CN115333554A - Through-the-earth communication method and device based on distance sensing - Google Patents

Abstract

The invention provides a distance sensing-based through-the-earth communication method and communication device. The communication method includes acquiring target information for transmission and converting it into a through-the-earth communication signal; and configuring the signal based on preset multiple pairs of buried electrodes. A pair of transmitting electrodes and a pair of shielding electrodes; the pair of signal transmitting electrodes forms a communication electric field through the voltage change between the electrode pairs, which is used to transmit a through-the-earth communication signal; the communication electric field carries the through-the-earth communication signal; the shielding electrode The structure is shielded from the electric field; the through-the-earth communication signal receiving device is used to receive the through-the-earth communication signal, and the target information is obtained by conversion. The invention can improve the signal transmission efficiency and quality of through-the-earth communication by setting the communication electric field and shielding electric field for communication signal transmission based on the buried electrode.

Description

A method and device for through-the-earth communication based on distance sensing

technical field

The present invention relates to the technical field of through-the-earth communication, in particular to a distance-sensing-based through-the-earth communication method and a communication device.

Background technique

At present, the electrode-through-the-ground communication technology is used in mining, tunnel rescue and other occasions. The electrode-through-the-earth communication technology adopts very low frequency or low frequency band, inserts the electrode into the soil layer, uses the soil layer as the dielectric, and the signal sent by the electrode at one end will pass through the soil layer to generate induction on the electrode at the other end, thereby transmitting information, but Since the depth and direction of buried electrodes are not fixed in the communication process of the electrode through-the-ground communication technology, the energy of the propagated signal will be attenuated. Improving the transmission efficiency in the process of the through-the-ground communication is a problem that needs to be solved.

Contents of the invention

The invention provides a distance sensing-based through-the-ground communication method and a communication device. A communication electric field and a shielding electric field for communication signal transmission are set based on buried electrodes, which can improve the signal transmission efficiency and quality of through-the-ground communication.

The invention provides a distance-sensing-based through-the-ground communication method, including:

S1: Obtain the target information for sending and convert it into a through-the-ground communication signal;

S2: Based on the preset multiple pairs of buried electrodes, configure the signal sending electrode pair and the shielding electrode pair; the signal sending electrode pair forms a communication electric field through the voltage change between the electrode pair, and is used to send a through-the-ground communication signal; the said The communication electric field carries the through-ground communication signal; the shielding electrode pair is configured to shield the electric field;

S3: Using the ground-penetrating communication signal receiving device to receive the ground-penetrating communication signal, convert and obtain target information.

Further, the voltage between the buried electrodes of the shielding electrode pair remains stable; the carrier frequency of the through-the-earth communication signal is in a very low frequency or low frequency band.

Further, S1 includes:

S101: Using software programming to complete the encoding and spread spectrum modulation of the target information, and generate spread spectrum modulation information;

S102: After using the single chip microcomputer to modulate the spread spectrum modulation information into a broadband pulse waveform, using a pulse shaping circuit to convert it into a through-the-earth communication signal.

Further, the spread spectrum modulation in S101 is: according to a preset prototype PN code, the prototype PN code is cyclically shifted to generate M mutually orthogonal PN codes, and the symbols with a number of types of M are spread one by one.

Further, S2 includes:

S201: Obtain the electromagnetic parameters of the through-the-earth channel according to the preset communication transmission standard;

S202: According to the conductivity value in the electromagnetic parameters of the ground-penetrating channel, calculate and obtain the depth of the ground-penetrating soil layer;

S203: Determine a first buried depth of the buried electrode according to the depth.

Further, S2 includes:

S204: Obtain the relationship between the electrode impedance value and the electrode buried depth value based on the preset electrode impedance model;

S205: Obtain the electrode impedance value according to the preset communication transmission standard, and calculate and obtain the second buried depth of the buried electrode according to the electrode impedance value;

S206: Calculate the weighted sum of the first buried depth and the second buried depth, and take an average value to obtain the buried depth of the buried electrode;

S207: Perform buried configuration for the buried electrodes according to the buried depth of the buried electrodes.

