TWI771706B - Signal capture system and signal capture method - Google Patents

Abstract

A signal capture method includes: synchronizing each of these wireless sensing devices with a clock based on a calibration signal via a sensing terminal controller; detecting a device to be tested by a sensor to obtain a sampling signal; obtaining a sampling timestamp based on the time when the sampling signal were retrieved; performing synchronization timing correction on the sensing terminal controller in each of these wireless sensing devices according to the sampling time stamp; and transmitting the sampling signal and the timestamp to a wireless receiving base station.

Description

Signal acquisition system and signal acquisition method

The present invention relates to a signal acquisition system and a signal acquisition method, in particular to a signal acquisition system and a signal acquisition method applied to a wireless sensing device.

With the rapid development of Industry 4.0, the Internet of Things, and big data analysis, intelligent applications are becoming increasingly important. The first step to achieve intelligent application is how to interpret the problem object in a digital way, and obtain a large amount of useful data to provide more social and industrial innovation in the follow-up. Among them, sensing technology is one of the ways to realize digitization. Nowadays, due to the advancement of process technology, various types of sensing devices can be used for different sensing objects. Common ones are accelerometers, which can be used to sense vibration, movement, and attitude, and gyroscopes, which can detect physical quantities related to rotation, and so on.

After obtaining digital data, the next key point is how to effectively centralize, organize and reuse the data. Therefore, data transmission technology also plays a key role. Especially in wireless data transmission, due to the advantages of no physical wiring, long distance and high mobility, the data collection of sensors is more convenient, resulting in the vigorous development of wireless sensor networks.

However, the wireless channel environment is complex, and the accuracy and integrity of data are relatively challenged by wireless data transmission, especially for high-speed sensors (such as accelerometers). In order to ensure data integrity, the current practice is to choose wireless communication protocol technologies with larger bandwidth, such as wireless local area network (Wi-Fi), but Wi-Fi itself has problems of interference and power consumption. If a power-saving and low-bandwidth wireless transmission protocol is adopted, when the wireless transmission rate is lower than the data sampling rate of the sensor, it will easily cause data distortion, which will also affect the interpretation inaccuracy of subsequent data analysis.

Therefore, how to ensure data integrity when the wireless transmission rate is lower than the sampling rate of the sensor has become one of the problems to be solved in the art.

In order to solve the above problems, an aspect of the present disclosure provides a signal acquisition system. The signal acquisition system includes a plurality of wireless sensing devices and a wireless receiving base station. Each wireless sensing device includes a sensing end controller, a sensor, and a sensing end wireless transceiver. The wireless receiving base station includes a plurality of base station wireless transceivers and a base station controller. The sensing end controller is used for clock synchronization of each of the wireless sensing devices according to a timing signal. The sensor is connected to a device under test, and the sensor detects the device under test to obtain a sampling signal. The sensing end controller obtains a sampling time stamp according to the time when the sampling signal is captured, and the sensing end controller in each wireless sensing device performs synchronization timing correction according to the sampling time stamp. The wireless transceiver of the sensing end receives the sampling signal from the controller of the sensing end, and transmits the sampling signal and the sampling time stamp. The wireless transceiver at the base station is used for receiving the sampling signal and the sampling time stamp from the transceiver at the sensing end. The base station controller is used for recombining the sampled signals to restore a sensing signal of the device under test.

Another aspect of the present invention is to provide a signal acquisition method suitable for a plurality of wireless sensing devices. The signal acquisition method includes: using a sensing end controller to synchronize each of the wireless sensing devices according to a timing signal; detecting a device to be tested by a sensor to obtain a sampling signal ; obtain a sampling time stamp according to the time of capturing the sampling signal; perform synchronization timing correction on the sensing end controller in each wireless sensing device according to the sampling time stamp; transmit the sampling signal and the sampling time stamp to a wireless receiving base station; and recombining the sampled signals by the wireless receiving base station to restore a sensing signal of the device under test.

To sum up, the signal acquisition system and signal acquisition method of the present invention can synchronize the clocks and timings of all wireless sensing devices, so that when the wireless transmission rate is lower than the sampling rate of the sensor, it can still efficiently transmit multiple The synchronized wireless sensing devices transmit sampling signals and sampling time stamps in turn, and the wireless receiving base station receives these sampling signals, reconstructs the sampling signals according to the sampling time stamps, and uses interpolation for the missing sampling signals to restore the sensing signal, and achieve the effect of ensuring the integrity of the sensing data.

The following descriptions are preferred implementations for completing the invention, and are intended to describe the basic spirit of the invention, but are not intended to limit the invention. Reference must be made to the scope of the following claims for the actual inventive content.

