A diver physiological information monitoring and positioning system

Abstract

The present application relates to diver physiological information monitoring and positioning system, including: shore-based display control system for displaying monitoring diver's physiological information and positioning information; deck unit, including first and second water acoustic reference marks, which are both in communication connection with the shore-based display control system; physiological information acquisition module, for real-time acquisition of diver's physiological information; through-conduction integrated buoy, including underwater processing unit, underwater transceiver circuit in communication connection with the underwater processing unit, third water acoustic transducer connected with the underwater transceiver circuit and depth information detection unit connected with the underwater processing unit, the physiological information acquisition module is in communication connection with the underwater processing unit. The present application can realize diver's physiological information monitoring and positioning.

Description

Technical Field

[0001] This invention relates to the field of underwater rescue technology, and in particular to a system for monitoring and locating the physiological information of divers. Background Technology

[0002] Diving training is essential for both diving enthusiasts and professionals. It primarily develops divers' diving skills while also enhancing their safety awareness and ability to respond to emergencies. Given the complex and ever-changing marine environment, ensuring the safety of divers during training is paramount.

[0003] Traditional diving suits primarily protect divers from water pressure and low temperatures, playing a vital role in routine diving activities. These suits are typically made of waterproof materials and equipped with basic breathing apparatus and pressure regulation systems, providing essential life support within a certain depth range. However, with the expansion and increasing complexity of underwater activities, the limitations of traditional diving suits are becoming increasingly apparent.

[0004] Currently, to monitor divers' physiological condition, most divers wear physiological monitoring watches, and each is accompanied by an underwater safety officer. This system heavily relies on the safety officer's experience and ability; failure to detect physiological abnormalities in a timely manner can threaten lives. Furthermore, a shortage of safety officers can lead to low training efficiency. Some methods of monitoring divers' physiological condition also rely on diving bells, which are inflexible. Summary of the Invention

[0005] The purpose of this invention is to provide a diver physiological information monitoring and positioning system. By deploying a shore-based display and control system and a deck unit at the shore-based end, and deploying a physiological information acquisition module and a communication and navigation integrated underwater buoy at the underwater end, the system utilizes communication between the shore-based end and the underwater end to achieve accurate monitoring of the diver's physiological information and positioning.

[0006] Therefore, the present invention is implemented using the following technical solution: This application relates to a diver's physiological information monitoring and positioning system, including: Shore-based display and control system, which is used to display and monitor the physiological and positioning information of divers; The deck unit includes a first underwater acoustic reference beacon and a second underwater acoustic reference beacon, both of which are communicatively connected to the shore-based display and control system. The first underwater acoustic reference beacon includes a first processing unit, a first transceiver circuit communicatively connected to the first processing unit, and a first underwater acoustic transducer connected to the first transceiver circuit. The second underwater acoustic reference beacon includes a second processing unit, a second underwater acoustic transducer, and a second receiving circuit. The electrical signal output by the second underwater acoustic transducer is transmitted to the second processing unit through the second receiving circuit. Underwater systems, including: The physiological information acquisition module, which is installed on the diving suit itself, is used to acquire the diver's physiological information in real time. The underwater buoy, which integrates communication and navigation, includes an underwater processing unit, an underwater transceiver circuit connected to the underwater processing unit, a third underwater acoustic transceiver connected to the underwater transceiver circuit, and a depth information detection unit connected to the underwater processing unit. The physiological information acquisition module is connected to the underwater processing unit. A power module, which provides electrical energy to the electrical components in the underwater system; In use, the first and second underwater acoustic reference beacons are spaced at a preset distance to place the corresponding underwater acoustic transducers in the water. The diver's physiological information signals are received by the deck unit through the underwater system and sent to the shore-based display and control system for display. The process of locating the diver is as follows: Positioning query signals issued by the shore-based display and control system; After both the first and second underwater acoustic reference beacons receive the positioning query signal, the first underwater acoustic reference beacon sends a positioning query signal, and at the same time, both the first and second underwater acoustic reference beacons start timing. After receiving the positioning question and answer signal, the integrated communication and navigation underwater buoy transmits back the positioning response signal and the depth information detected by the depth information detection unit; The first and second underwater acoustic reference markers respectively analyze the location question and answer signals and stop timing; Based on the first time delay obtained from the first underwater acoustic reference beacon, the second time delay obtained from the second underwater acoustic reference beacon, the depth information, and the preset positions of the first and second underwater acoustic reference beacons, the first processing unit calculates the diver's location. The diver's location is displayed in real time on the shore-based display and control system.

