Internet of Things terminal devices based on visible light transmission of information and energy

Abstract

The present invention relates to the field of Internet of Things technology, and discloses an Internet of Things terminal device based on visible light transmission of information and energy. The device comprises a receiving module, an energy output submodule, and an information output submodule. The receiving module receives a visible light beam and converts it into electrical energy and electrical information, inputting the electrical energy into the energy output submodule and inputting the electrical information into the information output submodule. The energy output submodule comprises an energy input unit, an energy management chip, an energy storage unit, and an energy output unit. The energy management chip stores the electrical energy in the energy storage unit and manages the electrical energy to supply power to the device itself and an external load. The energy input unit includes a backup power supply connected to the energy management chip, which supplies power to the device itself and an external load when electrical energy is insufficient. The information output submodule processes the electrical information and outputs it. The present invention can achieve distortion-free signal transmission, efficient energy utilization, and stable and continuous power supply.

Description

Technical Field

[0001] The present invention relates to the technical field of Internet of Things, and in particular to an Internet of Things terminal device based on visible light transmission of information and energy. Background Art

[0002] With the development of fifth-generation mobile communication network technology, the Internet of Things (IoT) has gradually permeated every aspect of our lives. In addition to controlling and transmitting information about these IoT devices, effectively powering mobile IoT devices has become a key technology in this new generation of wireless communications. Visible light information and energy transmission technology uses visible light as a carrier for data transmission. Compared to traditional radio frequency communication technologies, it offers advantages such as abundant spectrum resources, low susceptibility to electromagnetic interference, and low cost. Furthermore, this technology can also use visible light as an energy carrier to power mobile IoT devices. Therefore, visible light information and energy transmission technology holds broad application prospects in the field of IoT terminals.

[0003] Researchers are increasingly in-depth in the technology and systems for synchronous transmission of visible light information and energy. Currently, the receiving end of IoT systems using synchronous visible light information and energy transmission typically utilizes a DC-DC boost circuit to maximize the transmission power of energy storage and photoelectric conversion devices. However, this technical solution introduces high-frequency noise, which interferes with the target signal being transmitted. Furthermore, currently available IoT systems using synchronous visible light information and energy transmission also suffer from the inability to maintain self-power. Summary of the Invention

[0004] To this end, the technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide an Internet of Things terminal device based on visible light transmission of information and energy, so as to achieve distortion-free transmission of signals, efficient utilization of energy and stable and continuous wireless power supply.

[0005] To solve the above technical problems, the present invention provides an Internet of Things terminal device based on visible light transmission of information and energy, comprising a receiving module and an output module, wherein the output module comprises an energy output submodule and an information output submodule, wherein the energy output submodule comprises an energy input unit, an energy management chip, an energy storage unit and an energy output unit, wherein the energy input unit comprises a backup power supply;

[0006] The receiving module receives the visible light beam and converts it into electrical energy and electrical information, and the receiving module inputs the electrical energy into the energy output submodule through the energy input unit;

[0007] The energy management chip is respectively connected to the energy input unit, the energy storage unit, the energy output unit and the backup power supply. The energy management chip stores the electric energy in the energy storage unit, manages the electric energy and supplies power to the device itself and the external load through the energy output unit. When the electric energy is insufficient, the energy management chip manages the backup power supply to supply power to the device itself and the external load.

[0008] The receiving module is connected to the information output submodule. The receiving module inputs the electrical information into the information output submodule, and the information output submodule processes the electrical information and outputs it.

[0009] Preferably, the receiving module includes an optical antenna, a photoelectric conversion device and an information and energy separation circuit, the output end of the optical antenna is connected to the input end of the photoelectric conversion device, and the output end of the photoelectric conversion device is connected to the input end of the information and energy separation circuit;

[0010] The information and energy separation circuit includes an information transmission branch and an energy transmission branch connected in parallel, the output end of the information transmission branch is connected to the information output submodule, and the output end of the energy transmission branch is connected to the energy output submodule;

[0011] The optical antenna collects the visible light beam and inputs it into the photoelectric conversion device, and the photoelectric conversion device converts the collected visible light beam into electrical energy and electrical information and inputs it into the information and energy separation circuit;

[0012] The information and energy separation circuit separates the electrical energy and electrical information, inputs the electrical information into the information output submodule through the information transmission branch, and inputs the electrical energy into the energy output submodule through the energy transmission branch.

[0013] Preferably, the energy storage unit includes a third capacitor, a fourth capacitor and a second diode, the capacitance value of the third capacitor is smaller than the capacitance value of the fourth capacitor, the positive poles of the third capacitor and the fourth capacitor are respectively connected to the energy management chip, the negative poles of the third capacitor and the fourth capacitor are both grounded, the positive pole of the second diode is connected to the positive pole of the fourth capacitor, and the negative pole of the second diode is connected to the positive pole of the third capacitor.

[0014] Preferably, the energy output submodule further includes a first threshold setting unit and a second threshold setting unit, and the first threshold setting unit and the second threshold setting unit are respectively connected to the energy management chip;

[0015] The energy management chip has a built-in low-voltage dropout linear regulator, and the energy output unit includes an energy output submodule threshold output port, an energy output submodule output port, and a low-voltage dropout linear regulator output port connected to the energy management chip; the energy management chip supplies power to the external load through the energy output submodule output port, and the energy management chip supplies power to the information output submodule through the energy output submodule threshold output port and the low-voltage dropout linear regulator output port;

[0016] The first threshold setting unit adjusts the output voltage range of the energy output submodule threshold output port and the energy output submodule output port through the energy management chip, and the second threshold setting unit adjusts the output voltage size of the low voltage difference linear regulator output port through the energy management chip.

