Low-disturbance self-calibration multi-channel multiplexed ocean electric field acquisition device
By designing a low-leakage multiplexing matrix and calibration channels, the signal contamination and deviation problems of the marine electric field acquisition device when expanding the channels were solved, realizing efficient and low-disturbance acquisition and calibration of multiple electric field signals, and improving signal quality and device reliability.
Patent Information
- Application Number
- CN202611392591.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-09-09
- Publication Date
- 2026-11-06
AI Technical Summary
When expanding the number of channels, existing marine electric field acquisition devices are prone to introducing switch-injected charge, residual charge of the multiplexed bus, crosstalk between channels, memory effect of the previous channel, and time deviation of each channel, which leads to a decrease in signal quality. Furthermore, after long-term deployment, channel bias and electrode status are difficult to identify.
By employing a low-leakage multiplexing matrix, multiplexed bus discharge unit, zero-point calibration channel, and reference calibration channel, online error estimation and correction are performed by sharing the same analog path. Combined with adaptive dwell time and channel health diagnosis, synchronous acquisition and calibration of multiple electric field signals are achieved.
It effectively reduces the contamination of microvolt-level marine electric field signals by channel switching transients, maintains the comparability and accuracy of signals, reduces the size and power consumption of the acquisition device, and supports the efficient acquisition of dozens of electric field signals.
Smart Images
Figure CN123046513A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of marine exploration and environmental monitoring technology, specifically relating to a low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device. Background Technology
[0002] Marine electric field measurements typically target weak, low-frequency signals ranging from 0.0001 Hz to 10 Hz. These signals are characterized by high electrode output impedance, small signal amplitude, and susceptibility to the combined effects of electrode polarization, cable leakage, changes in seawater conductivity, temperature drift, and transient switching within the acquisition chamber during long-term deployment. Traditional acquisition chambers employing independent ADC channels can ensure good synchronization and low noise, but the number of channels is limited by chip resources, chamber space, power consumption, and the number of watertight interfaces. Directly using analog multiplexed chips to expand channels introduces switch-injected charge, residual charge on the multiplexed bus, inter-channel crosstalk, memory effects from the previous channel, and channel-by-channel time skew.
[0003] Therefore, it is of great significance to suppress the additional errors caused by analog multiplexing to weak electric field signals while significantly expanding the number of channels, and to maintain the comparability of each electric field component within the same sampling frame. Summary of the Invention
[0004] This invention addresses the problems of limited channel quantity in existing marine electric field acquisition chambers, the tendency of ordinary multiplexing expansion to reduce the signal-to-noise ratio of weak signals, inconsistent sampling times of different channels, and difficulty in timely identification of channel offset and electrode status after long-term deployment. It proposes a low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device.
[0005] The technical solution adopted in this invention is as follows: A low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device includes an electric field acquisition chamber and a multi-channel multiplexing module chamber. The electric field acquisition chamber is electrically connected to a watertight connector, and the multi-channel multiplexing module chamber is electrically connected to a watertight connector. The electric field acquisition chamber and the multi-channel multiplexing module chamber are electrically connected via the watertight connector, and the multi-channel multiplexing module chamber is electrically connected to an external electrode array via the watertight connector. The electric field acquisition chamber includes an outer shell, an internal support frame, a PCB circuit board, and a lithium battery. The PCB circuit board includes a main control unit, an ADC, a data storage unit, a communication unit, and a power management unit. The multiplexer module includes a housing, an internal support frame, and a PCB circuit board. The PCB circuit board includes an input protection-high impedance isolation unit, a low leakage multiplexing matrix, a multiplexing bus discharge unit, a zero-point calibration channel, a reference calibration channel, and a low bias buffer filter unit.
[0006] Furthermore, the lithium battery in the electric field acquisition chamber is electrically connected to the main control unit, ADC, data storage unit, communication unit, power management unit, and low-leakage multiplexing matrix, respectively.
[0007] Furthermore, the input protection-high impedance isolation unit, low leakage multiplexing matrix, and low bias buffer filter unit are connected by electrical signals in sequence. The multiplexing bus discharge unit, zero-point calibration channel, reference calibration channel, and main control unit are connected by electrical signals to the low leakage multiplexing matrix. The ADC is connected by electrical signals to the main control unit and the low bias buffer filter unit, respectively.
[0008] Furthermore, the low-leakage multiplexing matrix includes multiple low-leakage multiplexed analog switches.
[0009] Furthermore, the analog differential lines, digital control lines, and power lines in the watertight connector of the electric field acquisition chamber and the watertight connector of the multi-channel multiplexing module are arranged in groups.
