CN206650665U - A kind of underground magnetic induction wireless communicator - Google Patents
A kind of underground magnetic induction wireless communicator Download PDFInfo
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- CN206650665U CN206650665U CN201720390767.9U CN201720390767U CN206650665U CN 206650665 U CN206650665 U CN 206650665U CN 201720390767 U CN201720390767 U CN 201720390767U CN 206650665 U CN206650665 U CN 206650665U
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Abstract
It the utility model is related to a kind of underground magnetic induction wireless communicator, traditional electromagnetic wave wireless communication technology is instead of with magnetic induction wireless communication technology, pass through the quasistatic magnetic field between dual-mode antenna i.e. " magnetic channel " transmission information in underground environment, communication channel is stable, it is lost in the absence of multipath, improves information transfer reliability.Dual-mode antenna uses spherical structure, it is made up of 3 identical conductor coils, coil is separate, it is mutually perpendicular between any two, 3 coils produce the three-dimensional magnetic field of an alternation jointly when sending signal, 3 coils induced field information from different directions during reception signal, therefore, do not influenceed between dual-mode antenna by coupling angle, information can be transmitted with any angle, and 3 coils receptions can increase communication distance.The utility model is simple in construction, and size is flexible, easy for installation, is also used as data reception node wirelessly descending in sensing network both to have may be used as data transmitting node, is easy to the transmitted in both directions of information between node.
Description
Technical field
The utility model belongs to underground wireless communication technical field, is related to a kind of underground magnetic induction wireless communicator.
Background technology
Wireless in-ground sensor network is that one to grow up on the basis of traditional wireless sensor networks is important emerging
Technical field, obtain widely should in multiple fields such as wisdom agricultural, mine rescue, geological hazards prediction, underground pipe network monitorings
With.Underground wireless communication technology is the key technology for wirelessly descending sensing network to develop.
Traditional wireless sensor network frequently with communication mode be electromagnetic wave wireless communication technology.It is wirelessly lower to sense
The transmission medium of information is become in order to which the complex medias such as soil, sandstone, moisture, electromagnetic wave radio communication face by air in device network
Stern challenge, is primarily present the problems such as path loss is high, channel is unstable, antenna size is big.It follows that electromagnetic wave without
Line communication technology is not suitable for underground environment, and the underground wireless communication technology of Development of Novel is that underground wirelessly descends sensing network to send out
The active demand of exhibition.
In order to solve electromagnetic communication under the complex environments such as underground, mine in complex media data transfer occur ask
Topic, researcher propose magnetic induction (Magnetic-Induction, MI) wireless communications method.Magnetic induction radio communication foundation
General principle is Faraday's electromagnetic induction law, and letter is realized by the coupling in quasistatic magnetic field between transmission antenna and reception antenna
Breath is wirelessly transferred, and because the transmission medium magnetic conductivity such as soil, sandstone, moisture is basically identical, so magnetic channel is stable, is not present
The problem of multipath is lost, and antenna size is excessive, wireless in-ground sensor network is more suitable for than electromagnetic wave radio communication.Magnetic strength
Answer radio communication theory highly developed and be verified in laboratory.In actual applications, based on transmitting and reception line
The magnetic induction manifold type wireless communication system that circle is formed is simplest mode, but single coil is during receiving and transmitting signal
It can be influenceed by angle is coupled between coil, this point limits the application of magnetic induction radio communication.
Utility model content
The problem of presently, there are for wireless communication technology in the complex environment of underground, the utility model provide a kind of underground magnetic
Induction wireless communicator, its dual-mode antenna are spherical structure, by three between any two orthogonal conductor coils form, tie
Structure is simple, channel is stable, receiving and transmitting signal is not influenceed by coupling angle, underground environment complicated and changeable is can adapt to, wireless
There is good feasibility and wide application prospect in the sensing network of underground.
The utility model proposes a kind of underground magnetic induction wireless communicator, including several to solve above-mentioned technical problem
Wireless communication unit, transmission of wireless signals is realized between adjacent wireless communication unit；Each wireless communication unit is by micro-
Processor, sending module, receiving module and dual-mode antenna composition, the microprocessor and sending module, dual-mode antenna, reception mould
Block and microprocessor are sequentially connected with, and form a signal transmission loop, and the dual-mode antenna is provided with numerical control switch, sending module
It is connected with receiving module by numerical control switch with dual-mode antenna, microprocessor is realized to dual-mode antenna by numerical control switch and received
With the conversion of transmitting；The dual-mode antenna is spherical structure, is intersected vertically two-by-two group by three isodiametric conductor coils respectively
Into, and the center of circle of three conductor coils overlaps；During installation, transmission direction order of the wireless communication unit along signal is set, and is made
Dual-mode antenna is centrally located atIn same horizontal line, form magnetic channel；During communication, microprocessor is loaded signal by transmitter module
Onto dual-mode antenna, dual-mode antenna is in emission state to next wireless communication unit transmission signal, next radio communication
The dual-mode antenna of unit is in reception state, receives and is transmitted to its microprocessor by receiving module after signal and is handled.
