A data sampling apparatus and time-synchronised data sampling system for sampling data across a plurality of sensors

Abstract

A data sampling apparatus connectable to a sensor. The data sampling apparatus includes a data sampling controller, an analog-to-digital converter (ADC) and a GPS receiver connected to the data sampling controller. The ADC is configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals and the GPS receiver is configured to generate Pulse-Per-Second (PPS) pulses and time data. The data sampling controller collects the data and generates time accurate data packets.

Description

A DATA SAMPLING APPARATUS AND TIME-SYNCHRONISED DATA SAMPLING SYSTEM FOR SAMPLING DATA ACROSS A PLURALITY OF SENSORSTECHNICAL FIELD[1] The present invention relates to a data sampling apparatus and system for high-speed data measurement and accurate time synchronization across a geographically dispersed set of sensors.BACKGROUND[2] Any references to methods, apparatus or documents of the prior art are not to be taken as constituting any evidence or admission that they formed, or form part of the common general knowledge.[3] Traditionally, data acquisition systems have relied on synchronized clocks or time-stamping protocols to ensure accurate timekeeping. However, these methods often face challenges in achieving high accuracy and maintaining synchronization over a large number of distributed devices, especially in situations where network latency or varying environmental conditions can affect the system's performance.[4] Another issue faced by conventional data acquisition systems is the reliable storage and transmission of collected data. These systems typically use standard storage devices and rely on stable network connections for data transmission. However, they often struggle with limited storage capacity or intermittent connectivity, leading to potential data loss or delays in data transmission to the cloud or other processing platforms.[5] Some solutions use traditional data acquisition systems. These systems often use synchronized clocks or time-stamping protocols to ensure accurate timekeeping, with GPS-based time synchronization occasionally integrated for higher accuracy. To store and transmit collected data, these systems typically use standard storage devices and rely on stable network connections for data transmission. However, these systems face challenges with maintaining synchronization across distributed devices, particularly in environments with network latency or varying conditions. Moreover, they often struggle with limited storage capacity and intermittent connectivity, leading to potential data loss or transmission delays.[6] GPS-based time synchronization has been explored as a potential solution to address timing issues. While GPS time synchronization provides a high level of accuracy, integrating it with data acquisition systems can be complex and often requires specialized hardware and software components.[7] Moreover, many existing systems lack the ability to handle continuous data sampling and buffering effectively, making them unsuitable for applications that require uninterrupted data collection and analysis.[8] Therefore, there is a need for a high-speed data measurement system that can accurately synchronize time across a distributed sum of standalone devices, handle continuous data sampling, and provide reliable data storage and transmission capabilities.SUMMARY OF INVENTION[9] In an aspect, the invention provides a data sampling apparatus connectable to a sensor, the data sampling apparatus comprising:a data sampling controller; an analog-to-digital converter connected to the data sampling controller and configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals; a global positioning system receiver connected to the data sampling controller and configured to generate Pulse-Per-Second (PPS) pulses and time data; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals; receive the digital data signals from the ADC and record a first clock cycle number of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected; receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the data sampling controller upon receipt of the PPS pulse; and generate a data packet including time data from the GPS receiver, first and second clock cycle numbers and the digital data signals.

[0010] Preferably, the data sampling controller is further configured to store the data packet.

[0011] Preferably, the data sampling controller is further configured to determine a timestamp of each digital data signal of the data packet based on the PPS pulses, time data, and first and second clock cycle numbers.

[0012] Preferably, a clock of the data sampling controller is connected to a counter. The counter counts the clock cycles of the clock and records the clock cycle number upon receipt of the digital data signals from the ADC and again upon receipt of the PPS pulses from the GPS receiver.

[0013] Preferably, the data sampling apparatus is connected to one or more sensors.

[0014] Advantageously, the invention provides for accurate and synchronised measurement in the time domain across two or more sensing points where sensors are located and connected to multiple data sampling apparatus. As such, the time domain (or temporal effects) can effectively be ignored allowing for analysis of events on an electrical line (or in the propagation medium) without needing to consider distance or propagation between the two or more sensing points.

[0015] In another aspect, the invention provides a pair of data sampling apparatus each connectable to a corresponding sensor, each data sampling apparatus comprising: a data sampling controller; an analog-to-digital converter connected to the data sampling controller and configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals; a global positioning system receiver connected to the data sampling controller and configured to generate Pulse-Per-Second (PPS) pulses and time data; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals;receive the digital data signals from the ADC and record a first clock cycle number of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected; receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the data sampling controller upon receipt of the PPS pulse; and generate a data packet including time data from the GPS receiver, first and second clock cycle numbers and the digital data signals; wherein each data packet is synchronised in time to provide a timestamp for each digital data signal.

[0016] In another aspect, the invention provides a time-synchronised data sampling system for sampling data across a plurality of sensors, the time synchronised data sampling system comprising: a plurality of data sampling apparatus as described above, each data sampling apparatus being connectable to a sensor; a central controller in digital communication with each data sampling apparatus and configured to receive data packets from each data sampling apparatus and determine a timestamp for each digital signal in each data packet.