[0007] In some embodiments of this application, the power module includes a first power unit and a second power unit, and the physiological information acquisition module is disposed on the diving suit and in contact with the diver's chest, and includes: Main control unit; A photoplethysmography (PPG) sensor, connected to the main control unit, is used to measure the diver's heart rate and blood oxygen saturation. A breathing rate sensor, which is connected to the main control unit, is used to measure the diver's breathing rate; The first power supply unit provides electrical energy to the electrical components in the physiological information acquisition module; The second power supply unit provides power to the electrical components in the integrated communication and navigation underwater buoy, which is also mounted on the diving suit and is positioned differently from the physiological information acquisition module.

[0008] In some embodiments of this application, the depth information detection unit is a pressure sensor, and the underwater processing unit receives the pressure information fed back by the pressure sensor and converts it into depth information.

[0009] In some embodiments of this application, the first processing unit employs FPGA multi-channel parallel computing to differentiate and demodulate the positioning response signal and the physiological information signal.

[0010] In some embodiments of this application, the first processing unit further includes: The signal sampling module is used to receive the signal output from the first underwater acoustic transducer through the first receiving circuit, perform AD sampling, and output the sampled data. The preprocessing module uses a first-level FFIO buffer to cache the sampled data and then performs data filtering. Finally, it outputs the preprocessed signal through a second-level FFIO buffer. The signal detection module is configured to perform the following: The preprocessed signal is subjected to a Fourier transform for time-domain to frequency-domain mapping. When performing time-domain to frequency-domain mapping using the Fourier transform, the length of the selected discrete time-domain sampling point is greater than the length of the preprocessed signal. When performing FIFO buffering in the preprocessing module, the signal in-and-out sliding length is the difference between the length of the discrete time-domain sampling point and the length of the preprocessed signal. The frequency domain data obtained by the transformation is then subjected to inverse Fourier transform for frequency-time domain mapping. If the transformed time-domain data meets the threshold determination condition, the data signal is output.

[0011] In some embodiments of this application, the signal sampling module includes a first amplification module, a filtering module, a second amplification module, and an ADC sampling module connected in sequence, wherein the first amplification module receives a signal output from a first underwater acoustic transducer.

[0012] In some embodiments of this application, the filtering module is a bandpass filter.

[0013] In some embodiments of this application, when the signal output by the first underwater acoustic transducer through the first receiving circuit is a positioning question-and-answer signal, the first time delay obtained from the first underwater acoustic reference and the second time delay obtained from the second underwater acoustic reference are compensated respectively, specifically as follows: Under time-frequency mapping, the time delay deviation Δτ is obtained based on the starting position of the preprocessed signal, the length L1 of the discrete time-domain sampling point, the length L1 of the preprocessed signal, and the sampling frequency fs. Based on the time delay deviation Δτ, the first time delay τ1 and the second time delay τ2 are compensated respectively; Using the compensated first time delay τ1', the compensated second time delay τ2', depth information, and the preset positions of the first and second underwater acoustic reference points, the first processing unit calculates the diver's location.

[0014] In some embodiments of this application, obtaining the time delay deviation Δτ, the compensated first time delay, and the compensated second time delay specifically involves: Obtain the starting position of the preprocessed signal corresponding to the sampling point position x under the length of the discrete time domain sampling points; Calculate the time delay deviation Δτ = (L1 - L2 - x) * fs; Calculate the first time delay after compensation τ1'=τ1-△τ and the second time delay after compensation τ1'=τ1-△τ.