The microprocessor selects low-power consumption ARM chips, and the microprocessor connects sensor, for gathering environment letter
Breath；In addition, microprocessor is connected with toggle switch, encode for node address, read in when upper electric by microprocessor I/O ports
Node address.
The wireless communication unit is provided with modulating and demodulating signal circuit, from 2ASK modulation demodulation systems, its modulation circuit
It is arranged in transmitter module, demodulator circuit is arranged in receiving module, and signal modulation part passes through the UART built in microprocessor
Serial port function carries out coding generation baseband signal to the information that sensor gathers, and carrier signal, base are produced using crystal oscillator
Band signal and carrier signal realize that 2ASK is modulated by NAND gate circuit；The external timing resistor of signal demodulation part demodulation chip
The centre frequency of frequency selection circuit is set with electric capacity, and reception signal is by the frequency selection circuit of demodulation chip, by the presence or absence of carrier signal
0/1 baseband signal is converted into, realizes that 2ASK is demodulated.
The transmitter module includes signal modulation circuit and power amplification circuit, and wherein power amplification circuit uses resonant mode
Power amplification circuit is made up of large power triode, and modulated signal is loaded on dual-mode antenna by power amplification circuit.
The receiving module includes signal amplification circuit, narrow-band filtering circuit and signal demodulating circuit, and wherein signal amplifies
Circuit is made up of low noise triode, reception signal access demodulation chip after two-stage amplification, is included inside demodulation chip
One narrow band phase lock loop and a transistor switch, input signal is carried out to complete signal demodulation while narrow-band filtering.
The conductor coils are formed by copper wire coiling, one resonant capacitance of both ends parallel connection, for improving transmitting-receiving efficiency,
Coil is separate, and radius and the number of turn are determined by use environment.One resonant capacitance of each conductor coils both ends parallel connection, is used for
Transmitting-receiving efficiency is improved, resonant capacitance value C is together decided on by coil actual measurement inductance value L and signal transmission frequency f, and its calculation formula isDelivery and reception module is connected by numerical control switch with spherical antenna, controls numerical control to open by microprocessor
Close can be achieved data send and receive between switching.
A kind of communication means of underground magnetic induction wireless communicator, the signal at the both ends that communicate are passed in the form of magnetic signal
Defeated, the magnetic channel of dual-mode antenna composition had both sent magnetic signal or had received magnetic signal, concretely comprised the following steps：
1) the original baseband signal of transmitting terminal generates the sine wave signal I of an alternation by modulating amplification afterwards1=I0e-jwt, by I1It is loaded into simultaneously on three conductor coils of transmission antenna, the magnetic of an alternation is produced around each conductor coils
, the conductor coils of three pairwise orthogonals produce the three-dimensional magnetic field of an alternation jointly, and now electric signal is converted into magnetic signal, leads to
Magnetic field is crossed to send information；
2) receiving terminal reception antenna is in the magnetic field of alternation, and the magnetic flux in each of which conductor coils enclosed region is with friendship
The magnetic field of change changes, and is induced in three conductor coils and I1The sinusoidal signal I of same phase feature2、I'2、I″2, three
The conductor coils of pairwise orthogonal induced field information from different directions, is converted into electric signal, by three road electric signals by magnetic signal
Amplify demodulation after being superimposed by adder and restore raw information.
Beneficial effect：The utility model instead of traditional electromagnetic wave radio communication skill with magnetic induction wireless communication technology
Art, by the quasistatic magnetic field between dual-mode antenna i.e. " magnetic channel " transmission information in underground environment, communication channel is stable, no
Multipath loss be present, improve information transfer reliability.Dual-mode antenna uses spherical structure, by 3 identical conductor coils
Form, coil is separate, is mutually perpendicular between any two, and 3 coils produce the Three-Dimensional Magnetic of an alternation jointly when sending signal
, 3 coils induced field information from different directions during reception signal, therefore, not by coupling angle between dual-mode antenna
Influence, information can be transmitted with any angle, and 3 coils receptions can increase communication distance.The utility model is simple in construction,
Size is flexible, easy for installation, connects wirelessly descending in sensing network both to have may be used as data transmitting node to be also used as data
Node is received, is easy to the transmitted in both directions of information between node.
