Wireless sensor, wireless sensor network and interaction method thereof

Abstract

The present invention provides a wireless sensor, a wireless sensor network and an interaction method thereof. The wireless sensor provided by the embodiment of the invention comprises a receiver, a transmitter, a first antenna, a first switch module, a counting control module and a state control module. The wireless sensor controls the transmitting and receiving switch by a counting method, so that the transmitting and receiving share one antenna, thereby reducing the size of the node. The wireless sensor node designed in this way consumes little energy and meets the low power consumption and miniaturization requirements of the node.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a wireless sensor, a wireless sensor network and an interaction method thereof. Background Art

[0002] With the development of the Internet of Things and intelligent unmanned platforms, the demand for wireless sensor nodes is increasing. In the existing technology, wireless sensors are often powered by batteries or external energy. However, since wireless sensor nodes are not always in the transmitting state during the actual working process, the existing power supply method is not conducive to the effective use of energy and cannot meet the needs of efficient use of equipment resources in the future.

[0003] Therefore, how to achieve low power consumption of wireless sensor nodes to effectively utilize energy is a technical problem that needs to be solved urgently. Summary of the invention

[0004] The present invention provides a wireless sensor, a wireless sensor network and an interaction method thereof, which realize low power consumption of wireless sensor nodes.

[0005] A first aspect of the present invention provides a wireless sensor, comprising a receiver, a transmitter, a first antenna, a first switch module, a counting control module and a state control module; wherein the first switch module is used to conduct the receiver and the first antenna so that the receiver always maintains a normal working state, and the first switch module is also used to control the conduction or disconnection between the transmitter and the first antenna to control whether the transmitter is sent to the first antenna;

[0006] The output port of the counting control module is connected to the first switch module. When the output port of the counting control module sends a conduction control signal, the first switch module controls the transmitter to be connected to the first antenna, and when the output port of the counting control module sends a disconnection control signal, the first switch module controls the transmitter to be disconnected from the first antenna;

[0007] The output port of the counting control module is also connected to the first input port of the state control module, the output port of the state control module is connected to the control port of the transmitter, and the second input port of the state control module is connected to the output port of the receiver;

[0008] When the output port of the counting control module sends the conduction control signal and the receiver receives the power-off and non-operation control signal sent by the aggregation node, the output port of the state control module is controlled to output a first control signal for controlling the transmitter to be powered off and non-operational; and when the output port of the counting control module sends the conduction control signal and the receiver receives the normal operation control signal sent by the aggregation node, the output port of the state control module is controlled to output a second control signal for controlling the transmitter to operate normally;

[0009] In the case where the output port of the counting control module sends the disconnection control signal, the output port of the state control module is controlled to output a first control signal for controlling the transmitter to be powered off and not to work.

[0010] Optionally, the receiver is specifically used for:

[0011] When the power-off non-operating control signal is received, the power-off non-operating control signal is converted from frequency to amplitude to obtain a corresponding first amplitude and output it from the output port of the receiver; accordingly, the state control module is specifically used to control the output port of the state control module to output the first control signal when it is determined that the first amplitude is greater than a preset reference amplitude;

[0012] When the normal working control signal is received, the normal working control signal is frequency-amplitude converted to obtain a corresponding second amplitude and output it from the output port of the receiver; accordingly, the state control module is specifically used to control the output port of the state control module to output the second control signal when it is determined that the second amplitude is less than a preset reference amplitude.

[0013] Optionally, a transmission spectrum of the wireless sensor is outside a frequency band where a reception spectrum is located.

[0014] Optionally, the power-off non-operating control signal is a sine wave with a frequency of f0, and the normal operating control signal is a sine wave with a frequency of f1, and f0 deviates from f1.

[0015] Optionally, two parameters N1 and N2 are set in the counting control module, and N2>N1. The counting control module is specifically used for:

[0016] When the count is from 1 to N1, the count control module outputs the on control signal, and when the count is from 1+N1 to N2, the count control module outputs the off control signal.