[0015] Compared with existing technologies, the diver physiological information monitoring and positioning system provided in this application has the following advantages and beneficial effects: The physiological information monitoring and positioning system involved in this application does not require a diving bell. It only requires a shore-based display and control system and a deck unit at the shore-based end, and an underwater system at the underwater end. By utilizing the communication between the two, the physiological and positioning information of the diver can be displayed on the shore-based display and control system. The system has a simple structure and low cost. Moreover, the shore-based display and control system can actively obtain the diver's positioning information at any time to ensure the diver's life safety.

[0016] Other features and advantages of the present invention will become clearer after reading the detailed embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of an embodiment of the diver physiological information monitoring and positioning system proposed in this invention; Figure 2 This is a schematic diagram of the shore-based system in one embodiment of the diver physiological information monitoring and positioning system proposed in this invention; Figure 3 This is a block diagram illustrating the principle of the physiological information acquisition module in one embodiment of the diver physiological information monitoring and positioning system proposed in this invention. Figure 4 This is a schematic diagram of the principle of an integrated communication and navigation buoy in one embodiment of the diver physiological information monitoring and positioning system proposed in this invention; Figure 5 This is a flowchart illustrating the acquisition of positioning information in an embodiment of the diver physiological information monitoring and positioning system proposed in this invention; Figure 6 This is a schematic diagram illustrating the location calculation of positioning information in an embodiment of the diver physiological information monitoring and positioning system proposed in this invention; Figure 7 This is a schematic diagram illustrating the acquisition of time delay deviation Δτ in one embodiment of the diver physiological information monitoring and positioning system proposed in this invention; Figure label: 100. Shore-based display and control system; 200. Deck unit; 210. First underwater acoustic reference beacon; 211. First processing unit; 212. First transmitting circuit; 213. First receiving circuit; 214. First underwater acoustic transducer; 220. Second underwater acoustic reference beacon; 221. Second processing unit; 222. Second receiving circuit; 223. Second underwater acoustic transducer; 300. Physiological information acquisition module; 310. Main control unit; 320. Photoplethysmography pulse wave sensor; 330. Respiratory rate sensor; 400. Integrated communication and navigation buoy; 410. Underwater processing unit; 420. Underwater transmitting circuit; 430. Underwater receiving circuit; 440. Third underwater acoustic transducer; 450. Depth information detection unit; 510. First power supply unit; 520. Second power supply unit. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. In the description of this invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0022] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0023] To achieve the monitoring of divers' physiological and location information, this application relates to a divers' physiological information monitoring and location system, see [link to relevant documentation]. Figure 1 It includes a shore-based system and an underwater system. The shore-based system is located on the shore, while the underwater system is mounted on the diving suit.

[0024] See Figure 2 The shore-based system includes a shore-based display and control system 100 and a deck unit 200 connected to the shore-based display and control system 100; see also Figure 3 and Figure 4 The underwater system includes a physiological information acquisition module 300, a communication and navigation integrated underwater buoy 400 connected to the physiological information acquisition module 300, and a power module (not shown). The power module provides electrical energy to the electrical components in the underwater system.

[0025] In some embodiments of this application, the shore-based display and control system 100 is mainly used to send positioning query signals, display physiological information, and display positioning information when actively querying the diver's positioning information.

[0026] See back Figure 2 The deck unit 200 includes a first underwater acoustic reference beacon 210 and a second underwater acoustic reference beacon 220.

[0027] The first underwater acoustic reference 210 includes a first processing unit 211, a first transceiver circuit, and a first underwater acoustic transducer 214.

[0028] The first transceiver circuit includes a first transmitting circuit 212 and a first receiving circuit 213, both of which are connected to the first processing unit 211. A first underwater acoustic transducer 214 is connected to both the first transmitting circuit 212 and the first receiving circuit 213.

