High-speed communication method and system for perforation of single-core cable

Abstract

The invention belongs to the technical field of oil and gas well perforation, and relates to a high-speed communication method and system for single-core cable perforation. The method comprises the following steps: performing low-frequency modulation on underground perforation data; performing high-frequency modulation on underground logging data; synthesizing carrier signals; the driving power of the carrier synthesis signal is amplified, so that the carrier synthesis signal is transmitted to the ground end on the single-core cable; the ground terminal carries out carrier signal conditioning on the carrier synthesis signal and then carries out amplification processing; carrying out carrier signal separation, and respectively outputting a low-frequency modulation signal and a high-frequency modulation signal; and outputting perforation data and logging data. According to the invention, perforation signals and underground logging data can be transmitted on the single-core cable at the same time, and the exploitation efficiency of an oil-gas well is improved; according to the single-core cable perforation communication system, continuity and low delay characteristics of perforation operation signals are kept, discrete data can be selectively transmitted, the efficiency of single-core cable perforation communication is improved, and mutual influence of perforation or logging communication faults is effectively avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas well perforation, and in particular, relates to a high-speed communication method and system for single-core cable perforation. Background Art

[0002] Unconventional oil and gas reservoirs such as shale gas and tight oil and gas are adsorbed or free in mudstone interlayers rich in organic matter. During the development process, multi-stage cluster perforation and bridge plug combination is currently the most widely used development method at home and abroad. The cable conveys the pipe string and ignites and seals the multi-stage detonators and bridge plugs in sequence, and the multi-stage graded controlled perforation penetrates the casing and the formation, providing the prerequisite for staged fracturing operations.

[0003] Perforating oil and gas wells requires real-time collection of perforating data downhole. Existing perforating communication methods are mainly based on the low-speed transmission of perforating operation control instructions, while digital communication methods suitable for logging data collection are prone to data loss, which has a great impact on perforating operations with high real-time requirements.

[0004] The prior art discloses a high-speed data transmission system based on a single-core logging cable, including a ground part and a downhole part connected by a single-core logging cable, wherein the downlink channel of the high-speed data transmission system is formed by sequentially connecting a ground user data interface, an AMI encoder, a ground analog front end, a single-core logging cable, a downhole analog front end, an AMI decoder and a downhole user data interface, and the uplink channel is formed by sequentially connecting a downhole user data interface, an OFDM modulator, a downhole analog front end, a single-core logging cable, a ground analog front end, an OFDM demodulator and a ground user data interface. The system is only used for production logging, and does not mention how to stably transmit perforating operation data.

[0005] In summary, the problem of high-speed transmission of logging data while stably transmitting downhole perforation data during perforation operations is a difficult problem that needs to be solved. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a high-speed communication method and system for single-core cable perforating.

[0007] In a first aspect, the present invention provides a high-speed communication method for single-core cable perforation, comprising:

[0008] The downhole end loads the downhole perforation data into the low frequency band of the single-core cable channel by low frequency modulation to obtain a low frequency modulation signal;

[0009] The downhole end divides the medium and high frequency bands of the single-core cable channel into multiple orthogonal channels, modulates the downhole logging data to the medium and high frequency bands of the single-core cable channel, and obtains a high-frequency modulated signal;

[0010] The downhole end synthesizes the carrier signal of the low-frequency modulation signal and the high-frequency modulation signal to form a carrier synthesis signal transmitted on a single-core cable;

[0011] The downhole end amplifies the driving power of the carrier synthesis signal, so that the carrier synthesis signal is transmitted to the surface end on the single-core cable;

[0012] The ground terminal amplifies the received carrier composite signal after carrier signal conditioning;

[0013] The ground terminal separates the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier composite signal, and outputs the low-frequency modulation signal and the high-frequency modulation signal respectively;

[0014] The ground end performs envelope detection and demodulation on the low-frequency modulation signal and then outputs the perforation data through power amplification drive, and outputs the logging data after filtering, synchronization and decoding the high-frequency modulation signal.