[0017] Preferably, the first threshold setting unit includes a first resistor, a second resistor and a third resistor, both ends of the first resistor and the second resistor are connected to the energy management chip, and both ends of the third resistor are connected to the energy management chip and the ground wire respectively;

[0018] The second threshold setting unit includes a fourth resistor, a fifth resistor and a sixth capacitor, both ends of the fourth resistor are connected to the energy management chip, both ends of the fifth resistor are respectively connected to the energy management chip and the ground line, and both ends of the sixth capacitor are respectively connected to the two ends of the fourth resistor.

[0019] Preferably, the information output submodule includes a preamplifier unit, a filtering and amplifying unit, a shaping unit and an information output submodule output port, the output end of the preamplifier unit is connected to the input end of the filtering and amplifying unit, the output end of the filtering and amplifying unit is connected to the input end of the shaping unit, the output end of the shaping unit is connected to the output port of the information output submodule, and the information output submodule outputs an electrical signal through the information output submodule output port.

[0020] Preferably, the information output submodule further includes a reference unit, and the reference unit includes a zeroth operational amplifier, a ninth resistor, a tenth resistor, a sixteenth capacitor, and a seventeenth capacitor;

[0021] One end of the tenth resistor is grounded, and the other end of the tenth resistor is connected to the non-inverting input terminal of the zeroth operational amplifier; one end of the ninth resistor is connected to the non-inverting input terminal of the zeroth operational amplifier, and the other end of the ninth resistor is connected to the energy management chip; one end of the sixteenth capacitor and the seventeenth capacitor connected in parallel is grounded, and the other end of the sixteenth capacitor and the seventeenth capacitor connected in parallel is connected to the energy management chip;

[0022] The reference unit is connected to the preamplifier unit, the filter amplifier unit, and the shaping unit respectively, and provides a stable reference voltage for the preamplifier unit, the filter amplifier unit, and the shaping unit.

[0023] Preferably, the preamplifier unit includes a transimpedance amplifier and a reference voltage input port, the transimpedance amplifier includes a first operational amplifier chip, the non-inverting end of the first operational amplifier chip is provided with the reference voltage input port, and when the reference voltage output by the reference unit is input into the non-inverting end of the first operational amplifier chip, the output voltage of the transimpedance amplifier is raised by a reference through the reference voltage input port.

[0024] Preferably, the filtering and amplifying unit includes a second operational amplifier, an eleventh capacitor, a seventh resistor, and an eighth resistor, wherein the eleventh capacitor and the eighth resistor are connected in parallel to form a low-pass filter; the seventh resistor is connected to the inverting input terminal of the second operational amplifier, and the seventh resistor, the eighth resistor, and the second operational amplifier form an inverting amplifier;

[0025] The shaping unit includes a comparator, a non-phase port of the comparator is connected to the output port of the filtering and amplifying unit, and an inverting port of the comparator is connected to the output port of the reference unit.

[0026] Preferably, the output of the energy output submodule includes a first output, a second output and a third output.

[0027] The first output is the energy management chip supplying power to the preamplifier unit and the filter amplifier unit through the threshold output port of the energy output submodule.

[0028] The second output includes a first sub-path and a second sub-path, the first sub-path is for the energy management chip to supply power to an external load through the output port of the energy output sub-module, and the second sub-path is for the energy management chip to supply power to the built-in low voltage drop linear regulator;

[0029] The third output is that the energy management chip supplies power to the reference unit and the shaping unit through the output port of the low voltage difference linear regulator.

[0030] The above technical solution of the present invention has the following advantages over the prior art:

[0031] The present invention realizes energy collection and management through the cooperation of the energy management chip, the energy output submodule and the information output submodule without the need for external auxiliary signals, and thus does not interfere with the target information, and has the advantage of low noise; at the same time, the present invention realizes continuous power supply to the device itself and efficient use of energy by arranging a backup power supply in the energy input unit and an energy storage unit in the energy output submodule, greatly improving the endurance of the Internet of Things terminal equipment, and has the advantages of wireless communication, safety, speed and high endurance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0033] Figure 1 Schematic diagram of the working block diagram of an embodiment of the present invention,

[0034] Figure 2 FIG. 1 is a schematic diagram showing the connection between the photoelectric conversion device and the information and energy separation circuit in an embodiment of the present invention.

[0035] Figure 3 is a circuit design diagram of the energy output submodule in an embodiment of the present invention,

[0036] Figure 4 is a circuit design diagram of a reference unit in an embodiment of the present invention,

[0037] Figure 5 This is a circuit design diagram of the information output submodule in an embodiment of the present invention.

[0038] Figure 6 Schematic diagram of the overall structure of an embodiment of the present invention.

[0039] Explanation of the markings in the figure in the specification: 1. Optical antenna; 2. Photoelectric conversion device; 3. Information and energy separation circuit; 4-1. First threshold setting unit; 4-2. Second threshold setting unit; 5. Energy input unit; 6. Energy management chip; 7. Energy storage unit; 8. Energy output unit; 9. Energy output submodule output port; 10. Preamplifier unit; 11. Filter amplification unit; 12. Shaping unit; 13. Information output submodule output port; 14. Reference unit; 15. Information and energy separation circuit input port; 16. Information transmission branch output port; 17. Energy transmission branch output port; 18. Energy output submodule input port; 19. Energy output submodule threshold output port; 20. Low voltage difference linear regulator output port; 21. Reference unit output port; 22. Low-pass filter; 23. Filter amplification unit output port. DETAILED DESCRIPTION