[0029] The first underwater acoustic transducer 214 is used for the conversion of underwater acoustic signals to electrical signals. The first transmitting circuit 212 sends the positioning query signal to the first underwater acoustic transducer 214, causing the first underwater acoustic transducer 214 to output underwater acoustic signals. The physiological information underwater acoustic signal and the positioning response signal are received by the first underwater acoustic transducer 214 and converted into electrical signals, which are then received by the first receiving circuit 213.

[0030] The second underwater acoustic reference beacon 220 includes a second processing unit 221, a second receiving circuit 222, and a second underwater acoustic transducer 223. The second underwater acoustic reference beacon 220 does not have a signal transmission function; it is only used to receive signals from the second underwater acoustic transducer 223.

[0031] In some embodiments of this application, see Figure 3 and Figure 4 The physiological information acquisition module 300 is used to acquire the diver's physiological information in real time (e.g., heart rate, blood oxygen saturation, respiratory rate, etc.).

[0032] The underwater buoy 400, which integrates communication and navigation, includes an underwater processing unit 410, an underwater transceiver circuit (not shown), a third underwater acoustic transducer 440, and a depth information detection unit 450. The underwater processing unit 410 is the data processing core of the underwater system. The underwater transceiver circuit includes an underwater transmitting circuit 420 and an underwater receiving circuit 430, both of which are connected to the underwater processing unit 410. The third underwater acoustic transducer 440 is connected to both the underwater transmitting circuit 420 and the underwater receiving circuit 430.

[0033] The physiological information acquisition module 300 is connected to the underwater processing unit 410 and is used to acquire physiological information signals.

[0034] In some embodiments of this application, the depth information detection unit 450 may be selected, for example, a pressure sensor, which can be used to convert underwater pressure into depth information to achieve depth information detection.

[0035] The underwater processing unit 410 sends the physiological information signal from the physiological information acquisition module 300 to the underwater transmitting circuit 420. The underwater transmitting circuit 420 then sends the physiological information signal to the third underwater acoustic transducer 440. The third underwater acoustic transducer 440 is used for underwater acoustic signal / electrical signal conversion, so that the physiological information underwater acoustic signal can be sent to the first underwater acoustic transducer 214 and the second underwater acoustic transducer 223.

[0036] When the first underwater acoustic transducer 214 outputs the positioning query signal issued by the shore-based display and control system 100, it is received by the third underwater acoustic transducer 440 and then sent to the underwater processing unit 410 through the underwater receiving circuit 430. After being processed by the underwater processing unit 410, the underwater processing unit 410 issues a positioning response signal and depth information.

[0037] The positioning response signal and depth information are transmitted to the third underwater acoustic transducer 440 through the underwater transmitting circuit 420. The third underwater acoustic transducer 440 is used for underwater acoustic signal / electrical signal conversion, so that the positioning response signal and depth information can be transmitted to the first underwater acoustic transducer 214 and the second underwater acoustic transducer 223.

[0038] In some embodiments of this application, for ease of arrangement, the physiological information acquisition module 300 and the integrated communication and navigation buoy 400 are arranged in different positions on the diving suit. Therefore, the power module can be divided into a first power unit 510 and a second power unit 520, see [link to relevant documentation]. Figure 3 The first power supply unit 510 is used to provide power to the electrical components in the physiological information acquisition module 300, and the second power supply unit 520 is used to provide power to the electrical components in the communication and navigation integrated underwater buoy 400.

[0039] When in use, the physiological information acquisition module 300 needs to be in contact with the diver's chest. The integrated communication and navigation buoy 400 can be designed according to the size of the spare helium cylinder, and the spare helium cylinder can be placed in a different position without changing the structure of the diving suit.

[0040] In some embodiments of this application, see reference 1. Figure 3 The physiological information acquisition module 300 includes a main control unit 310, a photoplethysmography pulse wave sensor 320, a respiratory rate sensor 330, and a first power supply unit 510.

[0041] The main control unit 310 is responsible for controlling the photoplethysmography sensor 320 to collect the diver's heart rate and blood oxygen saturation, controlling the respiratory rate sensor 330 to collect the diver's respiratory rate, and running an algorithm to process the collected raw signals to obtain specific values.