It must be understood that words such as "comprising" used in this specification are used to indicate the existence of specific technical features, values, method steps, operation processes, elements and/or components, but do not exclude the possibility of adding more technical features, values, method steps, job processes, elements, components, or any combination of the above.

The use of words such as "first", "second", "third", etc. in the claims is used to modify the elements in the claims, and is not used to indicate that there is a priority order, an antecedent relationship between them, or an element Prior to another element, or chronological order in which method steps are performed, is only used to distinguish elements with the same name.

Please refer to FIGS. 1-3. FIG. 1 is a block diagram illustrating a signal acquisition system 100 according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating an internal module of the sensing end controller CR0 according to an embodiment of the present invention. FIG. 3 is a schematic diagram illustrating an internal module of a base station controller BCR according to an embodiment of the present invention.

In one embodiment, the signal acquisition system 100 includes a plurality of wireless sensing devices 1 ˜N and a wireless receiving base station 20 . In one embodiment, the plurality of wireless sensing devices 1 ˜N can be regarded as belonging to a wireless sensing device group GP.

In one embodiment, the wireless sensing devices 1 ˜N are each connected to the device under test 30 , for example, by means of wired or wireless communication. The device to be tested 30 is an object, such as a machine, and the wireless sensing devices 1 to N are used to measure physical quantities such as temperature, vibration, etc. of the machine. In one embodiment, the wireless sensing devices 1 to N may all be used to measure the first physical quantity (eg, temperature) of the machine. In one embodiment, the wireless sensing devices 1-N may be partially (eg, the wireless sensing devices 1-11) used to measure the first physical quantity (eg, temperature) of the machine, and some (eg, the wireless sensing devices 12-N) Used to measure the second physical quantity (such as vibration) of the machine.

In one embodiment, each of the wireless sensing devices 1 ˜N includes a respective sensing end controller, a sensor, and a sensing end wireless transceiver. In one embodiment, each of the wireless sensing devices 1 ˜N further includes a respective storage device. For example, the wireless sensing device 1 includes a sensing-end controller CR0, a sensor SR0, a sensing-end wireless transceiver RV0, and a storage device ST0. For example, the wireless sensing device 2 includes a sensing end controller CR1, a sensor SR1, a sensing end wireless transceiver RV1 and a storage device ST0. For example, the wireless sensing device N includes a sensing end controller CRN, a sensor SRN, a sensing end wireless transceiver RVN, and a storage device STN.

In one embodiment, the sensors SR0-SRN include a temperature sensor, a pressure sensor, a vibration sensor, an optical sensor, an audio sensor, etc., and the sensors SR0-SRN can be all of them The same (eg, all temperature sensors) or partially the same (eg, half of the temperature sensors, the other half of the vibration sensor). In one embodiment, the sensing side controller (eg, the sensing side controller CR0 ) is electrically connected to the sensor (eg, the sensor SR0 ). In one embodiment, the sensor (eg, sensor SR0 ) is connected to the device under test 30 by a physical bond. In one embodiment, each wireless sensing device 1 ˜N is connected to the wireless receiving base station 20 .

In one embodiment, the sensing end controllers CR0 ˜CRN can be implemented as, for example, a microcontroller, a microprocessor, a digital signal processor, or an application-specific integrated circuit. specific integrated circuit, ASIC) or a logic circuit.

In one embodiment, please refer to FIG. 2 , the sensing end controllers CR0 ˜ CRN each include the same components. Taking the sensing end controller CR0 as an example, the sensing end controller CR0 includes a time synchronization module C1 . , a control parameter loading module C2 and a sensing data acquisition module C3, these modules are individually or collectively implemented as, for example, a microcontroller unit, a microprocessor, a digital signal processor, an application-specific integrated circuit or a logic circuit. In one embodiment, these modules may be implemented in software individually or together, and executed by the sensor-end controller CR0 (eg, a processor).

In one embodiment, the sensing-end wireless transceivers RV0 - RVN may be Wi-Fi transceivers, Bluetooth transceivers, or other devices capable of wireless communication.

In one embodiment, the storage devices ST0-STN may be ROM, flash memory, floppy disk, hard disk, optical disk, pen drive, magnetic tape, a database accessible through the network, or those skilled in the art may It is easy to think of storage media with the same function.

