A flexible environment monitoring device and method integrating multi-frequency antenna and energy harvesting

Abstract

The present invention relates to a flexible environment monitoring device and method integrating multi-frequency antenna and energy collection. Through an improved energy collection module, the energy collection transmission efficiency is improved, the charging time is reduced, and the collected energy is utilized to the maximum extent. At the same time, the integrated multi-frequency antenna avoids mutual crosstalk between antennas, ensuring the correct transmission of information. Through the radio frequency information detection instruction sent by the client, the data processing and control module drives the sensor module to collect information when the energy collection module is normally powered and feeds back real-time environmental information to the client through the radio frequency information transmission module, ultimately ensuring the normal and stable operation of the cold chain process.

Description

Technical Field

[0001] The present invention relates to the field of agricultural product cold chain transportation environment monitoring and flexible electronic sensor technology, and in particular to a flexible environment monitoring device and method integrating a multi-frequency antenna and energy collection. Background Art

[0002] As consumers' demand for high-quality agricultural products gradually increases, higher requirements are placed on environmental monitoring during the cold chain process. Traditional rigid sensors based on PCB boards occupy the limited volume in agricultural product packaging due to their large volume and mass, reducing the effective utilization rate of the packaging. In particular, the long-term battery power supply required during the cold chain sealing process further increases the size and weight of the monitoring device, and may cause secondary damage due to vibration during transportation, thus affecting the quality of agricultural products.

[0003] How to improve the size and weight of the sensor monitoring device and provide long-term safe and effective power supply is a great challenge. Energy harvesting based on solar cells or RFID technology can effectively reduce the volume and weight of the monitoring device, but the complex environment of low temperature and high humidity in the cold chain process seriously affects the continuous energy harvesting, and there are problems such as long charging time and the harvested energy cannot drive the normal operation of the sensor. Therefore, it is urgent to propose a new flexible printing and energy harvesting transmission method to adapt to the complex environment of the cold chain process to achieve passive and low power consumption functions, reduce the size of the monitoring device and make it easy to attach to the inside of the package while enhancing the energy transmission efficiency and improving the energy storage performance to achieve stable and sustainable intelligent monitoring of the cold chain environment. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, an object of the present invention is to provide a flexible environment monitoring device and method integrating a multi-frequency antenna and energy harvesting.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A flexible environment monitoring device integrating multi-frequency antenna and energy collection, comprising: an energy collection module, a multi-parameter sensing module, a radio frequency information transmission module, a data processing and control module and a client; the energy collection module, the multi-parameter sensing module, the radio frequency information transmission module and the data processing and control module are all printed on a flexible PET substrate by flexible printing technology;

[0007] The energy collection module is connected to the data processing and control module and the multi-parameter sensing module respectively, and the energy collection module is used to collect natural energy and / or radio frequency energy and store and supply power; the radio frequency energy is converted by the HF chip in the energy collection module to realize the collection of the radio frequency energy; the multi-parameter sensing module is connected to the data processing and control module, and the multi-parameter sensing module is used to collect environmental data in real time and transmit it to the data processing and control module for subsequent data processing, analysis, transmission and display; the data processing and control module, the radio frequency information transmission module and the client are connected in sequence, and the data processing and control module is used to The radio frequency information transmission module is used to realize real-time interconnection between the client and the sensor monitoring device, and send the processed data to the client; the client is also connected to the energy acquisition module, and the client is used to send an instruction to collect signals to the data processing and control module through the radio frequency information transmission module, and send the radio frequency energy to the energy acquisition module, and control the working status of the data processing and control module and the multi-parameter sensor module, and also display the environmental information in real time according to the processed data, and notify the management personnel to carry out early warning and regulation when the environmental information is abnormal.

[0008] Preferably, the energy collection module comprises a solar energy collection submodule;

[0009] The solar energy collection submodule includes a light detector, a solar cell, a supercapacitor and a voltage monitor connected in sequence; the light detector is used to detect whether there is light that satisfies the solar energy sensing layer to collect light energy, and if so, sends a collection signal to the solar cell; the solar cell is used to convert the collected light energy into electrical energy and store it; the supercapacitor is used to store the electrical energy; the voltage monitor is used to monitor the voltage state of the supercapacitor and adjust the working state of other modules according to the information obtained from the monitoring.

[0010] Preferably, the energy harvesting module comprises a radio frequency energy harvesting submodule;

[0011] The RF energy collection submodule includes a resonator, an HF antenna, an impedance matching network, an HF chip, a rectifier and filter circuit, a boost circuit, a voltage monitor and a supercapacitor connected in sequence; the RF energy collection submodule is used to collect RF energy through RF energy collection technology when the illumination does not meet the requirements of the solar energy sensing layer to collect illumination energy, resulting in the voltage monitor monitoring the supercapacitor voltage unable to meet the sensor working voltage, and convert and process the RF energy and store it in the supercapacitor.

