Passive wireless sensor system and power consumption method

Abstract

The application discloses a passive wireless sensor system and a power utilization method, which comprises an electromagnetic charging energy storage circuit and a sensing information transceiving circuit; the electromagnetic charging energy storage circuit is used for realizing power supply of the sensing information transceiving circuit and comprises a radio frequency rectification and charging energy storage module; the sensing information transceiving circuit is used for wireless information retransmission and comprises an information transmitting module, an information receiving module, a control and storage module, a sensor and a power supply energy switch. The information receiving module is used for acquiring a handshake signal of a self party; the control and storage module is used for controlling the energy switch, and the sensor completes sensing information collection. On the one hand, the electromagnetic charging energy storage circuit is used to solve the problem that the battery replacement work of a large number of small sensors is heavy or even difficult to replace; on the other hand, the control and storage module can control the power supply of the information transmitting module in time according to needs by controlling the energy switch, so that the energy consumption is reduced, the electromagnetic radiation leakage is reduced, and the risk of the sensor system being detected by electronic detection is reduced.

Description

Technical Field

[0001] This invention relates to a passive wireless sensor system and its power supply method, belonging to the field of wireless sensor network technology. Background Technology

[0002] The front end of the physical sensing layer of a wireless sensor network typically consists of various sensors and wireless communication transceiver modules, enabling the collection and wireless transmission of sensor information. From the perspective of the dimensions of sensor information collected, there are multi-dimensional information such as temperature, humidity, voltage, and current; from the perspective of wireless communication transmission and reception modes, there are various communication modes such as Bluetooth, RFID, and LoRa. A typical wireless sensor network application is a fitness tracker. It first collects vital signs information by placing sensors close to the user's arm, then transmits the information to a mobile phone via Bluetooth. The phone then stores, processes, and displays the sensor information. The fitness tracker's power supply is typically provided by a built-in battery that is periodically charged. However, with the continuous advancement of ubiquitous IoT technology, the demand for information sensing will become "everywhere and all time," leading to a massive increase in the number of sensing targets. Furthermore, sensor nodes are increasingly exhibiting characteristics such as multi-dimensional information, diverse types, and increasingly miniaturized structures. The sheer number and dispersed deployment of sensor nodes make powering them increasingly difficult, to the point that in many situations, it is almost impossible to manually replace the batteries of each sensor individually. This situation, in turn, severely hinders the further promotion and application of sensor nodes. Therefore, in recent years, long-distance, far-field wireless electromagnetic charging energy storage has gradually become a technological trend. Once this technology matures, it is expected to achieve long-distance, large-area, far-field coverage charging, which can greatly expand the application fields of wireless passive sensor nodes.

[0003] However, there are still many shortcomings in long-distance, far-field wireless charging energy storage technology, including: due to the limited electromagnetic power in space, the overall efficiency of the charging conversion circuit is relatively low; in terms of power consumption of wireless sensors, most of them are in the "charge and use" mode, so the overall energy storage power of the sensor node is low and the energy storage voltage stability is insufficient, which directly affects the reliability of the sensor power supply. In addition, when wireless sensor nodes are used on a large scale and in a dense manner, if the large amount of electromagnetic radiation waves scattered in space are not controlled, they will first generate a lot of energy consumption and waste energy, and at the same time generate a lot of electromagnetic leakage pollution, and there is a risk of electromagnetic space exposure. In highly confrontational situations, it is easy for the enemy to detect, locate and destroy it.