[0042] The first power supply unit 510 may include a power management chip and a lithium polymer battery.

[0043] In some embodiments of this application, since both the physiological information acquisition module 300 and the integrated communication and navigation buoy 400 are located underwater, the interfaces used for electrical signal transmission are all watertight interfaces.

[0044] As described above, the upload path for physiological information signals is: physiological information acquisition module 300 → underwater processing unit 410 → underwater transmitting circuit 420 → third underwater acoustic transducer 440 → first underwater acoustic transducer 214 (second underwater acoustic transducer 223) → first receiving circuit 213 (second receiving circuit 222) → first processing unit 211 (second processing unit 221) → shore-based display and control system 100.

[0045] The path for sending the location query signal is as follows: shore-based display and control system 100 → first processing unit 211 (second processing unit 221) → first transmitting circuit 212 → first underwater acoustic transducer 214 → third underwater acoustic transducer 440 → underwater receiving circuit 430 → underwater processing unit 410.

[0046] The upload path for the positioning response signal and depth information is as follows: underwater processing unit 410 → underwater transmitting circuit 420 → third underwater acoustic transducer 440 → first underwater acoustic transducer 214 (second underwater acoustic transducer 223) → first receiving circuit 213 (second receiving circuit 222) → first processing unit 211 (second processing unit 221) → shore-based display and control system 100.

[0047] In some embodiments of this application, see Figure 5 and Figure 6 This describes the specific implementation of obtaining location information.

[0048] When using this diver physiological information monitoring and positioning system, after the diver enters the water, the first underwater acoustic reference beacon 210 and the second underwater acoustic reference beacon 220 need to be separated by a preset distance, and then the corresponding first underwater acoustic transducer 214 and second underwater acoustic transducer 223 should be placed in the water.

[0049] To facilitate the description of the diver's position, the position A (x1, y1, z1) of the first underwater acoustic reference 210 and the position B (x2, y2, z2) of the second underwater acoustic reference 220 will be known in advance. The water surface is taken as the xoy plane, and the straight line AB is taken as the x-axis of the shore base.

[0050] During the positioning inquiry process described above, the shore-based display and control system 100 sends a positioning inquiry signal, and when both the first processing unit 211 and the second processing unit 221 receive the positioning inquiry signal, the first processing unit 211 and the second processing unit 221 simultaneously start timing.

[0051] Suppose the diver's position is C(x,y,d), where d represents the diver's depth.

[0052] After the underwater processing unit 410 receives the positioning query signal, it sends the positioning response signal and depth information back to the first underwater acoustic reference beacon 210 and the second underwater acoustic reference beacon 220. After the first processing unit 211 and the second processing unit 221 parse the positioning response signal and the depth information respectively, they stop timing. At this time, the time delay obtained by the first underwater acoustic reference beacon 210 is recorded as the first time delay τ1, and the time delay obtained by the second underwater acoustic reference beacon 220 is recorded as the second time delay τ2.

[0053] Based on the average speed of sound c in the current sea area, the distance between points A and C is d1 = c × τ1, and the distance between points B and C is d2 = c × τ2.

[0054] Given A(x1,y1,z1), B(x2,y2,z2) and d1, d2, find (x,y,d).

[0055] The equation is as follows: (x-x1) 2 +(y-y1) 2 =d1 2 , (x-x2) 2 +(y-y2) 2 =d2 2 .

[0056] Thus, x and y can be calculated.

[0057] Since point C is located on the positive half of the y-axis, the system will filter out solutions on the negative half of the y-axis. In this way, the position of point C (x, y, d) is obtained and displayed and tracked in real time on the shore-based display and control system 100.

[0058] The shore-based monitoring and control system 100 can periodically activate positioning queries to track the diver's location and simultaneously acquire the diver's physiological information, detecting changes in physiological information in real time, greatly ensuring the diver's safety.