[0040] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0041] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Therefore, features specified as "second" or "first" may explicitly or implicitly include one or more of such features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined. The term "connected" should be understood broadly, for example, to mean fixed, removable, or integral; mechanical, electrical, or communicative; direct or indirect through an intermediary; internal connectivity between two elements or interaction between two elements. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances. The term "comprising" is intended to cover non-exclusive inclusion, such as a process, method, system, product, or apparatus that includes a series of steps or units, is not limited to the listed steps or units, and may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0042] like Figure 1 As shown, the present invention discloses an Internet of Things terminal device capable of realizing synchronous transmission of visible light information and energy, comprising a receiving module and an output module, wherein the output module comprises an energy output submodule and an information output submodule; the receiving module receives a visible light beam and converts it into electrical energy and electrical information, inputs the electrical energy into the energy output submodule, and inputs the electrical information into the information output submodule; the energy output submodule comprises an energy input unit 5, an energy management chip 6, a first threshold setting unit 4-1, a second threshold setting unit 4-2, an energy storage unit 7, and an energy output unit 8, wherein the energy management chip 6 stores the electrical energy in the energy storage unit 7. The energy storage unit 7 manages the electrical energy through the energy management chip 6 and transmits the electrical energy to the energy output unit 8, and the energy output unit 8 supplies part of the electrical energy to an external load (such as a microprocessor, a sensor, etc.) through the energy output submodule output port 9 (that is, the energy output submodule output port 9 is only used for external power supply, not for powering the device itself); at the same time, the energy output unit 8 also simultaneously supplies part of the electrical energy through the energy output submodule threshold output port 19 (see Figure 3 ) and the low dropout linear regulator output port 20 (see Figure 3) to power the device itself. The energy management chip 6 has a built-in low-dropout linear regulator (LDO) with independent input and output to provide a stable voltage. The energy input unit 5 includes a backup power supply, which is connected to the energy management chip 6. When the power is insufficient, the energy management chip 6 uses the backup power supply to power the device itself and the external load. In this embodiment, the backup power supply is a battery. The information output submodule processes the electrical information and outputs it.

[0043] like Figure 3 As shown, the energy output submodule also includes an energy input unit 5, which includes a backup battery and an energy output submodule input terminal 18. The electric energy input through the energy transfer branch is input into the energy output submodule through the energy input unit 5. The energy input unit 5 inputs the electric energy into the energy management chip 6. The backup battery is connected to the energy management chip 6. When the electric energy is insufficient, the energy management chip 6 supplies power to the device itself and the external load through the backup battery. The electric energy is input into the energy output submodule through the energy output submodule input terminal 18 in the energy input unit 5. The energy storage unit 7 adopts a two-stage capacitor storage method, which can achieve stable power supply under good lighting conditions. Under no lighting conditions (or weak lighting conditions), it can cooperate with the backup battery to power the device itself and the external load, thereby achieving continuous power supply.

[0044] The receiving module includes an optical antenna 1, a photoelectric conversion device 2 and an information and energy separation circuit 3, the output end of the optical antenna 1 is connected to the input end of the photoelectric conversion device 2, and the output end of the photoelectric conversion device 2 is connected to the input end 15 of the information and energy separation circuit; the information and energy separation circuit 3 includes a parallel information transmission branch and an energy transmission branch, the output end of the information transmission branch is connected to the information output submodule, and the output end of the energy transmission branch is connected to the energy output submodule; the optical antenna 1 collects the visible light beam and inputs it into the photoelectric conversion device 2, and the photoelectric conversion device 2 converts the collected visible light beam into electrical energy and electrical information and inputs it into the information and energy separation circuit 3; the information and energy separation circuit 3 separates the electrical energy and electrical information, inputs the electrical information into the information output submodule through the information transmission branch, inputs the electrical energy into the energy output submodule through the energy transmission branch, and supplies power to the external load and the information output submodule when the voltage across the capacitor inside the energy storage unit 7 rises to a set threshold.

[0045] like Figure 2As shown, the information and energy separation circuit 3 is a decoupling circuit, which is composed of a capacitor (zero capacitor C0) and an inductor (zero inductor L0) connected in parallel. The output end of the photoelectric conversion device 2 is connected to the information and energy separation circuit input end 15, that is, the photocurrent generated by the photoelectric conversion device 2 is shunted and transmitted through the information transmission branch output port 16 and the energy transmission branch output port 17. Among them, the energy transmission branch includes the zero inductor L0, which is used for the transmission of DC signals. The zero inductor L0 can attenuate the AC signal, thereby eliminating the ripple of the DC signal. The information transmission branch includes the zero capacitor C0, which can block the DC signal while ensuring that most of the AC signal can be transmitted through the information transmission branch. The energy transmission branch is connected to the input end of the energy output submodule; the information transmission branch is connected to the input end of the information output submodule. The optical antenna 1 described in this embodiment is a concentrator, which has an excellent focusing effect on incident light in the visible light band. The photoelectric conversion device 2 is an amorphous silicon solar cell. Different types of solar cells can be selected based on the lighting conditions of the application scenario. For example, at room temperature of 25°C, for indoor lighting between 100 and 1000 lux, amorphous silicon solar cells have higher conversion efficiency than polycrystalline silicon and single crystal silicon structures, and have higher photoelectric conversion efficiency for visible light used for lighting, while also having lower production costs.

[0046] like Figure 3 As shown, the energy storage unit 7 includes a third capacitor C3, a fourth capacitor C4 and a second diode D2. The capacitance value of the third capacitor C3 is smaller than the capacitance value of the fourth capacitor C4. VSTORE1 and VSTORE2 are charging output pins of the energy management chip 6. The positive electrodes of the third capacitor C3 and the fourth capacitor C4 are respectively connected to the VSTORE1 and VSTORE2 pins of the energy management chip 6. The negative electrodes of the third capacitor C3 and the fourth capacitor C4 are both grounded. The positive electrode of the second diode D2 is connected to the positive electrode of the fourth capacitor C4, and the negative electrode of the second diode D2 is connected to the positive electrode of the third capacitor C3.