Further, S3 includes:

S301: Capture the received communication signal by adding a longer synchronization header to obtain the capture signal;

S302: Down-sampling the captured signal to obtain a bearer communication signal;

S303: Based on the bearer communication signal, obtain a spread spectrum signal with a chip length of L to perform FFT transformation, and then multiply it by the frequency domain value of the prototype PN code to obtain a first transformation sequence;

S304: Perform IFFT transformation on the first transformation sequence to obtain a sequence with a length of L, and despread the bearer communication signal according to the position of the peak value of the sequence to obtain a despread signal;

S305: Perform RS decoding on the despread signal to obtain target information.

Further, S4 is also included to suppress the communication interference of the through-ground communication signal:

S401: Intercepting the received through-the-ground communication signal according to a preset number of points to obtain the intercepted through-the-ground communication signal;

S402: Using polyphase filtering technology, filtering the intercepted through-the-ground communication signal through a high-order filter;

S403: Perform FFT calculation on the filtered communication signal to obtain an interference signal frequency higher than a preset threshold;

S404: Using a time-domain adaptive notch filter and using the frequency value of the interference signal as an initial value, perform time-domain narrowband interference suppression.

Further, it also includes S5, which detects signal attenuation and compensates;

S501: Set the fixed potential difference between the receiving end and the sending end of the through-the-earth communication signal under normal attenuation;

S502: Measure the potential difference generated after the receiving end receives the through-ground communication signal, and calculate the first difference between the potential difference and the fixed potential difference;

S503: Determine the attenuation compensation amount corresponding to the first difference according to the preset comparison table of the attenuation compensation amount and the absolute value of the first difference;

S504: When the first difference is a positive value, perform an increase operation according to the attenuation compensation amount; when the first difference value is a negative value, perform a decrease operation according to the attenuation compensation amount.

The present invention provides a through-the-ground communication device based on distance sensing, including:

The ground-penetrating communication signal acquisition module is used to acquire the target information to be sent and convert it into a ground-penetrating communication signal;

The setting module of the through-ground communication device is used to configure the signal sending electrode pair and the shielding electrode pair based on the preset multiple pairs of buried electrodes; the signal sending electrode pair forms a communication electric field through the voltage change between the electrode pairs for sending A ground-penetrating communication signal; the communication electric field carries the ground-penetrating communication signal; the shielding electrode pair is constructed to shield the electric field;

The through-the-ground communication signal receiving module is used for receiving the through-the-ground communication signal by using the through-the-ground signal receiving device, and converting it into target information.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and appended drawings.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, and are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention. In the attached picture:

FIG. 1 is a schematic diagram of the steps of a distance-sensing-based through-the-ground communication method of the present invention;

Fig. 2 is a schematic diagram of steps of a method for receiving through-the-earth communication signals based on a distance sensing-based through-the-earth communication method of the present invention;

FIG. 3 is a schematic structural diagram of a through-the-earth communication device based on distance sensing according to the present invention.

Detailed ways

The preferred embodiments of the present invention will be described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

The present invention provides a ground-through communication method based on distance sensing, as shown in Figure 1, including:

S1: Obtain the target information for sending and convert it into a through-the-ground communication signal;

S2: Based on the preset multiple pairs of buried electrodes, configure the signal sending electrode pair and the shielding electrode pair; the signal sending electrode pair forms a communication electric field through the voltage change between the electrode pair, and is used to send a through-the-ground communication signal; the said The communication electric field carries the through-ground communication signal; the shielding electrode pair is configured to shield the electric field;

S3: Using the ground-penetrating communication signal receiving device to receive the ground-penetrating communication signal, convert and obtain target information.

The working principle of the above technical solution is as follows: by burying multiple pairs of electrodes, a communication electric field and a shielding electric field for communication signal transmission can be constructed to ensure the normal transmission of the through-the-earth communication signal; this embodiment obtains the target information for sending, and converts It is a communication signal through the ground; based on the preset multiple pairs of buried electrodes, the signal sending electrode pair and the shielding electrode pair are configured; the signal sending electrode pair forms a communication electric field through the voltage change between the electrode pairs, and is used to send the through-the-ground communication signal; the communication electric field carries the ground-penetrating communication signal; the shielding electrode pair is constructed to shield the electric field; the ground-penetrating communication signal receiving device is used to receive the ground-penetrating communication signal, and convert to obtain target information.