[0012] Preferably, the energy transmission efficiency from the energy emitted by the client to the energy collected by the HF chip is:

[0013] Among them, S 31 is the scattering parameter between the transmitting antenna and the receiving antenna, S 21 is the scattering parameter between the transmitting antenna and the resonator, S 32 is the scattering parameter between the resonator and the receiving antenna; S 31 , S 21 and S 32 Obtained through the following model:

[0014]

[0015] Among them, I 2 ,I 3 I respectively represent the receiving current of the resonator and the receiving end at a frequency of 13.56 MHz; 1 ,I 2 and I 3 The calculation formula is:

[0016]

[0017] Among them, M 12 、M 13 、M 23 They are the mutual inductance between the transmitting antenna and the resonator, the mutual inductance between the transmitting antenna and the receiving antenna, and the mutual inductance between the resonator and the receiving antenna: Among them, k iy is the coupling coefficient between the transmitting antenna, the resonator and the receiving antenna; ω is the resonant angular frequency, Q i Represents the quality factor at the transmitter, resonator and receiver, L i They represent the equivalent self-inductance changes of the transmitting antenna, resonator and receiving antenna, respectively, and Z i Indicates the impedance changes, specifically: Among them, R S is the resistance of the transmitting antenna power supply terminal, R Tx is the equivalent resistance of the transmitting antenna, R R is the resonator equivalent resistance, R L is the receiving end load resistance, R RX is the equivalent resistance of the receiving antenna, X i is the reactance change of the transmitting antenna, resonator and receiving antenna; V s is the source voltage at the transmitting end;

[0018] The capacitor and resistor in the matching network form an RLC resonant circuit with the HF antenna.

[0019] Preferably, the data processing and control module includes a microcontroller, a signal amplifier and an AD converter;

[0020] The microcontroller is used to receive information from the radio frequency information transmission module, send instructions to the multi-parameter sensing module, and transmit the sensing information collected by the multi-parameter sensing module to the signal amplifier; the signal amplifier is used to amplify and filter the information; the AD converter is used to convert the amplified and filtered sensing information, and transmit the converted information to the client through the radio frequency information transmission module.

[0021] Preferably, the method of printing the multi-parameter sensing module, the radio frequency information transmission module, the data processing and control module and the energy collection module into the flexible PET substrate is:

[0022] The first layer of interconnection circuits and NFC antennas were printed using nanosilver ink by inkjet printing and cured in an electric constant temperature drying oven at 100°C for 45 minutes, wherein the antenna was printed twice and the circuit conductors were printed three times;

[0023] The insulating ink with a thickness of 100 μm is applied to the position where the first layer needs to be superimposed by the dispensing method, and then cured by 365 nm UV light and then cured in an electric constant temperature drying oven at 80°C for 30 min;

[0024] Print the designed interconnection wires on the insulating layer, and according to the size design and packaging requirements of each electronic component, place the chip in the corresponding position and solder the screen-printed conductive silver glue on the prepared interconnection wires by heating and reflowing at 80°C, then cool to room temperature, and then cure at room temperature for 30 minutes;

[0025] The PDMS film was attached to the integrated circuit as an encapsulation layer and cured at 60 degrees for 1 hour.

[0026] Preferably, the multi-parameter sensing module includes a temperature sensor, a humidity sensor, an ammonia sensor and a pressure sensor.

[0027] Preferably, the method of printing the temperature sensor, the humidity sensor, the ammonia sensor and the pressure sensor into the flexible PET substrate is:

[0028] Printing the sensing electrodes of the temperature sensor, the humidity sensor, the ammonia sensor and the pressure sensor on the flexible PET substrate by inkjet printing technology, and sintering at 120° C. for 30 min;

[0029] The sensitive indicator sensing layers are scraped onto the flexible electrode and sintered at 120°C for 60 minutes.

[0030] The interconnection between the multi-parameter sensing module and the data processing and control module is achieved through SPI serial communication technology.

[0031] Preferably, the client includes an NFC communication module, an RFID reader / writer, a control center, a user interaction module and a display module;

[0032] The NFC communication module is used to send energy collection information to the energy collection module; the RFID reader is used to issue data collection instructions to the radio frequency information transmission module and transmit them to the data processing and control module; the control center, the user interaction module and the display module are used to perform real-time interaction and visual display based on the sensed information, and feed back abnormal data to the user.

[0033] Preferably, in order to maximize the utilization of energy collection efficiency, the data processing and control module controls the entire monitoring device to have three working states: working mode, transmission mode and sleep mode. When the multi-parameter monitoring module is awakened by the data processing and control module for data collection and transmission, it is in the working state. At this time, all modules are in the normal working mode, and its working current is about 20mA / ms; when the radio frequency transmission module is controlled by the data processing and control module to interact with the client through backscattering, it is in the transmission mode. At this time, the multi-parameter monitoring module is turned off, and only the information communication function of the data processing and control module and the radio frequency transmission module is retained. Its working current is about 14mA / ms; finally, when it is in an inactive state, it is in a low-power sleep state, and all modules only retain basic functions such as timers, and their working current is about 3mA / ms. Among them, the energy collection module is not affected by the working state. It notifies the data processing and control module through the voltage monitor and provides the energy information basis for the data processing and control module to determine which working state. When the monitored voltage value is lower than the highest threshold voltage, energy collection continues, and when the monitored voltage value reaches the highest threshold voltage, the energy collection module is turned off.