[0047] In this embodiment, the third capacitor C3 uses a supercapacitor of 100μF to 500μF, and the fourth capacitor C4 uses a supercapacitor of 10mF to 500mF. When the voltage across the third capacitor C3 reaches the upper charging limit voltage, charging stops, and the third capacitor C3 begins to discharge. During the discharge process of the third capacitor, the fourth capacitor C4 begins to charge. When the voltage across the third capacitor C3 drops to the lower discharge limit voltage, discharging stops and charging begins again. When the voltage across the third capacitor C3 reaches the upper charging limit voltage, the third capacitor C3 begins to discharge again, and the fourth capacitor C4 begins to charge again. The above charging and discharging process is repeated until the voltage across the third capacitor C3 and the fourth capacitor C4 both reach the upper charging limit voltage. When the difference between the voltage across the fourth capacitor C4 and the voltage across the third capacitor C3 exceeds the voltage drop value of the second diode D2, the fourth capacitor C4 begins to charge the third capacitor C3. The function of the second diode D2 is to prevent current backflow that may occur when C4 charges C3. Currently, there are two main types of energy storage components suitable for light energy harvesting circuits: lithium batteries and supercapacitors. Supercapacitors outperform lithium batteries in terms of charge and discharge speed and cycle life. They can collect energy from the environment more quickly, and their longer cycle life facilitates future maintenance. Supercapacitors also offer more stable operating characteristics, and their charge and discharge circuits are simpler. Therefore, 100μF and 100mF supercapacitors can be used for C3 and C4, respectively.

[0048] The function of the energy management chip 6 is to control the energy distribution and energy output of the energy output submodule. Different chip models can be selected according to different usage requirements. In this embodiment, the energy management chip 6 uses the S6AE101A, S6AE102A or S6AE103A of CYPRESS. This series of chips has the characteristics of small size and ultra-low power consumption. It also has the advantage of saving energy while meeting the voltage requirements of different loads. Figure 3 The energy management chip 6 in the embodiment is an example of a chip of type S6AE102A. The energy management chip 6 needs to have a normal operation of the electric energy from the second capacitor C2 (see Figure 3 ), one end of the second capacitor C2 is connected to the VINT pin of the energy management chip 6, and the other end is grounded. In this embodiment, the value of the second capacitor C2 can be selected as 1μF. The current conventional technology uses a DC-DC boost circuit solution to solve the problem of energy storage and maximizing the power transmission of solar cells. This solution requires the introduction of a high-frequency signal, and the additionally introduced high-frequency signal will interfere with the target signal and affect the signal transmission effect. The present invention uses an energy management chip 6 to solve the problems of energy transmission, management, and storage. The circuit design of each unit inside and outside the energy management chip 6 does not introduce high-frequency signals. Therefore, unlike the traditional DC-DC boost circuit solution, the solution described in the present invention will not introduce high-frequency noise and will not interfere with the transmitted target signal.

[0049] The energy output submodule further includes a first threshold setting unit 4-1 and a second threshold setting unit 4-2, each of which is connected to the energy management chip 6. The energy output unit 8 includes an energy output submodule threshold output port 19, an energy output submodule output port 9, and a low-voltage dropout linear regulator output port 20, each of which is connected to the VOUT1, VOUT2, and VOUT-LDO pins of the energy management chip 6. The receiving module converts the electrical energy stored in the energy storage unit 7 and the electrical energy in the backup power supply. Under the control of the energy management chip 6, the receiving module supplies power to an external load through the energy output submodule output port 9 via the energy output unit 8, and supplies power to the information output submodule (i.e., the preamplifier unit 10, the filter amplifier unit 11, the reference unit 14, and the shaping unit 12) through the energy output submodule threshold output port 19 and the low-voltage dropout linear regulator output port 20.

[0050] The first threshold setting unit 4-1 adjusts the output voltage range of the energy output submodule threshold output port 19 and the energy output submodule output port 9 through the energy management chip 6. For example, for the optional S6AE102A chip of the present invention, its output voltage range is 1.1V to 5.2V. The second threshold setting unit 4-2 adjusts the output voltage of the low-dropout linear regulator output port 20 through the energy management chip 6. For the optional S6AE102A chip of the present invention, its output voltage can be adjusted within the range of 1.3V to 5V. In this embodiment, in response to the power supply requirements of the device, the voltage threshold range adjusted by the first threshold setting unit 4-1 is from a minimum output voltage of 2.7V to a maximum output voltage of 4V; the voltage value adjusted by the second threshold setting unit 4-2 is 3.3V.

[0051] The first threshold setting unit 4-1 includes a first resistor R1, a second resistor R2, and a third resistor R3. One end of each of the first resistor R1, the second resistor R2, and the third resistor R3 is connected to the SET-VOUTFB, SET-VOUTH, and SET-VOUTL pins of the energy management chip 6, respectively. The other end of the first resistor R1 is connected to the SET-VOUTH pin of the energy management chip 6. The other end of the second resistor R2 is connected to the SET-VOUTL pin of the energy management chip 6. The other end of the third resistor R3 is connected to ground. The second threshold setting unit 4-2 includes a fourth resistor R4, a fifth resistor R5, and a sixth capacitor C6. One end of each of the fourth resistor R4 and the fifth resistor R5 is connected to the VOUT-LDO and FB-LDO pins of the energy management chip 6, respectively. The other end of the fourth resistor R4 is connected to the FB-LDO pin of the energy management chip 6. The other end of the fifth resistor R5 is connected to ground. The two ends of the sixth capacitor C6 are connected to the two ends of the fourth resistor R4, respectively.