[0015] In a second aspect, the present invention provides a high-speed communication system for single-core cable perforation, comprising a downhole end, a single-core cable and a ground end; the downhole end comprises a low-frequency modulation unit, a high-frequency modulation unit, a carrier signal synthesis unit and a carrier signal driving unit; the ground end comprises a carrier signal conditioning unit, a carrier signal separation unit, a low-frequency demodulation unit and a high-frequency demodulation unit;

[0016] A low-frequency modulation unit is used to load the downhole perforation data into the low-frequency band of the single-core cable channel by low-frequency modulation to obtain a low-frequency modulation signal;

[0017] A high-frequency modulation unit is used to divide the medium and high frequency bands of the single-core cable channel into a plurality of orthogonal channels, and modulate the downhole logging data into the medium and high frequency bands of the single-core cable channel to obtain a high-frequency modulation signal;

[0018] The carrier signal synthesis unit is used to synthesize the carrier signals of the low-frequency modulation signal and the high-frequency modulation signal at the downhole end to form a carrier synthesis signal transmitted on the single-core cable;

[0019] The carrier signal driving unit is used to amplify the driving power of the carrier synthesis signal so that the carrier synthesis signal is transmitted to the ground end on the single-core cable;

[0020] The carrier signal conditioning unit is used to amplify the received carrier synthesis signal after carrier signal conditioning;

[0021] The carrier signal separation unit is used to separate the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier composite signal, and output the low-frequency modulation signal and the high-frequency modulation signal respectively;

[0022] A low-frequency demodulation unit is used to perform envelope detection demodulation on the low-frequency modulation signal and then drive the output of perforation data through power amplification;

[0023] The high frequency demodulation unit is used to filter, synchronize and decode the high frequency modulation signal and then output the logging data.

[0024] Based on the above technical solution, the present invention can also be improved as follows.

[0025] Furthermore, a digital processor is used to modulate the downhole logging data to the medium and high frequency bands of the single-core cable channel to obtain a high-frequency modulated signal. The logging data is mapped to a constellation diagram and then inverse Fourier transformed to generate information code elements. A cyclic prefix with a length that is a set proportion of the information code element is added to the front end of the information code element. The information code element is multiplied by the cosine and sine components of the carrier to generate an in-phase component and an orthogonal component. The in-phase component and the orthogonal component carrier are synthesized to form a digital carrier signal. The carrier signal data frames are separated by high and low levels to form a frame interval.

[0026] Furthermore, the low-frequency modulation signal and the high-frequency modulation signal are synthesized at the downhole end, and filtered through a bandpass filter to form a carrier synthesis signal transmitted on a single-core cable.

[0027] Furthermore, the ground end performs carrier signal separation on the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier synthesis signal. The low-frequency modulation signal after carrier signal separation is output as a low-frequency modulation signal through a low-pass filter, and the high-frequency modulation signal after carrier signal separation is filtered through a high-pass filter and output as a high-frequency modulation signal.

[0028] Furthermore, the high-frequency modulated signal is multiplied with the cosine and sine components of the carrier signal to generate an in-phase component and an orthogonal component. The in-phase component and the orthogonal component are combined to form information codeword frame data. The information codeword is located to the cyclic prefix in the frame data through high and low levels. The cyclic prefix is ​​removed and then Fourier transformed to obtain a constellation diagram. The constellation diagram is sampled and judged to restore the original downhole logging data.

[0029] Furthermore, when the received carrier composite signal is amplified after carrier signal conditioning, the gain multiple is automatically adjusted by comparing the amplitude of the carrier composite signal after signal conditioning with the set amplitude value to keep the difference between the amplitude of the carrier composite signal after signal conditioning and the set amplitude value within the set range.

