A Scalable Multi-Physiological Signal Acquisition Interface System

Abstract

This application provides a scalable multi-physiological signal acquisition interface system, comprising: a main control and communication base for providing system control, power management, and external communication functions, and equipped with multiple expansion interface sockets; multiple hot-swappable modular sensor acquisition cards connected to the main control and communication base via the expansion interface sockets, each modular sensor acquisition card for acquiring one or more types of physiological signals; a hardware-level isolation and anti-interference subsystem for providing power isolation and signal isolation; and a hot-swap detection and power management module for real-time monitoring of the insertion and removal status of the expansion interface sockets and controlling the safe power-on and power-off of the acquisition cards. This technical solution achieves plug-and-play and flexible expansion of multiple physiological signal acquisition modules, and ensures the stability and accuracy of signal acquisition in high-interference environments.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a scalable multi-physiological signal acquisition interface system. Background Technology

[0002] With the rapid development of precision medicine and remote health monitoring, multimodal physiological signal fusion analysis has become an important tool for the diagnosis of cardiovascular diseases and the assessment of health status. ECG, SCG, PPG and other signals reflect cardiac function from different dimensions such as electrophysiology, mechanical vibration and hemodynamics, and their simultaneous acquisition and fusion can significantly improve the accuracy and comprehensiveness of diagnosis.

[0003] However, existing physiological signal acquisition systems have many limitations in terms of interface design and anti-interference capabilities: Closed interfaces and poor scalability: Traditional physiological signal acquisition devices (such as multi-lead electrocardiographs and Holter monitors) typically employ a fixed, closed hardware architecture. The types and number of their sensor interfaces are fixed at the factory, making flexible expansion impossible based on actual monitoring needs (such as adding an SCG module to assess cardiac mechanical function or adding multiple PPG channels to monitor blood perfusion in different areas). Users requiring different combinations of signals must purchase different dedicated equipment, resulting in high costs and low equipment utilization.

[0004] Lack of standardization and low compatibility: Different manufacturers and types of physiological signal sensors (such as ECGs with different electrode types, MEMS accelerometers SCGs with different ranges, and PPG sensors with different wavelengths) vary greatly in terms of electrical interfaces, signal levels, and power supply requirements. The lack of a unified interface standard in existing systems leads to poor sensor interchangeability and difficulties in system upgrades and maintenance.

[0005] Insufficient hot-swapping support: During long-term monitoring (such as intensive care or sleep monitoring), it may be necessary to dynamically adjust the monitoring plan according to changes in the patient's condition, such as temporarily adding SCG monitoring or replacing faulty sensors. Most existing systems do not support hot-swapping of sensor modules (i.e., plugging and unplugging while the system is powered on). Forced operation may cause system crashes, data loss, or even hardware damage.

[0006] Severe electromagnetic interference and poor signal quality: Physiological signals are extremely weak (e.g., ECG signal amplitude is approximately 0.5-5mV, SCG signal acceleration amplitude can be as low as 0.1mg), and the acquisition environment is complex (with 50 / 60Hz power frequency interference, radio frequency interference, electromagnetic radiation from other medical equipment, etc.). When multiple sensors are integrated into the same system, their mutual interference (e.g., high-frequency switching noise from PPG-driven LEDs interfering with ECG, and digital circuit noise coupled to the analog front end through the power supply) becomes a key factor affecting signal quality. Existing systems mostly use simple filtering or shielding measures, which cannot completely solve the cross-interference problem between multiple sensors at the hardware level, resulting in a low signal-to-noise ratio and affecting the accuracy of subsequent analysis.

[0007] The contradiction between system integration and portability: In order to collect multiple signals, multiple independent acquisition boxes usually need to be connected to the patient by cables, which leads to cable tangling, limited patient movement, poor comfort, and is not conducive to monitoring in home or mobile scenarios.

[0008] Therefore, there is an urgent need for a new physiological signal acquisition interface system that can solve the above problems, realize the standardization, modularization, and hot-swappable expansion of sensor modules, and provide strong hardware-level anti-interference capabilities to meet the high requirements of modern medical monitoring for flexibility, reliability and signal quality. Summary of the Invention

[0009] This application provides a scalable multi-physiological signal acquisition interface system to enable plug-and-play and flexible expansion of various physiological signal acquisition modules, and to ensure the stability and accuracy of acquired signals in high-interference environments.

[0010] Firstly, a scalable multi-physiological signal acquisition interface system is provided, including: The main control and communication base provides system main control, power management and external communication functions, and is equipped with multiple expansion interface sockets; Multiple hot-swappable modular sensor acquisition cards are connected to the main control and communication base via the expansion interface socket, and each of the modular sensor acquisition cards is used to acquire one or more types of physiological signals; Hardware-level isolation and anti-interference subsystem is used to provide power isolation and signal isolation; The hot-swap detection and power management module is used to monitor the insertion and removal status of the expansion interface socket in real time and control the safe power-on and power-off of the acquisition card.