[0059] The key to transmitting a diver's physiological information and positioning response signal is the ability to process underwater acoustic signals. Accurately detecting underwater acoustic signals can effectively reduce the communication error rate, thereby improving the accuracy of information monitoring and positioning. Therefore, in some embodiments of this application, the processing of the received physiological information signal and positioning response signal by the first processing unit 211 is the key to improving the accuracy of information monitoring and positioning.

[0060] In this application, in order to improve the computing speed, the first processing unit 211 adopts FPGA multi-channel parallel computing to distinguish and demodulate the positioning response signal and the physiological information signal. That is, the positioning response signal detection and the physiological monitoring information signal detection are two separate detection channels, which are distinguished by different frame header signals. This fully utilizes the advantages of FPGA parallel computing, and the monitoring method flow of the two channels is consistent.

[0061] The following describes the processing process of the first processing unit 211 on the signal (positioning response signal or physiological monitoring information signal) output by the first underwater acoustic transducer 214 through the first receiving circuit 213.

[0062] The first processing unit 211 includes a signal sampling module (not shown), a preprocessing module (not shown), and a signal detection module (not shown).

[0063] The signal sampling module is used to receive the signal from the first underwater acoustic transducer 214 through the first receiving circuit 213, perform AD sampling, and output the sampled data.

[0064] The preprocessing module employs a pipelined approach, using a first-stage FFIO to buffer the sampled data. This prevents subsequent filtering without blocking or packet loss. The filtered data is then buffered again by a second-stage FFIO to output the preprocessed signal. This parallel buffer-filter-re-buffer pipeline architecture meets the low-latency requirements for underwater acoustic emergency communication and real-time positioning.

[0065] In this application, the signal detection process and the preprocessing process complement each other. During the signal detection process, the sampled data is preprocessed. The signals detected by the signal detection module are all signals that have been preprocessed by the preprocessing module.

[0066] The signal detection module involves performing a Fourier transform from the time domain to the frequency domain and an inverse Fourier transform from the frequency domain to the time domain on the preprocessed signal. During the transformation process, it is necessary to accurately detect the starting position of the preprocessed signal. To this end, the signal entry and exit sliding length is set when the preprocessed signal is buffered in the FIFO.

[0067] To accurately detect the preprocessed signal, the length L1 of the discrete-time sampling points selected during the Fourier transform needs to be greater than the length L2 of the preprocessed signal (i.e., the number of AD sampling points of the preprocessed signal). In order to ensure that no data is lost, the sliding length L is L1-L2 as described above.

[0068] For example, when the discrete time domain sampling point length L1=2048 and the preprocessed signal length L2=1524, L is 2048-1524=524, that is, the signal sliding length in and out of the FIFO buffer is 524 each time.

[0069] Thus, the preprocessed signal of length L2 can be transformed into a frequency domain signal using Fourier transform.

[0070] Then, the inverse Fourier transform is used to transform the preprocessed signal of length L2 into a time-domain signal, which is used to perform threshold detection on the data.

[0071] A threshold is set for the signal in advance. When the peak value of the time-domain signal obtained by the inverse Fourier transform is greater than the set threshold, it indicates that the current signal is the target signal, that is, the signal to be output by the first processing unit 211 to the shore-based display and control system 100 is identified.

[0072] The above-mentioned method of using a sliding signal ensures that the preprocessed signal is not lost, thereby achieving the goal of accurately detecting underwater acoustic signals.

[0073] In some embodiments of this application, in order to improve the accuracy of information acquisition, the signal sampling module includes a first amplification module, a filtering module, a second amplification module, and an ADC sampling module connected in sequence.

[0074] The first underwater acoustic transducer 214 generates a continuously changing analog electrical signal. To ensure the accuracy of signal acquisition, the signal output by the first underwater acoustic transducer 214 is first amplified by the first amplification module to reduce noise and boost the signal. Then, it is filtered by the filtering module to remove interference and improve signal purity. After that, the filtered signal is amplified by the second amplification module and then accurately matched to the ADC sampling module to ensure sampling accuracy. This sampling architecture can improve the signal-to-noise ratio, make the circuit more stable, and make the signal more faithful, providing accurate basic data for subsequent signal processing.