[0017] Preferably, each data packet is synchronised in time.

[0018] Preferably, the central controller is configured to determine characteristics of the analog data signals and / or characteristics of the propagation medium from the data packets.

[0019] Preferably, the central controller is configured to:calculate an electrical distance between two sensors; and / or calculate a length of a powerline, and correlate the length against schematics to determine a circuit configuration; and / or calculate a change in the length of a powerline in response to changes in temperature; and / or calculate a nature of propagation of external signals (such as lightning strikes) in power lines within a predetermined radius; and / or determine a type of one or more electrical devices in a circuit based on a presence of external signals detected by sensors subsequent to traveling through the one or more electrical devices.

[0020] Preferably, the central controller is part of one of the plurality of data sampling apparatus.

[0021] Preferably, the ADC collects 112 analog data signals that are converted into 112 corresponding digital data signals, wherein each data packet includes the 112 digital data signals.

[0022] In another aspect, the invention provides a time-synchronised data sampling system for sampling data across a plurality of sensors, the time synchronised data sampling system comprising: a plurality of data sampling apparatus, a global positioning system configured to generate Pulse-Per-Second (PPS) pulses and time data; wherein each data sampling apparatus is connectable to a sensor located in a propagation medium and comprises:a data sampling controller; and an analog-to-digital converter connected to the data sampling controller and configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals; receive the digital data samples from the ADC and record a first clock cycle number of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected; receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the data sampling controller upon receipt of the PPS pulse; and generate a data packet based on the PPS pulses, time data, first and second clock cycle numbers and digital data signals; and a central controller configured to receive the data packets from each data sampling apparatus and determine a timestamp for each digital signal in each data packet.

[0023] Preferably, the central controller is configured to determine one or more signal correlations based on the digital data signals.

[0024] In another aspect, the invention provides a method for time-synchronised data sampling from one or more sensors, the method comprising:acquiring a plurality of analog data signals travelling through a propagation medium from a sensor; converting the plurality of analog data signals into digital data signals; recording a first clock cycle number of a data sampling controller based on a time a final analog data sample of the plurality of analog data samples was collected; receiving pulse-per-second pulses and time data from a GPS receiver; recording a second clock cycle number of the data sampling controller upon receipt of the PPS pulse and the time data; and generating a data packet including the time data from the GPS receiver, first and second clock cycle numbers and the digital data samples.

[0025] Preferably, the method further includes storing the data packet.

[0026] Preferably, the method further comprises acquiring a plurality of analog data signals travelling through the propagation medium from a plurality of sensors. Preferably, the method further comprises generating a plurality of data packets corresponding to the plurality of sensors. Preferably, method further comprises determining characteristics of the analog data signals and / or characteristics of the propagation medium from the data packets.

[0027] Preferably, the data sampling apparatus further comprises a first memory for storing the data packets. Preferably, the first memory is either SRAM (static random access memory), DRAM (dynamic random access memory) or flash memory. Preferably, the data sampling apparatus further comprises a second memory configured to store data packets when the first memory is full.

[0028] Preferably, the system further comprises a plurality of sensors. More preferably, the system further comprises a plurality of distributed sensors. Preferably,each sensor is independent of every other sensor or the plurality of sensors are unnetworked.

[0029] Preferably, the sensor comprises a shunt resistor connected to a main powerline; a hall effect sensor connected to an electrical wire; or a strain gauge connected to a water pipe.

[0030] Preferably, the method further includes determining a timestamp of each digital data signal of the data packet based on the PPS pulses, time data, and first and second clock cycle numbers.

[0031] In an aspect, the invention provides a data sampling apparatus connectable to a sensor, the data sampling apparatus comprising: a data sampling controller; an analog-to-digital converter connected to the data sampling controller and configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals; a global positioning system receiver connected to the data sampling controller and configured to generate Pulse-Per-Second (PPS) pulses and time data; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals; receive the digital data signals from the ADC and record a first clock cycle number of a clock of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected;receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the clock of the data sampling controller upon receipt of the PPS pulse; and generate a data packet including time data from the GPS receiver, first and second clock cycle numbers and the digital data signals.BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:Figure 1 is a block diagram of a data sampling apparatus according to an embodiment of the present invention;Figure 2 illustrates a data packet generated by the data sampling apparatus;Figure 3 is a block diagram illustrating the flow of data in the system;Figure 4 illustrates a time-synchronised data sampling system for sampling data across a plurality of sensors according to one embodiment of the present invention;Figure 5 illustrates a time-synchronised data sampling system for sampling data across a plurality of sensors according to another embodiment of the present invention; andFigure 6 illustrates an example of the receipt of data signals at certain clock cycles of the FPGA used to determine the data timestamps.DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0033] Figures 1 to 6 illustrate a data sampling apparatus (DSA) 10 and a time- synchronised data sampling systems 100, 200 for sampling data across a plurality of sensors.