Brief description of the drawings
Fig. 1 is the underground magnetic induction wireless Communication System Design block diagram involved by the utility model.
Fig. 2 is the magnetic induction wireless receiving and dispatching antenna structure view involved by the utility model.
Fig. 3 is the 2ASK modulating and demodulating signal schematic diagrames involved by the utility model.
Fig. 4 is the underground radio sensing network node workflow diagram based on magnetic induction wireless communication technology.
Embodiment
Specific implementation method of the present utility model is further described below in conjunction with the accompanying drawings：
As shown in figure 1, a kind of wirelessly descend magnetic induction communicator to include several wireless communication units, adjacent is wireless
Transmission of wireless signals is realized between communication unit；Each wireless communication unit is by microprocessor, sending module, receiving module
Being formed with dual-mode antenna, the microprocessor is sequentially connected with sending module, dual-mode antenna, receiving module and microprocessor,
A signal transmission loop is formed, the dual-mode antenna is provided with numerical control switch, and sending module and receiving module are opened by numerical control
Pass is connected with dual-mode antenna, and microprocessor realizes the conversion received with transmitting by numerical control switch to dual-mode antenna.It is micro- during communication
Signal is loaded on dual-mode antenna by processor by transmitter module, and dual-mode antenna is in emission state to next radio communication list
First transmission signal, the dual-mode antenna of next wireless communication unit are in reception state, passed after receiving signal by receiving module
Handled to its microprocessor.The present apparatus both may be used as data transmitting node and be also used as data in radio sensing network
Receiving node.
The microprocessor selects the STM32 family chips based on ARM kernels of ST Microelectronics's production, the chip
With abundant peripheral resources, it is connected in sensor network with different types of sensor, for rings such as collecting temperature, humidity
Environment information.Toggle switch is connected with microprocessor, is encoded for node address, is read in when upper electric by microprocessor I/O ports
Node address.Transmitting terminal：The information of sensor collection is exported after microprocessor coding by serial ports, the data signal of output
Modulation circuit is accessed, power amplification circuit is accessed after ASK is modulated, induced field intensity and electric current when magnetic strength induction signal is sent
Size is directly proportional, and in order to obtain larger emission current with less power consumption, resonant mode is formed from high current triode 8550
To modulated signal enhanced processing, the signal after amplifying accesses dual-mode antenna by numerical control switch and sent out (Class C) power amplification circuit
See off.Receiving terminal：Antenna induction Magnetic Field, when communication distance farther out when the antenna reception signal that couples to obtain it is very micro-
It is weak, reception signal progress high power is put from the composition two-stage amplifying circuit of low noise triode 9014 in order to extend communication distance
Greatly, the signal access demodulation chip after amplifying, accesses microprocessor by serial ports after being demodulated by ASK, passes through microprocessor
Decoding reads raw information.
As shown in Fig. 2 the dual-mode antenna is spherical structure, respectively by three isodiametric conductor coils vertical phase two-by-two
Composition is handed over, and the center of circle of three conductor coils overlaps.During installation, transmission direction order of the wireless communication unit along signal is set,
And it is centrally located at dual-mode antennaIn same horizontal line, form magnetic channel.Each conductor coils by the coiling of copper wire and
Into radius and the number of turn are determined by use environment, one resonant capacitance of coil both ends parallel connection, for improving transmitting-receiving efficiency, resonance electricity
Capacitance C is together decided on by coil actual measurement inductance value L and signal transmission frequency f, and its calculation formula isIn order to
With various sizes of dual-mode antenna, resonant capacitance selects tunable capacitor device.The device passes through the quasistatic between dual-mode antenna
Magnetic field is " magnetic channel " transmission information.The original baseband signal of transmitting terminal generates the sine of an alternation by modulating amplification afterwards
Ripple signal I1=I0e-jwt, by I1It is loaded on three conductor coils of transmission antenna, can be produced around each conductor coils simultaneously
The magnetic field of a raw alternation, the conductor coils of three pairwise orthogonals produce the three-dimensional magnetic field of an alternation jointly, now electric signal
Magnetic signal is converted into, is sent information by magnetic field；Receiving terminal reception antenna is in the magnetic field of alternation, each conductor
Magnetic flux in coil enclosed region changes with the magnetic field of alternation, can be induced in three conductor coils and I1Same phase is special
The sinusoidal signal I of sign2、I'2、I″2, the conductor coils of three pairwise orthogonals induced field information from different directions, by magnetic signal
Electric signal is converted into, amplifies demodulation after three road electric signals are superimposed by adder and restores raw information.