[0052] It should be pointed out that the energy management chip 6 has requirements for the voltage range of the photoelectric conversion device 2 input to the energy management chip 6 and the output voltage range of the energy output unit 8. The energy management chip 6 used in this embodiment requires an input voltage range of 2V to 5.5V and an output voltage range of 1.1V to 5.2V. Since continuous charging may cause overvoltage of the energy management chip 6 or undervoltage due to a sudden drop in ambient light energy during the light energy collection process, the energy management chip 6 needs to be provided with a VDD pin input overvoltage protection (OVP: Over Voltage Protection) function. When the VDD pin voltage of the energy management chip 6 exceeds the OVP detection voltage (i.e. 5.4V), an OVP protection current flows from the VDD pin to suppress the rise of the VDD pin voltage. In order to enhance the stability of the energy output submodule circuit, a first threshold setting unit 4-1 and a second threshold setting unit 4-2 are designed to avoid damage to the energy management chip 6 due to excessive output voltage. The minimum voltage and maximum voltage corresponding to the energy output submodule threshold output port 19 and the energy output submodule output port 9 are the same as Figure 3 The resistance values ​​of the first resistor R1, the second resistor R2, and the third resistor R3 in the first threshold setting unit 4-1 are related and satisfy the relationship of equations (1) and (2).

[0053] Voltage upper limit:

[0054] Voltage lower limit:

[0055] Wherein, a and b are adjustable coefficients. In this embodiment, a=57.5 and b=11.1.

[0056] The energy management chip 6 integrates a low voltage dropout linear regulator (LDO), which is used to output a stable voltage. The output voltage of the built-in low voltage dropout linear regulator output port 20 of the energy management chip 6 is the same as the output voltage of the LDO. Figure 3 The resistance values ​​of the fourth resistor R4 and the fifth resistor R5 of the second threshold setting unit 4-2 are related and satisfy the constraint of formula (3).

[0057]

[0058] Wherein c and d are adjustable coefficients. In this embodiment, c=1.15 and d=11.1.

[0059] In this embodiment, the sixth capacitor C6 in the second threshold setting unit 4-2, the fifth capacitor C5 in the energy output unit 8, and the seventh capacitor C7 are all bypass capacitors. C5, C6, and C7 can reduce the ripple of the output voltage. The values ​​of C5, C6, and C7 can be selected as 10μF, 220pF, and 1μF, respectively. The resistance values ​​of the first resistor R1, the second resistor R2, and the third resistor R3 in the first threshold setting unit 4-1 are 4MΩ, 4.4MΩ, and 9.1MΩ, respectively. The resistance values ​​of the fourth resistor R4 and the fifth resistor R5 in the second threshold setting unit are 6.8MΩ and 3.4MΩ, respectively. The corresponding VOUTH, VOUTL, and VLDO are 4V, 2.7V, and 3.3V, respectively.

[0060] The information output submodule includes a preamplifier unit 10, a filtering and amplifying unit 11, a shaping unit 12 and an information output submodule output port 13. The preamplifier unit 10 is connected to the information transmission branch, the output end of the preamplifier unit 10 is connected to the input end of the filtering and amplifying unit 11, the output end of the filtering and amplifying unit 11 is connected to the input end of the shaping unit 12, the output end of the shaping unit 12 is connected to the information output submodule output port 13, and the information output submodule outputs an electrical signal to the outside world through the information output submodule output port 13; the electrical information is input into the information output submodule through the preamplifier unit 10, the preamplifier unit 10 preamplifies the electrical signal, the filtering and amplifying unit 11 filters the electrical signal, and the shaping unit 12 amplifies and shapes the electrical signal and then outputs it through the information output submodule output port 13, thereby realizing preamplification, filtering, amplification and shaping processing of the electrical information.

[0061] like Figure 4As shown, the information output submodule further includes a reference unit 14, the reference unit 14 includes a low-power single-power supply zeroth operational amplifier A0 and a peripheral circuit, the peripheral circuit includes a ninth resistor R9, a tenth resistor R10, a sixteenth capacitor C16 and a seventeenth capacitor C17; one end of the tenth resistor R10 is grounded, and the other end of the tenth resistor R10 is connected to the non-inverting input terminal of the zeroth operational amplifier A0; one end of the ninth resistor R9 is connected to the non-inverting input terminal of the zeroth operational amplifier A0, and the other end of the ninth resistor R9 is connected to the The output port 20 of the built-in low-voltage dropout linear regulator of the energy management chip 6 is connected to the output port 20 of the low-voltage dropout linear regulator of the energy management chip 6; one end of the parallel connection of the sixteenth capacitor C16 and the seventeenth capacitor C17 is grounded, and the other end of the parallel connection of the sixteenth capacitor C16 and the seventeenth capacitor C17 is connected to the output port 20 of the built-in low-voltage dropout linear regulator of the energy management chip 6; the reference unit 14 is respectively connected to the preamplifier unit 10, the filter amplifier unit 11, and the shaping unit 12 to provide a stable reference voltage for the preamplifier unit 10, the filter amplifier unit 11, and the shaping unit 12. The output port 21 of the reference unit 14 outputs a low-impedance, stable reference voltage, which raises the voltage reference of the information output submodule and provides the necessary conditions for solving the phase reversal problem under single power supply conditions.

[0062] The zeroth operational amplifier A0 is used to form a voltage follower, whose input impedance is infinite and output impedance is infinitely small, which can better achieve signal coupling with the upper circuit and the lower circuit, and reduce the loss of the target signal. The built-in low-voltage difference linear regulator output port 20 of the energy management chip 6 is simultaneously connected to the positive power supply terminal and the non-phase input terminal of the zeroth operational amplifier A0 to provide energy to the zeroth operational amplifier A0. The inverting input terminal of the zeroth operational amplifier A0 is directly connected to the output port of the zeroth operational amplifier A0 to form a voltage follower. The size of the input signal Vi is determined by the ninth resistor R9 and the tenth resistor R10, that is, Based on the principle of a voltage follower, the output voltage VREF = Vi. The negative supply terminal of the zeroth operational amplifier A0 is grounded, and a single power supply is used. In this embodiment, R9 can be 1.8MΩ, R10 can be 1.5MΩ, VLDO is 3.3V, and VREF is 1.5V. C16 and C17 are bypass capacitors, with values ​​of 1μF and 100nF, respectively, to reduce power supply input ripple and ensure more stable power supply. The zeroth operational amplifier A0 can be a Texas Instruments TLV2401.