The beneficial effect of the above technical solution is: the solution provided by this embodiment can improve the signal transmission efficiency and quality of through-the-ground communication by scientifically setting the buried depth of electrodes based on distance sensing.

In one embodiment, the voltage between the buried electrodes of the shielding electrode pair remains stable; the carrier frequency of the through-the-earth communication signal is in a very low frequency or low frequency band.

The working principle of the above technical solution is: the voltage between the buried electrodes of the shielding electrode pair remains stable; the carrier frequency of the through-the-earth communication signal is in the very low frequency or low frequency band.

The beneficial effects of the above technical solution are: adopting the solution provided by this embodiment, by setting the voltage of the shielding electrode to the ground and the carrier frequency of the through-the-earth communication signal, the normal operation of the through-the-earth communication device is ensured.

In one embodiment, S1 includes:

S101: Using software programming to complete the encoding and spread spectrum modulation of the target information, and generate spread spectrum modulation information;

S102: After using the single chip microcomputer to modulate the spread spectrum modulation information into a broadband pulse waveform, using a pulse shaping circuit to convert it into a through-the-earth communication signal.

The working principle of the above-mentioned technical solution is as follows: the realization process of the through-the-earth communication is divided into two parts: receiving and transmitting, both of which are composed of hardware and software. For the structure of the hardware part of the transmitting end and the receiving end, it is realized by the control of a single-chip microcomputer; The method of software programming completes the encoding and spread spectrum modulation of the target information to generate spread spectrum modulation information; after the spread spectrum modulation information is modulated into a broadband pulse waveform by a single-chip microcomputer, it is converted into a through-the-earth communication signal by a pulse shaping circuit.

The beneficial effects of the above technical solution are: by adopting the solution provided by this embodiment, the target information can be better converted into the through-the-earth communication signal through the software system and the single-chip microcomputer hardware device.

In one embodiment, the spread spectrum modulation in S101 is: according to a preset prototype PN code, the prototype PN code is cyclically shifted to generate M mutually orthogonal PN codes, and the symbols with the number of types M are spread one by one. frequency.

The working principle of the above technical solution is: in order to better realize the coding gain, the combination of spread spectrum and coding is adopted, and the bit error rate performance can be improved according to the increase of the value of M; specifically: according to a preset prototype PN code, the prototype PN code is cyclically shifted to generate M mutually orthogonal PN codes, and the symbols with the number of types M are spread one by one.

The beneficial effects of the above technical solution are: the solution provided by this embodiment can increase the coding gain and reduce the computational complexity through the combination of spreading and coding.

In one embodiment, S2 includes:

S201: Obtain the electromagnetic parameters of the through-the-earth channel according to the preset communication transmission standard;

S202: According to the conductivity value in the electromagnetic parameters of the ground-penetrating channel, calculate and obtain the depth of the ground-penetrating soil layer;

S203: Determine a first buried depth of the buried electrode according to the depth.

The working principle of the above-mentioned technical solution is: soil is the medium for communication through the ground, and its electromagnetic parameters, such as electrical conductivity, dielectric constant, magnetic permeability, etc., affect and determine the propagation of communication signals in the soil, where the electrical conductivity reflects the soil The ability of the middle soil layer to conduct current. As the depth of the soil layer increases, the structure becomes more and more compact, and the humidity decreases, and the electrical conductivity is relatively low. As the depth continues to increase, the corresponding formation temperature increases and the electrical conductivity increases. According to this change, the depth of the soil layer of the ground-penetrating electrode is set; specifically: according to the preset communication transmission standard, the electromagnetic parameters of the ground-penetrating channel are obtained; according to the conductivity of the ground-penetrating channel Calculate the depth of the penetrating soil layer; according to the depth, determine the first buried depth of the buried electrode.

The beneficial effect of the above technical solution is: the solution provided by this embodiment can obtain the depth of the buried electrode through the conductivity, which can provide an effective reference data.