[0030] Furthermore, the low-frequency modulation unit includes a first transformer, a first diode, a second diode, a digital processor, a second transformer and a first resistor; the input end of the first transformer is electrically signal connected to the input end of the low-frequency modulation unit; the first output end of the first transformer is electrically signal connected to the first input end of the second transformer through the first diode; the second output end of the first transformer is electrically signal connected to the second input end of the second transformer through the second diode; the first output end of the digital processor is electrically signal connected to the third output end of the first transformer; the second output end of the digital processor is electrically signal connected to the third input end of the second transformer; the first output end of the second transformer is electrically signal connected to the first end of the first resistor and the first output end of the low-frequency modulation unit; the second output end of the second transformer is electrically signal connected to the second end of the first resistor and the second output end of the low-frequency modulation unit.

[0031] Furthermore, the low-frequency demodulation unit includes a third diode, a first capacitor, a second resistor, an envelope detector and a power amplifier; the anode of the third diode is electrically connected to the first input terminal of the low-frequency demodulation unit; the cathode of the third diode is electrically connected to the first end of the first capacitor, the first end of the second resistor and the first input terminal of the envelope detector; the second input terminal of the low-frequency demodulation unit is electrically connected to the second end of the first capacitor, the second end of the second resistor and the second input terminal of the envelope detector; the output terminal of the envelope detector is electrically connected to the input terminal of the power amplifier; and the output terminal of the power amplifier is electrically connected to the output terminal of the low-frequency demodulation unit.

[0032] The beneficial effects of the present invention are:

[0033] (1) The present invention can meet the requirements of compatible transmission of perforation data and downhole logging data on a single-core cable, thereby improving the production efficiency of oil and gas wells;

[0034] (2) The present invention can realize the continuity and low-latency characteristics of perforating operation signals, and can selectively transmit discrete logging data at high speed, thereby increasing the efficiency of single-core cable perforating communication;

[0035] (3) Placing the perforating operation signal and the logging data signal on different frequency bands effectively avoids the mutual influence of perforating or logging communication failures, reduces the risk of propagation of single-core cable communication failures, and improves the safety, reliability and stability of oil and gas well perforating operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of a high-speed communication method for single-core cable perforating provided in Example 1 of the present invention;

[0037] Figure 2 A communication flow chart of a high-speed communication method for single-core cable perforating provided in Embodiment 1 of the present invention;

[0038] Figure 3 A system block diagram of a high-speed communication system for single-core cable perforating provided in Embodiment 2 of the present invention;

[0039] Figure 4 It is a flowchart of the downhole logging data modulation process;

[0040] Figure 5 It is a flowchart of the demodulation process of downhole logging data;

[0041] Figure 6 It is the circuit schematic diagram of the low frequency modulation unit;

[0042] Figure 7 This is the circuit schematic diagram of the low-frequency demodulation unit.

[0043] In the figure: D1-first diode; D2-second diode; D3-third diode; T1-first transformer; T2-second transformer; R1-first resistor; R2-second resistor; C1-first capacitor; U1-digital processor; U2-envelope detector; U3-power amplifier. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0045] Example 1

[0046] As an example, Figure 1 As shown, in order to solve the above technical problems, this embodiment provides a high-speed communication method for single-core cable perforating, comprising:

[0047] The downhole end loads the downhole perforation data into the low frequency band of the single-core cable channel by low frequency modulation to obtain a low frequency modulation signal;

[0048] The downhole end divides the medium and high frequency bands of the single-core cable channel into multiple orthogonal channels, modulates the downhole logging data to the medium and high frequency bands of the single-core cable channel, and obtains a high-frequency modulated signal;

[0049] The downhole end synthesizes the carrier signal of the low-frequency modulation signal and the high-frequency modulation signal to form a carrier synthesis signal transmitted on a single-core cable;

[0050] The downhole end amplifies the driving power of the carrier synthesis signal, so that the carrier synthesis signal is transmitted to the surface end on the single-core cable;

[0051] The ground terminal amplifies the received carrier composite signal after carrier signal conditioning;

[0052] The ground terminal separates the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier composite signal, and outputs the low-frequency modulation signal and the high-frequency modulation signal respectively;

[0053] The ground end performs envelope detection and demodulation on the low-frequency modulation signal and then outputs the perforation data through power amplification drive, and outputs the logging data after filtering, synchronization and decoding the high-frequency modulation signal.