[0004] Regarding the energy supply of existing micro-miniature sensor nodes, the existing far-field radio frequency charging technology has a relatively simple charging and power consumption scheme. As a result, it leads to two problems: firstly, low energy storage conversion efficiency, and secondly, large power waste and loss of nodes. Specifically, it is reflected in the following aspects: (1) The charging frequency is single and the power is small, and the charging dynamic range is limited. Charging and communication share the same spatial electromagnetic waves, which means that sensor charging and communication are mostly at the same frequency and power. However, in actual demand, the power demand for communication is generally lower than the power demand for charging. Therefore, the electromagnetic waves that can meet the communication demand may not be able to ensure effective electromagnetic charging, resulting in the overall low conversion efficiency of far-field electromagnetic charging. In addition, the frequency designed for wireless charging circuits is mostly the same as the communication frequency, which means that other high-power electromagnetic radiation sources of different frequencies cannot charge it. The charging circuit is not adaptable, which is another reason for the low conversion efficiency of far-field electromagnetic charging. (2) The charging mode is not optimized enough, the charging time is short and the energy storage is insufficient. Currently, most passive wireless sensor node far-field electromagnetic charging technologies operate on a "charge-and-use" basis, meaning they charge only when communication is needed and stop charging when not needed. However, in practical applications, most sensors communicate intermittently on demand. Therefore, existing sensor node charging is often designed for intermittent charging as well. Due to limited charging time and insufficient energy storage, it's often difficult to sustain sensor operation for longer sampling times. Furthermore, during the numerous communication gaps, even if rechargeable electromagnetic waves are present, the lack of energy storage circuitry results in energy waste. Consequently, current passive wireless sensors are mostly low-energy-consuming types such as temperature sensors. High-energy-consuming sensor types rarely use passive wireless solutions. Moreover, even existing passive wireless temperature sensor solutions suffer from insufficient energy storage, resulting in low transmission distance and reliability.

[0005] (3) The power supply scheme is not well controlled, resulting in high energy consumption and easy electromagnetic leakage. At present, when the power supply voltage of the passive wireless sensor node is charged to a certain level to meet the circuit operation, the sensor immediately uses echo reflection to transmit information. The transmission time is uncontrolled and cannot distinguish between friend and foe, resulting in high energy consumption and easy electromagnetic detection and positioning, making it easy to be destroyed.

[0006] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a passive wireless sensor system and power supply method. On the one hand, an electromagnetic charging energy storage circuit is added. Unlike the traditional sensor "charge and use" mode, it adopts a "continuous charging, charging and use separation" mode, which can acquire electromagnetic charging signals for charging and energy storage, thereby improving energy storage efficiency and power supply reliability. On the other hand, based on the sensor information transceiver circuit, the sensor can control the signal transmission of the information transmission module by controlling the energy switch. The power consumption time of the information transmission module is reduced, the sensor energy consumption is reduced, and the standby time is further increased.

[0008] To achieve the above objectives, the present invention is implemented using the following technical solution: On one hand, the present invention discloses a passive wireless sensor system, including an electromagnetic charging energy storage circuit and a sensing information transceiver circuit; The electromagnetic charging energy storage circuit includes an RF rectification module and a charging energy storage module; the RF rectification module is used to acquire electromagnetic charging signals; based on the electromagnetic charging signals, rectification and filtering are performed to obtain an RF rectified output voltage; the charging energy storage module is used to charge and store energy based on the RF rectified output voltage to power the sensor information transceiver circuit. The sensing information transceiver circuit includes an information transmitting module, an information receiving module, a control and storage module, a sensor, and an energy switch. The energy switch is located at the power supply terminal of the information transmitting module. The information receiving module is used to acquire the handshake signal of its own device. The control and storage module is used to output a first control command based on the handshake signal to control the opening and closing of the energy switch, thereby powering the information transmitting module. Based on the handshake signal, it outputs a second control command to control the sensor to complete the sensing information acquisition. The sensor is used to acquire sensing information based on the second control command, and the obtained sensing information is transmitted to its own device via the control and storage module and the information transmitting module.

[0009] Furthermore, it also includes a wideband antenna, which is connected to the radio frequency rectification module, the information transmission module, and the information receiving module respectively; The wideband antenna includes multiple antennas for charging and communication, each independent of the other, and / or an integrated charging and communication antenna; The bandwidth of the wideband antenna includes 30MHz~87.975MHz, 433MHz, 915MHz, 2.4GHz and 5GHz.