[0011] In the above technical solution, a main control and communication base is set up to provide system main control, power management and external communication functions, and multiple expansion interface sockets are provided; multiple hot-swappable modular sensor acquisition cards are connected to the main control and communication base through the expansion interface sockets, and each of the modular sensor acquisition cards is used to acquire one or more types of physiological signals; a hardware-level isolation and anti-interference subsystem is used to provide power isolation and signal isolation; a hot-swap detection and power management module is used to monitor the insertion and removal status of the expansion interface sockets in real time and control the safe power-on and power-off of the acquisition cards; thus, the system achieves plug-and-play and flexible expansion of multiple physiological signal acquisition modules, and ensures the stability and accuracy of signal acquisition in high interference environments.

[0012] In one specific implementation scheme, the expansion interface socket adopts a unified mechanical and electrical interface standard to support the plug-and-play and flexible expansion of the modular sensor acquisition card.

[0013] In one specific implementation, the hardware-level isolation and anti-interference subsystem is integrated into the main control and communication base and / or the sensor acquisition card.

[0014] In one specific implementation, the modular sensor acquisition card includes at least two of the following: an electrocardiogram acquisition card, an electrocardiogram acquisition card, and a photoplethysmography (PPG) acquisition card.

[0015] In one specific implementation, the modular sensor acquisition card integrates an identification memory for storing the acquisition card's type, specifications, and calibration information. When the main control and communication base detects the insertion of the acquisition card, it automatically reads the information in the identification memory to complete the configuration.

[0016] In one specific implementation scheme, the hardware-level isolation and anti-interference subsystem includes: Isolated DC-DC converters are used to provide independent isolated power to each expansion interface; A high-speed digital isolator is used to isolate the digital communication signals between the modular sensor acquisition card and the main control and communication base.

[0017] In one possible implementation, the isolated DC-DC converter is located within the main control and communication base, providing an independent isolated power bus for each expansion interface.

[0018] In one specific implementation, each of the modular sensor acquisition cards includes a secondary isolated power conversion circuit for providing secondary isolated power to its analog front-end circuitry.

[0019] In one specific implementation, the digital communication between the main control and communication base and the modular sensor acquisition card adopts the SPI protocol or the I2C protocol.

[0020] Secondly, a multimodal physiological signal acquisition device is provided, including the scalable multimodal physiological signal acquisition interface system described in any one of the claims.

[0021] In the above technical solution, a main control and communication base is set up to provide system main control, power management and external communication functions, and multiple expansion interface sockets are provided; multiple hot-swappable modular sensor acquisition cards are connected to the main control and communication base through the expansion interface sockets, and each of the modular sensor acquisition cards is used to acquire one or more types of physiological signals; a hardware-level isolation and anti-interference subsystem is used to provide power isolation and signal isolation; a hot-swap detection and power management module is used to monitor the insertion and removal status of the expansion interface sockets in real time and control the safe power-on and power-off of the acquisition cards; thus, the system achieves plug-and-play and flexible expansion of multiple physiological signal acquisition modules, and ensures the stability and accuracy of signal acquisition in high interference environments. Attached Figure Description

[0022] Figure 1 This is a structural block diagram of the scalable multi-physiological signal acquisition interface system provided in the embodiments of this application. Detailed Implementation

[0023] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present application will become clearer and more apparent.

[0024] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0025] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0026] To facilitate understanding of the scalable multi-physiological signal acquisition interface system provided in this application embodiment, its application scenario is first explained. The scalable multi-physiological signal acquisition interface system provided in this application embodiment is used to achieve plug-and-play and flexible expansion of various physiological signal acquisition modules, while ensuring the stability and accuracy of acquired signals in high-interference environments. Existing physiological signal acquisition systems have many limitations in interface design and anti-interference capabilities: closed interfaces and poor scalability: Traditional physiological signal acquisition devices (such as multi-lead electrocardiographs and Holter monitors) typically employ a fixed and closed hardware architecture. The types and number of their sensor interfaces are fixed at the factory, making flexible expansion impossible based on actual monitoring needs (such as adding an SCG module to assess cardiac mechanical function, or adding multiple PPG channels to monitor blood perfusion in different areas). If users need to acquire different combinations of signals, they must purchase different dedicated equipment, resulting in high costs and low equipment utilization. Lack of standardization and low compatibility: Different manufacturers and types of physiological signal sensors (such as ECG with different electrode types, MEMS accelerometers SCG with different ranges, and PPG sensors with different wavelengths) vary greatly in terms of electrical interfaces, signal levels, and power supply requirements. The lack of a unified interface standard in existing systems leads to poor sensor interchangeability and difficulties in system upgrades and maintenance. Insufficient hot-swapping support: During long-term monitoring (such as intensive care and sleep monitoring), it may be necessary to dynamically adjust the monitoring plan according to changes in the patient's condition, such as temporarily adding SCG monitoring or replacing faulty sensors. Most existing systems do not support hot-swapping of sensor modules (i.e., plugging and unplugging while the system is powered on), and forced operation may cause system crashes, data loss, or even hardware damage. Severe electromagnetic interference and poor signal quality: Physiological signals are extremely weak (e.g., ECG signal amplitude is approximately 0.5-5mV, and SCG signal acceleration amplitude can be as low as 0.1mg), and the acquisition environment is complex (with 50 / 60Hz power frequency interference, radio frequency interference, and electromagnetic radiation from other medical equipment). When multiple sensors are integrated into the same system, their mutual interference (such as high-frequency switching noise from PPG-driven LEDs interfering with ECG, and digital circuit noise coupled to the analog front end through the power supply) becomes a key factor affecting signal quality. Existing systems often employ simple filtering or shielding measures, which are insufficient to completely resolve cross-interference issues between multiple sensors at the hardware level, resulting in low signal-to-noise ratios and affecting the accuracy of subsequent analysis. There is also a conflict between system integration and portability: to acquire multiple signals, multiple independent acquisition boxes typically need to be connected to the patient via cables, leading to cable tangling, restricted patient movement, poor comfort, and unsuitability for monitoring in home or mobile settings. Therefore, this application provides a scalable multi-physiological signal acquisition interface system to achieve plug-and-play and flexible expansion of multiple physiological signal acquisition modules, while ensuring the stability and accuracy of signal acquisition in high-interference environments. The following detailed description, in conjunction with specific accompanying drawings, illustrates the embodiments.