As shown in figure 3, the present apparatus selects 2ASK modulation demodulation systems, 2ASK modulation is also known as OOK (On-Off Keying)
Modulation, is carried out data transmission with 100% energy, and circuit is simple, and demodulation is easy, improves system reliability.The micro- place of modulated terminal
The information that the node address information of reading and sensor gather is carried out coding generation baseband signal by reason device, is exported by serial ports,
250KHZ crystal oscillator produces carrier signal, and baseband signal and carrier signal realize 2ASK by 74HC00 NAND gate circuits
Modulation；Demodulating end selects integrated phase-locked loop chip LMC567, and frequency selection circuit is set by external timing resistor and electric capacity
The presence or absence of carrier signal is converted into 0/1 baseband signal, in fact by centre frequency, reception signal by the frequency selection circuit of demodulation chip
Existing 2ASK demodulation.
A kind of embodiment of underground magnetic induction wireless communication means of the present utility model, in conjunction with the embodiments and Fig. 4 is to this
The course of work of utility model is described further.The utility model is to be directed to a kind of specially designed underground magnetic strength of underground environment
Wireless communications method is answered, is mainly used in wirelessly descending sensing network, the present apparatus both may be used in self-organizing sensing network is wirelessly descended
Data reception node is also used as use as data transmitting node, it is possible to achieve half-duplex operation between node.With wisdom agricultural
Exemplified by sensing network, during the present apparatus is placed into the soil, different types of sensor is connected, temperature, the humidity of soil can be gathered
Etc. information.Fig. 4 is monitoring node workflow diagram, is mainly included the following steps that：
Step 1, monitoring node system electrification, progress Initialize installation, including microprocesser initialization and sensor are initial
Change, read in node address, opening timing device, subsequently into reception pattern；
Step 2, determine whether that information needs to receive in the receiving mode, kept if needing to receive without information
Wait reception state；If information needs to receive then receive information and extracts reception address information, by receiving address information
Judge whether to be destined to the data of this node, if it is read data, preserve and show, if not being then switched to transmission
Pattern forwards this information, then switches back to reception pattern and continues to remain waiting for reception state.
Step 3, if waiting reception period timer count to reach 5s (timing is set according to application demand),
The environmental informations such as sensor collecting temperature, humidity are then waken up, sending mode is switched to after having gathered information, the information of collection is added
Sent after the letter of upper transmitting-receiving address, then switch back to reception pattern, into wait reception state.
Claims (6)
1. a kind of underground magnetic induction wireless communicator, it is characterised in that including several wireless communication units, adjacent is wireless
Transmission of wireless signals is realized between communication unit；Each wireless communication unit is by microprocessor, sending module, receiving module
Being formed with dual-mode antenna, the microprocessor is sequentially connected with sending module, dual-mode antenna, receiving module and microprocessor,
A signal transmission loop is formed, the dual-mode antenna is provided with numerical control switch, and sending module and receiving module are opened by numerical control
Pass is connected with dual-mode antenna, and microprocessor realizes the conversion received with transmitting by numerical control switch to dual-mode antenna；The transmitting-receiving
Antenna is spherical structure, and intersected vertically two-by-two by three isodiametric conductor coils forms respectively, and the circle of three conductor coils
The heart overlaps；During installation, transmission direction order of the wireless communication unit along signal is set, and it is same to be centrally located at dual-mode antenna
On horizontal line, magnetic channel is formed；During communication, signal is loaded on dual-mode antenna by microprocessor by transmitter module, dual-mode antenna
In emission state to next wireless communication unit transmission signal, the dual-mode antenna of next wireless communication unit, which is in, to be received
State, receive and its microprocessor is transmitted to by receiving module after signal handled.
A kind of 2. underground magnetic induction wireless communicator according to claim 1, it is characterised in that the microprocessor choosing
With low-power consumption ARM chips, the microprocessor connects sensor, for gathering environmental information；In addition, microprocessor is opened with dial-up
Connection is connect, and is encoded for node address, and node address is read in by microprocessor I/O ports when upper electric.