[0063] like Figure 5As shown, the preamplifier unit 10 includes a trans-impedance amplifier (TIA) and a reference voltage input port. The trans-impedance amplifier includes a low-power first operational amplifier chip A1, a sixth negative feedback resistor R6, and an eighth negative feedback capacitor C8. The function of the trans-impedance amplifier is to convert the photocurrent into a voltage signal to facilitate subsequent filtering and voltage amplification processing. The non-inverting terminal of the first operational amplifier chip A1 is provided with the reference voltage input port. When the reference voltage output by the reference unit 14 is input to the non-inverting terminal of the first operational amplifier chip A1, the output voltage of the trans-impedance amplifier is raised by a reference voltage through the reference voltage input port. In this embodiment, R6 can be selected to be 1kΩ, C8, C9, and C10 can be selected to be 220pF, 1μF, and 100nF, respectively. The first operational amplifier chip A1 can be selected to be the Texas Instruments OPA379.

[0064] The transimpedance amplifier operates from a single power supply (with the power supply port being the positive power input port), which further reduces power consumption and circuit design complexity. The current signal is converted into a voltage signal, with the current-to-voltage gain based on the size of the feedback resistor. Two filter capacitors (the ninth capacitor C9 and the tenth capacitor C10) are connected in parallel to the positive power input port to reduce input power ripple and ensure a more stable power supply. The input-output relationship of the preamplifier unit 10 can be expressed as: U0 = I × RF, where U0 is the output voltage, I is the input current, and RF is the sixth feedback resistor R6. The eighth feedback capacitor C8 is connected in parallel across the feedback resistor to prevent self-oscillation from affecting the circuit. The threshold output port 19 of the energy output submodule is connected to the positive power supply port of the first operational amplifier chip A1 to provide energy to the preamplifier unit 10. Because the signal is inputted in an inverted phase at the operational amplifier, the output signal's phase is flipped 180 degrees. Adding a reference voltage at this point can mitigate the adverse effects of signal inversion under single-power supply conditions.

[0065] like Figure 5As shown, the filter amplifier unit 11 is a low-pass inverting amplifier that filters high-frequency noise from the output voltage of the preamplifier unit 10 and performs secondary amplification. The low-pass inverting amplifier comprises a low-power, single-supply second operational amplifier A2 and peripheral circuitry. It filters high-frequency noise and performs secondary amplification on the valid signal. The peripheral circuitry includes an eleventh negative feedback capacitor C11, an eighth negative feedback resistor R8, and a seventh resistor R7. The eleventh negative feedback capacitor C11 and the eighth negative feedback resistor R8 are connected in parallel to form a low-pass filter 22. The seventh resistor R7 is connected to the inverting input of the second operational amplifier A2. Together with the seventh resistor R7 and the eighth negative feedback resistor R8, they form an inverting amplifier and determine the gain of the filter amplifier unit 11. Furthermore, the power supply method, reference voltage input port, and filter capacitor configuration for the positive power input port of the filter amplifier unit 11 are consistent with those of the preamplifier unit 10.

[0066] The threshold output port 19 of the energy output submodule is connected to the positive power supply terminal of the second operational amplifier A2 to power the filter amplifier unit 11. Here, the relationship between the input signal VI and the output signal VO is determined by the following formula: The cut-off frequency fp of the low-pass filter 22 is given by The negative power supply terminal of the second operational amplifier A2 is grounded, using a single power supply. The output port 21 of the reference unit 14 is connected to the non-inverting terminal of the second operational amplifier A2, so that the output signal of the operational amplifier is raised by a reference voltage. The functions and values ​​of C12 and C13 are the same as those of C9 and C10 in the preamplifier unit 10. In this embodiment, R7, R8, and C11 can be 1kΩ, 20kΩ, and 3.9nF, respectively, and the operational amplifier can be the Texas Instruments OPA379.

[0067] like Figure 5 As shown, the shaping unit 12 includes a threshold comparator, which includes a third operational amplifier A3, a fourteenth capacitor C14, and a fifteenth capacitor C15. A low-power comparator and two filter capacitors constitute a threshold comparator, and the filter capacitor setting is consistent with the preamplifier unit 10. The function of the shaping unit 12 is to output a binary voltage signal by comparing the voltage input to the comparator's positive and negative ports. The positive port of the threshold comparator is connected to the output port 23 of the filter amplifier unit 11, the negative port of the threshold comparator is connected to the output port of the reference unit 14, and the positive power input port of the threshold comparator A3 is connected to the third output port of the energy output unit 8.

[0068] The voltage signal from the shaping unit 12 is output from the output port 23 of the filtering and amplifying unit 11 and then transmitted to the non-inverting terminal of the operational amplifier A3, where it is compared with the voltage signal from the output port 21 of the reference unit 14. When the voltage signal output by the filtering and amplifying unit 11 is greater than the reference voltage output by the reference unit 14, the comparator output voltage matches the voltage at the positive power supply input port, indicating a high level; otherwise, the comparator outputs 0V, indicating a low level. This process can be understood as ultimately outputting a binary signal, either a high level or a low level, or as a one-bit analog-to-digital conversion process. This process ultimately ensures that the voltage signal output by the output port 13 of the information output submodule is compatible with the input voltage of a conventional microprocessor. Here, the output voltage VLDO of the low-dropout linear regulator output port 20 built into the energy management chip 6 is set to 3.3V, and the output voltage VREF of the output port 21 of the reference unit 14 is set to 1.5V. This means that the output port 13 of the information output submodule ultimately outputs a binary signal with a high level of 3.3V and a low level of 0V. In this embodiment, the functions and values ​​of C14 and C15 are the same as those of C9 and C10 in the preamplifier unit 10; the third operational amplifier A3 can be TLV7011 produced by Texas Instruments.

