in the ACK instruction, and determining the RFID chip corresponding to the ID information among the multiple RFID chips that have started sensing;

[0057] S302, acquiring detection data of the sensing object corresponding to the ID information through the sensor in the RFID chip corresponding to the ID information, and storing it in the memory EPC area in the RFID chip, reading the detection data from the memory EPC area through the ACK instruction, and transmitting the detection data back to the reader / writer.

[0058] Specifically, when the RFID chip receives the startup energy, the memory in the chip is powered on, and after entering the sensing stage, the detection data of the sensing object obtained by the sensor can be stored in the EPC area of ​​the memory. In some possible embodiments, if there are multiple tags entering the effective working area of ​​the reader, the sensing object corresponding to the ID information can also be quickly matched according to the ID information in the ACK instruction issued by the reader, so as to avoid obtaining wrong detection data.

[0059] More specifically, when the requesting terminal needs to synchronously obtain the detection data of multiple sensing objects, the ID information of multiple sensing objects can be carried in the ACK instruction, and each ID information can be represented by a different string. Then the ID information carried in the ACK instruction is matched with each RFID chip in the field area. When the ID information matches, it means that the match is successful, so as to determine the RFID chip corresponding to each ID information. The sensor in the determined RFID chip obtains the detection data of its sensing object and stores the detection data in the storage area EPC area. According to the ACK instruction, the reader / writer reads the detection data from the EPC area of ​​the storage area of ​​each determined RFID chip and transmits it back to the reader / writer. The detection data of multiple sensing objects can be stored in the reader / writer.

[0060] By directly sending an ACK command carrying ID information through the reader / writer, the sensor object to be found can be quickly matched and the detection data of the sensor object can be obtained and transmitted back to the reader / writer. There is no need for the reader / writer to send inventory instructions and write data to the slot counter of the RFID chip, which reduces the time of a single sensing.

[0061] Optionally, after the above step S30, the method further includes:

[0062] S40, when the ACK instruction includes ID information of multiple sensing objects and detection data of multiple sensing objects are obtained, a detection data sequence is constructed for the multiple detection data obtained in the reader according to the acquisition time;

[0063] S50, uploading the detection data sequence to the requesting terminal through the reader / writer.

[0064] Specifically, if the reader / writer obtains the detection data of multiple sensing objects synchronously at a single time, the RFID chip transmits the detection data of the sensing objects corresponding to the multiple ID information back to the reader / writer. In the reader / writer, all the returned detection data can be constructed into a detection data sequence according to the time when the detection data is obtained, or all the returned detection data can be constructed into a detection data sequence according to the time when the detection data is returned to the reader / writer. After the reader / writer obtains the detection data sequence, it feeds back the detection data sequence to the requesting terminal as a response to the data request command. Among them, when the reader / writer transmits the detection data sequence back, the detection data corresponding to each sensing object in the sequence includes ID information, which is convenient for the requesting terminal to identify the sensing object corresponding to each detection data.

[0065] Optionally, after the above step S40, the method further includes:

[0066] S60, determining in the reader whether all detection data corresponding to the ID information in the ACK instruction is obtained;

[0067] S70, if there is any unobtained detection data, an alarm message is generated and fed back to the requesting terminal, and a repeated ACK instruction is sent to the field area at least once, wherein the repeated ACK instruction includes the ID information of the unobtained sensing object;

[0068] S80. When the number of times the instruction is repeatedly sent reaches a predetermined threshold, the acquisition is terminated and the final acquisition result is transmitted back to the requesting terminal.

[0069] Specifically, in some embodiments, in the process of acquiring the sensing data of the sensing object, there may be a situation of sensing failure. Therefore, after a preset time period T, the reader can match the ID information of the acquired detection data with the ID information in the data request command sent by the request terminal to determine whether there is any detection data of the sensing object that has not been acquired. If so, an alarm message including the ID information of the sensing object that has not been acquired can be generated and sent to the request terminal. The request terminal can send a data acquisition request to the reader again, and the reader sends a repeated ACK instruction to the field area at least once, and re-executes the data acquisition action until it reaches a predetermined number of times. For example, the predetermined number of times is 3 times. If it is not acquired for 3 times, the process ends. If it is acquired within 3 times, the acquired detection data is added to the detection data sequence and transmitted back to the request terminal; or if it is acquired within 3 times, the detection data sequence constructed first is first uploaded to the request terminal, and the detection data acquired later is transmitted back to the request terminal separately. In this embodiment, in the case of missing detection data, repeated reading is performed at least once, which can ensure the integrity of the data return and better meet the needs of the requesting terminal.