[0034] A flexible environmental monitoring method integrating multi-frequency antenna and energy harvesting is applied to the above agricultural product environmental monitoring device, and the method comprises:

[0035] The NFC communication module of the client is used to send an energy collection signal to the RF energy collection module. The HF antenna improves the energy collection efficiency through the resonator. The HF chip and the HF antenna improve the energy collection efficiency again through the impedance matching network. The collected RF energy is converted into direct current through the rectifier circuit and the weak direct current is amplified through the boost circuit to achieve boost processing and store the collected energy in the supercapacitor. At the same time, the light detection module detects whether there is light to meet the solar energy sensing layer to collect light energy. When the conditions are met, energy conversion is performed and the collected solar energy is stored in the supercapacitor.

[0036] The energy collected by the supercapacitor is monitored by a voltage monitor. When the voltage in the supercapacitor reaches the working voltage of the data processing and control module, the data processing and control module is turned on and communicates with the client through the radio frequency information transmission module. The client sends a data collection instruction to the radio frequency communication module through the RFID reader and transmits it to the data processing and control module. When the voltage in the supercapacitor reaches the working voltage of the sensor, the data processing and control module sends an environmental monitoring instruction to the multi-parameter sensing module and amplifies, filters and performs AD conversion on the data information collected by the multi-parameter sensing module and feeds it back to the client display module through the radio frequency information transmission module for real-time display and sends abnormal information to the user interaction module to remind the user.

[0037] After the data transmission is completed, the multi-parameter sensing module, the data processing and control module and the radio frequency information transmission module are closed in sequence. At the same time, the voltage monitor continues to monitor the supercapacitor voltage. When the voltage reaches the highest threshold voltage, charging is stopped and the next environmental monitoring instruction is waited for. Otherwise, the capacitor voltage is monitored to see if it reaches the working voltage of the sensing module. When the capacitor voltage reaches the working voltage of the sensing module, charging is continued and the next environmental monitoring instruction is waited for. Otherwise, the capacitor voltage is monitored to see if it reaches the working voltage of the data processing and control module. When the capacitor voltage reaches the working voltage of the data processing and control module, charging is continued and the data processing and control module is turned on to wait for the next environmental monitoring instruction. Otherwise, the capacitor voltage is monitored to see if it reaches the lowest threshold voltage. When the capacitor voltage reaches the lowest threshold voltage, charging is continued and the data processing and control module is turned on.

[0038] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0039] The present invention provides a flexible environment monitoring device and method integrating multi-frequency antenna and energy collection, the device comprising: an energy collection module, a multi-parameter sensing module, a radio frequency information transmission module, a data processing and control module and a client; the energy collection module, the multi-parameter sensing module, the radio frequency information transmission module and the data processing and control module are all printed on a flexible PET substrate by flexible printing technology; the energy collection module is respectively connected to the data processing and control module and the multi-parameter sensing module, the energy collection module is used to collect natural energy and / or radio frequency energy and store and supply power; the radio frequency energy is collected by an RLC resonant circuit in the energy collection module; the multi-parameter sensing module The module is connected to the data processing and control module, and the multi-parameter sensing module is used to collect environmental data in real time and transmit it; the data processing and control module, the radio frequency information transmission module and the client are connected in sequence, the data processing and control module is used to process the environmental data, and the radio frequency information transmission module is used to send the processed data to the client; the client is also connected to the energy collection module, and the client is used to send the radio frequency energy to the energy collection module, and control the working state of the data processing and control module and the multi-parameter sensing module, and also display the environmental information in real time according to the processed data, and issue an early warning when the environmental information is abnormal. The present invention improves the energy collection and transmission efficiency, reduces the charging time, and maximizes the use of the collected energy through an improved energy collection module. At the same time, the integrated multi-frequency antenna avoids mutual crosstalk between antennas, ensures the correct transmission of information, and through the radio frequency information detection instruction sent by the client, the data processing and control module drives the sensing module to collect information under the condition that the energy collection module is normally powered and feeds back real-time environmental information to the client through the radio frequency information transmission module, ultimately ensuring the normal and smooth operation of the cold chain process. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0041] Figure 1 A schematic diagram of the overall structure of an embodiment provided by the present invention;

[0042] Figure 2 A conceptual diagram of a radio frequency energy harvesting circuit model in an embodiment of the present invention;

[0043] Figure 3 It is a schematic diagram of the overall process in the embodiment provided by the present invention. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0046] The terms "first", "second", "third" and "fourth" in the specification and claims of the present application and the drawings are used to distinguish different objects rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a series of steps, processes, methods, etc. are not limited to the listed steps, but may optionally include steps that are not listed, or may optionally include other step elements inherent to these processes, methods, products or devices.

[0047] The purpose of the present invention is to provide a flexible environmental monitoring device and method integrating multi-frequency antennas and energy harvesting, which can improve the energy harvesting transmission efficiency, reduce the charging time, and maximize the utilization of the harvested energy. At the same time, the integrated multi-frequency antenna avoids crosstalk between antennas to ensure the correct transmission of information. Through the radio frequency information detection instructions sent by the client, the data processing and control module drives the sensor module to collect information when the energy harvesting module is normally powered and feeds back real-time environmental information to the client through the radio frequency information transmission module, ultimately ensuring the normal and smooth operation of the cold chain process.

[0048] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0049] In this embodiment, the transportation process of aquatic products is taken as an example, specifically the transportation process of oysters and fish.