[0017] Optionally, the first switch module includes a first end, a second end and a third end;

[0018] The first end is connected to the transmission port of the transmitter, the second end is connected to the first antenna, and the third end is used to connect or disconnect the first end and the second end.

[0019] A second aspect of the present invention provides a wireless sensor network, comprising a plurality of wireless sensors as provided in the first aspect, and a sink node, wherein the plurality of wireless sensors are wirelessly connected to the sink node; the sink node comprises a second switch module and a second antenna;

[0020] The receiver of the aggregation node keeps a normal working state, and controls the conduction or disconnection between the transmitter of the aggregation node and the second antenna through the second switch module to control whether the transmitter of the aggregation node sends to the second antenna.

[0021] A third aspect of the present invention provides an interaction method of the wireless sensor network based on the second aspect, comprising: the method comprising:

[0022] When the count increases from 1 to N1, the count control module outputs the conduction control signal, and the aggregation node sends the power-off non-operation control signal or the normal operation control signal to the wireless sensor to control the transmitter of the wireless sensor.

[0023] Optionally, the counting control module restarts counting from 0 after counting to N2.

[0024] Optionally, the conduction control signal output by the counting control module is at a low level, and correspondingly, the second control signal is also at a low level;

[0025] The disconnection control signal output by the counting control module is at a high level, and accordingly, the first control signal is also at a high level.

[0026] The wireless sensor, wireless sensor network and interaction method thereof provided by the present invention, the wireless sensor provided by the embodiment of the present invention, controls the transmitting and receiving switch by a counting method, so that the transmitting and receiving share one antenna, thereby reducing the size of the node. The wireless sensor node designed in this way consumes little energy and meets the low power consumption and miniaturization requirements of the node. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1It is a schematic diagram of the structure of a wireless sensor provided by an embodiment of the present invention.

[0029] Figure 2 A schematic diagram of frequency band division of a wireless sensor network provided by an embodiment of the present invention.

[0030] Figure 3 This is one of the principle diagrams of the frequency amplitude converter provided in an embodiment of the present invention.

[0031] Figure 4 A schematic diagram of a frequency-to-amplitude conversion curve provided by an embodiment of the present invention.

[0032] Figure 5 The second schematic diagram of the frequency amplitude converter provided in the embodiment of the present invention.

[0033] Figure 6 A schematic diagram of the state control module structure provided in an embodiment of the present invention.

[0034] Figure 7 A schematic diagram of the structure of a first switch module provided in an embodiment of the present invention.

[0035] Figure 8 A schematic diagram of the wireless sensor network structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In order to achieve low power consumption of wireless sensor nodes, effectively utilize energy, and reduce the size of nodes, an embodiment of the present invention provides a counting method to control the transmit and receive switch so that the transmit and receive share one antenna. This method increases energy consumption very little and meets the low power consumption and miniaturization requirements of the nodes.

[0038] Figure 1 is a schematic diagram of the structure of a wireless sensor provided by an embodiment of the present invention, such as Figure 1 As shown, the wireless sensor includes: a frequency amplitude converter 11, such as the frequency amplitude converter 11 shown in the figure, a VCO 12, such as the voltage controlled oscillator VCO 12 shown in the figure, a first antenna 13, a first switch module 14, a counting control module 15 and a state control module 16.

[0039] Among them, the first switch module 14 is used to conduct the frequency-amplitude converter 11 and the first antenna 13 so that the frequency-amplitude converter 11 always maintains a normal working state, and the first switch module 14 is also used to control the conduction or disconnection between the VCO 12 and the first antenna 13 to control whether the VCO 12 is sent to the first antenna 13. That is to say, in the wireless sensor provided by the embodiment of the present invention, the frequency-amplitude converter 11 always maintains a conduction state with the first antenna 13, that is, the frequency-amplitude converter 11 is always working, and the wireless sensor controls whether the VCO 12 is sent to the first antenna 13 through the first switch module sw2 to control when the VCO 12 is in a sending state.