[0027] refer to Figure 1 , Figure 1 This is a structural block diagram of the scalable multi-physiological signal acquisition interface system provided in the embodiments of this application.

[0028] exist Figure 1 In this application, an embodiment provides a scalable multi-physiological signal acquisition interface system, including: The main control and communication base provides system main control, power management and external communication functions, and is equipped with multiple expansion interface sockets; Multiple hot-swappable modular sensor acquisition cards are connected to the main control and communication base via the expansion interface socket, and each of the modular sensor acquisition cards is used to acquire one or more types of physiological signals; Hardware-level isolation and anti-interference subsystem is used to provide power isolation and signal isolation; The hot-swap detection and power management module is used to monitor the insertion and removal status of the expansion interface socket in real time and control the safe power-on and power-off of the acquisition card.

[0029] In the above technical solution, a main control and communication base is set up to provide system main control, power management and external communication functions, and multiple expansion interface sockets are provided; multiple hot-swappable modular sensor acquisition cards are connected to the main control and communication base through the expansion interface sockets, and each of the modular sensor acquisition cards is used to acquire one or more types of physiological signals; a hardware-level isolation and anti-interference subsystem is used to provide power isolation and signal isolation; a hot-swap detection and power management module is used to monitor the insertion and removal status of the expansion interface sockets in real time and control the safe power-on and power-off of the acquisition cards; thus, the system achieves plug-and-play and flexible expansion of multiple physiological signal acquisition modules, and ensures the stability and accuracy of signal acquisition in high interference environments.

[0030] Specifically, the beneficial effects include: Significantly Enhanced Flexibility and Scalability: The system adopts an innovative architecture combining a main control unit and communication base with multiple hot-swappable modular sensor acquisition cards, granting the system exceptional flexibility. Users can freely select different types or numbers of acquisition cards according to their actual needs, easily connecting them to the main control unit and communication base via expansion interface sockets to achieve rapid integration of various physiological signal acquisition modules. Whether adding new physiological signal acquisition functions or adjusting the combination of acquisition cards according to different experimental or clinical needs, this can be done quickly without affecting the operation of other parts of the system, truly achieving plug-and-play and flexible expansion. This greatly improves the system's adaptability and versatility, meeting diverse usage scenarios.

[0031] Significantly improved ease of operation and maintenance efficiency: Hot-swappable functionality is a major highlight of this system. The hot-swappable detection and power management module can monitor the insertion and removal status of the expansion interface sockets in real time and precisely control the safe power-on and power-off of the data acquisition cards. This means that during system operation, users can directly insert or remove data acquisition cards without shutting down the entire system, without causing any damage to the system, and avoiding the inconvenience and time wastage caused by frequent system starts and stops. At the same time, this design makes equipment maintenance and upgrades extremely simple. When a data acquisition card malfunctions or needs to be updated, staff can quickly replace it without complicated procedures, greatly shortening maintenance time, improving work efficiency, and reducing maintenance costs.

[0032] Signal stability and accuracy are effectively guaranteed: External interference is a significant factor affecting signal quality during physiological signal acquisition. This system's hardware-level isolation and anti-interference subsystem provides reliable protection for signal acquisition. Through power isolation and signal isolation technologies, the influence of external interference sources on the system's internal circuitry is effectively cut off, preventing signal distortion caused by power fluctuations or signal crosstalk, ensuring that the acquired physiological signals are authentic, accurate, and stable. Even in complex, high-interference environments, such as hospital operating rooms and research laboratories, the system can still operate stably, providing high-quality raw data for medical diagnosis and scientific research analysis, improving diagnostic accuracy and the reliability of research results.