A kind of 3. underground magnetic induction wireless communicator according to claim 1, it is characterised in that the radio communication list
Member is provided with modulating and demodulating signal circuit, and from 2ASK modulation demodulation systems, its modulation circuit is arranged in transmitter module, demodulation electricity
Road is arranged in receiving module, the letter that signal modulation part is gathered by the UART serial port functions built in microprocessor to sensor
Breath carries out coding generation baseband signal, and carrier signal is produced using crystal oscillator, baseband signal and carrier signal by with it is non-
Gate circuit realizes that 2ASK is modulated；The external timing resistor of signal demodulation part demodulation chip and electric capacity set the center of frequency selection circuit
The presence or absence of carrier signal is converted into 0/1 baseband signal, realized by frequency, reception signal by the frequency selection circuit of demodulation chip
2ASK is demodulated.
A kind of 4. underground magnetic induction wireless communicator according to claim 1 or 3, it is characterised in that the transmitting mould
Block includes signal modulation circuit and power amplification circuit, and wherein power amplification circuit uses resonance type power amplifying circuit by big work(
Rate triode is formed, and modulated signal is loaded on dual-mode antenna by power amplification circuit.
A kind of 5. underground magnetic induction wireless communicator according to claim 1 or 3, it is characterised in that the reception mould
Block includes signal amplification circuit, narrow-band filtering circuit and signal demodulating circuit, and wherein signal amplification circuit is by low noise triode
Composition, reception signal access demodulation chip after two-stage amplification, a narrow band phase lock loop and one are included inside demodulation chip
Individual transistor switch, input signal is carried out to complete signal demodulation while narrow-band filtering.
A kind of 6. underground magnetic induction wireless communicator according to claim 1, it is characterised in that the conductor coils by
Copper wire coiling forms, and one resonant capacitance of both ends parallel connection, for improving transmitting-receiving efficiency, coil is separate, radius and circle
Number is determined by use environment.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107094031A (en) * | 2017-04-14 | 2017-08-25 | 中国矿业大学 | A kind of underground magnetic induction wireless communicator and method |
| CN108691534A (en) * | 2018-05-11 | 2018-10-23 | 中国石油天然气集团有限公司 | A kind of downhole electromagnetic wireless telecommunication system and method |
| CN108964676A (en) * | 2018-07-09 | 2018-12-07 | 深圳市银河风云网络系统股份有限公司 | Radio transmitting device, method and electronic equipment |
| CN112487501A (en) * | 2020-11-12 | 2021-03-12 | 杭州云嘉云计算有限公司 | Equipment data security port identification system |
| CN114301553A (en) * | 2021-11-26 | 2022-04-08 | 军事科学院系统工程研究院网络信息研究所 | Communication method based on modulated magnetic field quantum precision measurement |
| CN115790673A (en) * | 2023-02-06 | 2023-03-14 | 国机传感科技有限公司 | Extremely-low-frequency electromagnetic wave bidirectional magnetic sensing device and method |
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2017
- 2017-04-14 CN CN201720390767.9U patent/CN206650665U/en active Active
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107094031A (en) * | 2017-04-14 | 2017-08-25 | 中国矿业大学 | A kind of underground magnetic induction wireless communicator and method |
| WO2018188355A1 (en) * | 2017-04-14 | 2018-10-18 | 中国矿业大学 | Underground magnetic-induction wireless communication device and method |
| CN108691534A (en) * | 2018-05-11 | 2018-10-23 | 中国石油天然气集团有限公司 | A kind of downhole electromagnetic wireless telecommunication system and method |
| CN108691534B (en) * | 2018-05-11 | 2022-03-29 | 中国石油天然气集团有限公司 | Underground electromagnetic wireless communication system and method |
| CN108964676A (en) * | 2018-07-09 | 2018-12-07 | 深圳市银河风云网络系统股份有限公司 | Radio transmitting device, method and electronic equipment |
| CN112487501A (en) * | 2020-11-12 | 2021-03-12 | 杭州云嘉云计算有限公司 | Equipment data security port identification system |
| CN112487501B (en) * | 2020-11-12 | 2024-04-16 | 杭州云嘉云计算有限公司 | Equipment data security port identification system |
| CN114301553A (en) * | 2021-11-26 | 2022-04-08 | 军事科学院系统工程研究院网络信息研究所 | Communication method based on modulated magnetic field quantum precision measurement |
| CN115790673A (en) * | 2023-02-06 | 2023-03-14 | 国机传感科技有限公司 | Extremely-low-frequency electromagnetic wave bidirectional magnetic sensing device and method |
| CN115790673B (en) * | 2023-02-06 | 2023-05-12 | 国机传感科技有限公司 | Extremely low frequency electromagnetic wave bidirectional magnetic sensing device and method |
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