[0010] Furthermore, the electromagnetic charging signal includes the frequency signal used for communication by the sensor itself, maliciously applied interference frequency signals, and charging signals specifically provided by other devices.

[0011] Furthermore, the RF rectification module includes a wideband multi-channel matching circuit unit, a wide power multi-stage rectification circuit unit, a sampling load, and an energy feedback control unit; The sampling load is used to sample the RF rectified output voltage, obtain the sampled voltage, and output it to the energy feedback control unit. The energy feedback control unit is used to output a frequency control signal and / or a power control signal based on the sampled voltage and a preset internal reference voltage. The wideband multi-channel matching circuit unit is used to configure the corresponding matching circuit according to the frequency control signal, so as to realize the automatic matching of electromagnetic charging signals with different input frequencies. The wide-power multi-channel matching circuit unit is used to configure the corresponding number of rectifier circuit stages according to the power control signal, so as to realize the automatic matching of electromagnetic charging signals with different input power.

[0012] Furthermore, the charging energy storage module includes a charging unit and an energy storage battery. The charging unit is used to identify the RF rectified output voltage; wherein, when the RF rectified output voltage is higher than the voltage of the energy storage battery, the RF rectified output voltage is directly transmitted to the energy storage battery to achieve charging and energy storage of the energy storage battery; when the RF rectified output voltage is lower than or equal to the voltage of the energy storage battery, the RF rectified output voltage is boosted before being transmitted to the energy storage battery to achieve charging and energy storage of the energy storage battery.

[0013] Furthermore, the energy storage battery includes a compound rechargeable battery and / or a supercapacitor.

[0014] Furthermore, the energy storage battery is connected to the information receiving module, the energy switch, the control and storage module, and the sensor respectively, so as to provide power to the information receiving module, the energy switch, and the sensor; The control terminal of the energy switch is connected to the control and storage module. The control and storage module is used to output a first control command to control the energy switch to close, thereby realizing the power supply and information transmission of the information transmission module.

[0015] On the other hand, the present invention also discloses a power supply method for a passive wireless sensor system, applicable to the aforementioned control and storage module, characterized by comprising the following steps: The handshake signal of one's own device is obtained through the information receiving module; Based on the handshake signal, a first control command is output to control the energy switch to close, thereby powering the information transmission module. Based on the handshake signal, a second control command is output to control the sensor to complete the acquisition of sensing information; wherein, the sensing information acquired by the sensor is transmitted to the user device via the control and storage module and the information transmission module.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: This invention, on the one hand, adds an electromagnetic charging energy storage circuit. Unlike the traditional "charge and use" mode of sensors, it adopts a "continuous charging, charging and use separation" mode, which can acquire electromagnetic charging signals for charging and energy storage, improving energy storage efficiency and power supply reliability. On the other hand, based on the sensor information transceiver circuit, the control and storage module can control the signal transmission of the information transmission module by controlling the energy switch, which can control the echo reflection of the information transmission module, reduce useless transmission power, improve wireless transmission reliability and prevent electromagnetic detection. At the same time, the power consumption time of the information transmission module is reduced, the sensor energy consumption is reduced, and the standby time is further increased.

[0017] The present invention also incorporates a wideband antenna to facilitate the reception of electromagnetic charging signals over a wide frequency range. Furthermore, the electromagnetic charging signals of the present invention are not limited to the communication frequency signals of the sensor itself, but also include maliciously applied interference frequency signals, charging signals supplied by other devices, and a series of other signals, greatly expanding the sources of charging frequencies.