[0033] Enhanced System Integration and Reliability: The main control and communication base integrates system control, power management, and external communication functions into one unit. This highly integrated design reduces the number of system components, simplifies the system structure, lowers the risk of failure caused by connecting multiple independent devices, and improves the overall reliability of the system. At the same time, the compact design saves space, facilitating equipment installation and deployment, and is particularly suitable for space-constrained medical environments and research facilities.

[0034] In one specific implementation scheme, the expansion interface socket adopts a unified mechanical and electrical interface standard to support the plug-and-play and flexible expansion of the modular sensor acquisition card.

[0035] In one specific implementation, the hardware-level isolation and anti-interference subsystem is integrated into the main control and communication base and / or the sensor acquisition card.

[0036] In one specific implementation, the modular sensor acquisition card includes at least two of the following: an electrocardiogram acquisition card, an electrocardiogram acquisition card, and a photoplethysmography (PPG) acquisition card.

[0037] In one specific implementation, the modular sensor acquisition card integrates an identification memory for storing the acquisition card's type, specifications, and calibration information. When the main control and communication base detects the insertion of the acquisition card, it automatically reads the information in the identification memory to complete the configuration.

[0038] In one specific implementation scheme, the hardware-level isolation and anti-interference subsystem includes: Isolated DC-DC converters are used to provide independent isolated power to each expansion interface; A high-speed digital isolator is used to isolate the digital communication signals between the modular sensor acquisition card and the main control and communication base.

[0039] In one possible implementation, the isolated DC-DC converter is located within the main control and communication base, providing an independent isolated power bus for each expansion interface.

[0040] In one specific implementation, each of the modular sensor acquisition cards includes a secondary isolated power conversion circuit for providing secondary isolated power to its analog front-end circuitry.

[0041] In one specific implementation, the digital communication between the main control and communication base and the modular sensor acquisition card adopts the SPI protocol or the I2C protocol.

[0042] In one specific implementation scheme, the scalable multi-physiological signal acquisition interface system includes: Main control and communication base: As the core of the system, it provides main control MCU, power management, data storage, and external communication functions (such as Wi-Fi, Bluetooth, and USB). The base is equipped with multiple standardized expansion interface sockets.

[0043] Hot-swappable modular sensor acquisition cards: Each physiological signal (such as ECG, SCG, PPG) corresponds to one or more standardized acquisition cards. The acquisition card connects to the base via a standard interface and includes complete signal conditioning circuitry, an analog-to-digital converter (ADC), and necessary isolation circuitry.

[0044] Standardized mechanical and electrical interfaces: Define unified physical interface standards (including connector type, pin definition, and mechanical dimensions) to ensure physical compatibility between different acquisition cards and bases.

[0045] Hardware-level isolation and anti-interference subsystem: Multi-level isolation measures, including digital isolation, analog isolation and power isolation, are adopted in the base and each acquisition card to cut off the interference propagation path.

[0046] Hot-swap detection and power management module: Real-time monitoring of interface insertion and removal status, enabling safe hot-swap of the data acquisition card, and providing overcurrent and overvoltage protection.

[0047] Furthermore, standardized mechanical and electrical interfaces include: Mechanical interface: Employs high-reliability, multi-pin board-to-board connectors or customized connectors with anti-misfit designs (such as keyways and asymmetrical pin layouts). Connectors must have sufficient mating life (e.g., >10,000 cycles) to meet frequent hot-swapping requirements.

[0048] Electrical interface definition: The interface pins are uniformly defined as the following types of signals: Power supply pins: Provide multiple voltage levels (such as +5V, +3.3V, ±2.5V) to meet the power supply requirements of different sensors and conditioning circuits.

[0049] Digital communication pins: Use standard serial communication protocols (such as SPI, I2C, UART) for communication between the base MCU and the acquisition card ADC or configuration register.

[0050] Control and status pins: including reset signal, interrupt request signal, module detection signal, etc.

[0051] Analog reference pin: Provides a high-precision analog reference voltage to ensure that the reference reference of each acquisition card's ADC is consistent.

[0052] Grounding pin: Strictly distinguish between analog ground and digital ground, and implement a single-point connection at the interface.

[0053] Furthermore, the modular sensor acquisition card includes: Each acquisition card is a fully functional subsystem: ECG acquisition card: Includes an instrumentation amplifier (INA), right leg drive (RLD) circuitry, high-pass / low-pass / notch filters, and a high-resolution ADC (such as a 24-bit Σ-Δ ADC). Supports multi-lead configuration.

[0054] SCG Acquisition Card: Based on MEMS accelerometer, it includes a charge amplifier (if required), a gain programmable amplifier, an anti-aliasing filter, and a high dynamic range ADC.

[0055] PPG acquisition card: includes photodiode, transimpedance amplifier (TIA), LED driver circuit (supports modulation to reduce ambient light interference), and synchronous sampling ADC.

[0056] Local microcontroller: Optionally, each acquisition card can integrate a lightweight MCU to handle local signal preprocessing (such as filtering and feature extraction) and communication protocol conversion, reducing the burden on the base MCU.