In one embodiment, the sensors SR0-SRN are used to detect the physical quantity (eg, temperature) of the device under test 30, the obtained physical quantity is called a sampling signal, and the sensors SR0-SRN transmit the sampling signal to their corresponding The sensing end controllers CR0~CRN, the sensing end controllers CR0~CRN can transmit the sampling signal to the corresponding storage devices ST0~STN for storage, or transmit the sampling signal to the corresponding sensing end wireless transceiver RV0~ The RVN waits for transmission to the radio receiving base station 20 . For example, the sensing end controller CR0 in the wireless sensing device 1 is electrically coupled to the sensor SR0, the storage device ST0 and the sensing end wireless transceiver RV0, respectively, and the sensor SR0 transmits the detected sampling signal to For the sensing end controller CR0, the sensing end controller CR0 can store the sampling signal in the storage device ST0, and can also transmit the sampling signal to the sensing end controller CR0 to prepare for transmitting the sampling signal to the wireless receiving base station 20.

In one embodiment, the time synchronization module (such as the time synchronization module C1) is used to synchronize the clock and timing of each wireless sensing device 1-N, and the time synchronization module (such as the time synchronization module C1) The wireless sensing devices 1 to N can be synchronized through, but not limited to, electrical connection.

In one embodiment, the wireless receiving base station 20 includes a plurality of base station-side wireless transceivers BV0 ˜BVK and a base station controller BCR. In an embodiment, the wireless receiving base station 20 further includes a storage device BST.

In an embodiment, the base station wireless transceivers BV0~BVK can be Wi-Fi transceivers, Bluetooth transceivers or other devices capable of wireless communication, and the base station wireless transceivers BV0~BVK can communicate with the wireless sensing device 1 through the base station wireless transceivers BV0~BVK. ~N to transmit and/or receive information.

In one embodiment, the base station controller BCR may be implemented as, for example, a microcontroller unit, a microprocessor, a digital signal processor, an application-specific integrated circuit, or a logic circuit.

In an embodiment, please refer to FIG. 3, the base station controller BCR includes a sensing signal configuration module B1 and a signal analysis module B2, in an embodiment, the base station controller BCR further includes a data processing module B3. Each or a combination of these modules is implemented, for example, as a microcontroller unit, a microprocessor, a digital signal processor, an application-specific integrated circuit, or a logic circuit. In one embodiment, these modules may be implemented in software individually or together, and executed by the base station controller BCR (eg, a processor).

In one embodiment, the storage device BST may be a read-only memory, a flash memory, a floppy disk, a hard disk, an optical disk, a pen drive, a magnetic tape, a database accessible through a network, or those skilled in the art can easily think of it. and storage media with the same function.

In one embodiment, the base station controller BCR is electrically coupled to the base station wireless transceivers BV0 ˜BVK and the storage device BST, respectively.

Please refer to FIG. 4 . FIG. 4 is a flowchart illustrating a signal acquisition method according to an embodiment of the present invention. The signal acquisition method can be implemented by the components shown in Figures 1 to 3.

In step 410, the sensing end controller (eg, the sensing end controller CR0) is used to synchronize the clock of each wireless sensing device (eg, the wireless sensing devices 1-N) according to a timing signal.

Each wireless sensing device 1-N includes a time synchronization function, which includes clock and timing. Clock synchronization can be synchronized through but not limited to electrical connection, and timing can be synchronized by radio wave but not limited to.

In one embodiment, when the signal acquisition system 100 is initialized, the wireless receiving base station 20 transmits the time calibration signal to the wireless sensing devices 1 ˜N, and the sensing end controllers CR0 ˜CRN corresponding to the wireless sensing devices 1 ˜N respectively. Reset the timing to zero.

In step 420, a sensor (eg, SR0) detects a device under test 30 to obtain a sampled signal.

In one embodiment, the sensors SR0 - SRN detect a device under test 30 to obtain a sampling signal (acceleration) of the device under test 30 respectively.

In one embodiment, taking the sensing-end controller CR0 as an example, the sensing data acquisition module C3 in the sensor (eg, SR0 ) is used to capture sampling signals and transmit them to the sensing-end controller CR0 .

In step 430, the sensing-end controller (eg, the sensing-end controller CR0) obtains a sampling time stamp according to the time of capturing the sampling signal.

In one embodiment, each of the sensing end controllers CR0 ˜CRN grabs the sampling timestamps in the wireless sensing devices 1 ˜N when the sampling signals are obtained, wherein the sampling timestamps refer to character strings or codes. The information is used to identify the date and time of the recording.

In step 440 , the sensing end controller (eg, the sensing end controller CR0 ) performs synchronization timing correction on the sensing end controllers CR0 ˜CRN in each wireless sensing device 1 ˜N according to the sampling time stamp.

Since the wireless sensing devices 1-N may be disturbed by the environment (such as radio waves) during sampling, the sampling time of each wireless sensing device 1-N is slightly wrong. The measurement terminal controllers CR0~CRN need to perform synchronization timing correction when starting the initialization.