[0069] In this embodiment, the output of the energy output submodule is divided into three paths. The first output path is output through the energy output submodule threshold output port 19 in the energy output unit 8 (connected to the preamplifier unit 10 and the filter amplifier unit 11). The energy output submodule supplies power to the preamplifier unit 10 and the filter amplifier unit 11 through the first output path. The first threshold setting unit 4-1 adjusts the corresponding voltage range to VOUTL~VOUTH. The second output path of the energy output unit 8 includes a first sub-path and a second sub-path. The first sub-path is for the energy management chip 6 to supply power to the external load through the energy output submodule output port 9. The second sub-path is for the energy management chip 6 to supply power to the built-in low-dropout linear regulator, thereby providing power to the external load. The first threshold setting unit 4-1 adjusts the corresponding voltage range to VOUTL~VOUTH. The third output of the energy output unit 8 is connected to the shaping unit 12 and the reference unit 14 through the output port of the low voltage difference linear regulator to supply power to the shaping unit 12 and the reference unit 14; the corresponding voltage is a stable value and is adjusted to VLDO by the second threshold setting unit 4-2.

[0070] like Figure 6The figure shows the overall structure of an IoT terminal device capable of synchronous transmission of visible light information and energy. The optical antenna 1 is located above the photoelectric conversion device 2, and the information and energy separation circuit 3 is located below the photoelectric conversion device 2. From the primary viewing angle, the left half of the information and energy separation circuit 3 is the information output submodule, and the right half is the energy output submodule. The information output submodule includes a preamplifier unit 10, a filter amplifier unit 11, a shaping unit 12, and a reference unit 14. The reference unit 14 is located below the amplification and filtering module and provides a reference voltage for the preamplifier unit 10, filter amplifier unit 11, and shaping unit 12 of the information output submodule. The output port 13 of the information output submodule is located above the shaping unit 12 and outputs the target information signal to achieve communication. The right half of the information and energy separation circuit 3 is the energy output submodule, which includes, from left to right, the energy input unit 5, the energy management chip 6, and the energy storage unit 7. The first threshold setting unit 4-1 and the second threshold setting unit 4-2 (note that these two threshold setting units are combined and placed together) are located below the energy management chip 6; the output port 9 of the energy output submodule is located above the energy management chip 6, and energy transmission is realized by an external load.

[0071] The operating principle of the present invention is as follows: After visible light is focused by an optical antenna 1, a photoelectric conversion device 2 converts the optical signal into an electrical signal (simultaneously converting the optical energy into electrical energy). The electrical signal (and the electrical energy) are then transmitted to an information and energy separation circuit 3, forming a first output (corresponding to the information transmission branch) and a second output (corresponding to the energy transmission branch), which serve as inputs to the information output submodule and the energy output submodule, respectively. The first output of the information and energy separation circuit 3 undergoes pre-amplification, filtering, amplification, and shaping processing in the information output submodule before being output from the information output terminal. The second output of the information and energy separation circuit 3 serves as input to the energy output submodule.

[0072] The energy output submodule has three paths (such as Figure 3The energy output submodule threshold output port 19, energy output submodule output port 9 and low-voltage difference linear regulator output port 20) output: the input signal is stored in the energy storage unit 7 under the control of the energy management chip 6. When the voltage across the internal capacitor of the energy storage unit 7 reaches a certain value, a voltage within the threshold range is output as the first output (i.e., the energy output submodule threshold output port 19), which in turn powers the preamplifier unit 10 and the filter amplifier unit 11 of the information output submodule; the second output is output from the VOUT2 pin of the energy management chip 6, and this output is divided into two sub-paths. The first sub-path powers the external load (i.e., the energy output submodule output port 9), and the second sub-path is connected to the power input port of the built-in low-voltage difference linear regulator of the energy management chip 6 (i.e., the VIN-LDO pin of the energy management chip 6) to power the low-voltage difference linear regulator; the third output is output from the VOUT-LDO pin of the energy management chip 6 (i.e., the low-voltage difference linear regulator output port 20), outputting a stable voltage to simultaneously power the reference unit 14 and the shaping unit 12. When the information output port and the energy output port generate effective output at the same time, the device realizes the function of synchronous transmission of visible light information and energy.

[0073] The present invention cooperates with the energy management chip and the energy output submodule and the information output submodule. Compared with the technical solution in the prior art that uses a DC-DC boost circuit to solve the problem of maximizing the transmission power of energy storage and photoelectric conversion devices, it can achieve energy collection and management without the need for an external auxiliary signal, and thus will not interfere with the target information, and has the advantage of low noise. At the same time, the present invention realizes continuous power supply to the device itself and efficient energy utilization by providing a backup power supply in the energy input unit and an energy storage unit composed of two-stage capacitors in the energy output submodule, greatly improving the endurance of the Internet of Things terminal equipment, and has the advantages of wireless communication, security, speed and high endurance.

[0074] The above embodiments are merely preferred embodiments for the purpose of fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are within the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