[0057] Identification memory: Each acquisition card has a built-in read-only memory (such as EEPROM) that stores the card's unique ID, type (ECG / SCG / PPG), and specifications (such as sampling rate range, gain range, and calibration coefficients). When a new card is inserted, the base MCU can automatically read this information to achieve "plug and play".

[0058] Furthermore, the hardware-level isolation and anti-interference subsystem adopts a layered isolation strategy, including: Power isolation: Base side: An isolated DC-DC converter is used to provide an independent, isolated power output for each expansion interface. This prevents noise coupling between different acquisition cards through the power path.

[0059] On the acquisition card side: A low-power isolated DC-DC converter or charge pump is used between the analog and digital sections of the acquisition card to provide clean, isolated power to analog circuits (such as amplifiers and ADCs).

[0060] Signal isolation: Digital isolation: A high-speed digital isolator (such as a capacitively or magnetically coupled isolation chip with a rate >10Mbps) is used between the digital communication interface (SPI / I2C) of the acquisition card and the base. This blocks digital noise (such as clock jitter and switching noise) from propagating to the sensitive analog front end.

[0061] Analog isolation: For extremely high-precision applications, analog isolation can be achieved using linear optocouplers or isolation amplifiers before the analog signal enters the ADC, but this is costly. Typically, digital isolation can meet most needs through careful PCB layout and power isolation design.

[0062] PCB layout and shielding: The PCBs of the base and the acquisition card are strictly divided into analog and digital areas.

[0063] Grounding is applied to the analog signal traces, and shielded cables are used to connect the sensor probes.

[0064] Local shielding is applied to high-frequency noise sources (such as LED driver circuits and switching power supplies).

[0065] Furthermore, the hot-swap detection and power management module includes: Insertion / removal detection circuit: Utilizes a dedicated detection pin in the interface. When the data acquisition card is inserted, this pin is pulled low (or high), and the base MCU triggers an interrupt by detecting the level change of this pin, initiating the hot-plugging process.

[0066] Hot-swap processing procedure: Insertion detected: The MCU pauses the data acquisition task associated with this interface.

[0067] Identity verification: The identity information in the EEPROM of the acquisition card is read through the I2C bus to confirm the card type and parameters.

[0068] Power-on sequence: Power on each power supply required by the acquisition card in a predefined order and with a delay, avoiding surge current.

[0069] Initialization configuration: Based on the identity information, configure the communication protocol (such as SPI clock rate), ADC sampling rate, gain and other parameters between the base and the acquisition card.

[0070] Start data acquisition: After initialization, resume the data acquisition task and add the new acquisition card to the data stream.

[0071] Unplugging process: Upon detecting that the card has been unplugged, the MCU immediately stops reading data from the card, releases the relevant resources, and records the unplugging event.

[0072] Protection circuit: Overcurrent protection (such as a resettable fuse or electronic fuse) and overvoltage protection devices are set on the power path of each interface to prevent damage to the equipment caused by power surges due to hot plugging.

[0073] In this embodiment, the beneficial effects include: High scalability and flexibility: Through standardized interfaces, users can flexibly combine and expand sensor modules according to specific monitoring needs (such as ECG+PPG for resting monitoring and ECG+SCG+PPG for cardiac function assessment), achieving "one machine for multiple uses" and significantly reducing equipment cost and complexity.

[0074] Plug and play with high compatibility: The data acquisition card has built-in identification information, and the system can automatically identify the card type and load the corresponding driver and configuration without manual settings, which greatly simplifies the operation process and improves the interchangeability of sensor modules from different manufacturers.

[0075] Supports hot-swapping for improved availability: Allows for the safe addition, removal, or replacement of sensor modules during system operation without restarting the system, greatly facilitating scheme adjustments and equipment maintenance during long-term monitoring.

[0076] Exceptional anti-interference capability: Through hardware-level power isolation, digital isolation, and optimized PCB design, electromagnetic interference paths between multiple sensors and inside and outside the system are fundamentally cut off, ensuring the acquisition quality of weak physiological signals (especially SCG and ECG) and providing a reliable data foundation for subsequent high-precision analysis.

[0077] High integration and portability: All acquisition modules are integrated on a compact base, avoiding the hassle of multiple devices and cables, improving patient comfort and freedom of movement, and making it particularly suitable for home monitoring, out-of-hospital emergency care and wearable device applications.

[0078] Easy maintenance and upgrades: A single faulty data acquisition card only requires replacement of that card; the entire system does not need repair. New sensor technologies (such as the new PPG sensor) can be quickly integrated into existing systems through the development of new data acquisition cards, protecting user investment.

[0079] In one specific feasible implementation, the system of this application is centered on a main control and communication base, surrounded by multiple modular sensor acquisition cards. Specifically, it includes: Main control and communication base: Core MCU: A high-performance ARM Cortex-M4 core microcontroller (such as STMicroelectronics' STM32F407) is selected to be responsible for system control, data processing and communication scheduling.