[0070] Optionally, before returning the detection data to the reader / writer, the method further includes: performing an internal CRC check on the detection data.

[0071] Specifically, the CRC (Cyclic Redundancy Check) verification is also called cyclic redundancy verification. It is a channel coding technology that generates a short fixed-bit check code based on data such as network data packets or computer files. It is used to detect or verify errors that may occur after data transmission or storage. The sensor data in the detection data includes a verification bit, and the verification bit in the sensor data can be read and compared with the initial verification bit to determine whether it is consistent. If the verification is consistent, it can be said that the verification is passed, and the sensor data that passes the verification is returned to the reader; if the verification is inconsistent, it can be said that the sensor data is sent incorrectly during sensing, and the sensor data is not returned at this time. Among them, the types of verification validity can include data not being empty, sensor data not being disordered, etc. Therefore, by performing CRC verification internally, it is possible to avoid obtaining erroneous sensor data, thereby ensuring the accuracy of the sensor data of the sensor.

[0072] More specifically, combined Figure 2 As shown, Figure 2 A schematic diagram of the sensing process of a data sensing method based on an RFID chip provided in this embodiment. Wherein, CW is a continuous wave sent by the reader, Interrogator is a reader, Tag is a tag, ACK indicates an ACK command sent by the reader, NAK indicates a turn to cut, Select indicates tag selection, and Query Rep indicates a repeated query. After the reader communicates with the RFID chip, based on the different types of data stored in the RFID chip, a corresponding RF signal is sent to the RFID chip using the Select command to provide startup energy for the RFID chip, and the type of data to be read is determined according to the Select command, such as reading sensor data, calibration data, etc. The reader sends an ACK instruction carrying ID information to the RFID chip to read sensor data and calibration data. After receiving the ACK command, the RFID chip reads the sensor data and calibration data after an interval time of T1, and completes the reading at an interval time of T2 before returning the sensor data and calibration data, and returns the sensor data and calibration data to the reader, and the reader returns the sensor data to the requesting terminal. If the sensor data in the detection data is invalid, turn to NAK and turn to cut, and enter the waiting state.

[0073] Optionally, after the second antenna on the RFID chip side in the field area receives the RF signal, the method further includes: rectifying the RF signal through a rectifier in the RFID chip. In the RFID chip, after the second antenna receives the RF signal, the built-in rectifier rectifies the RF signal to achieve conversion from AC to DC, and outputs the DC power to other components in the RFID chip for use.

[0074] Embodiment 2

[0075] Combination Figure 3 As shown, Figure 3 A schematic diagram of a module of a data sensing circuit based on a radio frequency identification chip provided by an embodiment of the present invention. A data sensing circuit based on a radio frequency identification chip is applicable to a data sensing method based on a radio frequency identification chip, the circuit includes a main control module 1, a signal receiving module 2 and a data sensing module 3, the signal receiving module 2 and the data sensing module 3 are connected to the main control module 1, the circuit also includes: a sensor start control module 4, a dummy load module 5 and an impedance matching adjustment module 6, the sensor start control module 4 and the dummy load module 5 are respectively connected to the main control module 1, the impedance matching adjustment module 6 is connected to the signal receiving module 2, and the dummy load module 5 is also connected to the data sensing module 3.

[0076] Specifically, Figure 4 As shown, the main control module 1 includes a main control chip U1.

[0077] The sensor start control module 4 includes a TRIM controller U2 and a controller switch S1 with both ends connected to the TRIM controller U2. The TRIM controller U2 is connected to the main control chip U1. After the controller switch S1 is closed, the TRIM controller U2 outputs a sensor start signal to the main control chip U1.

[0078] The above-mentioned dummy load module 5 includes a dummy load sensor U3, a first load control switch S2, a second load control switch S3 and a first resistor R1; the first end of the dummy load sensor U3 is connected to one end of the second load control switch S3, the second end is connected to one end of the first load control switch S2, the third end is connected to one end of the data sensing module 3, and the fourth end is grounded; the second load control switch S3 is connected in series with the first resistor R1, and the other end of the first resistor R1 is connected to the other end of the first load control switch S2 and the other end of the data sensing module 3.