In one embodiment, S2 includes:

S204: Obtain the relationship between the electrode impedance value and the electrode buried depth value based on the preset electrode impedance model;

S205: Obtain the electrode impedance value according to the preset communication transmission standard, and calculate and obtain the second buried depth of the buried electrode according to the electrode impedance value;

S206: Calculate the weighted sum of the first buried depth and the second buried depth, and take an average value to obtain the buried depth of the buried electrode;

S207: Perform buried configuration for the buried electrodes according to the buried depth of the buried electrodes.

The working principle of the above technical solution is: when the electrode is inserted into the ground, a certain gap will be formed with the ground, thereby generating a certain capacitance value; the impedance of the electrode is related to the salinity, humidity, temperature, conductivity, etc. of the medium surrounding it and its Its material, length, diameter, shape, etc. are closely related. By increasing the contact area between the electrode and the ground, the impedance can be effectively reduced, that is, the deeper the electrode is buried in the ground, the smaller the value of the electrode impedance; according to this theory, the depth of the buried electrode required by the compound is also calculated; specifically: Based on The preset electrode impedance model obtains the relationship between the electrode impedance value and the electrode buried depth value; obtains the electrode impedance value according to the preset communication transmission standard, and calculates the second buried electrode according to the electrode impedance value Depth: Calculate the weighted sum of the first buried depth and the second buried depth and then take the average value to obtain the buried depth of the buried electrode; according to the buried depth of the buried electrode, the buried electrode is buried.

The beneficial effect of the above-mentioned technical solution is: adopting the solution provided in this embodiment, the second burial depth calculated by the electrode impedance model, combined with the first burial depth to calculate the comprehensive electrode burial depth, can ensure the burial depth The scientific and reasonable setting is conducive to the efficient transmission of ground-penetrating communication signals.

In one embodiment, as shown in Figure 2, S3 includes:

S301: Capture the received communication signal by adding a longer synchronization header to obtain the capture signal;

S302: Down-sampling the captured signal to obtain a bearer communication signal;

S303: Based on the bearer communication signal, obtain a spread spectrum signal with a chip length of L to perform FFT transformation, and then multiply it by the frequency domain value of the prototype PN code to obtain a first transformation sequence;

S304: Perform IFFT transformation on the first transformation sequence to obtain a sequence with a length of L, and despread the bearer communication signal according to the position of the peak value of the sequence to obtain a despread signal;

S305: Perform RS decoding on the despread signal to obtain target information.

The working principle of the above-mentioned technical solution is: this embodiment adopts the despreading scheme based on the transform domain, and the specific steps are:

S301: Capture the received communication signal by adding a longer synchronization header to obtain the capture signal;

S302: Down-sampling the captured signal to obtain a bearer communication signal;

S303: Based on the bearer communication signal, obtain a spread spectrum signal with a chip length of L to perform FFT transformation, and then multiply it by the frequency domain value of the prototype PN code to obtain a first transformation sequence;

S304: Perform IFFT transformation on the first transformation sequence to obtain a sequence with a length of L, and despread the bearer communication signal according to the position of the peak value of the sequence to obtain a despread signal;

S305: Perform RS decoding on the despread signal to obtain target information.

There are two methods to judge whether the received communication signal is captured: the threshold method and the method of finding the maximum value. In the threshold method, every time a correlation value is calculated, it is compared with the set threshold. If it is greater than the threshold, it means that the signal has been successfully captured and tracked. The method of finding the maximum value is to find a maximum value for each period. If the maximum value position occurs periodically, or is greater than the set threshold value, it is captured. The false alarm probability of the threshold method is greater than that of the maximum value method, but the probability of missed detection is smaller than that of the maximum value method. Simultaneously, the maximum value method needs longer capture time and takes more hardware resources; the present invention combines the threshold method and the maximum value method to improve the capture algorithm, and the specific steps are:

Step 1: Perform multi-channel parallel reception of communication signals, perform sliding correlation with local PN codes respectively, obtain multiple correlation values in every multiple sampling time intervals, subtract the correlation values of every two channels and then take the absolute value, After comparing them, keep the one with the largest absolute value as the judgment value, and record its relative position;