[0075] In some embodiments of this application, the filtering module described above can be a bandpass filter.

[0076] To ensure the accuracy of the positioning information, in addition to accurately acquiring the positioning response signal as mentioned above, it is also necessary to compensate for the first time delay τ1 and the second time delay τ2. This is because, as described above, timing stops after the positioning response signal is resolved from the first underwater acoustic reference beacon 210 and the second underwater acoustic reference beacon 220. (See [link to relevant documentation]). Figure 7 However, due to the different starting positions of the preprocessed signal in the discrete time domain sampling point length, there will be a period of empty signal time before the timing stops. Therefore, it is necessary to calculate this period of empty signal time (also known as the time delay deviation Δτ) to compensate for τ1 and τ2.

[0077] The signal detection module described above can detect the starting position of the preprocessed signal, see [link / reference]. Figure 7 It provides an example of a preprocessed signal in a discrete-time sampling point length L1.

[0078] Assume that the starting position of the preprocessed signal corresponds to the sampling point position x under the discrete time domain sampling point length L1, the discrete time domain sampling point length L1 = 2048, and the preprocessed signal length L2 = 1524. Therefore, the ending position of the preprocessed signal corresponds to the sampling point position x+1524 under the discrete time domain sampling point length L1. Thus, Δτ = (L1-L2-x)*fs, that is, the number of points corresponding to the empty signal time is the number of points from x+1524 to 2048. Calculate Δτ = (2048-(1524+x))*fs, where fs is the sampling frequency.

[0079] Calculate the first time delay after compensation τ1'=τ1-△τ and the second time delay after compensation τ1'=τ1-△τ.

[0080] When obtaining the diver's position C(x,y,d) as described above, τ1' should be replaced with τ1' and τ2' should be replaced with τ2 to ensure accurate acquisition of position information.

[0081] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by the present invention.

Claims

1. A diver physiological information monitoring and positioning system, characterized in that, include: Shore-based display and control system, which is used to display and monitor the physiological and positioning information of divers; The deck unit includes a first underwater acoustic reference beacon and a second underwater acoustic reference beacon, both of which are communicatively connected to the shore-based display and control system. The first underwater acoustic reference beacon includes a first processing unit, a first transceiver circuit communicatively connected to the first processing unit, and a first underwater acoustic transducer connected to the first transceiver circuit. The second underwater acoustic reference beacon includes a second processing unit, a second underwater acoustic transducer, and a second receiving circuit. The electrical signal output by the second underwater acoustic transducer is transmitted to the second processing unit through the second receiving circuit. Underwater systems, including: The physiological information acquisition module, which is installed on the diving suit itself, is used to acquire the diver's physiological information in real time. The underwater buoy, which integrates communication and navigation, includes an underwater processing unit, an underwater transceiver circuit connected to the underwater processing unit, a third underwater acoustic transceiver connected to the underwater transceiver circuit, and a depth information detection unit connected to the underwater processing unit. The physiological information acquisition module is connected to the underwater processing unit. A power module, which provides electrical energy to the electrical components in the underwater system; In use, the first and second underwater acoustic reference beacons are spaced at a preset distance to place the corresponding underwater acoustic transducers in the water. The diver's physiological information signals are received by the deck unit through the underwater system and sent to the shore-based display and control system for display. The process of locating the diver is as follows: Positioning query signals issued by the shore-based display and control system; After both the first and second underwater acoustic reference beacons receive the positioning query signal, the first underwater acoustic reference beacon sends a positioning query signal, and at the same time, both the first and second underwater acoustic reference beacons start timing. After receiving the positioning question and answer signal, the integrated communication and navigation underwater buoy transmits back the positioning response signal and the depth information detected by the depth information detection unit; The first and second underwater acoustic reference markers respectively analyze the location question and answer signals and stop timing; Based on the first time delay obtained from the first underwater acoustic reference beacon, the second time delay obtained from the second underwater acoustic reference beacon, the depth information, and the preset positions of the first and second underwater acoustic reference beacons, the first processing unit calculates the diver's location. The diver's location is displayed in real time on the shore-based display and control system.