[0054] As attached Figure 2 Shown is a communication flow chart of the high-speed communication method for single-core cable perforating.

[0055] In actual application, low-frequency modulation is used for downhole perforating data, such as electronic detonator control data of downhole perforating, to ensure the continuity of the perforating operation signal while maintaining the same signal characteristics as the original perforating operation signal.

[0056] Low-frequency modulation occupies the low-frequency band of the single-core cable channel, and high-frequency modulation occupies the high-frequency band of the single-core cable channel. When the single-core cable channel in some oil and gas wells is severely limited, the reliable transmission of perforation operation signals can be guaranteed. Decoupling modulation using low-frequency modulation and high-frequency modulation for downhole perforation operation data and downhole logging signal discrete data can reduce the complexity and power consumption of the downhole communication system and improve the reliability of the system's high temperature resistance in the well.

[0057] The downhole perforating operation data and logging data are respectively modulated at low frequency and high frequency to form a carrier synthesis signal suitable for transmission on a single-core cable, which can be transmitted on the single-core cable at the same time to achieve the functional integration of perforating operation and logging operation.

[0058] The driving power of the carrier synthesis signal is amplified at the downhole end. By amplifying the driving power of the carrier signal, the carrier synthesis signal can be transmitted to the carrier conditioning module on the ground over a long distance single-core cable.

[0059] Optional, as attached Figure 4 The downhole logging data modulation process flow chart shown in the figure uses a digital processor to modulate the downhole logging data to the medium and high frequency bands of the single-core cable channel to obtain a high-frequency modulation signal, and then performs inverse Fourier transform on the logging data after constellation mapping to generate information code elements, and adds a cyclic prefix with a length that is a set ratio of the information code element to the front end of the information code element, multiplies the information code element with the cosine and sine components of the carrier to generate an in-phase component and an orthogonal component, and the in-phase component and the orthogonal component carrier are synthesized to form a digital carrier signal, and the carrier signal data frames are separated by high and low levels to form a frame interval.

[0060] As an optional implementation, high-frequency modulation uses a digital processor to map the logging data to a 16QAM (16Quadrature Amplitude Modulation, 16 orthogonal amplitude modulation) constellation diagram, and then perform inverse Fourier transform to generate information code elements. A cyclic prefix with a length of 1 / 4 of the information code element is added to the front end of the information code element, and the information code element is multiplied by the cosine and sine components of the carrier to generate an in-phase component and an orthogonal component. The in-phase component and the orthogonal component carrier are synthesized to form a digital carrier signal, and the carrier signal data frames are separated by high and low levels to form a frame interval.

[0061] Optionally, the downhole end synthesizes the low-frequency modulation signal and the high-frequency modulation signal, and filters them through a bandpass filter to form a carrier synthesis signal transmitted on a single-core cable.

[0062] Optionally, the ground end performs carrier signal separation on the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier synthesis signal. The low-frequency modulation signal after carrier signal separation is output as a low-frequency modulation signal through a low-pass filter, and the high-frequency modulation signal after carrier signal separation is filtered through a high-pass filter and then output as a high-frequency modulation signal.

[0063] Optional, as attached Figure 5 The flowchart of the demodulation process of downhole logging data shown in the figure multiplies the high-frequency modulation signal with the cosine and sine components of the carrier signal to generate in-phase components and quadrature components. The in-phase components and quadrature components are combined to form information codeword frame data. The information codeword is located to the cyclic prefix through high and low levels in the frame data. The cyclic prefix is ​​removed and then Fourier transformed to obtain a constellation diagram. The original downhole logging data is restored to the constellation diagram through sampling and judgment.