Step 2: Compare the judgment amount with the preset first threshold value, if it is less than the first threshold value, then repeat step 1 after receiving the communication signal sliding one bit, if the judgment amount is greater than the first threshold value, go to step 3;

Step 3: Every time the received signal slides one bit, step 1 is performed once, and a preset period value is repeated, and the maximum value is found among the calculated maximum values equal to the number of period values and its position is saved, in order to reduce the probability of missed detection , saving all positions of the received signal greater than a second threshold while finding the maximum value, the second threshold being higher than the first threshold;

Step 4: Receive the communication signal and continue to slide to see if the position one cycle away from the maximum value found in step 3 is greater than the second threshold. If it is greater than the second threshold, the signal is captured and entered into tracking. If the second threshold value is not reached, continue to slide to find the maximum value of this cycle and temporarily save the value greater than the second threshold value, and then compare with the value of the previous cycle to determine the position that is one cycle away from the maximum value Whether it is greater than the second threshold, if it is greater than the second threshold, it is captured, if it is less than the second threshold, then continue to step 3.

Based on the above steps, in the process of capturing communication signals, the calculation of the capture threshold has a direct relationship with the capture performance;

The above formula is the calculation formula of the false alarm probability obtained according to the noise distribution function, where _Pf is the false alarm probability value, s is the capture threshold, ^β2 is the variance of signal noise, k is the number of independent Gaussian random variables, i is a value located in the interval from s to infinity, s≤i<∞; when the capture threshold is low, the probability of false alarm capture is high; when the capture threshold is large, the probability of capture false alarm decreases, according to this relationship , an appropriate capture threshold can be selected.

The beneficial effects of the above technical solution are: adopting the solution provided by this embodiment, the decoding of the signal can be effectively realized through the despreading based on the transform domain, and accurate target information can be obtained; the improved capture based on the threshold method and the maximum value method The algorithm captures the communication signal, and can set an appropriate capture threshold under the condition of ensuring the original false alarm probability, so as to improve the capture probability.

In one embodiment, S4 is also included, suppressing the communication interference of the through-the-ground communication signal:

S401: Intercepting the received through-the-ground communication signal according to a preset number of points to obtain the intercepted through-the-ground communication signal;

S402: Using polyphase filtering technology, filtering the intercepted through-the-ground communication signal through a high-order filter;

S403: Perform FFT calculation on the filtered communication signal to obtain an interference signal frequency higher than a preset threshold;

S404: Using a time-domain adaptive notch filter and using the frequency value of the interference signal as an initial value, perform time-domain narrowband interference suppression.

The working principle of the above technical solution is: in the process of through-ground communication, there are various interferences, and the received voltage at the receiving end has an attenuation relationship with the distance, so as the communication distance increases, the received voltage value rapidly attenuates; because Ground-penetrating communication interference is narrow-band interference, which requires an effective method to suppress narrow-band interference. Time-domain narrow-band interference suppression technology can effectively suppress interference, but the convergence speed is slow. Frequency-domain narrow-band interference suppression technology is simple to implement and can suppress multiple narrow-band interferences. But it will increase the processing time and increase the delay; the present invention combines the time domain and frequency domain narrowband interference suppression algorithm to suppress the interference of the signal, specifically:

S401: Intercepting the received through-the-ground communication signal according to a preset number of points to obtain the intercepted through-the-ground communication signal;

S402: Using polyphase filtering technology, filtering the intercepted through-the-ground communication signal through a high-order filter;

S403: Perform FFT calculation on the filtered communication signal to obtain an interference signal frequency higher than a preset threshold;

S404: Using a time-domain adaptive notch filter and using the frequency value of the interference signal as an initial value, perform time-domain narrowband interference suppression.

The beneficial effects of the above technical solution are: the solution provided by this embodiment can improve the sensitivity of the receiving end of the through-the-earth communication signal to receive the signal by suppressing the interference of the through-the-earth communication signal.

In one embodiment, it also includes S5, detecting signal attenuation and performing compensation;

S501: Set the fixed potential difference between the receiving end and the sending end of the through-the-earth communication signal under normal attenuation;

S502: Measure the potential difference generated after the receiving end receives the through-ground communication signal, and calculate the first difference between the potential difference and the fixed potential difference;

S503: Determine the attenuation compensation amount corresponding to the first difference according to the preset comparison table of the attenuation compensation amount and the absolute value of the first difference;

S504: When the first difference is a positive value, perform an increase operation according to the attenuation compensation amount; when the first difference value is a negative value, perform a decrease operation according to the attenuation compensation amount.