[0050] Figure 1 The overall structure diagram of the embodiment provided by the present invention is as follows: Figure 1As shown, the present invention provides a flexible environment monitoring device integrating multi-frequency antenna and energy collection, comprising: an energy collection module, a multi-parameter sensing module, a radio frequency information transmission module, a data processing and control module and a client; the energy collection module, the multi-parameter sensing module, the radio frequency information transmission module and the data processing and control module are all printed on a flexible PET substrate by flexible printing technology;

[0051] The energy collection module is connected to the data processing and control module and the multi-parameter sensing module respectively, and the energy collection module is used to collect natural energy and / or radio frequency energy and store and supply power; the radio frequency energy is converted by the HF chip in the energy collection module to realize radio frequency energy collection; the multi-parameter sensing module is connected to the data processing and control module, and the multi-parameter sensing module is used to collect environmental data in real time and transmit it; the data processing and control module, the radio frequency information transmission module and the client are connected in sequence, the data processing and control module is used to process the environmental data, and the radio frequency information transmission module is used to send the processed data to the client; the client is also connected to the energy collection module, and the client is used to send the radio frequency energy to the energy collection module, and control the working status of the data processing and control module and the multi-parameter sensing module, and also display the environmental information in real time according to the processed data, and issue an early warning when the environmental information is abnormal.

[0052] Specifically, the energy collection module, multi-parameter sensing module, radio frequency information transmission module, and data processing and control module are all printed on a flexible PET substrate through flexible printing technology, and packaging technology is used to adapt to the complex environment of low temperature and high humidity in the cold chain process. The energy collection module is used to collect natural / radio frequency energy from the environment or the client to drive the normal operation of the data processing and control module and the multi-parameter sensing module, thereby improving energy collection efficiency and reducing charging time;

[0053] Preferably, the energy collection module comprises a solar energy collection submodule;

[0054] The solar energy collection submodule includes a light detector, a solar cell, a supercapacitor and a voltage monitor connected in sequence; the light detector is used to detect whether there is light that satisfies the solar energy sensing layer to collect light energy, and if so, sends a collection signal to the solar cell; the solar cell is used to convert the collected light energy into electrical energy and store it; the supercapacitor is used to store the electrical energy; the voltage monitor is used to monitor the electrical energy of the supercapacitor and adjust the working status of other modules according to the information obtained from the monitoring.

[0055] In this embodiment, the specific preparation process of the flexible solar cell includes: ultrasonically cleaning PET, scraping SOLA-TE07Z solution on the flexible film, and then annealing at 80°C for 10 minutes to obtain an electron transport layer; then scraping active layer solution on the film, annealing at 100°C for 10 minutes to obtain a light absorption layer; then scraping SOLA-TH302 solution, annealing at 120°C for 15 minutes to obtain a hole transport layer, and finally printing interdigitated electrodes by inkjet printing technology to obtain a flexible solar cell, which improves the defects of large size and heavy weight of the previous battery module;

[0056] Preferably, the energy harvesting module comprises a radio frequency energy harvesting submodule;

[0057] The RF energy collection submodule is connected to the client, the light detector and the supercapacitor respectively. The RF energy collection submodule is used to collect RF energy through RF energy collection technology when the light does not meet the requirements of the solar sensor layer to collect light energy, and convert and process the RF energy and store it in the supercapacitor.

[0058] Preferably, the RF energy harvesting submodule comprises a resonator, an HF antenna, an impedance matching network, an HF chip, a rectifier circuit, a boost circuit, a supercapacitor and a voltage monitor connected in sequence;

[0059] Specifically, the radio frequency energy collection module is used to collect radio frequency energy through radio frequency transmission technology when there is no light and the solar energy collection module cannot work normally, convert AC voltage into DC voltage through the rectifier module, and use the boost module to boost the converted weak voltage, and store the collected energy in the supercapacitor to ensure the normal operation of the environmental monitoring device for power supply;

[0060] The resonator, HF antenna, impedance matching network and HF chip are used to improve the energy collection efficiency. The RF energy collection circuit model is as follows: Figure 2 As shown, it includes a transmitting end, a resonator, and a receiving end; wherein the receiving end includes a receiving antenna and an impedance matching network; wherein V s is the source voltage at the transmitter, R S is the resistance of the transmitting antenna power supply terminal, R Tx is the equivalent resistance of the transmitting antenna, C Tx is the equivalent capacitance of the transmitting antenna, L Tx is the transmitting antenna equivalent self-inductance, R R is the resonator equivalent resistance, C R is the resonator equivalent capacitance, L R is the equivalent self-inductance of the resonator, R L is the receiving end load resistance, R RX is the equivalent resistance of the receiving antenna, CRx is the equivalent capacitance of the receiving antenna, L Rx is the equivalent self-inductance of the receiving antenna; the equivalent capacitance and equivalent self-inductance of the transmitting antenna, resonator and receiving antenna form reactance changes, which are represented by X 1 , X 2 , X 3 Indicates; eventually forms Z i Indicates the impedance changes, specifically:

[0061] Among them, Z 1 , Z 2 and Z 3 Respectively represent the impedance changes at the transmitting antenna, resonator and receiving antenna; M 12 、M 13 、M 23 They are the mutual inductance coefficient between the transmitting antenna and the resonator, the mutual inductance coefficient between the transmitting antenna and the receiving antenna, and the mutual inductance coefficient between the resonator and the receiving antenna; Among them, k iy is the coupling coefficient between the transmitting antenna, the resonator and the receiving antenna; ω is the resonant angular frequency, Q i They represent the quality factors at the transmitting end, resonator and receiving end respectively.