Claims

1. An Internet of Things terminal device based on visible light information and energy transmission, characterized by: It includes a receiving module and an output module, the output module includes an energy output submodule and an information output submodule, the energy output submodule includes an energy input unit, an energy management chip, an energy storage unit and an energy output unit, and the energy input unit includes a backup power supply; The receiving module receives the visible light beam and converts it into electrical energy and electrical information, and the receiving module inputs the electrical energy into the energy output submodule through the energy input unit; The energy management chip is respectively connected to the energy input unit, the energy storage unit, the energy output unit and the backup power supply. The energy management chip stores the electric energy in the energy storage unit, manages the electric energy and supplies power to the device itself and the external load through the energy output unit. When the electric energy is insufficient, the energy management chip manages the backup power supply to supply power to the device itself and the external load. The receiving module is connected to the information output submodule, the receiving module inputs the electrical information into the information output submodule, and the information output submodule processes the electrical information and outputs it; The receiving module includes an optical antenna, a photoelectric conversion device and an information and energy separation circuit, wherein the output end of the optical antenna is connected to the input end of the photoelectric conversion device, and the output end of the photoelectric conversion device is connected to the input end of the information and energy separation circuit; The information and energy separation circuit includes an information transmission branch and an energy transmission branch connected in parallel, the output end of the information transmission branch is connected to the information output submodule, and the output end of the energy transmission branch is connected to the energy output submodule; The optical antenna collects the visible light beam and inputs it into the photoelectric conversion device, and the photoelectric conversion device converts the collected visible light beam into electrical energy and electrical information and inputs it into the information and energy separation circuit; The information and energy separation circuit separates the electrical energy and electrical information, inputs the electrical information into the information output submodule through the information transmission branch, and inputs the electrical energy into the energy output submodule through the energy transmission branch; The energy output submodule further includes a first threshold setting unit and a second threshold setting unit, wherein the first threshold setting unit and the second threshold setting unit are respectively connected to the energy management chip; The energy management chip has a built-in low voltage drop linear regulator, and the energy output unit includes an energy output submodule threshold output port, an energy output submodule output port and a low voltage drop linear regulator output port connected to the energy management chip; The energy management chip supplies power to the external load through the output port of the energy output submodule, and the energy management chip supplies power to the information output submodule through the threshold output port of the energy output submodule and the output port of the low voltage drop linear regulator; The first threshold setting unit adjusts the output voltage range of the energy output submodule threshold output port and the energy output submodule output port through the energy management chip, and the second threshold setting unit adjusts the output voltage size of the low-dropout linear regulator output port through the energy management chip; The first threshold setting unit includes a first resistor, a second resistor and a third resistor, both ends of the first resistor and the second resistor are connected to the energy management chip, and both ends of the third resistor are connected to the energy management chip and the ground line respectively; The second threshold setting unit includes a fourth resistor, a fifth resistor and a sixth capacitor, wherein both ends of the fourth resistor are connected to the energy management chip, both ends of the fifth resistor are connected to the energy management chip and a ground line, and both ends of the sixth capacitor are connected to both ends of the fourth resistor; The information output submodule includes a preamplifier unit, a filtering and amplifying unit, a shaping unit and an information output submodule output port. The output end of the preamplifier unit is connected to the input end of the filtering and amplifying unit, the output end of the filtering and amplifying unit is connected to the input end of the shaping unit, and the output end of the shaping unit is connected to the output port of the information output submodule. The information output submodule outputs an electrical signal through the information output submodule output port.

2. The IoT terminal device based on visible light information and energy transmission according to claim 1, characterized in that: The energy storage unit includes a third capacitor, a fourth capacitor and a second diode. The capacitance value of the third capacitor is smaller than the capacitance value of the fourth capacitor. The positive poles of the third capacitor and the fourth capacitor are respectively connected to the energy management chip. The negative poles of the third capacitor and the fourth capacitor are both grounded. The positive pole of the second diode is connected to the positive pole of the fourth capacitor, and the negative pole of the second diode is connected to the positive pole of the third capacitor.

3. The IoT terminal device based on visible light information and energy transmission according to claim 1, characterized in that: The information output submodule further includes a reference unit, the reference unit including a zeroth operational amplifier, a ninth resistor, a tenth resistor, a sixteenth capacitor, and a seventeenth capacitor; One end of the tenth resistor is grounded, and the other end of the tenth resistor is connected to the non-inverting input terminal of the zeroth operational amplifier; one end of the ninth resistor is connected to the non-inverting input terminal of the zeroth operational amplifier, and the other end of the ninth resistor is connected to the energy management chip; One end of the sixteenth capacitor and the seventeenth capacitor connected in parallel is grounded, and the other end of the sixteenth capacitor and the seventeenth capacitor connected in parallel is connected to the energy management chip; The reference unit is connected to the preamplifier unit, the filter amplifier unit, and the shaping unit respectively, and provides a stable reference voltage for the preamplifier unit, the filter amplifier unit, and the shaping unit.

4. The IoT terminal device based on visible light information and energy transmission according to claim 3, characterized in that: The preamplifier unit includes a transimpedance amplifier and a reference voltage input port. The transimpedance amplifier includes a first operational amplifier chip. The non-inverting end of the first operational amplifier chip is provided with the reference voltage input port. When the reference voltage output by the reference unit is input into the non-inverting end of the first operational amplifier chip, the output voltage of the transimpedance amplifier is raised by a reference through the reference voltage input port.

5. The IoT terminal device based on visible light information and energy transmission according to claim 3, characterized in that: The filtering and amplifying unit includes a second operational amplifier, an eleventh capacitor, a seventh resistor, and an eighth resistor, wherein the eleventh capacitor and the eighth resistor are connected in parallel to form a low-pass filter; the seventh resistor is connected to the inverting input terminal of the second operational amplifier, and the seventh resistor, the eighth resistor, and the second operational amplifier form an inverting amplifier; The shaping unit includes a comparator, a non-phase port of the comparator is connected to the output port of the filtering and amplifying unit, and an inverting port of the comparator is connected to the output port of the reference unit.

6. The IoT terminal device based on visible light information and energy transmission according to claim 3, characterized in that: The output of the energy output submodule includes a first output, a second output and a third output. The first output is the energy management chip supplying power to the preamplifier unit and the filter amplifier unit through the threshold output port of the energy output submodule. The second output includes a first sub-path and a second sub-path, the first sub-path is for the energy management chip to supply power to an external load through the output port of the energy output sub-module, and the second sub-path is for the energy management chip to supply power to the built-in low voltage drop linear regulator; The third output is that the energy management chip supplies power to the reference unit and the shaping unit through the output port of the low voltage difference linear regulator.

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