[0040] like Figure 1 As shown, the wireless sensor provided by the embodiment of the present invention may also include a thermoelectric generator TEG, an energy management circuit, an energy storage and a temperature sensor, etc. The energy management circuit collects energy from the TEG. The wireless sensor converts the temperature into a frequency and sends it out, and the frequency amplitude converter 11 converts the command state of the aggregation node into an amplitude to control the sensor node.

[0041] The output port sw of the counting control module 15 is connected to the first switch module 14. When the output port sw of the counting control module 15 sends a conduction control signal (for example, outputting a low level through sw), the first switch module 14 controls the VCO 12 to be connected with the first antenna 13, and when the output port sw of the counting control module 15 sends a disconnection control signal (for example, outputting a high level through sw), the first switch module 14 controls the VCO 12 to be disconnected from the first antenna 13. In other words, the counting control module 15 can control the conduction or disconnection between the VCO 12 and the first antenna 13 by outputting different control signals (for example, a low level or a high level) through sw at different stages.

[0042] The output port sw of the counting control module 15 is also connected to the first input port c0 of the state control module 16, the output port cn of the state control module 16 is connected to the control port pd of the VCO 12, and the second input port in of the state control module 16 is connected to the output port o of the frequency-amplitude converter 11. The control signal output by the counting control module 15 through the output port sw enters the state control module 16 from the first input port c0, which can affect the signal output of the output port cn of the state control module 16. Further, the output port cn of the state control module 16 is connected to the control port pd of the VCO 12, and its signal output can affect the working state of the VCO 12. The second input port in of the state control module 16 is connected to the output port o of the frequency-amplitude converter 11, so that the output signal of the frequency-amplitude converter 11 can also simultaneously affect the signal output of the output port cn of the state control module 16. Specifically, when the output port sw of the counting control module 15 sends a conduction control signal (for example, outputting a low level through sw) and the frequency-amplitude converter 11 receives a power-off non-operation control signal (for example, FM2) sent by the sink node, the output port cn of the control state control module 16 outputs a first control signal for controlling the VCO 12 to be powered off and non-operational (for example, outputting a high level through cn), and when the output port (sw) of the counting control module sends the conduction control signal (sw=0) and the frequency-amplitude converter 11 receives a normal operation control signal (for example, FM1) sent by the sink node, the output port cn of the control state control module 16 outputs a second control signal for controlling the VCO 12 to be operated normally (for example, outputting a low level through cn). When the output port sw of the counting control module 15 sends a disconnection control signal (for example, outputting a high level through sw), the output port cn of the control state control module 16 outputs a first control signal for controlling the VCO 12 to be powered off and non-operational (for example, outputting a high level through cn).

[0043] In this embodiment, the output port sw of the counting control module 15 sends a low level signal or sends the level signal, which can be controlled based on different counting stages, for example, different control signals are sent in different counting ranges. For example, two parameters N1 and N2 are set in the counting control module 15, and N2>N1, and the counting control module 15 is specifically used for: when the count is from 1 to N1, the counting control module 15 outputs a conduction control signal (sw is a low level signal), and when the count is from 1+N1 to N2, the counting control module 15 outputs a disconnection control signal (sw is a high level signal).

[0044] The wireless sensor provided by the embodiment of the present invention controls the transmitting and receiving switch by counting method, so that the transmitting and receiving share one antenna, thereby reducing the size of the node. The wireless sensor node designed in this way consumes little energy and meets the low power consumption and miniaturization requirements of the node.

[0045] On the basis of the above embodiment, the frequency-amplitude converter 11 is specifically used for: when receiving a power-off non-operating control signal (e.g., FM2), performing frequency-amplitude conversion on the power-off non-operating control signal (FM2), obtaining a corresponding first amplitude and outputting it from the output port o of the frequency-amplitude converter 11; accordingly, the state control module 16 is specifically used for controlling the output port cn of the state control module 16 to output a first control signal (e.g., outputting a high level through cn) when it is determined that the first amplitude is greater than a preset reference amplitude.

[0046] When a normal working control signal (for example, FM1) is received, the normal working control signal (FM1) is frequency-amplitude converted to obtain a corresponding second amplitude and output it from the output port o of the frequency-amplitude converter 11; accordingly, the state control module 16 is specifically used to control the output port cn of the state control module 16 to output the second control signal (for example, output a low level through cn) when it is determined that the second amplitude is less than a preset reference amplitude.