[0079] The signal receiving module 2 includes a modulator U5, a demodulator U6 and a rectifier U7. The modulator U5 and the demodulator U6 are connected to the impedance matching adjustment module 6, the rectifier U7 and the main control chip U1 respectively. The rectifier U7 is connected to the antenna ANT1 on the RFID chip side.

[0080] The data sensing module 3 includes a sensor U8 and a clock circuit Y1 connected to the sensor U8.

[0081] The impedance matching adjustment module 6 includes a plurality of impedance tuning units connected in parallel, wherein the first common end of each impedance tuning unit connected in parallel is connected to the antenna on the RFID chip side, and the second common end connected in parallel is respectively connected to the modulator, the demodulator and the rectifier, wherein the impedance tuning unit includes a first tuning subunit, a second tuning subunit and a third tuning subunit, wherein the first tuning subunit includes a first tuning switch S4 and a second resistor R2 connected in series, the second tuning subunit includes a second tuning switch S5 and a first capacitor C1 connected in series, and the third tuning subunit includes a third tuning switch S6 and a second capacitor C2 connected in series.

[0082] The radio frequency identification chip in this application is an RFID passive sensor chip. The main control chip U1 can be a baseband chip, which can be used to control the entire sensing work of the circuit, including controlling the acquisition of detection data, detection data storage, detection data transmission, circuit on-off control, etc.

[0083] More specifically, combined Figure 4 As shown, pin 1 of the TRIM controller U2 is connected to the DC voltage output by the rectifier U7, pin 3 is connected to pin 6 of the main control chip U1 to output the sensing start signal, and pin 4 is grounded. Both ends of the controller switch S1 are directly connected to the TRMI controller U2. After pin 1 of the TRIM controller U2 receives the DC voltage output by the rectifier U7, the controller switch S1 is turned on, and the TRMI controller U2 outputs the sensing start signal to the main control chip U1 through pin 3. The main control chip U1 quickly opens the data transmission channel between each chip according to the received sensing start signal and enters the sensing stage.

[0084] More specifically, combined Figure 4 As shown, pin 1 (first end) of the dummy load sensor U3 is connected to one end of the second load control switch S3; pin 2 (second end) of the dummy load sensor U3 is connected to one end of the first load control switch S2, the other end of the second load control switch S3 is connected to the first resistor R1 and then connected to the other end of the first load control switch S2 to the sensor U8 and the pin 8 of the main control chip U1; pin 3 (third end) of the dummy load sensor U3 is connected to the clock circuit Y1; pin 4 (fourth end) of the dummy load sensor U3 is grounded.

[0085] Combination Figure 4As shown, the pin 1 of the dummy load sensor U3 is also connected to the power supply voltage. After receiving the power supply voltage, due to the long sensing time of the sensor U8, when the sensor U8 is in the process of preparing to start sensing in the sensing stage, the dummy load sensor U3 replaces the sensor U8 to work. At this time, the first load control switch S2 is turned on, and the impedance matching calculation of the sensing stage is performed according to the main control chip U1, the signal receiving module 2, the sensing start control module 4, and the dummy load module 5 that have entered the working state. According to the impedance size obtained by matching, the impedance is adjusted through the impedance matching adjustment module 6, and an impedance configuration of the sensing stage is generated. Secondly, when the second load control switch S3 is controlled to be turned on, the voltage at both ends of the first resistor R1 can be detected, thereby obtaining the line voltage of the dummy load sensor U3. Impedance matching is performed by replacing sensor U8 with a dummy load sensor U3. When sensor U8 enters the sensing stage, based on the impedance configuration corresponding to the sensing stage generated in advance, sensor U8 does not need to spend more time on impedance matching. Instead, it can directly find the sensor data and calibration data corresponding to the ID information in the ACK instruction based on the ID information in the reader / writer, and return them to the reader / writer, which is beneficial to reducing the time to complete a single sensing.

[0086] The sensor U8 is used to obtain the detection data of the detection object, and the detection data includes sensor data, calibration data, etc. The sensor data includes temperature data, product number data, device status, calibration data, etc. The sensor data type varies according to different usage scenarios. The sensor U8 may include a temperature sensor, a humidity sensor, etc. The clock circuit Y1 can ensure that the sensor U8 starts working in an orderly manner based on the timing after being powered on.