2. The diver physiological information monitoring and positioning system according to claim 1, characterized in that, The power module includes a first power unit and a second power unit. The physiological information acquisition module is located on the diving suit and in contact with the diver's chest, and includes: Main control unit; A photoplethysmography (PPG) sensor, connected to the main control unit, is used to measure the diver's heart rate and blood oxygen saturation. A breathing rate sensor, which is connected to the main control unit, is used to measure the diver's breathing rate; The first power supply unit provides electrical energy to the electrical components in the physiological information acquisition module; The second power supply unit provides power to the electrical components in the integrated communication and navigation underwater buoy, which is also mounted on the diving suit and is positioned differently from the physiological information acquisition module.

3. The diver physiological information monitoring and positioning system according to claim 1, characterized in that, The depth information detection unit is a pressure sensor, and the underwater processing unit receives the pressure information fed back by the pressure sensor and converts it into depth information.

4. The diver physiological information monitoring and positioning system according to claim 1, characterized in that, The first processing unit uses FPGA multi-channel parallel computing to differentiate and modulate the positioning response signal and physiological information signal.

5. The diver physiological information monitoring and positioning system according to claim 4, characterized in that, The first processing unit further includes: The signal sampling module is used to receive the signal output from the first underwater acoustic transducer through the first transceiver circuit, perform AD sampling, and output the sampled data. The preprocessing module uses a first-level FFIO buffer to cache the sampled data and then performs data filtering. Finally, it outputs the preprocessed signal through a second-level FFIO buffer. The signal detection module is configured to perform the following: The preprocessed signal is subjected to a Fourier transform for time-domain to frequency-domain mapping. When performing time-domain to frequency-domain mapping using the Fourier transform, the length of the selected discrete time-domain sampling point is greater than the length of the preprocessed signal. When performing FIFO buffering in the preprocessing module, the signal in-and-out sliding length is the difference between the length of the discrete time-domain sampling point and the length of the preprocessed signal. The frequency domain data obtained by the transformation is then subjected to inverse Fourier transform for frequency-time domain mapping. If the transformed time-domain data meets the threshold determination condition, the data signal is output.

6. The diver physiological information monitoring and positioning system according to claim 5, characterized in that, The signal sampling module includes a first amplification module, a filtering module, a second amplification module, and an ADC sampling module connected in sequence. The first amplification module receives the signal output from the first underwater acoustic transducer.

7. The diver physiological information monitoring and positioning system according to claim 6, characterized in that, The filtering module is a bandpass filter.

8. The diver physiological information monitoring and positioning system according to claim 5, characterized in that, When the signal output by the first underwater acoustic transducer through the first receiving circuit is a positioning question-and-answer signal, the first time delay obtained from the first underwater acoustic reference and the second time delay obtained from the second underwater acoustic reference are compensated respectively, specifically as follows: Under time-frequency mapping, the time delay deviation Δτ is obtained based on the starting position of the preprocessed signal, the length L1 of the discrete time-domain sampling point, the length L1 of the preprocessed signal, and the sampling frequency fs. Based on the time delay deviation Δτ, the first time delay τ1 and the second time delay τ2 are compensated respectively; Using the compensated first time delay τ1', the compensated second time delay τ2', depth information, and the preset positions of the first and second underwater acoustic reference points, the first processing unit calculates the diver's location.

9. The diver physiological information monitoring and positioning system according to claim 8, specifically acquiring the time delay deviation Δτ, the compensated first time delay, and the compensated second time delay, includes: Obtain the starting position of the preprocessed signal corresponding to the sampling point position x under the length of the discrete time domain sampling points; Calculate the time delay deviation Δτ = (L1 - L2 - x) * fs; Calculate the first time delay after compensation τ1'=τ1-△τ and the second time delay after compensation τ1'=τ1-△τ.

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