The working principle of the above-mentioned technical solution is: because the attenuation caused in the signal transmission process will affect the quality of communication information transmission, it is necessary to detect and compensate the signal attenuation; the specific steps of the present invention are:

S501: Set the fixed potential difference between the receiving end and the sending end of the through-the-earth communication signal under normal attenuation;

S502: Measure the potential difference generated after the receiving end receives the through-ground communication signal, and calculate the first difference between the potential difference and the fixed potential difference;

S503: Determine the attenuation compensation amount corresponding to the first difference according to the preset comparison table of the attenuation compensation amount and the absolute value of the first difference;

S504: When the first difference is a positive value, perform an increase operation according to the attenuation compensation amount; when the first difference value is a negative value, perform a decrease operation according to the attenuation compensation amount.

The beneficial effects of the above technical solution are: the solution provided by this embodiment can effectively compensate the signal attenuation by detecting the attenuation situation and performing compensation, so as to ensure the quality of signal transmission.

The present invention provides a through-the-ground communication device based on distance sensing, as shown in Figure 3, including:

The ground-penetrating communication signal acquisition module is used to acquire the target information to be sent and convert it into a ground-penetrating communication signal;

The setting module of the through-ground communication device is used to configure the signal sending electrode pair and the shielding electrode pair based on the preset multiple pairs of buried electrodes; the signal sending electrode pair forms a communication electric field through the voltage change between the electrode pairs for sending A ground-penetrating communication signal; the communication electric field carries the ground-penetrating communication signal; the shielding electrode pair is constructed to shield the electric field;

The through-the-ground communication signal receiving module is used for receiving the through-the-ground communication signal by using the through-the-ground signal receiving device, and converting it into target information.

The working principle of the above technical solution is: by setting the through-the-earth communication signal acquisition module, the through-the-earth communication device setting module and the through-the-earth communication signal receiving module, the transmission and reception device for the through-the-earth communication signal is constructed; specifically: the through-the-earth communication signal acquisition module , used to obtain the target information to be sent, and convert it into a through-the-earth communication signal; the through-the-earth communication device setting module is used to configure the signal sending electrode pair and the shielding electrode pair based on the preset multiple pairs of buried electrodes; the signal The transmitting electrode pair forms a communication electric field through the voltage change between the electrode pair for sending the through-the-earth communication signal; the communication electric field carries the through-the-earth communication signal; the shielding electrode pair constructs a shielding electric field; the through-the-earth communication signal receiving module , for receiving the through-the-earth communication signal with the through-the-earth signal receiving device, and converting it into target information.

The beneficial effect of the above technical solution is: adopting the solution provided by this embodiment, by setting the communication electric field and shielding electric field for communication signal transmission based on buried electrodes, the signal transmission efficiency and quality of through-the-ground communication can be improved.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. A through-the-earth communication method based on distance induction is characterized by comprising the following steps:

s1: acquiring target information for transmission, and converting the target information into a through-the-earth communication signal;

s2: configuring a signal sending electrode pair and a shielding electrode pair based on a plurality of preset pairs of buried electrodes; the signal transmitting electrode pairs form a communication electric field through voltage change between the electrode pairs and are used for transmitting ground penetrating communication signals; the communication electric field bears the through-the-earth communication signal; the shielding electrode pair structure shields an electric field;

s3: and receiving the through-the-earth communication signal by using a through-the-earth communication signal receiving device, and converting to obtain target information.

2. The method according to claim 1, wherein S1 comprises: the voltage between the buried electrodes of the shielding electrode pair is kept stable; the carrier frequency of the through-the-earth communication signal is at a very low frequency or a low frequency band.

3. The method according to claim 1, wherein S1 comprises:

s101: the method comprises the steps of utilizing a software programming method to complete coding and spread spectrum modulation of target information and generating spread spectrum modulation information;

s102: after the spread spectrum modulation information is modulated into a broadband pulse waveform by the singlechip, the broadband pulse waveform is converted into a through-the-earth communication signal by a pulse shaping circuit.