[0064] Optionally, when the received carrier composite signal is amplified after carrier signal conditioning, the gain multiple is automatically adjusted by comparing the amplitude of the carrier composite signal after signal conditioning with the set amplitude value to keep the difference between the amplitude of the carrier composite signal after signal conditioning and the set amplitude value within a set range.

[0065] By comparing the amplitude of the carrier synthesis signal with the set amplitude value, the amplification factor of the carrier conditioning module is automatically adjusted to achieve automatic gain control.

[0066] This method has the following advantages:

[0067] (1) The present invention can meet the requirements of compatible transmission of perforation data and downhole logging data on a single-core cable, thereby improving the production efficiency of oil and gas wells;

[0068] (2) This method can achieve the continuity and low latency characteristics of the perforating operation signal, and can selectively transmit the discrete data of logging at high speed, thereby increasing the efficiency of single-core cable perforating communication;

[0069] (3) Placing perforating operation data and logging high-frequency data signals on different frequency bands effectively avoids the mutual influence of perforating or logging communication failures, reduces the risk of single-core cable communication failure propagation, and improves the safety, reliability and stability of oil and gas well perforating operations;

[0070] (4) Using discrete devices to complete low-frequency signal modulation of downhole perforation data can reduce the complexity and power consumption of the downhole communication system and improve the reliability of the system in high temperature resistance underground;

[0071] (5) This method has a feedback-based gain adjustment function, which improves the adaptability and robustness of high-speed communication in different well conditions and single-core cables.

[0072] Example 2

[0073] Based on the same principle as the method shown in Example 1 of the present invention, as shown in the attached Figure 3 As shown, an embodiment of the present invention further provides a high-speed communication system for single-core cable perforating, comprising a downhole end, a single-core cable and a ground end; the downhole end comprises a low-frequency modulation unit, a high-frequency modulation unit, a carrier signal synthesis unit and a carrier signal driving unit; the ground end comprises a carrier signal conditioning unit, a carrier signal separation unit, a low-frequency demodulation unit and a high-frequency demodulation unit;

[0074] A low-frequency modulation unit is used to load the downhole perforation data into the low-frequency band of the single-core cable channel by low-frequency modulation to obtain a low-frequency modulation signal;

[0075] A high-frequency modulation unit is used to divide the medium and high frequency bands of the single-core cable channel into a plurality of orthogonal channels, and modulate the downhole logging data into the medium and high frequency bands of the single-core cable channel to obtain a high-frequency modulation signal;

[0076] The carrier signal synthesis unit is used to synthesize the carrier signals of the low-frequency modulation signal and the high-frequency modulation signal at the downhole end to form a carrier synthesis signal transmitted on the single-core cable;

[0077] The carrier signal driving unit is used to amplify the driving power of the carrier synthesis signal so that the carrier synthesis signal is transmitted to the ground end on the single-core cable;

[0078] The carrier signal conditioning unit is used to amplify the received carrier synthesis signal after carrier signal conditioning;

[0079] The carrier signal separation unit is used to separate the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier composite signal, and output the low-frequency modulation signal and the high-frequency modulation signal respectively;

[0080] A low-frequency demodulation unit is used to perform envelope detection demodulation on the low-frequency modulation signal and then drive the output of perforation data through power amplification;

[0081] The high frequency demodulation unit is used to filter, synchronize and decode the high frequency modulation signal and then output the logging data.

[0082] Optional, as attached Figure 6 As shown, the low-frequency modulation unit includes a first transformer T1, a first diode D1, a second diode D2, a digital processor U1, a second transformer T2 and a first resistor R1; the input end of the first transformer T1 is electrically connected to the input end of the low-frequency modulation unit; the first output end of the first transformer T1 is electrically connected to the first input end of the second transformer T2 through the first diode D1; the second output end of the first transformer T1 is electrically connected to the second input end of the second transformer T2 through the second diode D2; the first output end of the digital processor U1 is electrically connected to the third output end of the first transformer D1; the second output end of the digital processor U1 is electrically connected to the third input end of the second transformer T2; the first output end of the second transformer T2 is electrically connected to the first end of the first resistor R1 and the first output end of the low-frequency modulation unit; the second output end of the second transformer T2 is electrically connected to the second end of the first resistor R1 and the second output end of the low-frequency modulation unit.