In one embodiment, the base station controller BCR obtains a plurality of return times by subtracting the sampling time stamps obtained by all the wireless sensing devices 1-N from a test time stamp at the time when the wireless receiving base station 20 sends the test signal, respectively. , the sensing signal configuration module B1 calculates an average value of these return times, and according to the average value, the sensing terminal controllers CR0 ˜CRN in each wireless sensing device 1 ˜N are synchronously time-sequentially corrected, so that the sensing The end controllers CR0~CRN are aligned at the sampling time, and after the sampling time is aligned, each obtains the sampling signal and the sampling time stamp again.

In one embodiment, a sensor-side wireless transceiver (for example, the sensor-side wireless transceiver 1 ) receives a sampling signal from a sensor-side controller (for example, a sensor-side controller CR0 ), and transmits the sampling signal and sampling timestamp.

In one embodiment, each of the sensing-end wireless transceivers 1 ˜N respectively receives the sampling signals from the sensing-end controllers CR0 ˜CRN, and transmits the sampling signals and the Its sampling timestamp. For example, the sensor-side wireless transceiver 1 receives the sampled signal from the sensor-side controller CR0, transmits the sampled signal through the sensor-side wireless transceiver RV0, and obtains the sampling time stamp of the time point of the sampled signal.

In step 450, the base station wireless transceiver (eg, the base station wireless transceiver BV0) is used to receive the sampling signal and the sampling time stamp from the sensing end transceiver (eg, the sensing end wireless transceiver 1).

In one embodiment, the sensing signal configuration module B1 is used to configure one of the base station wireless transceivers BV0 to BVK to receive the signal. The sensing signal configuration module B1 can set the base station wireless transceivers BV0~BV1K to correspond to the sensing end wireless transceivers RV0~RVN, for example, the base station wireless transceiver BV0 is set to receive data from the sensing end wireless transceiver RV0 message. The base station wireless transceivers BV0 to BV1K and the sensing end wireless transceivers RV0 to RVN may be the same or different.

In step 460 , a base station controller BCR is used to recombine the sampled signals to restore a sensing signal of the device under test 30 .

In one embodiment, a signal analysis module B2 is used to sort the sampled signals according to the sampled time stamps from each of the wireless sensing devices 1-N, so as to reorganize the sampled signals, thereby restoring the sense of test signal.

Please refer to FIGS. 5A-5B. FIGS. 5A-5B are flowcharts illustrating a signal acquisition method according to an embodiment of the present invention. The signal acquisition method can be implemented by the components shown in Figures 1 to 3. The steps 512 to 520 are steps performed by each of the wireless sensing devices 1 to N. Therefore, in the following steps, the wireless transceiver 1 at the sensing end is used as an example for description.

In step 510, the sensing signal configuration module B1 in the base station controller BCR configures default parameters.

In one embodiment, the preset parameters include parameters such as a communication channel, a correspondence between the base station wireless transceivers BV0-BVK and the sensing-side wireless transceivers RV0-RVN, a transmission sequence, and/or a transmission state evaluation.

In step 511, the wireless sensing devices 1-N perform clock synchronization after receiving the timing signal.

In one embodiment, after the wireless sensing devices 1 ˜N receive the time calibration signal, the time synchronization function in the respective internal systems can be used for clock synchronization, so that the time of each wireless sensing device 1 ˜N is aligned.

In step 512, the wireless sensing device 1 loads the sampling configuration of the sensor SR0. The sampling configuration of the sensor SR0 is, for example, the sensor sampling interval time and the sampling signal acquisition time (for example, the sampling signal is collected for 1 hour).

In step 513, the wireless sensing device 1 loads the control parameters.

In one embodiment, the control parameter loading module C2 is used to set the round-robin time difference of each wireless sensing device 1-N to the sensing end wireless transceivers RV0-RVN of each wireless sensing device 1-N According to the round-robin time difference, the respectively captured sample signals and sample time stamps are transmitted.

In step 514, the wireless sensing device 1 starts to initialize, and the wireless sensing modules 1-N synchronize the timing.

In one embodiment, there is an initial delay time before the initialization is started and the sampling signal is captured. The initial delay time is subtracted by 1 from the Y sensors SR0~SRN (in this example, Y is equal to N+1), and then multiplied by 1. After M pieces of data are multiplied by a time constant ΔT, that is, (Y-1)*M*ΔT is the initial delay time. In an example, assuming that ΔT is 1 millisecond (ms), M is 1 data, and there are 3 sensors, the initial delay time is calculated as: (3-1)*1*1ms=2ms.

In step 515, the wireless sensing device 1 captures M digital sampling signals.

In one embodiment, the initial parameters detected by the sensor SR0 are analog data, and the initial parameters can be converted into digital sampling signals through an analog-to-digital device.