[0018] The present invention also improves the radio frequency rectification module by outputting frequency control signals or power control signals through the energy feedback control unit to achieve automatic matching of electromagnetic charging signals with different input frequencies or different input powers. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a passive wireless sensor system module. Figure 2 This is a schematic diagram of an RF rectifier module; Figure 3 This is a schematic diagram of a charging energy storage module; Figure 4 This is a schematic diagram of an energy switch; Figure 5 This is a signal flow diagram of a passive wireless sensor system. Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention. Example 1

[0021] This embodiment 1 provides a passive wireless sensor system, including an electromagnetic charging energy storage circuit and a sensing information transceiver circuit; The electromagnetic charging energy storage circuit includes an RF rectifier module and a charging energy storage module. The RF rectifier module is used to acquire the electromagnetic charging signal. Based on the electromagnetic charging signal, it performs rectification and filtering to obtain the RF rectified output voltage. The charging energy storage module is used to charge and store energy based on the RF rectified output voltage to power the sensor information transceiver circuit. The sensor information transceiver circuit includes an information transmitting module, an information receiving module, a control and storage module, a sensor, and an energy switch. The energy switch is located at the power supply terminal of the information transmitting module. The information receiving module is used to acquire the handshake signal of its own device. The control and storage module is used to output a first control command based on the handshake signal to control the opening and closing of the energy switch, thereby powering the information transmitting module. Based on the handshake signal, it outputs a second control command to control the sensor to complete the acquisition of sensor information. The sensor is used to acquire sensor information based on the second control command, and the acquired sensor information is transmitted to its own device via the control and storage module and the information transmitting module.

[0022] Specifically, such as Figure 1 As shown, the passive wireless sensor system also includes a wideband antenna, which is connected to the radio frequency rectification module, the information transmission module, and the information reception module.

[0023] Wideband antennas include multiple antennas for charging and communication, and / or an integrated charging and communication antenna.

[0024] The bandwidth of the wideband antenna includes 30MHz~87.975MHz, 433MHz, 915MHz, 2.4GHz and 5GHz.

[0025] It should be noted that multiple antennas are used for charging and communication, meaning that the charging directional antenna and the communication omnidirectional antenna are designed separately for independent operation. The charging directional antenna enables directional electromagnetic radiation energy storage, and also includes intelligent directional illumination of the smart antenna's radiation lobes.

[0026] like Figure 2 As shown, the RF rectification module includes a wideband multi-channel matching circuit unit, a wide power multi-stage rectification circuit unit, a sampling load, and an energy feedback control unit; The sampling load is used to sample the output voltage, obtain the sampled voltage, and output it to the energy feedback control unit. An energy feedback control unit is used to output a frequency control signal and / or a power control signal based on the sampled voltage and a preset internal reference voltage. A wideband multi-channel matching circuit unit is used to configure the corresponding matching circuit according to the frequency control signal in order to achieve automatic matching of electromagnetic charging signals with different input frequencies. The wide-power multi-channel matching circuit unit is used to configure the corresponding number of rectifier circuit stages according to the power control signal, so as to realize the automatic matching of electromagnetic charging signals with different input power.

[0027] It should be noted that the frequency range of the wideband multi-channel matching circuit unit is consistent with that of the wideband antenna; the power range of the wide-power multi-channel matching circuit unit includes 0.01W to 100W. The RF rectified output voltage is a DC voltage with a certain ripple factor.

[0028] An automatic frequency control loop formed by a sampling load, an energy feedback control unit, and a wideband multi-channel matching circuit unit can control and select the optimal filter for different input frequencies, achieving multi-frequency signal energy reception and rectification conversion over a wide frequency range. This expands the sources of RF energy replenishment and improves the overall power of energy storage. It also enables automatic tracking of multiple input frequencies, thereby achieving automatic matching of electromagnetic charging signals at different input frequencies and enabling charging over a wide frequency range.

[0029] An automatic power control loop formed by a sampling load, an energy feedback control unit, and a wide-power multi-channel matching circuit unit can control the number of rectifier circuit stages under different input power levels, achieving an optimized balance between RF rectifier output power and conversion efficiency. This optimizes the output efficiency of the RF rectifier module across a wide input power range, thereby enabling automatic matching of electromagnetic charging signals with different input power levels and achieving charging over a wide power range.