[0080] Power Management Unit (PMU): Converts external input power (such as lithium battery, USB 5V) into various voltages required by the system. Crucially, it contains multiple isolated DC-DC converters, each providing independent isolated power to an expansion interface.

[0081] Expansion interface socket: The base plate is equipped with four identical 60-pin high-speed board-to-board connectors (such as the Hirose DF60 series) as a standardized expansion interface.

[0082] Communication module: integrates Wi-Fi (802.11n) and Bluetooth 5.0 modules for wirelessly transmitting collected physiological data to cloud servers or mobile terminals.

[0083] Storage unit: Built-in 4GB eMMC memory for temporary storage of acquired data.

[0084] Modular sensor acquisition card: Users can insert ECG, SCG, and PPG cards into any available interface on the base as needed. The system can support up to four different physiological signal acquisition cards simultaneously.

[0085] Its data stream includes: Physiological signals are collected by sensor probes (such as ECG electrodes, SCG accelerometers, and PPG photosensitive probes) and transmitted to the corresponding acquisition card via flexible cables.

[0086] The analog front-end inside the acquisition card amplifies, filters, and conditions the signal.

[0087] The conditioned signal is converted into a digital quantity by the ADC.

[0088] The data acquisition card transmits digital data to the base MCU via the SPI interface.

[0089] The base MCU packages and timestamps data from different cards (which can be combined with the aforementioned clock synchronization patent technology), and then sends it out via Wi-Fi or Bluetooth, or stores it in the local eMMC.

[0090] In one feasible implementation, the standardized expansion interface, taking a 60-pin connector as an example, includes the following pin definitions: Power supply (12 pins): VCC_ISO_5V (4 pins): Isolated +5V power supply, providing a maximum current of 500mA.

[0091] VCC_ISO_3V3 (4 pins): Isolated +3.3V power supply, providing a maximum current of 300mA.

[0092] VCC_ANA_2V5 (2 pins): Precision +2.5V analog reference voltage.

[0093] GND_ISO (2 pins): Isolation power ground.

[0094] Digital communication group (16 pins): SPI_CLK, SPI_MOSI, SPI_MISO (2 pins each): SPI bus, supporting high-speed data transmission (up to 50MHz).

[0095] I2C_SCL, I2C_SDA (2 pins each): I2C bus, used to read the EEPROM of the acquisition card and configure low-speed devices.

[0096] UART_TX, UART_RX (2 pins each): Spare asynchronous serial ports.

[0097] GPIO1-GPIO4 (4 pins): General purpose input / output, used for control signals such as interrupts and resets.

[0098] Simulation and State Group (8 pins): AGND (4 pins): Analog ground.

[0099] DETECT (1 pin): Hot-swap detection pin, pulled low by a resistor when the data acquisition card is inserted.

[0100] PRESENT (1 pin): Acquisition card presence indication signal.

[0101] ALERT (1 pin): Data acquisition card fault alarm signal.

[0102] CAL_SIG (1 pin): Calibration signal input.

[0103] Mechanical and Reserved (24 pins): Used for connector fixing, anti-misfit keyway, and future function expansion.

[0104] In one feasible implementation, the core components of the ECG acquisition card include: 1. Analog Front End (AFE): An integrated ECG AFE chip is selected, such as TI's ADS129x series (e.g., ADS1292R). This chip integrates: Multi-channel low-noise programmable gain amplifier (PGA).

[0105] High-resolution 24-bit ADC.

[0106] Built-in right leg drive amplifier.

[0107] Wilson Central Terminal (WCT) and Goldberg Terminal (GCT) generation circuits.

[0108] Lead detachment detection circuit.

[0109] This chip greatly simplifies the design and provides excellent common-mode rejection ratio (CMRR > 110dB).

[0110] 2. Signal conditioning: A simple RC filter can be added before the AFE to filter out some high-frequency noise.

[0111] 3. Isolation circuit: Power isolation: Use a small, isolated DC-DC converter (such as TI's ISO7220) to convert the VCC_ISO_5V supplied by the base to the isolated power required by the AFE chip.

[0112] Digital isolation: A high-speed digital isolator (such as ADI's ADuM3151) is used between the AFE's SPI interface and the base station, with an isolation rate of up to 150Mbps.

[0113] 4. Identification EEPROM: A small AT24C02 chip containing the memory card model ("ECG-8L"), serial number, default sampling rate (500 SPS), calibration data, etc.

[0114] 5. Interface: Connects to the base via a 60-pin connector.

[0115] In one specific feasible implementation, the SCG acquisition card addresses the characteristics of MEMS accelerometer signals, including: 1. Sensor: Select a low-noise, high-bandwidth triaxial MEMS accelerometer, such as ST's LIS3DHH or Analog Devices' ADXL355. Its range is set to ±2g or ±4g to capture weak SCG signals (typically <0.1g).

[0116] 2. Signal Conditioning: Since accelerometer outputs are typically analog voltages or digital SPI interfaces, if it's an analog output, a low-noise operational amplifier is needed for buffering and level shifting. If it's a digital output, it can communicate directly with the base station via an isolator.