[0083] The PWM control signal generated by the digital processor controls the conduction of the second diode to generate a carrier signal. The carrier signal modulates the perforation signal coupled by the first transformer T1, and is coupled and output by the second transformer T2 to generate a modulation signal on the first resistor R1. The downhole perforation signal is modulated at a low frequency, which is simple and reliable and suitable for high-temperature downhole environments.

[0084] Optional, as attached Figure 7 As shown, the low-frequency demodulation unit includes a third diode D3, a first capacitor C1, a second resistor R2, an envelope detector U2 and a power amplifier U3; the anode of the third diode D3 is electrically signal connected to the first input terminal of the low-frequency demodulation unit; the cathode of the third diode D3 is electrically signal connected to the first end of the first capacitor C1, the first end of the second resistor R2 and the first input terminal of the envelope detector U2; the second input terminal of the low-frequency demodulation unit is electrically signal connected to the second end of the first capacitor C1, the second end of the second resistor R2 and the second input terminal of the envelope detector U2; the output terminal of the envelope detector U2 is electrically signal connected to the input terminal of the power amplifier U3; and the output terminal of the power amplifier U3 is electrically signal connected to the output terminal of the low-frequency demodulation unit.

[0085] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-speed communication method for single-core cable perforation, characterized in that: include: The downhole end loads the downhole perforation data into the low frequency band of the single-core cable channel by low frequency modulation to obtain a low frequency modulation signal; The downhole end divides the medium and high frequency bands of the single-core cable channel into multiple orthogonal channels, modulates the downhole logging data to the medium and high frequency bands of the single-core cable channel, and obtains a high-frequency modulated signal; The downhole end performs carrier signal synthesis on the low-frequency modulation signal and the high-frequency modulation signal to form a carrier synthesis signal transmitted on a single-core cable; The downhole end amplifies the driving power of the carrier synthesis signal, so that the carrier synthesis signal is transmitted to the surface end on the single-core cable; The ground terminal amplifies the received carrier composite signal after carrier signal conditioning; The ground terminal separates the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier composite signal, and outputs the low-frequency modulation signal and the high-frequency modulation signal respectively; The ground end performs envelope detection and demodulation on the low-frequency modulation signal and then drives the power amplifier to output the perforation data, and filters, synchronizes and decodes the high-frequency modulation signal and then outputs the logging data.

2. A high-speed communication method for single-core cable perforation according to claim 1, characterized in that: A digital processor is used to modulate the downhole logging data to the medium and high frequency bands of the single-core cable channel to obtain a high-frequency modulated signal. The logging data is mapped to a constellation diagram and then inverse Fourier transform is performed to generate information code elements. A cyclic prefix with a length that is a set proportion of the information code element is added to the front end of the information code element. The information code element is multiplied by the cosine and sine components of the carrier to generate an in-phase component and an orthogonal component. The in-phase component and the orthogonal component carrier are synthesized to form a digital carrier signal. The carrier signal data frames are separated by high and low levels to form a frame interval.

3. A high-speed communication method for single-core cable perforation according to claim 1, characterized in that: The low-frequency modulation signal and the high-frequency modulation signal are synthesized at the downhole end, and filtered through a bandpass filter to form a carrier synthesis signal transmitted on a single-core cable.

4. A high-speed communication method for single-core cable perforation according to claim 1, characterized in that: The ground end performs carrier signal separation on the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier synthesis signal. The low-frequency modulation signal after carrier signal separation is output as a low-frequency modulation signal through a low-pass filter, and the high-frequency modulation signal after carrier signal separation is filtered through a high-pass filter and output as a high-frequency modulation signal.