[0030] It should be noted that the automatic frequency control loop and the automatic power control loop can be used individually or simultaneously.

[0031] Furthermore, the acquired electromagnetic charging signals include the communication frequency signals used by the sensor itself, maliciously applied interference frequency signals, and charging signals specifically provided by other devices. That is, the electromagnetic charging signals are not limited to the communication frequency of the wireless sensor itself, but also include high-power electromagnetic signals of the same or different frequencies that can be used for electromagnetic charging, appearing for any purpose. For example, high-power interference signals maliciously applied by the enemy during wartime, or high-power charging signals specifically provided by our unmanned equipment, can all be used for continuous charging of the sensor node. A typical feature of this far-field electromagnetic charging scheme is the wide power and wide frequency dynamic range of spatial electromagnetic signals that can be used for charging. For electromagnetic signal energy existing in space, regardless of the frequency band or application purpose, as long as it does not affect its normal operation, it can be incorporated into the charging electromagnetic energy source of the passive wireless sensor node. The acquired electromagnetic charging signals can independently charge and store energy in the electromagnetic charging energy storage circuit, and the sensor does not need to respond during charging.

[0032] like Figure 3 As shown, the charging and energy storage module includes a boost charging unit and an energy storage battery. The boost charging unit is used to identify the RF rectified output voltage. When the RF rectified output voltage is higher than the voltage of the energy storage battery, the RF rectified output voltage is directly transmitted to the energy storage battery to achieve charging and energy storage. When the RF rectified output voltage is lower than or equal to the voltage of the energy storage battery, the RF rectified output voltage is boosted before being transmitted to the energy storage battery to achieve charging and energy storage.

[0033] Energy storage batteries include compound rechargeable batteries and / or supercapacitors.

[0034] Specifically, the boost charging unit includes a first resistor R1, a second resistor R2, an error amplifier A, a MOSFET M, a filter capacitor C, a boost inductor L, a first unidirectional diode D1, a second unidirectional diode D2, and a control logic subunit. The logic control subunit is constructed by designing, programming, and then synthesizing the corresponding digital circuits. Its specific working principle is as follows: The RF rectifier module is connected to the control logic subunit, the energy storage battery, and the boost inductor L. The boost inductor L is connected to the energy storage battery through a unidirectional diode D2. The control logic subunit is connected to the gate of the MOSFET M through a gate drive circuit. The drain of the MOSFET M is connected between the boost inductor L and the unidirectional diode D2. One end of the first resistor R1 is connected between the unidirectional diode D2 and the energy storage battery, and the other end is connected in series with the second resistor R2. One input terminal of the error amplifier A is connected between the first resistor R1 and the second resistor R2, and the other end is connected to a reference voltage. The output terminal is connected to the control logic subunit. The reference voltage can be a bandgap reference voltage of 1.25V, or other reference voltages can be selected.

[0035] The control logic subunit is used to identify the RF rectified output voltage. In response to the RF rectified output voltage being higher than the voltage of the energy storage battery, the RF rectified output voltage is directly transmitted to the energy storage battery through the first unidirectional diode D1 to realize the charging and energy storage of the energy storage battery. In response to the RF rectified output voltage being lower than or equal to the energy storage battery voltage, the RF rectified output voltage is boosted by the boost inductor L and then transmitted to the energy storage battery through the second unidirectional diode D2 to achieve energy storage charging.

[0036] MOSFET M is a high-power voltage regulator. Together with the second unidirectional diode D2, the first resistor R1 and the second resistor R2, the error amplifier A, the control logic subunit, and the gate drive circuit, it forms a voltage feedback amplifier that can automatically stabilize the output voltage while increasing the output power. Because MOSFET M has high power, a gate drive circuit is added to drive it in the circuit design.

[0037] It should be noted that a filter capacitor C is also provided between the second unidirectional diode D2 and the energy storage battery to filter out noise.