[0047] Figure 2 A schematic diagram of frequency band division of a wireless sensor network provided in an embodiment of the present invention is shown in FIG. Figure 2 As shown, the embodiment of the present invention includes m sensor node transmission frequency bands TX_Fi (i=1,…,m) and receiving frequency bands RX_Fi (i=1,…,m). It can be seen that the transmission spectrum of the same wireless sensor node is outside the frequency band where the receiving spectrum is located, that is, the influence of transmission on reception is negligible. The aggregation node communicates with the sensor node through a set frequency band. For example, when a sensor node communicates with a aggregation node, the sensor node sends to the aggregation node in the TX_F1 frequency band, and the aggregation node sends to the sensor node in the RX_F1 frequency band. It can be seen that the signal in the TX_F1 frequency band has been attenuated to a negligible degree at the RX_F1 frequency band, that is, the transmission signal of the sensor node does not affect its own receiving signal.

[0048] Figure 3 One of the principle diagrams of the frequency amplitude converter provided by the embodiment of the present invention, Figure 4 A frequency-to-amplitude conversion curve diagram provided by an embodiment of the present invention is shown in FIG. Figure 3 and Figure 4 As shown, the transformer secondary coil is connected in parallel with capacitor C1, and the FM wave is input from the transformer primary coil. Due to the resonance between the secondary coil inductance and the capacitor, the conversion curve between the FM wave frequency and the AM wave output amplitude is obtained as shown in Figure 4 f0 is the resonant frequency of the secondary coil inductance and capacitance. It can be seen that the curve is bandpass, and the output amplitude of f0 is the largest. The larger the frequency difference with f0, the smaller the output amplitude.

[0049] Figure 5The second schematic diagram of the frequency amplitude converter provided by the embodiment of the present invention is as follows: Figure 5 As shown, the gate voltage is provided to the MOS tube M0 through the voltage division of resistors R1 and R2. C1 and C2 are the DC isolation capacitors for input and output respectively. The resonant frequency of the load inductor L0 and the load capacitor C0 is f0. The conversion curve between the FM wave frequency and the output amplitude is as follows: Figure 4 It can be seen that the curve is bandpass, and the output amplitude is the largest at f0. The larger the frequency difference with f0, the smaller the output amplitude.

[0050] Figure 6 A schematic diagram of the state control module structure provided by an embodiment of the present invention, such as Figure 6 As shown, the state control module 16 determines the amplitude of different FM frequency conversions through a comparator. Assume that n frequency modulation signals FM1, ..., FMn are supported, and the frequency-to-amplitude conversion is performed into n amplitude signals v1, ..., vn, satisfying the monotonic v1 < ... < vn. When there is no input signal in the receiving circuit, it is equivalent to the input signal frequency being 0 (dc), as shown in FIG. Figure 4 It can be seen that dc is farther away from f0, so the output amplitude is smaller, set to vDC. v0 is the output amplitude corresponding to the resonant frequency f0. Then the relationship between the comparator level and the amplitude is set to vDC<vref1<v1<…<vrefn<vn≤v0; when c0 is high, the output<cn,…,c1> When c0 is low,<cn,…,c1> Determined by the ratio of in to vref1,…,vrefn.

[0051] Based on this, in the wireless sensor network provided by the embodiment of the present invention, the power-off non-operating control signal FM2 sent by the sink node may be a sine wave with a frequency of f0, and the normal operating control signal FM1 may be a sine wave with a frequency of f1, and f0 deviates from f1.

[0052] Figure 7 A schematic diagram of the structure of a first switch module provided in an embodiment of the present invention is shown in FIG. Figure 7 As shown, the first switch module 14 includes a first terminal 1, a second terminal 2 and a third terminal 3; wherein the first terminal 1 is connected to the transmitting port of the VCO 12, the second terminal 2 is connected to the first antenna 13, and the third terminal 3 is used to connect or disconnect the first terminal 1 and the second terminal 2. Specifically, M1 and M3 are pmos, and M2 and M4 are nmos. C2 is a DC blocking capacitor. When the third terminal 3 is high, the first terminal 1 is disconnected from the second terminal 2, and when the third terminal 3 is low, the first terminal 1 is connected to the second terminal 2.