4. The method according to claim 3, wherein the spread spectrum modulation in S101 is: according to a preset prototype PN code, the prototype PN code is circularly shifted to generate M mutually orthogonal PN codes, and the symbols with the types and the number of M are subjected to spread spectrum one by one.

5. The method for through-the-earth communication based on distance sensing of claim 1, wherein S2 comprises:

s201: acquiring electromagnetic parameters of a through-the-earth channel according to a preset communication transmission standard;

s202: according to the conductivity value in the through-the-earth channel electromagnetic parameters, calculating to obtain the depth of the through-the-earth soil layer;

s203: and determining a first buried depth of the buried electrode according to the depth.

6. The method according to claim 5, wherein S2 comprises:

s204: acquiring a relation between an electrode impedance value and an electrode buried depth value based on a preset electrode impedance model;

s205: acquiring an electrode impedance value according to a preset communication transmission standard, and calculating to obtain a second buried depth of the buried electrode according to the electrode impedance value;

s206: after the first buried depth and the second buried depth are subjected to weighted summation calculation, an average value is obtained to obtain the buried depth of the buried electrode;

s207: and according to the buried depth of the buried electrode, carrying out buried configuration on the buried electrode.

7. The method according to claim 1, wherein S3 comprises:

s301: capturing the received communication signal by adopting a method of adding a longer synchronous head to obtain a captured signal;

s302: down-sampling the captured signal to obtain a bearer communication signal;

s303: based on a carrier communication signal, acquiring a spread spectrum signal with a chip length of L, carrying out FFT (fast Fourier transform), and multiplying the spread spectrum signal by a frequency domain value of an original PN (pseudo-noise) code to obtain a first transform sequence;

s304: performing IFFT transformation on the first transformation sequence to obtain a sequence with the length of L, and despreading the load-bearing communication signal according to the position of the sequence peak value to obtain a despread signal;

s305: and RS decoding the despread signal to obtain target information.

8. The method for through-the-earth communication based on distance sensing according to claim 1, further comprising S4, suppressing communication interference of through-the-earth communication signals:

s401: intercepting the received through-the-earth communication signals according to preset points to obtain intercepted through-the-earth communication signals;

s402: filtering the intercepted through-the-earth communication signal by a high-order filter by adopting a multiphase filtering technology;

s403: performing FFT calculation on the communication signal after filtering processing to obtain an interference signal frequency higher than a preset threshold;

s404: and (3) performing time domain narrowband interference suppression by using the frequency value of the interference signal as an initial value by using a time domain adaptive notch filter.

9. The through-the-earth communication method based on distance induction according to claim 1, characterized by further comprising S5, detecting signal attenuation and compensating;

s501: setting a fixed potential difference value between a ground penetrating communication signal receiving end and a transmitting end under the condition of normal attenuation;

s502: measuring a potential difference value generated after a receiving end receives a through-the-earth communication signal, and calculating a first difference value between the potential difference value and a fixed potential difference value;

s503: determining the attenuation compensation amount corresponding to the first difference value according to a preset magnitude comparison table of the attenuation compensation amount and the absolute value of the first difference value;

s504: when the first difference is a positive value, performing increasing operation according to the attenuation compensation amount; and when the first difference value is a negative value, performing reduction operation according to the attenuation compensation amount.

10. A through-the-earth communication device based on distance sensing, comprising:

the through-the-earth communication signal acquisition module is used for acquiring target information to be transmitted and converting the target information into through-the-earth communication signals;

the ground penetrating communication device setting module is used for configuring a signal sending electrode pair and a shielding electrode pair based on a plurality of preset pairs of buried electrodes; the signal transmitting electrode pairs form a communication electric field through voltage change between the electrode pairs and are used for transmitting ground penetrating communication signals; the communication electric field bears the through-the-earth communication signal; the shielding electrode pair structure shields an electric field;

and the through-ground communication signal receiving module is used for receiving the through-ground communication signal by using the through-ground signal receiving device and converting the through-ground communication signal into target information.

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