In step 516, the wireless sensing device 1 transmits the sampling signal through the wireless transceiver RV0 at the sensing end.

In step 517, the wireless sensing device 1 waits for the base station controller BCR to receive the sampling signal through the base station wireless transceiver BV0.

In step 518 , the wireless sensing device 1 determines whether the end time for capturing the sampling signal has been reached (for example, the sampling signal has been collected for one hour). If the wireless sensing device 1 determines that the end time for capturing the sampling signal has reached, the process proceeds to step 519 . If the wireless sensing device 1 determines that the end time of capturing the sampling signal has not been reached, that is, the current delay time is Y*M*ΔT, that is, 3*1*1ms=3ms, then go back to step 515 .

In one embodiment, the wireless sensing devices 1 to N include a first wireless sensing device (eg, the wireless sensing device 1 ) and a second wireless sensing device (eg, the wireless sensing device N). The sensing device and the second wireless sensing device receive an activation signal from the wireless receiving base station 20. After the first wireless sensing device transmits a first sampling signal and a first sampling time stamp to the wireless receiving base station 20, the first The two wireless sensing devices start to capture a second sampling signal and a second sampling time stamp. Wherein, before the first wireless sensing device transmits the first sampling signal and the first sampling time stamp to the wireless receiving base station 20, the second wireless sensing device is in a delay state. Therefore, by applying the round-robin mechanism to the sensors SR0~SRN, the data integrity can still be ensured when the wireless transmission rate is lower than the sampling rate of the sensor.

For example, the sensors SR0~SRN are all of the same type, the sampling speed is 250 bits per second, and the transmission time takes 1 second. When the wireless sensor device 1 needs to transmit 600 bits, because the sensor The timing of SR0~SRN has been completed, and the sensor SR0 is sampled (1~250 bit) first. At this time, other sensors SR1~SRN are in a delayed state. When the sensor SR0 is transmitting, the sensor SR0 cannot be sampled temporarily. , sampled by the sensor SR1 (251~500 bit) and transmitted. At this time, the sensor SR1 cannot sample temporarily during transmission, and the sensor SR2 will sample (501~600 bit) and transmit it. In one cycle, the data is transmitted through the synchronous timing sensors SR0~SR2.

In step 519, the wireless sensing device 1 transmits an end signal through the wireless transceiver RV0 at the sensing end.

In step 520, the wireless sensing device 1 waits for the base station controller BCR to receive the end signal through the base station wireless transceiver BV0.

In step 521, the base station controller BCR determines whether the reception of the end signal is completed. If the base station controller BCR determines that the reception of the end signal is completed, the process proceeds to step 522 . If the base station controller BCR determines that the reception of the end signal has not been completed, the process returns to step 520 .

In step 522, the base station controller BCR restores the sampled signal to the sensing signal through the signal analysis module B2.

In step 523, the base station controller BCR stores the sensing signal to the storage device BST.

Please refer to FIG. 6. FIG. 6 is a schematic diagram illustrating a signal acquisition method according to an embodiment of the present invention. For convenience of description, in FIG. 6 , the wireless receiving base station 20 , the wireless sensing device 1 and the wireless sensing device N are described below.

In step 610, the wireless receiving base station 20 configures the number of the sensing device, in step 611, the wireless sensor device 1 configures the number, and in step 612, the wireless sensor device N configures the number. Steps 610 to 612 are mainly for initial setting, so that the wireless receiving base station 20 can use the numbers of the wireless sensing device 1 and the wireless sensing device N to establish the base station wireless transceivers BV0 ~ BVK and the sensing end wireless transceivers RV0 ~ RVN corresponding relationship. In step 613, the wireless sensing device 1 configures an initial delay time for startup, in step 614, the wireless sensor device N configures an initial delay time for startup, and in step 615, the time synchronization module C1 causes the wireless sensor device 1 and the wireless The sensing device N performs clock synchronization.

In step 616, the wireless receiving base station 20 sends a test signal to all wireless sensing devices (in this example, the wireless sensing device 1 and the wireless sensing device N are represented), if the wireless sensing device 1 and the wireless sensing device N receive After receiving the test signal and sending a confirmation notification to the wireless receiving base station 20, the wireless receiving base station 20 transmits the activation signal. In step 617, the wireless sensing device 1 receives the test signal from the wireless receiving base station 20. In step 618, the wireless receiving The sensing device N receives the test signal from the wireless receiving base station 20. In step 619, the wireless sensing device 1 returns a sampling time stamp to the wireless receiving base station 20. In step 620, the wireless sensing device N returns a sampling time Poke to the wireless receiving base station 20. In step 621, the wireless receiving base station 20 evaluates the synchronization quality, the base station controller BCR subtracts all the sampling time stamps from a test time stamp of the test signal sent by the wireless receiving base station 20, and obtains a plurality of return times, and calculates the An average value of these return times, according to the average value, the sensing end controller CR0 of each wireless sensing device 1 and the sensing end controller CRN in the wireless sensing device N are adjusted for synchronization timing. In one embodiment, steps 616 to 621 may be performed multiple times to calibrate the timing more accurately.