[0062] The receiving currents of the transmitting end, the resonator and the receiving end at a frequency of 13.56 MHz are respectively represented by I 1 ,I 2 ,I 3 Indicates; I 1 ,I 2 and I 3 The calculation formula is:

[0063]

[0064] Get the scattering parameters between the transmitter, resonator and receiver:

[0065]

[0066] Among them, S 31 is the scattering parameter between the transmitting antenna and the receiving antenna, S 21 is the scattering parameter between the transmitting antenna and the resonator, S 32 is the scattering parameter between the resonator and the receiving antenna;

[0067] The capacitors and resistors in the matching network form an RLC resonant circuit with the HF antenna to achieve the highest efficiency transmission of all RF energy;

[0068] The energy transmitted from the client to the HF chip is finally collected by the energy transmission efficiency:

[0069]

[0070] The HF antenna is a loop antenna, and nanosilver ink is printed on a flexible PET substrate by inkjet printing technology. When it works at a frequency of 13.56 MHz, the antenna size is 40 mm × 30 mm × 0.01 mm, and the antenna spacing is 0.5 mm.

[0071] The HF chip specifically uses the ISO14443 protocol to convert the collected energy into direct current through a rectifier circuit and a boost circuit, and then boosts the voltage and stores it in a supercapacitor;

[0072] Preferably, the data processing and control module includes a microcontroller, a signal amplifier and an AD converter;

[0073] The microcontroller is connected to the radio frequency information transmission module and the multi-parameter sensing module respectively. The microcontroller is used to receive information from the radio frequency information transmission module, send instructions to the multi-parameter sensing module, and transmit the sensing information collected by the multi-parameter sensing module to the signal amplifier; the signal amplifier is used to amplify and filter the information; the AD converter is used to convert the amplified and filtered sensing information, and transmit the converted information to the client through the radio frequency information transmission module.

[0074] In this embodiment, the rectifier circuit uses a Schottky diode to construct a bridge rectifier, and capacitor filtering is used to achieve the conversion of radio frequency energy into direct current, wherein the Schottky diode is HSMS-2855; the boost module (BQ25570) performs boost processing through a voltage manager (MAX6433) and stores the collected energy in a supercapacitor;

[0075] The data processing and control module establishes a connection with the radio frequency module and the sensor module through SPI serial communication, including a microcontroller, a signal amplifier and an AD converter. In this example, the microcontroller selects an MSP430 ultra-low power controller, whose operating voltage is 1.8-3.6V and the operating current is about 0.1μA. It establishes a connection with the radio frequency information transmission module and the multi-parameter sensor module through SPI serial communication, sends instructions to the sensor module after receiving information from the radio frequency information transmission module, and amplifies, filters (signal amplifier LM358DR), and AD converts (AD converter (AD5593R) the sensor information collected by the sensor module and transmits it back to the client through the radio frequency information transmission module.

[0076] In this embodiment, the specific preparation process of the radio frequency information transmission module, the data processing and control module and the radio frequency energy collection submodule includes: using nano silver ink to print the interconnection circuit and NFC antenna of the first layer by inkjet printing and curing them in an electric constant temperature drying oven at 100°C for 45 minutes, wherein the antenna is printed twice and the circuit wire is printed 3 times; using a dispensing method to cover the position where the first layer needs to be superimposed with insulating ink with a thickness of 100 μm, curing it with 365nm UV light and then curing it in an electric constant temperature drying oven at 80°C for 30 minutes; printing and preparing the designed interconnection wire on the insulating layer, The printing process requires that the two layers be aligned so that the parts of the two layers that need to be connected are aligned; according to the size design and packaging requirements of each electronic component, conductive silver glue is screen-printed where the chip needs to be welded, and the chip is aligned and placed in the corresponding position so that its lead angle is aligned with the wire. The conductive silver glue is welded to the prepared interconnection wire by heating and reflowing at 80°C and then cooled to room temperature. Finally, the surrounding is covered and cured at room temperature for 30 minutes to enhance the connection between the chip and the wire to achieve interconnection between components and integrated circuits; the PDMS film is attached to the integrated circuit as a packaging layer and cured at 60 degrees for about 1 hour;

[0077] Preferably, the multi-parameter sensing module includes a temperature sensor, a humidity sensor, an ammonia sensor and a pressure sensor.

[0078] Specifically, the sensor module in this embodiment collects environmental information and feeds the environmental information back to the client through the data processing and control module and the radio frequency information transmission module, including but not limited to temperature sensors, humidity sensors, ammonia sensors and pressure sensors;

[0079] In this example, it is specifically a temperature sensor, a humidity sensor and an ammonia sensor, all of which are printed on a flexible PET substrate by flexible printing technology. First, the designed sensing electrode is printed on a flexible PET film by inkjet printing technology and sintered at 120°C for 30 minutes. Then, each sensitive indicator sensing layer is scraped on the flexible electrode and sintered at 120°C for 60 minutes. Finally, the SPI serial communication technology is used to achieve interconnection with the data processing and control module. It has high precision, anti-bending and other good physical and chemical properties, and meets the complex and changeable transportation environment of actual cold chain logistics such as low temperature and high humidity.