[0117] 3. Anti-aliasing filter: Design a low-pass filter with a cutoff frequency of 100Hz (the main energy of the SCG signal is concentrated in 1-50Hz) to prevent high-frequency noise aliasing.

[0118] 4. ADC: If the sensor has an analog output, an external 16-bit or 24-bit high-precision ADC (such as AD7685) is required. If the sensor has a digital output, its built-in ADC can be used directly.

[0119] 5. Isolation and Identification: Similar to the ECG card, it employs power and digital isolation and is equipped with EEPROM.

[0120] In a specific feasible implementation, the key aspects of the PPG acquisition card lie in optical measurement and noise suppression, including: 1. Optical components: including a green LED (for detecting heart rate variability) and an infrared LED (for estimating blood oxygen saturation), as well as a photodiode (PD).

[0121] 2. Transimpedance Amplifier (TIA): Converts the weak current signal generated by the photodiode into a voltage signal. The TIA must have low bias current and low noise characteristics.

[0122] 3. LED Driver Circuit: A constant current source is used to drive the LED, and pulse modulation is supported. By modulating the LED's on / off frequency and using synchronous detection technology, interference from ambient light can be greatly suppressed.

[0123] 4. Signal Conditioning and ADC: The signal output from the TIA passes through a programmable gain amplifier (PGA) and a low-pass filter before being sampled by the ADC. The ADC sampling must be synchronized with the LED drive pulses.

[0124] 5. Isolation and Identification: Same as above.

[0125] In a specific feasible implementation, hardware-level isolation and interference immunity isolation strategies include: Base side: The main power supply (e.g., +12V) is input to an isolated DC-DC converter (e.g., Murata NXE2 series).

[0126] The converter generates a set of independent, isolated VCC_ISO_5V and VCC_ISO_3V3 for each expansion interface.

[0127] The isolation power ground GND_ISO for each interface is independent on the base side.

[0128] On the acquisition card side: The isolated DC-DC converter on the acquisition card (such as the transformer driven by TI's SN6501) converts VCC_ISO_5V to the isolated power supply VCC_AFE required by AFE.

[0129] The analog ground AGND_AFE of AFE and the digital ground DGND are connected at a single point on the card.

[0130] High-speed digital isolators (such as ADI's ADuM1402) are located between the digital interface of the AFE and the base connector. Different power supplies (VCC_AFE and VCC_ISO_3V3) and grounds (AGND_AFE and GND_ISO) are used on both sides of the isolator, completely eliminating ground loops.

[0131] PCB layout: On the PCB of the base and the acquisition card, a clear isolation band (MOAT) is used to separate the analog and digital areas.

[0132] All signals crossing the isolation zone must pass through the isolation device.

[0133] Analog signal traces should be kept as short as possible, and differential routing should be used (such as for ECG signals).

[0134] In a specific feasible implementation, the hot-plug detection and power management process is as follows: Initial state: The base MCU periodically scans the DETECT pin level of each interface.

[0135] Insertion detected: When the DETECT pin of a certain interface changes from high level to low level, the MCU triggers an interrupt and records the interface number.

[0136] Power-on: The MCU controls the PMU to turn on the VCC_ISO_5V and VCC_ISO_3V3 power supplies of this interface in sequence according to the predefined timing, with a 10ms delay in between to stabilize the power supply.

[0137] Identification: After the power supply stabilizes, the MCU attempts to read the EEPROM of the acquisition card on this interface via the I2C bus. If the read is successful and the data verification is correct, the card type and parameters are obtained; otherwise, it is marked as an unknown card or a faulty card.

[0138] Initial configuration: MCU, depending on the card type: Configure the SPI interface parameters (clock polarity, phase, rate) for communication with this card.

[0139] The configuration register of the AFE of the acquisition card is written via SPI to set the sampling rate, gain, lead configuration, etc.

[0140] Send a calibration command to enable the AFE to perform internal self-calibration.

[0141] Start Acquisition: After initialization, the MCU adds the acquisition card to the data acquisition loop and begins reading its ADC data.

[0142] Disconnection detected: When the DETECT pin changes from low to high, the MCU immediately stops reading data from the card, shuts down its power, and releases related resources.

[0143] In a specific feasible implementation, the physical layout of a specific interface system includes: The base is a PCB board of about 10cm x 6cm, with the main control MCU and PMU in the center and four 60-pin connectors evenly distributed around it.

[0144] The ECG, SCG, and PPG acquisition cards are all small PCBs of approximately 3cm x 4cm, which are vertically inserted into the base via board-to-board connectors to form a compact stacked structure.

[0145] The sensor probe is connected to a connector on the edge of the data acquisition card via a thin, flexible ribbon cable.

[0146] Performance testing includes: Hot-swap test: During continuous data acquisition, different acquisition cards were repeatedly plugged in and out. The results showed that the system could correctly detect the plugging and unplugging events, automatically complete initialization and resource reclamation, and no crashes or data corruption occurred.