5. A high-speed communication method for single-core cable perforation according to claim 1, characterized in that: The high-frequency modulated signal is multiplied by the cosine and sine components of the carrier signal to generate in-phase components and quadrature components. The in-phase components and quadrature components are combined to form information codeword frame data. The information codeword is located to the cyclic prefix through high and low levels in the frame data. The cyclic prefix is ​​removed and Fourier transform is performed to obtain a constellation diagram; the constellation diagram is sampled and judged to restore the original downhole logging data.

6. A high-speed communication method for single-core cable perforation according to claim 1, characterized in that: When the received carrier composite signal is amplified after carrier signal conditioning, the gain multiple is automatically adjusted by comparing the amplitude of the carrier composite signal after signal conditioning with the set amplitude value to keep the difference between the amplitude of the carrier composite signal after signal conditioning and the set amplitude value within the set range.

7. A high-speed communication system for single-core cable perforation, characterized in that: It includes a downhole end, a single-core cable and a ground end; the downhole end includes a low-frequency modulation unit, a high-frequency modulation unit, a carrier signal synthesis unit and a carrier signal driving unit; the ground end includes a carrier signal conditioning unit, a carrier signal separation unit, a low-frequency demodulation unit and a high-frequency demodulation unit; A low-frequency modulation unit is used to load the downhole perforation data into the low-frequency band of the single-core cable channel by low-frequency modulation to obtain a low-frequency modulation signal; A high-frequency modulation unit is used to divide the medium and high frequency bands of the single-core cable channel into a plurality of orthogonal channels, and modulate the downhole logging data to the medium and high frequency bands of the single-core cable channel to obtain a high-frequency modulation signal; The carrier signal synthesis unit is used to synthesize the low-frequency modulation signal and the high-frequency modulation signal at the downhole end to form a carrier synthesis signal transmitted on the single-core cable; The carrier signal driving unit is used to amplify the driving power of the carrier synthesis signal so that the carrier synthesis signal is transmitted to the ground end on the single-core cable; The carrier signal conditioning unit is used to amplify the received carrier synthesis signal after carrier signal conditioning; The carrier signal separation unit is used to separate the low-frequency modulation signal and the high-frequency modulation signal in the amplified carrier composite signal, and output the low-frequency modulation signal and the high-frequency modulation signal respectively; A low-frequency demodulation unit is used to perform envelope detection demodulation on the low-frequency modulation signal and then drive the output of perforation data through power amplification; The high frequency demodulation unit is used to filter, synchronize and decode the high frequency modulation signal and then output the logging data.

8. A high-speed communication system for single-core cable perforating according to claim 7, characterized in that: The low-frequency modulation unit includes a first transformer, a first diode, a second diode, a digital processor, a second transformer and a first resistor; the input end of the first transformer is electrically connected to the input end of the low-frequency modulation unit; the first output end of the first transformer is electrically connected to the first input end of the second transformer through the first diode; the second output end of the first transformer is electrically connected to the second input end of the second transformer through the second diode; The first output terminal of the digital processor is electrically connected to the third output terminal of the first transformer; The second output terminal of the digital processor is electrically connected to the third input terminal of the second transformer; The first output terminal of the second transformer is electrically connected to the first end of the first resistor and the first output terminal of the low-frequency modulation unit; The second output end of the second transformer is electrically connected to the second end of the first resistor and the second output end of the low-frequency modulation unit.

9. A high-speed communication system for single-core cable perforating according to claim 7, characterized in that: The low-frequency demodulation unit includes a third diode, a first capacitor, a second resistor, an envelope detector and a power amplifier; the anode of the third diode is electrically connected to the first input terminal of the low-frequency demodulation unit; the cathode of the third diode is electrically connected to the first end of the first capacitor, the first end of the second resistor and the first input terminal of the envelope detector; the second input terminal of the low-frequency demodulation unit is electrically connected to the second end of the first capacitor, the second end of the second resistor and the second input terminal of the envelope detector; the output terminal of the envelope detector is electrically connected to the input terminal of the power amplifier; and the output terminal of the power amplifier is electrically connected to the output terminal of the low-frequency demodulation unit.

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