In step 622, the wireless receiving base station 20 transmits an activation signal to the wireless sensing device 1 and the wireless sensing device N. In step 623, the wireless receiving base station 20 continues to wait for the sampling signal, and in step 624, the wireless sensing device 1 delays At the beginning, in step 625, the wireless sensing device N starts with a delay, and in step 626, the wireless sensing device 1 delays and ends. In some examples, the initial acquisition of the sampling signal may not necessarily have a delay, so after step 622, it can be Go directly to step 627.

In step 627, the wireless sensing device 1 starts to capture the sampling signal, in step 628, the wireless sensing device 1 transmits the sampling signal, in step 629, the wireless sensing device N delays and ends, in step 630, the wireless receiving The base station 20 receives the sampled signal. In step 631, the wireless sensing device N starts to acquire the sampled signal. In step 632, the wireless sensing device N starts to transmit the sampled signal. In step 633, the wireless receiving base station 20 receives the sampled signal. The delay of the wireless sensing device N between steps 625 and 629 is relatively long, in order to wait for the wireless sensing device 1 to capture and transmit the sampling signal before the wireless sensing device N captures and transmits the sampling signal.

Please refer to FIGS. 7-8. FIG. 7 is a schematic diagram illustrating a signal acquisition method according to an embodiment of the present invention. FIG. 8 is a schematic diagram illustrating a method for signal restoration of a sensing signal according to an embodiment of the present invention. In Figure 7, the original signal L1 is an analog signal, and the wireless sensing devices 1-3 will capture data from the original data L1 and convert it into a digital signal. The analog signal obtained by the sensor SR0 of the wireless sensing device 1 at the data acquisition point at time t1 will be converted into a digital signal P1, after the time constant ΔT (here, it is assumed that the number of data records M is 1, so the formula is, M*ΔT=ΔT), the analog signal obtained by the sensor SR1 of the wireless sensing device 2 at the data acquisition point at time t2 will be converted into a digital signal P2, and after the time constant ΔT, the wireless sensing device 3 The analog signal obtained by the sensor SR2 at the data capture point at time t3 will be converted into a digital signal P3, and then back to the analog signal obtained by the sensor SR0 of the wireless sensing device 1 at the data capture point at time t4 The signal will be converted to digital signal P4...and so on. It can be seen from this that the sensors SR0~SR2 are used in a round-robin manner. When acquiring data, the sensors SR0~SR2 can acquire data in turn, and the corresponding wireless transceivers RV0~RV2 of the sensing end transmit the data. , it is not necessary to wait until any one of the wireless sensing devices 1 to 3 transmits the data before transmitting the next piece of data. In the above example, when the wireless sensing device 1 transmits data, the wireless sensing device 2 can capture and transmit the data. When the transmission rate of the wireless sensing devices 1-3 is lower than the sampling rate of the sensors SR0-SR2 The integrity of the data can still be ensured when the speed is increased. If any data is lost during transmission, the lost data can also be supplemented by interpolation.

In one embodiment, when the sensors SR0-SR2 are used to sense the vibration of the machine, the sensing speed of the sensors SR0-SR2 is very fast, but the wireless transceivers at the sensing ends of the wireless transmission devices 1-3 transmit The rates RV0-RV2 are not fast enough, so the wireless transmission devices 1-3 transmit the sampled signals in turn, and finally the wireless receiving base station 20 reassembles the sampled signals according to the sampling time stamps to obtain the sensing signal.

In one embodiment, the sensors SR0-SR1 can be used to measure the sampled signals of temperature, and the sensor SR3 can be used to measure the sampled signals of vibration. In the same manner as described above, the wireless receiving base station 20 can use the sensors SR0-SR1 to measure the sampled signals. The sampling time stamps of the sensor SR2 reconstruct the temperature sampling signals to obtain temperature sensing signals, and reconstruct the vibration sampling signals according to the sampling time stamps of the sensor SR2 to obtain vibration sensing signals. In one embodiment, the data processing module B3 reads the sensing signal for further application.

In one embodiment, the digital signals P1-P9 can be regarded as sampling signals, and the line segment obtained by connecting the sampling signals P1-P9 in sequence is the sensing signal, which is described below with reference to FIG. 8 .