[0053] Figure 8 A schematic diagram of the wireless sensor network structure provided by an embodiment of the present invention is shown in FIG. Figure 8As shown, the structure of the aggregation node and sensor node of the wireless sensor network and the spectrum allocation scheme are given to realize the transceiver networking. Among them, it includes multiple wireless sensors provided by the above embodiments, and the aggregation node, and the multiple wireless sensors are wirelessly connected to the aggregation node, and the aggregation node includes a second switch module sw2 and a second antenna. In order to avoid the problem of receiving lost data due to the fact that the aggregation node and the sensor node communicate with each other at a different clock, the embodiment of the present invention proposes a method in which the receiver is always working and the transmission and reception spectrum isolation is realized through the frequency selection characteristics of the receiver. Specifically, the FM receiver of the aggregation node maintains a normal working state, that is, it is always working, and the conduction or disconnection between the FM transmitter of the aggregation node and the second antenna is controlled by the second switch module sw2 to control whether the FM transmitter of the aggregation node is sent to the second antenna. The sensor node receives the command FM signal sent by the aggregation node, and different frequencies represent different commands. Through the frequency to amplitude conversion, the converted amplitude (in) is compared and judged, and the control signal cn is output. The FM transmitter and the FM receiver are connected to the digital processing, and the digital processing is connected to the host computer by wire. Since the aggregation node and the sensor node receiver are always working, this avoids the problem of receiving lost data caused by clock asynchrony.

[0054] The following provides an interactive method of a wireless sensor network based on the above embodiment, combined with Figure 1 As shown, when the VCO pd signal is high, the VCO is powered off and does not work, and when the pd signal is low, the VCO works normally. The counting control module has two parameters N1 and N2 (N2>N1).

[0055] 1. When the count goes from 1 to N1, the output o of the counting control module is low level, that is, the sending state:

[0056] 1) The state control module input c0 is equal to the count control module output o, which is low. Figure 6 Known output<cn,…,c1> Determined by the ratio of in to vref1,…,vrefn.

[0057] The input of the frequency-amplitude converter of this embodiment has two control FM signals from the sink node, one of which is selected: FM1 and FM2. FM1 represents that the wireless sensor node continues to work normally, and FM2 represents that the wireless sensor node turns off transmission. Assume that FM2 is a sine wave with a frequency of f0, and FM1 is a sine wave with a frequency that deviates greatly from f0.

[0058] When the signal is FM 2, the output amplitude of the frequency-amplitude converter is v0, at which time the output of cn is 1, and the VCO is powered off and does not work; when the signal is FM 1, the output amplitude of the receiving circuit is less than vrefn, the output of cn is 0, and the VCO works normally. It can be seen that the purpose of controlling the sensor node (for example, whether the VCO works or does not work after powering off) is achieved by converging the FM signals of the nodes (for example, FM1 and FM2).

[0059] 2) Switch 3 port is equal to the count control module output o is low level, by Figure 7 It can be seen that the VCO is connected to the antenna.

[0060] 2. When the count goes from 1+N1 to N2, the output o of the counting control module is high level, which means it is not sending:

[0061] 1) By Figure 1 It can be seen that the switch disconnects the VCO from the antenna;

[0062] 2) The state control module input c0 is high, the output<cn,…,c1> All are high, then cn output is 1, VCO is powered off and does not work, thus saving power consumption.

[0063] 3. After counting to N2, restart counting from 0.