[0010] Furthermore, the zero-point calibration channel, the reference calibration channel, and the electrode channels of the external electrode array share the same low-leakage multiplexing matrix, the same multiplexing bus discharge unit, and the same ADC.
[0011] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. This invention relies on a low-leakage multiplexing matrix and a multiplexing bus discharge unit to effectively reduce the contamination of microvolt-level marine electric field signals by channel switching transients.
[0012] 2. This invention achieves online estimation and correction of multiplexing path error by sharing the same simulation path with the target electrode channel and the zero-point calibration channel and reference calibration channel.
[0013] 3. This invention enables the identification and compensation of electrode polarization, leakage current and contact abnormalities during long-term deployment through adaptive dwell time and channel health diagnosis. 4. This invention enables multi-channel time-division sampling data to be used for electric field array, spatial gradient, and multi-dimensional component analysis through frame synchronization and timestamp reconstruction; 5. This invention enables the acquisition of dozens of electric field signals without stacking a large number of ADC chips, reducing the size, power consumption, and PCB circuit design complexity of the acquisition chamber. Attached Figure Description
[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic diagram of the electric field acquisition chamber of the present invention; Figure 2 This is a top view of the internal structure of the electric field acquisition chamber of the present invention; Figure 3 This is a schematic diagram of the structure of the multi-channel multiplexing module compartment of the present invention; Figure 4 This is a top view of the internal structure of the multi-channel multiplexing module compartment of the present invention; Figure 5 This is a block diagram of the low-disturbance self-calibration multiplexing acquisition link of the present invention. Figure 6 This is a timing diagram of a low-disturbance multiplexing sampling frame of the present invention.
[0015] The markings in the diagram are: 1-Watertight connector for the electric field acquisition chamber; 2-Internal support for the electric field acquisition chamber; 3-Outer shell of the electric field acquisition chamber; 4-Watertight connector for the multi-channel multiplexing module chamber; 5-Internal support for the multi-channel multiplexing module chamber; 6-Outer shell of the multi-channel multiplexing module chamber; 7-PCB circuit board for the electric field acquisition chamber; 8-Lithium battery for the electric field acquisition chamber; 9-PCB circuit board for the multi-channel multiplexing module chamber. Detailed Implementation
[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0017] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.
[0018] It should be noted that the labels and letters in the following figures represent similar items, therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0019] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only used for the purpose of simplifying the description of this invention and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0020] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0021] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0022] A low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device includes an electric field acquisition chamber and a multi-channel multiplexing module chamber. The electric field acquisition chamber is electrically connected to a watertight connector, and the multi-channel multiplexing module chamber is electrically connected to a watertight connector. The electric field acquisition chamber and the multi-channel multiplexing module chamber are electrically connected via the watertight connector, and the multi-channel multiplexing module chamber is electrically connected to an external electrode array via the watertight connector. The electric field acquisition chamber includes an outer shell, an internal support frame, a PCB circuit board, and a lithium battery. The PCB circuit board includes a main control unit, an ADC, a data storage unit, a communication unit, and a power management unit. The multiplexer module includes a housing, an internal support frame, and a PCB circuit board. The PCB circuit board includes an input protection-high impedance isolation unit, a low leakage multiplexing matrix, a multiplexing bus discharge unit, a zero-point calibration channel, a reference calibration channel, and a low bias buffer filter unit.
[0023] The lithium battery in the electric field acquisition chamber is electrically connected to the main control unit, ADC, data storage unit, communication unit, power management unit, and low-leakage multiplexing matrix.
[0024] The input protection-high impedance isolation unit, low leakage multiplexing matrix, and low bias buffer filter unit are connected by electrical signals in sequence. The multiplexing bus discharge unit, zero-point calibration channel, reference calibration channel, and main control unit are connected by electrical signals to the low leakage multiplexing matrix. The ADC is connected by electrical signals to the main control unit and the low bias buffer filter unit respectively.
[0025] The low-leakage multiplexing matrix includes multiple low-leakage multiplexed analog switches.
[0026] The analog differential lines, digital control lines, and power lines in the watertight connectors of the electric field acquisition chamber and the multi-channel multiplexing module are arranged in groups.
[0027] The zero-point calibration channel, the reference calibration channel, and the electrode channels of the external electrode array share the same low-leakage multiplexing matrix, the same multiplexing bus discharge unit, and the same ADC.