In Fig. 8, the original signal L1 is an analog signal, and the wireless sensing devices 1-3 will capture data from the original data L1 and convert it into a digital signal. Since the transmission rates of the wireless transceivers RV0-RV2 at the sensing end may vary according to various environmental influences, the wireless receiving base station 20 receives the sampling signals P1-P9 out of sequence, for example, the data (sampling signals) are received before the restoration in Figure 8. "2-2", "1-1", "3-3", "1-4", "2-5", "1-7", "3-6", "2-8" in order of reception ", "3-9", the representation of these symbols is that the value before "-" represents the code of the wireless sensing device, and the value after "-" represents the sampling timestamp (the smaller the value, the data that is sampled first ), for example, "3-6" represents that the data transmitted by the wireless sensing device 3 is transmitted at the sampling time stamp 6, and "2-5" represents that the data transmitted by the wireless sensing device 2 is transmitted at the sampling time stamp 5 Outgoing, among which, "1-4" are hollow dots, indicating that the wireless sensing device 1 did not transmit the data correctly at the sampling time stamp 4, and the data marked with "X" under the receiving order indicates that the receiving order is incorrect. The actual format of the sampling time stamp is determined by the internal system, and the numerical value is used here to illustrate it.

Therefore, the restored data (sampling signals) of the wireless receiving base station 20 arranged in time sequence are "1-1", "2-2", "3-3", and "4" (interpolation operation is performed by the adjacent two data Complementary value), "2-5", "3-6", "1-7", "2-8", "3-9", it can be seen that the value after "-" increases gradually, indicating that the According to the sampling time stamps, the sampling signals P1 to P9 are correctly reconstructed to obtain the sensing signals within this time interval. In one embodiment, the sensing signal can be regarded as storage data, which is stored in the storage device BST.

To sum up, the signal acquisition system and signal acquisition method of the present invention can synchronize the clocks and timings of all wireless sensing devices, so that when the wireless transmission rate is lower than the sampling rate of the sensor, it can still efficiently transmit multiple The synchronized wireless sensing devices transmit sampling signals and sampling time stamps in turn, and the wireless receiving base station receives these sampling signals, reconstructs the sampling signals according to the sampling time stamps, and uses interpolation for the missing sampling signals to restore the sensing signal, and achieve the effect of ensuring the integrity of the sensing data.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be determined by the scope of the appended patent application.

100: Signal acquisition system 1~N: Wireless sensing device 20: Wireless receiving base station 30: Device to be tested CR0~CRN: Sensing side controller SR0~SRN: Sensor ST0~STN, BST: storage device RV0~RVN: wireless transceivers at the sensing end GP: Wireless Sensing Device Group BCR: Base Station Controller BV0~BVK: base station wireless transceiver C1: Time synchronization module C2: Control parameters loaded into the module C3: Sensing data acquisition module B1: Sensing signal configuration module B2: Signal Analysis Module B3: Data processing module 410~460, 510~523, 610~633: Steps P1~P9: Sampling signal L1: original signal t1~t9: time ΔT: time constant M: number of data entries

FIG. 1 is a block diagram illustrating a signal acquisition system according to an embodiment of the present invention. FIG. 2 is a schematic diagram of an internal module of a sensor controller according to an embodiment of the present invention. FIG. 3 is a schematic diagram illustrating an internal module of a base station controller according to an embodiment of the present invention. FIG. 4 is a flow chart illustrating a signal acquisition method according to an embodiment of the present invention. FIGS. 5A-5B are flowcharts illustrating a signal acquisition method according to an embodiment of the present invention. FIG. 6 is a schematic diagram illustrating a signal acquisition method according to an embodiment of the present invention. FIG. 7 is a schematic diagram illustrating a signal acquisition method according to an embodiment of the present invention. FIG. 8 is a schematic diagram illustrating a method for signal restoration of a sensing signal according to an embodiment of the present invention.

410~460: Steps

Claims (18)