[0038] Unlike the existing "charge and use" mode, the electromagnetic charging energy storage circuit of this system adopts a "continuous charging, charging and use separation" mode. This allows sensor nodes to continuously receive spatial electromagnetic radiation power for silent charging and energy storage. It can receive the communication frequency of wireless sensors for both communication and charging, as well as any other frequency at any time for charging, greatly expanding the sources of charging frequencies. All charged energy is stored in the energy storage battery for backup. The energy storage power of this solution is much greater than that of the "charge and use" mode, significantly improving the reliability of the wireless charging power supply.

[0039] like Figure 1 , 4 As shown in Figure 5, the energy storage battery is connected to the information receiving module, the energy switch, the control and storage module, and the sensor respectively to provide power to the information receiving module, the information transmitting module, the control and storage module, and the sensor. The control terminal of the energy switch is connected to the control and storage module. The control and storage module is used to output the first control command to control the energy switch to close, thereby realizing the power supply and information transmission of the information transmission module.

[0040] Unlike the existing "charge, sense, and transmit" model, this system adopts a three-stage process from charging to sensing to transmission. The passive wireless sensor system charges and stores energy upon receiving an electromagnetic charging signal to complete the sensing information acquisition. Simultaneously, it listens for its own communication handshake signal to obtain the handshake protocol before triggering the transmission of sensing information. This avoids energy waste and enemy electromagnetic enticement, preventing electromagnetic detection and destruction.

[0041] Specifically, once the electromagnetic charging energy storage circuit detects an electromagnetic charging signal that can be used for charging and energy storage, it begins charging and storing energy to power the information receiving module, the control and storage module, and the sensor. The sensor receives power from the energy storage battery and completes the acquisition of sensing information.

[0042] The information receiving module is always in a blind receiving state. Only when the acquired information signal contains a handshake signal from its own device will it transmit the handshake signal to the control and storage module. The control and storage module outputs the first control command based on the handshake signal to control the energy switch to close, thereby powering the information transmitting module and enabling the information transmitting module to transmit signals.

[0043] Compared to conventional solutions where electromagnetic charging and communication forwarding occur almost simultaneously after receiving communication electromagnetic waves, this system avoids directly using the DC voltage output from the instant charging sensor when it needs power. Instead, it first stores electrical energy in a storage battery. Only after receiving a confirmation handshake signal from its own device will the information transmission module be powered and the signal transmitted to relay the sensor information, thus reducing the power consumption of the information transmission module.

[0044] In summary, the passive wireless sensor system of this invention significantly improves charging time, charging frequency range, and power range, which is beneficial to the overall improvement of electromagnetic energy storage efficiency. Furthermore, the controlled power consumption time and frequency effectively save power. Simultaneously, sufficient energy storage improves sensing accuracy and stability; the wireless transmission distance of the sensor is significantly increased; the low radiation of the sensor nodes enhances covert sensing and detection capabilities; and the reduced wireless transmission power consumption lowers sensor energy consumption and further extends standby time. Example 2

[0045] Example 2 provides a power supply method for a passive wireless sensor system, applicable to the control and storage module of Example 1, characterized by the following steps: The handshake signal of one's own device is obtained through the information receiving module; Based on the handshake signal, a first control command is output to control the energy switch to close, thereby powering the information transmission module. Based on the handshake signal, a second control command is output to control the sensor to complete the acquisition of sensing information; wherein, the sensing information acquired by the sensor is transmitted to the user device via the control and storage module and the information transmission module.

[0046] On the one hand, it reduces the power consumption of passive wireless sensor systems and extends standby time; on the other hand, it reduces the leakage of useless electromagnetic energy, enabling low-power, low-radiation sensing information detection and perception.