[0028] Specifically, the multiplexing matrix in the multi-channel multiplexing module does not directly perform ordinary "gating-sampling" operations. Instead, it performs switching control, multiplexing bus reset, charge discharge, and stabilization waiting between adjacent channels. The multiplexing bus discharge unit shorts the multiplexing common terminal to the analog reference potential or low-noise common-mode potential, and then selects the target channel after discharge to eliminate the residual charge on the bus capacitor of the previous channel.
[0029] The signal lines, reference lines, and shielding / guard ring lines of each electrode channel are arranged in groups and switched synchronously by the same control sequence during multiplexing, ensuring that the leakage current, parasitic capacitance, and shielding status of the selected channels remain consistent. This structure addresses the multiplexing errors of high-impedance, low-frequency electrode signals in seawater environments, rather than channel expansion in general electronic systems.
[0030] The multiplexing matrix is configured with at least one zero-point calibration channel and at least one reference calibration channel. The zero-point calibration channel shorts the ADC input path to the analog reference ground via a low-noise analog switch, and the reference calibration channel is connected to a stable reference voltage or an equivalent weak electric field analog source. The zero-point, reference, and electrode-under-test signals share the same multiplexing matrix, the same differential bus, and the same ADC input path.
[0031] The main control unit inserts a sequence of "zero sample - target channel sample - reference sample" or "zero sample - multiple target channel samples - reference sample" into each sampling frame. It uses the zero and reference data obtained along the same path to estimate the switch injection offset, ADC zero drift, path gain drift and temperature-related errors, and corrects the target channel data.
[0032] The electric field acquisition chamber dynamically adjusts the stabilization waiting time and effective sampling count after the target channel is selected based on the electrode impedance of each channel, the noise level of the previous frame, the zero-point recovery time, and the reference channel deviation. For channels with high impedance, long stabilization time, or abnormal drift, the main control unit extends the dwell time, increases the average number of samplings, or marks them as channels to be retested; for stable channels, the dwell time is shortened to improve the overall frame refresh rate.
[0033] During ineffective sampling intervals, the multiplexed module can detect open circuits, short circuits, insulation degradation, and leakage conditions of electrodes via calibration resistors, minute test currents, or high-resistance voltage divider networks. This diagnostic process is executed out of time with normal signal acquisition, preventing diagnostic excitation from entering the effective electric field data and achieving adaptive dwell time and channel health diagnosis.
[0034] The electric field acquisition module sends a unified frame synchronization signal to the multi-channel multiplexing module. The multi-channel multiplexing module writes the channel number, frame number, and timestamp each time a channel is selected and a valid sample is taken. Based on the timestamp, channel table, and low-frequency electric field variation characteristics, the main control unit reconstructs the multi-channel data acquired in a time-division multiplexing manner within a frame into electric field array data for the same observation time.
[0035] For channel groups that require calculation of spatial gradients, directional components, or multi-electrode differentials, the main control unit adopts an interleaved sampling sequence so that electrode pairs within the same group complete sampling within the shortest time window; when necessary, it uses interpolation compensation based on data from preceding and following frames within the same group, thereby reducing the time deviation between channels caused by ordinary time-division multiplexing.
[0036] The lithium battery inside the electric field acquisition chamber supplies power to the analog multiplexing, ADC, and digital control circuits via isolated voltage regulation and a low-noise LDO, respectively. The analog ground, digital ground, and chamber shield ground are connected at the ADC preamplifier or a designated single point. The analog differential lines, digital control lines, and power lines in the watertight connectors are arranged in groups. The analog differential lines preferably use shielded twisted-pair or coaxial structures, and the shielding layer is driven by a low-impedance reference point or grounded at one end.
[0037] The aforementioned compartmentalized power supply, single-point reference, and shielded ring structure prevents the channel selection pulse, digital control edge, and cross-compartment power supply ripple of the multi-channel multiplexing module from coupling to the weak electric field simulation path.
[0038] Example 1 The electric field acquisition chamber and the multiplexing module chamber are two independent pressure-resistant chambers. Both chambers are provided with pressure and waterproof protection and are electrically interconnected underwater via watertight connectors. The multiplexing module chamber is located on the side closer to the external electrode array to shorten the unshielded transmission distance of the signal before it enters the multiplexing matrix; the electric field acquisition chamber houses the main control unit, high-precision ADC, data storage, and power management unit.
[0039] The external electrode array includes multiple sets of silver / silver chloride non-polarized electrodes, forming 32 differential electric field components or 64 single-ended electrode signals. The PCB board of the multi-channel multiplexing module compartment is equipped with four ADG706 or equivalent low-leakage analog multiplexers to form a multiplexing matrix of up to 64 channels. The PCB board of the electric field acquisition compartment is equipped with three CS5532 or equivalent high-precision ΔΣ ADCs to receive the multiplexed differential analog signals.