[0087] More specifically, combined Figure 4 As shown, the modulator U5 and demodulator U6 can perform signal conversion on the received RF signal or the signal output by the main control chip U1, including the conversion between digital signal and analog signal. The rectifier U7 is used to rectify the signal connected to the antenna ANT1, convert the AC power into DC power VCC, and provide DC power for each chip in the circuit, including providing DC power for the main control chip U1, TRIM controller U2, dummy load sensor U3, memory U4, modulator U5, demodulator U6, and sensor U8. Pin 3 of the modulator U5 is connected to pin 2 of the main control chip U1, and pin 3 of the demodulator U6 is connected to pin 3 of the main control chip U1. The modulator U5 and the demodulator U6 modulate and demodulate the RF signal sent by the reader or the control signal output by the main control chip U1 to realize the transmission of the modulated and demodulated signal.

[0088] More specifically, combined Figure 4As shown, multiple impedance tuning units in the impedance matching adjustment module 6 are connected in parallel, and one common end of the two ends of the parallel connection is connected to the antenna ANT2, and the other common end is connected to the DC pin AC of the rectifier U7, the pin 2 of the modulator U5 and the pin 2 of the demodulator U6. In the sensing stage, when the dummy load sensor U3 replaces the sensor U8 for impedance matching, the impedance of the sensing stage can be adjusted by turning on any one or more of the first tuning switch S4, the second tuning switch S5 or the third tuning switch S6, and any one or more of the first capacitor C1, the second capacitor C2 or the second resistor R2 are connected to the circuit to generate an impedance configuration for the sensing stage, so that the signal source or transmission line is adapted to the load, so that the sensor U8 can quickly start working and start sensing when entering the sensing stage. And when the sensor U8 enters the sensing stage, the main control chip U1 can send a control signal to control the first load control switch S2 and the second load control switch S3 connected to the dummy load sensor U3 to disconnect. When the impedance of the circuit is in a relatively small state, more tuning switches can be disconnected to reduce the capacitors connected to the circuit; when the impedance of the circuit is in a relatively large state, multiple tuning switches can be turned on to increase the capacitors connected to the circuit to adjust the optimal state of the circuit impedance in the sensing stage. The capacitance values ​​of the first capacitor C1 and the second capacitor C2 can be the same or different. The antenna ANT1 and the antenna ANT2 can be the same antenna.

[0089] Optionally, combined Figure 4 and Figure 5 As shown, the circuit further includes a storage module 7, which is connected to the main control module 1. The storage module 7 includes a memory U4 and a clock circuit Y2 connected to the memory U4.

[0090] Optionally, pin 3 of the above-mentioned memory U4 is connected to pin 9 of the main control chip U1. When the sensor U8 sends the acquired sensor data to the main control chip U1, the main control chip U1 can send the sensor data of the detected object to the memory U4 for storage. When the reader wants to read the sensor data, it sends an ACK instruction to the radio frequency identification chip to obtain the sensor data stored in the memory U4, and returns it to the terminal device that issued the request. The clock circuit Y2 can synchronize the timing for the memory U4 to ensure the orderliness of the storage work. Similarly, the main control chip U1 is connected to the clock circuit Y3 to ensure orderly operation based on the timing after power-on.

[0091] Optionally, combined Figure 4 and Figure 5 As shown, the circuit also includes a detection control module 8, which includes a first sensor control switch, a second sensor control switch, a third resistor and a current source. The first sensor control switch is connected in series with the third resistor and then connected between the main control module 1 and the data sensor module 3. The second sensor control switch is connected in series with the current source and then connected in parallel at both ends of the first sensor control switch and the third resistor.

[0092] Specifically, the detection control module 8 can be used to control the conduction between the sensor U8 or the dummy load sensor U3 and the main control chip U1 to build a data sensing channel. It can also be disconnected when the sensor U8 obtains sensor data abnormally to avoid the transmission of erroneous data. Abnormal sensor data can be judged through internal verification.