[0080] The RF information transmission module receives the monitoring instructions transmitted by the client through RF transmission technology and collects the RF energy therein for use by the RF information transmission module, and while ensuring its own power supply, it stores the excess energy in the supercapacitor to reduce the charging time and ensure the normal operation of the environmental monitoring device. In this embodiment, the selected UHF chip is SL900A, which works at a frequency of 920MHz and uses the ISO15693 protocol to avoid frequency crosstalk with the HF chip;

[0081] Preferably, in order to maximize the utilization of energy collection efficiency, the data processing and control module controls the entire monitoring device to have three working states: working mode, transmission mode and sleep mode. When the multi-parameter monitoring module is awakened by the data processing and control module for data collection and transmission, it is in the working state. At this time, all modules are in the normal working mode, and its working current is about 20mA / ms; when the radio frequency transmission module is controlled by the data processing and control module to interact with the client through backscattering, it is in the transmission mode. At this time, the multi-parameter monitoring module is turned off, and only the information communication function between the data processing and control module and the radio frequency transmission module is retained. Its working current is about 14mA / ms; finally, when it is in an inactive state, it is in a low-power sleep state, and all modules only retain basic functions such as timers, and their working current is about 3mA / ms. Among them, the energy collection module is not affected by the working state. It notifies the data processing and control module through the voltage monitor and provides the energy information basis for the data processing and control module to determine which working state. When the monitored voltage value is lower than the highest threshold voltage, energy collection continues. When the monitored voltage value reaches the highest threshold voltage, the energy collection module is turned off.

[0082] Preferably, the client includes an NFC communication module, an RFID reader / writer, a control center, a user interaction module and a display module;

[0083] The NFC communication module is used to send energy collection information to the energy collection module; the RFID reader is used to issue data collection instructions to the radio frequency information transmission module and transmit them to the data processing and control module; the control center, the user interaction module and the display module are used to perform real-time interaction and visual display based on the sensed information, and feed back abnormal data to the user.

[0084] This embodiment also provides a flexible environmental monitoring method integrating multi-frequency antenna and energy harvesting, which is applied to the above agricultural product environmental monitoring device. The overall process is as follows: Figure 3 As shown, the method includes:

[0085] First, the NFC communication module of the client is used to send an energy collection signal to the RF energy collection module. The HF antenna improves the energy collection efficiency through the resonator. The impedance matching network of the HF chip and the HF antenna improves the energy collection efficiency for a second time. The collected RF energy is converted into direct current through the rectifier circuit and the weak direct current is amplified through the boost circuit to achieve boost processing and store the collected energy in the supercapacitor. The light detection module detects whether there is light that satisfies the solar sensor layer to collect light energy. When the conditions are met, energy conversion is performed and the collected energy is stored in the supercapacitor.

[0086] The voltage monitor is used to monitor the energy collected by the supercapacitor. When the voltage in the supercapacitor reaches the working voltage of the data processing and control module, the data processing and control module is turned on and communicates with the client through the radio frequency information transmission module. The client sends a data collection instruction to the radio frequency communication module through the RFID reader and transmits it to the data processing and control module. When the voltage in the supercapacitor reaches the working voltage of the sensor, the data processing and control module sends an environmental monitoring instruction to the multi-parameter sensor module and amplifies, filters and AD converts the data information collected by the multi-parameter sensor module and feeds it back to the client display module through the radio frequency information transmission module for real-time display and sends abnormal information to the user interaction module to remind the user.

[0087] After the data transmission is completed, the multi-parameter sensing module, the data processing and control module and the radio frequency information transmission module are turned off in sequence. At the same time, the voltage monitor continues to monitor the supercapacitor voltage. When the voltage reaches the highest threshold voltage, charging is stopped and the next environmental monitoring instruction is waited for. Otherwise, the capacitor voltage is monitored to see if it reaches the working voltage of the sensing module. When the capacitor voltage reaches the working voltage of the sensing module, charging is continued and the next environmental monitoring instruction is waited for. Otherwise, the capacitor voltage is monitored to see if it reaches the working voltage of the data processing and control module. When the capacitor voltage reaches the working voltage of the data processing and control module, charging is continued and the data processing and control module is turned on to wait for the next environmental monitoring instruction. Otherwise, the capacitor voltage is monitored to see if it reaches the lowest threshold voltage. When the capacitor voltage reaches the lowest threshold voltage, charging is continued and the data processing and control module is turned on.

[0088] The beneficial effects of the present invention are as follows:

[0089] The present invention improves the energy collection and transmission efficiency, reduces the charging time, and maximizes the utilization of the collected energy through an improved energy collection module. At the same time, the integrated multi-frequency antenna avoids crosstalk between antennas and ensures the correct transmission of information. Through the radio frequency information detection instruction sent by the client, the data processing and control module drives the sensor module to collect information when the energy collection module is normally powered and feeds back real-time environmental information to the client through the radio frequency information transmission module, ultimately ensuring the normal and smooth operation of the cold chain process.

[0090] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the method disclosed in the embodiment, since it corresponds to the device disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the device part description.