[0040] The multichannel multiplexing module includes an outer shell, watertight connectors, internal support, PCB circuit board, input protection-high impedance isolation unit, low leakage multiplexing matrix, multiplexing bus discharge unit, zero-point calibration channel, reference calibration channel, and low bias buffer filter unit.
[0041] Input protection – The high-impedance isolation unit limits the effects of surges, abrupt electrode polarization changes, and electrostatic discharge on the multiplexing matrix, and reduces leakage current at high-impedance nodes through guard rings or shielding layers. The low-leakage multiplexing matrix receives channel selection commands from the master control unit for switching. The multiplexing bus discharge unit resets the common analog bus to the analog reference potential before each channel switch, reducing residual charge from the previous channel.
[0042] The zero-point calibration channel and the reference calibration channel are not acquired through independent ADCs, but share the same multiplexing matrix, the same analog bus and the same ADC input with the electrode under test channel, so that the calibration sample can reflect the switch on-resistance, leakage current, bias and temperature drift in the real sampling path.
[0043] The electric field acquisition chamber includes an outer shell, watertight connectors, internal support, PCB circuit board, lithium battery, main control unit, high-precision ADC, data storage unit, communication unit, and power management unit. The main control unit generates a unified sampling frame clock, sends the channel table, reset duration, dwell time, and effective sampling count to the multi-channel multiplexing module, and receives data output from the ADC.
[0044] The lithium battery powers the analog multiplexing matrix, ADC, main control unit, and communication unit respectively through isolated DC / DC converters and low-noise linear regulators. Analog ground and digital ground are isolated and connected through ferrite beads, resistors, or single-point connection structures to prevent the channel selection pulse from being coupled to the ADC input terminal via ground line return.
[0045] The low-disturbance multiplexing sampling process is as follows: Step S1: The main control unit starts the sampling frame, selects the zero-point calibration channel, and collects the zero-point offset sample of the current frame.
[0046] Step S2: The main control unit disconnects the current channel and drives the multiplexed bus discharge unit to return the multiplexed common terminal to the analog reference potential.
[0047] Step S3: The main control unit selects the target electrode channel according to the channel table and synchronously switches the signal corresponding to that channel.
[0048] Step S4: The system waits for a settling time that matches the channel impedance and bus capacitance, and discards the first or first few conversion results of the ADC during the settling time.
[0049] Step S5: The ADC acquires valid samples from the target channel, and the main control unit records the channel number, frame number, gating time, valid sampling time, and sampled value.
[0050] Step S6: Select the reference calibration channel at a preset interval to obtain a reference sample, which is used to estimate gain drift and path drift.
[0051] Step S7: Interleaved sampling is performed on related channels within the same spatial component or the same electrode group, and pseudo-synchronization reconstruction is performed based on timestamps.
[0052] Step S8: If the zero-point recovery time, reference deviation, noise variance, or impedance diagnosis result of a certain channel exceeds the threshold, the main control unit adjusts the dwell time of the next frame of that channel, or marks the channel as an abnormal channel and triggers a retest.
[0053] The same path calibration correction method is as follows: Let the first i In-frame channel k The original sample value is X k,i The zero-point channel samples before and after sampling in this channel are respectively Z pre,i and Z post,i The reference channel measured value is R meas,i The reference nominal value is R refThe main control unit can obtain the zero-point offset of the target channel sampling time through linear interpolation or low-pass estimation. Z i and according to R meas,i and R ref The ratio of the path gain coefficient is used to estimate the path gain coefficient. G i The corrected value is obtained as follows:
[0054] When the reference channel and the target channel are not acquired in the same subframe, the main control unit performs time interpolation based on the two consecutive samples from the reference channel to reduce the impact of slow temperature changes and ADC zero drift on the target channel. This correction method relies on the zero point, reference, and target signals sharing the same analog path, thus correcting multiplexing matrix path errors that cannot be covered by ordinary external calibration.
[0055] Adaptive dwell and channel diagnostics are as follows: The main control unit can maintain status parameters for each channel, including noise variance of the most recent few frames, the deviation between the first valid sample after stabilization and subsequent samples, zero-point recovery time, reference deviation, and electrode impedance estimate. Dwell time. T k It can be set as follows:
[0056] in, R k The equivalent impedance of the channel. C bus To reuse the bus equivalent capacitance. N k This is the recent noise assessment value for this channel, where a and b are empirical coefficients.