[0093] The first sensor control switch S7 is connected in series with the third resistor R3 between the pin 2 of the sensor U8 and the pin 8 of the main control chip U1. One end of the second sensor control switch S8 is connected to the positive electrode of the current source A, and the other end is connected to the pin 8 of the main control chip U1 together with the first sensor control switch S7; the negative electrode of the current source A and the third resistor R3 are connected to the pin 2 of the sensor U8. The first sensor control switch S7 and the second sensor control switch S8 are turned on in a selective manner. When the first sensor control switch S7 is turned on, the ADC signal flowing through the third resistor R3 is measured in the form of a resistor divider. When the second sensor control switch S8 is turned on, the ADC signal flowing through the current source A is measured in the form of a DC power supply.

[0094] Optionally, combined Figure 4 As shown, the circuit also includes a voltage stabilizer, one end of which is input with power, and the other end of which is connected with the data sensing module 3.

[0095] Specifically, the pin 1 of the voltage regulator U9 is connected to the power supply voltage, and after the voltage regulator U9 stabilizes the voltage, a stable output voltage is output from the pin 3 of the voltage regulator U9 to the pin 2 of the sensor U8 of the data sensor module 3 and the dummy load sensor U3. Regardless of how the power supply voltage or the load conditions in the RFID sensor chip change, the voltage regulator U9 can generate and maintain a fixed output voltage to ensure stable operation of the sensor U8.

[0096] Optionally, combined Figure 4 As shown, pin 7 of the main control chip U1 can also be connected to a low-frequency interface J1, which can connect the main control chip U1 to interfaces of other circuit boards or electronic devices for transmitting low-frequency signals while ensuring signal quality and stability.

[0097] In an embodiment of the present invention, a sensor start control module 4 is connected to the main control chip U1 in the sensor circuit. When the radio frequency identification chip receives the radio frequency signal sent by the reader, the TRIM controller U2 in the sensor start control module 4 receives the DC power supply converted by the rectifier U7 to output the radio frequency signal, and the controller switch S1 connected to the TRIM controller U2 is turned on. At this time, the TRIM controller U2 outputs a sensor start signal to the main control module 1, and the main control chip U1 starts the transmission channel with each chip based on the sensor start signal, which is conducive to quickly starting the sensing process. In addition, considering that the sensing startup process of the sensor U8 is long and slow, during the buffering process before the sensor U8 starts sensing, the dummy load sensor U3 and the impedance matching adjustment module 6 are connected in the circuit at the same time. Before the sensor U8 starts sensing, the dummy load sensor U3 replaces the sensor U8, calculates the impedance of each module involved in the circuit during the sensing stage, and performs corresponding impedance matching adjustment through the impedance matching adjustment module 6. When the sensor U8 enters the sensing stage, based on the impedance configuration corresponding to the sensing stage generated in advance, the sensor U8 does not need to spend more time on impedance matching, which is beneficial to reduce the time to complete a single sensing.

[0098] The above specific implementation is a preferred implementation of a data sensing method based on a radio frequency identification chip of the present invention, and is not intended to limit the specific implementation scope of the present invention. The scope of the present invention includes but is not limited to this specific implementation. All equivalent changes made in accordance with the shape and structure of the present invention are within the protection scope of the present invention.

Claims

1. A data sensing circuit based on a radio frequency identification chip, comprising a main control module, a signal receiving module and a data sensing module, wherein the signal receiving module and the data sensing module are connected to the main control module, characterized in that: The circuit further includes: a sensor start control module, a dummy load module and an impedance matching adjustment module, wherein the sensor start control module and the dummy load module are respectively connected to the main control module, the impedance matching adjustment module is connected to the signal receiving module, and the dummy load module is also connected to the data sensor module; The sensor start control module includes a TRIM controller U2, and a controller switch S1 whose two ends are respectively connected to the TRIM controller U2. The TRIM controller U2 is connected to the main control chip U1. After the controller switch S1 is closed, the TRIM controller U2 outputs a sensor start signal to the main control chip U1. The dummy load module includes a dummy load sensor U3, a first load control switch S2, a second load control switch S3 and a first resistor R1; a first end of the dummy load sensor U3 is connected to one end of the second load control switch S3, a second end is connected to one end of the first load control switch S2, a third end is connected to one end of the data sensor module, and a fourth end is grounded; The second load control switch S3 is connected in series with the first resistor R1, and the other end of the first resistor R1 is connected to the other end of the first load control switch S2; The signal receiving module includes a modulator U5, a demodulator U6 and a rectifier U7. The modulator U5 and the demodulator U6 are both connected to the impedance matching adjustment module, the rectifier U7 and the main control chip U1. The rectifier U7 is connected to the antenna ANT1 on the RFID chip side. The data sensing module includes a sensor U8 and a clock circuit Y1 connected to the sensor U8; The impedance matching adjustment module includes multiple impedance tuning units connected in parallel, and the first common end of each impedance tuning unit connected in parallel is connected to the antenna ANT2 on the radio frequency identification chip side, and the second common end connected in parallel is respectively connected to the modulator U5, the demodulator U6 and the rectifier U7, wherein the impedance tuning unit includes a first tuning subunit, a second tuning subunit and a third tuning subunit, the first tuning subunit includes a first tuning switch S4 and a second resistor R2 connected in series, the second tuning subunit includes a second tuning switch S5 and a first capacitor C1 connected in series, and the third tuning subunit includes a third tuning switch S6 and a second capacitor C2 connected in series.