[0064] Since the frequency amplitude converter does not require current and the current of the state control module is in the uA level, the increased current is very small compared with the traditional solution. It is suitable for use in self-powered wireless sensor networks to achieve control of wireless sensor nodes.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wireless sensor, characterized in that: include: A receiver, a transmitter, a first antenna, a first switch module, a counting control module and a state control module; wherein the first switch module is used to conduct the receiver and the first antenna so that the receiver always maintains a normal working state, and the first switch module is also used to control the conduction or disconnection between the transmitter and the first antenna to control whether the transmitter is sent to the first antenna; The output port of the counting control module is connected to the first switch module. When the output port of the counting control module sends a conduction control signal, the first switch module controls the transmitter to be connected to the first antenna, and when the output port of the counting control module sends a disconnection control signal, the first switch module controls the transmitter to be disconnected from the first antenna; The output port of the counting control module is also connected to the first input port of the state control module, the output port of the state control module is connected to the control port of the transmitter, and the second input port of the state control module is connected to the output port of the receiver; When the output port of the counting control module sends the conduction control signal and the receiver receives the power-off and non-operation control signal sent by the aggregation node, the output port of the state control module is controlled to output a first control signal for controlling the transmitter to be powered off and non-operational; and when the output port of the counting control module sends the conduction control signal and the receiver receives the normal operation control signal sent by the aggregation node, the output port of the state control module is controlled to output a second control signal for controlling the transmitter to operate normally; In the case where the output port of the counting control module sends the disconnection control signal, the output port of the state control module is controlled to output a first control signal for controlling the transmitter to be powered off and not to work.

2. The wireless sensor according to claim 1, characterized in that: The receiver is specifically used for: When the power-off non-operating control signal is received, the power-off non-operating control signal is converted from frequency to amplitude to obtain a corresponding first amplitude and output it from the output port of the receiver; accordingly, the state control module is specifically used to control the output port of the state control module to output the first control signal when it is determined that the first amplitude is greater than a preset reference amplitude; When the normal working control signal is received, the normal working control signal is frequency-amplitude converted to obtain a corresponding second amplitude and output it from the output port of the receiver; accordingly, the state control module is specifically used to control the output port of the state control module to output the second control signal when it is determined that the second amplitude is less than a preset reference amplitude.

3. The wireless sensor according to claim 1, characterized in that: The transmission spectrum of the wireless sensor is outside the frequency band where the receiving spectrum is located.

4. The wireless sensor according to claim 1, characterized in that: The power-off non-operating control signal is a sine wave with a frequency of f0, and the normal operating control signal is a sine wave with a frequency of f1, and f0 deviates from f1.

5. The wireless sensor according to any one of claims 1 to 4, characterized in that: The counting control module is provided with two parameters N1 and N2, and N2>N1. The counting control module is specifically used for: When the count is from 1 to N1, the count control module outputs the on control signal, and when the count is from 1+N1 to N2, the count control module outputs the off control signal.

6. The wireless sensor according to any one of claims 1 to 4, characterized in that: The first switch module includes a first end, a second end and a third end; The first end is connected to the transmission port of the transmitter, the second end is connected to the first antenna, and the third end is used to connect or disconnect the first end and the second end.

7. A wireless sensor network, characterized in that: The method comprises a plurality of wireless sensors according to any one of claims 1 to 6, and a sink node, wherein the plurality of wireless sensors are wirelessly connected to the sink node; the sink node comprises a second switch module and a second antenna; The receiver of the aggregation node keeps a normal working state, and controls the conduction or disconnection between the transmitter of the aggregation node and the second antenna through the second switch module to control whether the transmitter of the aggregation node sends to the second antenna.

8. An interaction method based on the wireless sensor network as claimed in claim 7, characterized in that: The method comprises: When the count increases from 1 to N1, the count control module outputs the conduction control signal, and the aggregation node sends the power-off non-operation control signal or the normal operation control signal to the wireless sensor to control the transmitter of the wireless sensor.

9. The wireless sensor network interaction method according to claim 8, characterized in that: The counting control module counts to N2 and then restarts counting from 0.

10. The wireless sensor network interaction method according to claim 8 or 9, characterized in that: The conduction control signal output by the counting control module is at a low level, and accordingly, the second control signal is also at a low level; The disconnection control signal output by the counting control module is at a high level, and accordingly, the first control signal is also at a high level.

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