[0057] In channel diagnostic mode, the system can briefly connect the electrode channel under test to a calibration resistor or a weak test excitation to measure open circuit, short circuit, insulation degradation, or abnormal contact conditions. The diagnostic mode and the effective electric field acquisition mode operate at different times, and a bus reset and zero-point sampling are performed before effective sampling to avoid diagnostic residues affecting the observation data.
[0058] In addition, in this invention, the multiplexing matrix can be replaced by other low-leakage, low-charge-injection analog switch arrays instead of ADG706; the ADC can be replaced by other high-resolution, low-noise ΔΣ ADCs instead of CS5532; and the main control unit can be implemented by a microcontroller, FPGA, DSP, or SoC. The zero-point calibration channel can be implemented using simulated short circuits, equipotential short circuits, or connection to a low-noise reference ground; the reference calibration channel can be implemented using a stable voltage source, a resistor divider network, or an equivalent weak electric field simulation source. The external electrode array can either form differential electric field components according to fixed electrode pairs or dynamically reassemble electrode pairs through a channel table; after long-term deployment, the system can automatically avoid abnormal electrodes or rematch electrode groups based on electrode stability diagnostic results. Multiple multi-channel multiplexing module modules can be cascaded individually to expand to more than 64 channels. When cascaded, each multi-channel multiplexing module module uses the same frame synchronization signal and a unified timestamp format, and the electric field acquisition module performs cross-module pseudo-synchronization reconstruction.
[0059] The above description constitutes an embodiment of the present invention. The foregoing descriptions are preferred embodiments of the present invention. Unless there is a clear contradiction or a prerequisite for a particular preferred embodiment, the preferred embodiments can be arbitrarily combined and used. The embodiments and specific parameters described are merely for clearly illustrating the verification process of the invention and are not intended to limit the scope of patent protection of the present invention. The scope of patent protection of the present invention is still determined by its claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention should also be included within the scope of protection of the present invention.
Claims
1. A low-disturbance, self-calibrating, multi-channel multiplexed ocean electric field acquisition device, characterized in that, It includes an electric field acquisition chamber and a multi-channel multiplexing module chamber. The electric field acquisition chamber is electrically connected to a watertight connector (1). The multi-channel multiplexing module chamber is electrically connected to a watertight connector (4). The electric field acquisition chamber and the multi-channel multiplexing module chamber are electrically connected through the electric field acquisition chamber watertight connector (1). The multi-channel multiplexing module chamber is electrically connected to an external electrode array through the multi-channel multiplexing module chamber watertight connector (4). The electric field acquisition chamber includes an outer shell (3), an internal support (2) is provided inside the outer shell, a PCB circuit board (7) is installed on the internal support (2), a lithium battery (8) is provided inside the outer shell (3), and the PCB circuit board (7) is provided with a main control unit, an ADC, a data storage unit, a communication unit and a power management unit. The multiplexer module includes a multiplexer module housing (6), an internal support (5) for the multiplexer module is provided inside the housing (6), and a multiplexer module PCB circuit board (9) is installed on the internal support (5). The multiplexer module PCB circuit board (9) is provided with an input protection-high impedance isolation unit, a low leakage multiplexing matrix, a multiplexing bus discharge unit, a zero-point calibration channel, a reference calibration channel, and a low bias buffer filter unit.
2. The low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device according to claim 1, characterized in that, The lithium battery (8) of the electric field acquisition chamber is electrically connected to the main control unit, ADC, data storage unit, communication unit, power management unit and low leakage multiplexing matrix respectively.
3. A low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device according to claim 1, characterized in that, The input protection-high impedance isolation unit, low leakage multiplexing matrix, and low bias buffer filter unit are connected by electrical signals in sequence. The multiplexing bus discharge unit, zero-point calibration channel, reference calibration channel, main control unit, and low leakage multiplexing matrix are connected by electrical signals. The ADC is connected by electrical signals to the main control unit and the low bias buffer filter unit, respectively.
4. A low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device according to claim 1, characterized in that, The low-leakage multiplexing matrix includes multiple low-leakage multiplexed analog switches.
5. A low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device according to claim 1, characterized in that, The analog differential lines, digital control lines, and power lines in the electric field acquisition chamber watertight connector (1) and the multi-channel multiplexing module chamber watertight connector (4) are arranged in groups.
6. A low-disturbance self-calibrating multi-channel multiplexed marine electric field acquisition device according to claim 1, characterized in that, The zero-point calibration channel, reference calibration channel, and external electrode array electrode channels share the same low-leakage multiplexing matrix, the same multiplexing bus discharge unit, and the same ADC.