A signal acquisition system, comprising: A plurality of wireless sensing devices, each of which includes: a sensing end controller for synchronizing the clocks of each of the wireless sensing devices according to a timing signal; a sensor connected to a device under test, the sensor detects the device under test to obtain a sampling signal; wherein, the sensing end controller obtains a sampling time stamp according to the time when the sampling signal is captured, performing synchronization timing correction on the sensing end controller in each of the wireless sensing devices according to the sampling time stamp; and a sensor-side wireless transceiver that receives the sampling signal from the sensor-side controller, and transmits the sampling signal and the sampling time stamp; and A wireless receiving base station, including: a plurality of base station wireless transceivers for receiving the sampling signal and the sampling time stamp from the sensing transceiver; and a base station controller for recombining the sampled signals to restore a sensing signal of the device under test. The signal acquisition system as described in claim 1, wherein the base station controller further comprises: a sensing signal configuration module for configuring one of the base station wireless transceivers to receive the sampled signal; and A signal analysis module is used for sorting the sampling signals according to the sampling time stamps from each wireless sensing device to recombine the sampling signals. The signal acquisition system as described in claim 1, wherein the sensing end controller further comprises: a time synchronization module for synchronizing the clock and timing of each of the wireless sensing devices; A control parameter is loaded into the module for setting the round-robin time difference of the wireless sensing devices, and the wireless transceivers at the sensing ends of the wireless sensing devices transmit the respectively captured data the sampled signal and the sampled timestamp; and A sensing data acquisition module is used for acquiring the sampling signal. The signal acquisition system as described in claim 3, wherein the base station controller assigns the sampling time stamps obtained by all the wireless sensing devices to a test time when the wireless receiving base station sends the test signal. After the stamps are subtracted, a plurality of return times are obtained, and a sensing signal configuration module calculates an average value of the return times, and controls the sensing end in each of the wireless sensing devices according to the average value. synchronous timing correction. The signal acquisition system of claim 3, wherein the wireless sensing devices include a first wireless sensing device and a second wireless sensing device, the first wireless sensing device and the The second wireless sensing device receives an activation signal from the wireless receiving base station. After the first wireless sensing device transmits a first sampling signal and a first sampling time stamp to the wireless receiving base station, the second wireless sensing device transmits a first sampling signal and a first sampling time stamp to the wireless receiving base station. The sensing device starts to capture a second sampling signal and a second sampling time stamp. The signal acquisition system as described in claim 5, wherein before the first wireless sensing device transmits the first sampling signal and the first sampling time stamp to the wireless receiving base station, the second wireless sensing The device is in a delayed state. The signal acquisition system as described in claim 1, wherein each of the wireless sensing devices is connected to the wireless receiving base station. The signal acquisition system as described in claim 1, wherein the sensing end controller is electrically connected to the sensor. The signal acquisition system as described in claim 1, wherein the sensor is connected to the device under test by a physical combination. A signal acquisition method is applicable to a plurality of wireless sensing devices, the signal acquisition method includes: synchronizing each of the wireless sensing devices by a sensing end controller according to a timing signal; Detecting a device under test by a sensor to obtain a sampling signal; obtaining a sampling time stamp according to the time when the sampling signal was captured; performing synchronization timing correction on the sensing end controller in each of the wireless sensing devices according to the sampling time stamp; sending the sampling signal and the sampling time stamp to a wireless receiving base station; and The sampling signals are reconstructed by the wireless receiving base station to restore a sensing signal of the device under test. The signal acquisition method described in item 10 of the scope of the application further includes: configuring one of the plurality of base station wireless transceivers in the wireless receiving base station to receive the sampled signal; and The sampled signals are sorted according to the sampling time stamps from each wireless sensing device to reassemble the sampled signals. The signal acquisition method described in item 10 of the scope of the application further includes: clock synchronization and timing synchronization of each of the wireless sensing devices; setting a round-robin time difference of the wireless sensing devices, and the wireless transceivers at the sensing ends of the wireless sensing devices transmit the sampled signal and the sampling time stamp acquired respectively according to the round-robin time difference; and Capture the sampled signal. The signal acquisition method described in Item 12 of the scope of the patent application further includes: After subtracting the sampling time stamps obtained by all the wireless sensing devices from a test time stamp of the test signal sent by the wireless receiving base station, a plurality of return times are obtained, and an average of the return times is calculated value, and the sensing end controller in each of the wireless sensing devices performs synchronization timing correction according to the average value. The signal acquisition method of claim 12, wherein the wireless sensing devices include a first wireless sensing device and a second wireless sensing device, the first wireless sensing device and the wireless sensing device The second wireless sensing device receives an activation signal from the wireless receiving base station. After the first wireless sensing device transmits a first sampling signal and a first sampling time stamp to the wireless receiving base station, the second wireless sensing device transmits a first sampling signal and a first sampling time stamp to the wireless receiving base station. The sensing device starts to capture a second sampling signal and a second sampling time stamp. The signal acquisition method as described in claim 14, wherein before the first wireless sensing device transmits the first sampling signal and the first sampling time stamp to the wireless receiving base station, the second wireless sensing The device is in a delayed state. The signal acquisition method as described in claim 10, wherein each of the wireless sensing devices is connected to the wireless receiving base station. The signal acquisition method as described in claim 10, wherein the sensing end controller is electrically connected to the sensor. The signal acquisition method as described in claim 10, wherein the sensor is connected to the device under test by a physical combination.

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