[0047] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A passive wireless sensor system, characterized in that, This includes electromagnetic charging energy storage circuits and information transceiver circuits; The electromagnetic charging energy storage circuit includes an RF rectification module and a charging energy storage module; the RF rectification module is used to acquire electromagnetic charging signals; based on the electromagnetic charging signals, rectification and filtering are performed to obtain an RF rectified output voltage; the charging energy storage module is used to charge and store energy based on the RF rectified output voltage to power the sensor information transceiver circuit. The sensing information transceiver circuit includes an information transmitting module, an information receiving module, a control and storage module, a sensor, and an energy switch, wherein the energy switch is located at the power supply terminal of the information transmitting module; The information receiving module is used to acquire the handshake signal of its own device; the control and storage module is used to output a first control command according to the handshake signal to control the opening and closing of the energy switch, so as to realize the power supply of the information transmitting module. Based on the handshake signal, a second control command is output to control the sensor to complete the acquisition of sensing information; the sensor is used to acquire sensing information according to the second control command, and the obtained sensing information is transmitted to the user device through the control and storage module and the information transmission module. The radio frequency rectification module includes a wideband multi-channel matching circuit unit, a wide power multi-channel matching circuit unit, a sampling load, and an energy feedback control unit. The sampling load is used to sample the RF rectified output voltage, obtain the sampled voltage, and output it to the energy feedback control unit. The energy feedback control unit is used to output a frequency control signal and / or a power control signal based on the sampled voltage and a preset internal reference voltage. The wideband multi-channel matching circuit unit is used to configure the corresponding matching circuit according to the frequency control signal, so as to realize the automatic matching of electromagnetic charging signals with different input frequencies. The wide-power multi-channel matching circuit unit is used to configure the corresponding number of rectifier circuit stages according to the power control signal, so as to realize the automatic matching of electromagnetic charging signals with different input power. The charging and energy storage module includes a boost charging unit and an energy storage battery; The boost charging unit is used to identify the RF rectified output voltage; wherein, when the RF rectified output voltage is higher than the voltage of the energy storage battery, the RF rectified output voltage is directly transmitted to the energy storage battery to achieve charging and energy storage of the energy storage battery; when the RF rectified output voltage is lower than or equal to the voltage of the energy storage battery, the RF rectified output voltage is boosted before being transmitted to the energy storage battery to achieve charging and energy storage of the energy storage battery.

2. The passive wireless sensor system according to claim 1, characterized in that, It also includes a wideband antenna, which is connected to the radio frequency rectification module, the information transmission module and the information receiving module respectively; The wideband antenna includes multiple antennas for charging and communication, each independent of the other, and / or an integrated charging and communication antenna; The bandwidth of the wideband antenna includes 30MHz~87.975MHz, 433MHz, 915MHz, 2.4GHz and 5GHz.

3. The passive wireless sensor system according to claim 1, characterized in that, The electromagnetic charging signal includes the frequency signal used for communication by the sensor itself, the frequency signal of maliciously applied interference, and the charging signal provided by other devices.

4. The passive wireless sensor system according to claim 1, characterized in that, The energy storage battery includes a compound rechargeable battery and / or a supercapacitor.

5. The passive wireless sensor system according to claim 1, characterized in that, The energy storage battery is connected to the information receiving module, the energy switch, the control and storage module, and the sensor respectively, so as to provide power to the information receiving module, the energy switch, the control and storage module, and the sensor. The control terminal of the energy switch is connected to the control and storage module. The control and storage module is used to output a first control command to control the energy switch to close, thereby realizing the power supply and information transmission of the information transmission module.

6. A power supply method for a passive wireless sensor system, applicable to the control and storage module according to any one of claims 1-5, characterized in that, Includes the following steps: The handshake signal of one's own device is obtained through the information receiving module; Based on the handshake signal, a first control command is output to control the energy switch to close, thereby powering the information transmission module. Based on the handshake signal, a second control command is output to control the sensor to complete the acquisition of sensing information; wherein, the sensing information acquired by the sensor is transmitted to the user device via the control and storage module and the information transmission module.

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