[0091] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A flexible environment monitoring device integrating multi-frequency antenna and energy harvesting, characterized in that: include: Energy collection module, multi-parameter sensing module, radio frequency information transmission module, data processing and control module and client; The energy collection module, the multi-parameter sensing module, the radio frequency information transmission module and the data processing and control module are all printed on a flexible PET substrate by flexible printing technology; The energy collection module is used to collect natural energy and / or radio frequency energy and store and supply power; the radio frequency energy is converted by the HF chip in the energy collection module to realize the collection of the radio frequency energy; the multi-parameter sensing module is used to collect environmental data in real time and transmit it to the data processing and control module for subsequent data processing, analysis, transmission and display; the data processing and control module is used to process the environmental data and control the normal operation of the entire environmental monitoring device; the radio frequency information transmission module is used to realize the real-time interconnection between the client and the sensor monitoring device, and send the processed data to the client; the client is used to send a collection signal instruction to the data processing and control module through the radio frequency information transmission module, send the radio frequency energy to the energy collection module, and control the working status of the data processing and control module and the multi-parameter sensing module, and also display the environmental information in real time according to the processed data, and notify the management personnel to carry out early warning and regulation when the environmental information is abnormal; The energy collection module includes a solar energy collection submodule and a radio frequency energy collection submodule; The radio frequency energy collection submodule includes a resonator, an HF antenna, an impedance matching network, an HF chip, a rectifier and filter circuit, a boost circuit, a super capacitor and a voltage monitor connected in sequence; The transmission efficiency of the RF energy collection submodule collecting energy emitted from the client to the HF chip is: Among them, S 31 is the scattering parameter between the transmitting antenna and the receiving antenna, S 21 is the scattering parameter between the transmitting antenna and the resonator, S 32 is the scattering parameter between the resonator and the receiving antenna; η is the energy transfer efficiency; S 31 , S 21 and S 32 Obtained through the following model: Wherein, I2 and I3 represent the receiving current of the resonator and the receiving end at a frequency of 13.56 MHz respectively; the calculation formulas of I2 and I3 are: Among them, M 12 、M 13 、M 23 They are the mutual inductance between the transmitting antenna and the resonator, the mutual inductance between the transmitting antenna and the receiving antenna, and the mutual inductance between the resonator and the receiving antenna: Among them, k iy is the coupling coefficient between the transmitting antenna, the resonator and the receiving antenna; ω is the resonant angular frequency, Q i Represents the quality factor at the transmitter, resonator and receiver, L i They represent the equivalent self-inductance changes of the transmitting antenna, resonator and receiving antenna, respectively, and Z i Indicates the impedance changes, specifically: Among them, R S is the resistance of the transmitting antenna power supply terminal, R Tx is the equivalent resistance of the transmitting antenna, R R is the resonator equivalent resistance, R L is the receiving end load resistance, R RX is the equivalent resistance of the receiving antenna, X i is the reactance change of the transmitting antenna, resonator and receiving antenna; V s is the source voltage at the transmitting end; The capacitor and resistor in the matching network form an RLC resonant circuit with the HF antenna; The radio frequency information transmission module receives the monitoring instructions transmitted by the client through radio frequency transmission technology and collects radio frequency energy in the client for use by the radio frequency information transmission module. The radio frequency information transmission module stores excess energy in the supercapacitor while ensuring its own power supply; The data processing and control module controls the entire monitoring device to have three working states: working mode, transmission mode and sleep mode.

2. The flexible environment monitoring device integrating multi-frequency antenna and energy harvesting according to claim 1, characterized in that: The solar energy collection submodule includes a light detector, a solar cell, a super capacitor and a voltage monitor connected in sequence; the light detector is used to detect whether there is light that satisfies the solar energy sensing layer to collect light energy, and if so, sends a collection signal to the solar cell; the solar cell is used to convert the collected light energy into electrical energy and store it; The supercapacitor is used to store the electrical energy; The voltage monitor is used to monitor the voltage state of the supercapacitor and adjust the working states of other modules according to the information obtained from the monitoring.

3. The flexible environment monitoring device integrating multi-frequency antenna and energy harvesting according to claim 1, characterized in that: The RF energy collection submodule is used to collect RF energy through RF energy collection technology when the illumination does not meet the solar sensing layer's illumination energy collection, causing the voltage monitor to monitor the supercapacitor voltage and fail to meet the sensor's operating voltage, and convert and process the RF energy and store it in the supercapacitor.

4. The flexible environment monitoring device integrating multi-frequency antenna and energy harvesting according to claim 1, characterized in that: The data processing and control module includes a microcontroller, a signal amplifier and an AD converter; The microcontroller is used to receive information from the radio frequency information transmission module, send sensing instructions to the multi-parameter sensing module, and transmit the sensing information collected by the multi-parameter sensing module to the signal amplifier; the signal amplifier is used to amplify and filter the information; the AD converter is used to convert the amplified and filtered sensing information, and transmit the converted information to the client through the radio frequency information transmission module.

5. The flexible environment monitoring device integrating multi-frequency antenna and energy harvesting according to claim 1, characterized in that: The multi-parameter sensing module includes a temperature sensor, a humidity sensor, an ammonia sensor and a pressure sensor.