[0147] Interference immunity test: The system was placed in an environment with strong 50Hz power frequency interference and mobile phone radio frequency interference. Compared with traditional non-isolated systems, the ECG and SCG signals acquired by the system of this invention have stable baselines, the 50Hz noise amplitude is reduced by more than 90%, and the signal-to-noise ratio of the PPG signal is significantly improved.

[0148] Multimodal synchronous acquisition: Simultaneously connect ECG, SCG, and PPG cards to collect volunteer data. By analyzing the time difference (PEP) between the ECG R wave and the SCG AO point, and the time difference (PWTT) between the ECG R wave and the PPG peak value, it is demonstrated that the multi-channel signals have good synchronization (thanks to the aforementioned patented clock synchronization technology combined with this interface system), which can be used for accurate physiological parameter calculation.

[0149] This application also provides a multimodal physiological signal acquisition device, including any of the scalable multimodal physiological signal acquisition interface systems described in any one of the claims.

[0150] In the above technical solution, a main control and communication base is set up to provide system main control, power management and external communication functions, and multiple expansion interface sockets are provided; multiple hot-swappable modular sensor acquisition cards are connected to the main control and communication base through the expansion interface sockets, and each of the modular sensor acquisition cards is used to acquire one or more types of physiological signals; a hardware-level isolation and anti-interference subsystem is used to provide power isolation and signal isolation; a hot-swap detection and power management module is used to monitor the insertion and removal status of the expansion interface sockets in real time and control the safe power-on and power-off of the acquisition cards; thus, the system achieves plug-and-play and flexible expansion of multiple physiological signal acquisition modules, and ensures the stability and accuracy of signal acquisition in high interference environments.

[0151] Those skilled in the art will know that this application can be implemented as a system, method, or computer program product.

[0152] Therefore, this disclosure can be implemented in the following forms: it can be entirely hardware, entirely software (including firmware, resident software, microcode, etc.), or a combination of hardware and software, generally referred to herein as a "circuit," "module," or "system." Furthermore, in some embodiments, this application can also be implemented as a computer program product in one or more computer-readable media, the computer-readable media containing computer-readable program code.

[0153] Any combination of one or more computer-readable media may be used. A computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus, or device.

[0154] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application. Based on this, various substitutions and improvements can be made to this application, all of which fall within the protection scope of this application.

Claims

1. A scalable multi-physiological signal acquisition interface system, characterized in that, include: The main control and communication base provides system main control, power management and external communication functions, and is equipped with multiple expansion interface sockets; Multiple hot-swappable modular sensor acquisition cards are connected to the main control and communication base via the expansion interface socket, and each of the modular sensor acquisition cards is used to acquire one or more types of physiological signals; Hardware-level isolation and anti-interference subsystem is used to provide power isolation and signal isolation; The hot-swap detection and power management module is used to monitor the insertion and removal status of the expansion interface socket in real time and control the safe power-on and power-off of the acquisition card.

2. The scalable multi-physiological signal acquisition interface system according to claim 1, characterized in that, The expansion interface socket adopts a unified mechanical and electrical interface standard to support the plug-and-play and flexible expansion of the modular sensor acquisition card.

3. The scalable multi-physiological signal acquisition interface system according to claim 2, characterized in that, The hardware-level isolation and anti-interference subsystem is integrated into the main control and communication base and / or the sensor acquisition card.

4. The scalable multi-physiological signal acquisition interface system according to claim 3, characterized in that, The modular sensor acquisition card includes at least two of the following: electrocardiogram acquisition card, seismogram acquisition card, and photoplethysmography (PPG) acquisition card.

5. The scalable multi-physiological signal acquisition interface system according to claim 4, characterized in that, The modular sensor acquisition card integrates an identification memory to store the card's type, specifications, and calibration information. When the main control and communication base detects the insertion of the acquisition card, it automatically reads the information from the identification memory to complete the configuration.

6. The scalable multi-physiological signal acquisition interface system according to claim 5, characterized in that, The hardware-level isolation and anti-interference subsystem includes: Isolated DC-DC converters are used to provide independent isolated power to each expansion interface; A high-speed digital isolator is used to isolate the digital communication signals between the modular sensor acquisition card and the main control and communication base.

7. The scalable multi-physiological signal acquisition interface system according to claim 6, characterized in that, The isolated DC-DC converter is located within the main control and communication base, providing an independent isolated power bus for each expansion interface.

8. The scalable multi-physiological signal acquisition interface system according to claim 7, characterized in that, Each of the modular sensor acquisition cards contains a secondary isolated power conversion circuit to provide secondary isolated power to its analog front-end circuit.

9. The scalable multi-physiological signal acquisition interface system according to claim 8, characterized in that, The digital communication between the main control and communication base and the modular sensor acquisition card adopts the SPI protocol or the I2C protocol.

10. A multimodal physiological signal acquisition device, characterized in that, Includes the scalable multi-physiological signal acquisition interface system as described in any one of claims 1-9.

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