2. A data sensing circuit based on a radio frequency identification chip as claimed in claim 1, characterized in that: The circuit also includes a storage module, which is connected to the main control module. The storage module includes a memory and a clock circuit Y2 connected to the memory.

3. A data sensing method based on a radio frequency identification chip, applicable to a data sensing circuit based on a radio frequency identification chip as claimed in claim 1, characterized in that: The following steps are involved: Sending radio frequency signals to the radio frequency identification chips of multiple sensing objects in the field area to power on and start sensing; Sending a data reading instruction to the RFID chip through a reader / writer, wherein the data reading instruction carries the ID information of the sensing object; When the RFID chip corresponding to the ID information carried by the data reading command in the field area receives the data reading instruction, the sensor U8 in the RFID chip obtains the detection data of the sensing object corresponding to the ID information, and transmits the detection data back to the reader; The method of sending radio frequency signals to radio frequency identification chips of multiple sensing objects in the field area to power on and start sensing includes: The reader sends the radio frequency signal through a first antenna on the reader side; If the second antenna on the RFID chip side in the field area receives the RF signal, the RF signal is demodulated by the demodulator U6, and the demodulated signal obtained after demodulation is used to input the start-up energy to the RFID chip, and the sensor start-up control module is powered on to start the sensor, wherein the field area includes at least one RFID chip; If a plurality of the RFID chips in the field receive activation energy that meets the activation condition, each of the RFID chips that meets the activation condition starts sensing.

4. A data sensing method based on a radio frequency identification chip as claimed in claim 3, characterized in that: The data reading instruction includes an ACK instruction, and the sensor U8 in the radio frequency identification chip obtains the detection data of the sensing object corresponding to the ID information, and transmits the detection data back to the reader, including: Performing object matching in the field according to the ID information of the sensing object carried in the ACK instruction, and determining the RFID chip corresponding to the ID information among the plurality of RFID chips that have started sensing; The sensor U8 in the RFID chip corresponding to the ID information obtains the detection data of the sensing object corresponding to the ID information, and stores it in the memory EPC area in the RFID chip. The detection data is read from the memory EPC area through the ACK instruction, and the detection data is transmitted back to the reader / writer.

5. A data sensing method based on a radio frequency identification chip as claimed in claim 4, characterized in that: After transmitting the detection data back to the reader / writer, the method further includes: When the ACK instruction includes the ID information of multiple sensing objects and the detection data of multiple sensing objects are obtained, a detection data sequence is constructed for the multiple detection data obtained according to the acquisition time in the reader; The detection data sequence is uploaded to the requesting terminal through the reader / writer.

6. A data sensing method based on a radio frequency identification chip as claimed in claim 5, characterized in that: After constructing a detection data sequence for the acquired multiple detection data in the reader according to the acquisition time, the method further includes: Determine in the reader whether all detection data corresponding to the ID information in the ACK instruction is obtained; If there is any unobtained detection data, an alarm message is generated and fed back to the request terminal, and a repeated ACK instruction is sent to the RFID chip in the field at least once, wherein the repeated ACK instruction includes the ID information of the unobtained sensing object; When the number of times the instruction is repeatedly sent reaches a predetermined threshold, the acquisition is terminated, and the final acquisition result is transmitted back to the requesting terminal through the reader / writer.

7. A data sensing method based on a radio frequency identification chip as claimed in claim 3, characterized in that: After the second antenna on the RFID chip side in the field area receives the RF signal, the method further includes: rectifying the RF signal by a rectifier in the RFID chip.

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