6. The flexible environment monitoring device integrating multi-frequency antenna and energy harvesting according to claim 5, characterized in that: The method of printing the multi-parameter sensing module, the radio frequency information transmission module, the data processing and control module and the energy collection module into the flexible PET substrate is: Printing the sensing electrodes of the temperature sensor, the humidity sensor, the ammonia sensor and the pressure sensor on the flexible PET substrate by inkjet printing technology, and sintering at 120° C. for 30 min; The sensitive indicator sensing layers are scraped onto the flexible electrode and sintered at 120°C for 60 minutes. The first layer of interconnection circuits and NFC antennas were printed using inkjet printing and cured in an electric constant temperature drying oven at 100°C for 45 minutes, with the antenna printed twice and the circuit conductors printed three times; The insulating ink with a thickness of 100 μm is applied to the position where the first layer needs to be superimposed by the dispensing method, and then cured by 365 nm UV light and then cured in an electric constant temperature drying oven at 80°C for 30 min; Print the designed interconnection wires on the insulating layer, and according to the size design and packaging requirements of each electronic component, place the chip in the corresponding position and solder the screen-printed conductive silver glue on the prepared interconnection wires by heating and reflowing at 80°C, then cool to room temperature, and then cure at room temperature for 30 minutes; The PDMS film was attached to the integrated circuit as an encapsulation layer and cured at 60 degrees for 1 hour.

7. The flexible environment monitoring device integrating multi-frequency antenna and energy harvesting according to claim 1, characterized in that: The client includes an NFC communication module, an RFID reader / writer, a control center, a user interaction module and a display module; The NFC communication module is used to send energy collection information to the energy collection module; the RFID reader is used to issue data collection instructions to the radio frequency information transmission module and transmit them to the data processing and control module; the control center, the user interaction module and the display module are used to perform real-time interaction and visual display based on the sensed information, and feed back abnormal data to the user.

8. The flexible environment monitoring device integrating multi-frequency antenna and energy harvesting according to claim 1, characterized in that: When the multi-parameter sensing module is awakened by the data processing and control module for data collection and transmission, it is in working state. At this time, all modules are in normal working mode, and the working current is 20mA / ms; When the RF transmission module is controlled by the data processing and control module to exchange information with the client through backscattering, it is in the transmission mode. At this time, the multi-parameter monitoring module is turned off, and only the information communication function between the data processing and control module and the RF transmission module is retained. The working current is 14mA / ms; When in an inactive state, it is in a low-power sleep state, all modules only retain basic functions, and the working current is 3mA / ms; among them, the energy collection module is not affected by the working state, and it is controlled by the data processing and control module through the voltage monitor. When the monitored voltage value reaches the overload voltage, it keeps working to collect energy. When the maximum threshold voltage is reached, the energy collection module is turned off, and when the monitored voltage value is lower than the working voltage of the sensor module, it is reopened and continues to collect energy.

9. A flexible environment monitoring method integrating multi-frequency antenna and energy harvesting, applied to a flexible environment monitoring device integrating multi-frequency antenna and energy harvesting as claimed in any one of claims 1 to 8, characterized in that: The method comprises: The NFC communication module of the client is used to send an energy collection signal to the RF energy collection module. The HF antenna improves the energy collection efficiency through the resonator. The HF chip and the HF antenna improve the energy collection efficiency again through the impedance matching network. The collected RF energy is converted into direct current through the rectifier circuit and the weak direct current is amplified through the boost circuit to achieve boost processing and store the collected energy in the supercapacitor. At the same time, the light detection module detects whether there is light to meet the solar energy sensing layer to collect light energy. When the conditions are met, energy conversion is performed and the collected solar energy is stored in the supercapacitor. The energy collected by the supercapacitor is monitored by a voltage monitor. When the voltage in the supercapacitor reaches the working voltage of the data processing and control module, the data processing and control module is turned on and communicates with the client through the radio frequency information transmission module. The client sends a data collection instruction to the radio frequency communication module through the RFID reader and transmits it to the data processing and control module. When the voltage in the supercapacitor reaches the working voltage of the sensor, the data processing and control module sends an environmental monitoring instruction to the multi-parameter sensing module and amplifies, filters and performs AD conversion on the data information collected by the multi-parameter sensing module and feeds it back to the client display module through the radio frequency information transmission module for real-time display and sends abnormal information to the user interaction module to remind the user. After the data transmission is completed, the multi-parameter sensing module, the data processing and control module and the radio frequency information transmission module are closed in sequence. At the same time, the voltage monitor continues to monitor the supercapacitor voltage. When the voltage reaches the highest threshold voltage, charging is stopped and the next environmental monitoring instruction is waited for. Otherwise, the capacitor voltage is monitored to see if it reaches the working voltage of the sensing module. When the capacitor voltage reaches the working voltage of the sensing module, charging is continued and the next environmental monitoring instruction is waited for. Otherwise, the capacitor voltage is monitored to see if it reaches the working voltage of the data processing and control module. When the capacitor voltage reaches the working voltage of the data processing and control module, charging is continued and the data processing and control module is turned on to wait for the next environmental monitoring instruction. Otherwise, the capacitor voltage is monitored to see if it reaches the lowest threshold voltage. When the capacitor voltage reaches the lowest threshold voltage, charging is continued and the data processing and control module is turned on.

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