[0034] Embodiments of the invention relate to a system for taking high-speed measurements of a signal traveling through a propagation medium, applying at the sensor accurate and continuous time synchronization to a global clock using embedded processors and GPS technology, and allowing back propagation tracing to derive and infer the nature of both the signal source and the propagation medium.

[0035] The propagation medium is any physical material or substance through which signals travel. The propagation medium can be a solid, liquid, or gas, and its properties affect the behaviour of the wave or signal as it travels through it. By precisely measuring the time signals arrive at various points in the medium the medium and the event triggering the signal can be described. The propagation medium may be electrical circuits, physical structures (such as walls or objects), or air, for example.

[0036] In Figure 1, a data sampling apparatus 10 connectable to a sensor 15 is shown. The data sampling apparatus 10 may be connectable to one or more sensors.

[0037] In some embodiments, and in use, the data sampling apparatus is connected to one or more sensors 15.

[0038] The data sampling apparatus 10 includes a data sampling controller 20, an analog-to-digital converter (ADC) 30 connected to the data sampling controller 20 and a global positioning system receiver 40 connected to the data sampling controller 20.

[0039] The data sampling controller 20 may take the form of a microcontroller.

[0040] The data sampling controller 20 includes a field programmable gate array (FPGA) 21, an ARM processor 21a, a clock 24 that may otherwise be referred to as an external clock and a counter 24a. The FPGA 21 and ARM processor 21a may be combined in a System-On-Chip (SOC) arrangement in some embodiments. The counter 24a may be implemented within the FPGA 21.

[0041] The clock 24 provides the timing signal for the above components. The clock 24 may be configured to run at 100MHz.

[0042] The ADC 30 is, in use, connected to the sensor (or sensors) and configured to continuously sample analog data signals travelling through a propagation medium from the sensor 15 and convert the analog data signals into digital data signals. The ADC 30 may be triggered by a divisor on the clock 24. In an example, the ADC 30 may be triggered by a divisor on the external clock 24 running at 100MHz. The divisor reduces the frequency of the external clock 24 to 100kHz for the ADC 30.

[0043] The divisor reduces the frequency of the external clock to 100kHz for the ADC.

[0044] In embodiments where the ADC 30 is connected to multiple sensors (where the number of sensors is n) via multiple channels (where the number of channels is also n) in the ADC 30, the ADC 30 sequentially samples a signal from each channel such that every nth sample (signal) corresponds to the number of channels (n).

[0045] The above configuration provides for insights and analysis of multiple metrics per device, for metrics that are correlated, for example, one could measure both current and voltage of a wire and have the power usage of the wire.

[0046] The GPS receiver 40 is configured to generate Pulse-Per-Second (PPS) pulses 41 and time data 42 that are provided to the data sampling controller 20.

[0047] In use, the data sampling controller 20 is configured to control the ADC 30 to collect a plurality of analog data signals 27 from the sensor 15 and convert the plurality of analog data signals 27 to digital data signals 28.

[0048] The data sampling controller 20 may control the ADC 30 using the clock 24. In some embodiments, the clock 24 is running at 100MHz. The ADC 30 is triggered by a divisor of this clock 24, resulting in a 100kHz sampling rate. The clock 24 is connected to a counter 24a that increments with each clock cycle.

[0049] Once the ADC 30 takes 112 samples, the counter 24a records its value, which is used to timestamp these samples. The counter 24a also records its value upon receiving a Pulse-Per-Second (PPS) signal from the GPS receiver 40. This PPS signal serves as a precise timing reference.

[0050] The counter thus has two triggers: (1) The first trigger occurs when a set number of ADC samples (112) have been taken, prompting the counter to record the clock cycle value; and (2) The second trigger occurs whenever the PPS signal arrives, prompting the counter to record the clock cycle value at that precise moment.

[0051] This dual-trigger approach allows for accurate positioning of ADC samples relative to the PPS signal, ensuring that each sample is precisely timestamped according to global time.

[0052] Once the data sampling is complete, the digital data signals 28 are sent to memory 22 of the ARM processor via DMA 22a (direct memory access) (see Figure 3).

[0053] The data sampling controller 20 then receives the digital data signals 28 from the ADC 30 and records a first clock cycle number 25 of the clock 24 of the data sampling controller 20 (determined by the counter 24a in the FPGA 21) based on a time a final analog data signal 27 of the plurality of analog data signals 27 was collected.

[0054] Additionally, the data sampling controller 20 receives the PPS pulses and time data from the GPS receiver 40 and records a second clock cycle number 26 of the clock 24 of the data sampling controller 20 (also determined by the counter 24a in the FPGA 21) upon receipt of the PPS pulse 41 and the corresponding time data 42.

[0055] Advantageously, the clock 24 positions the ADC samples relative to the PPS pulses, accurate to 1 / clock speed seconds.

[0056] Once the above information has been received, the data sampling controller 20 generates a data packet 23 including the time data from the GPS receiver 40, first and second clock cycle numbers 25, 26 and the digital data signals 28 and stores the data packet 23 in memory 50.

[0057] From the data packet 23, a timestamp of each digital data signal of the data packet 23 based on the PPS pulses, time data, and first and second clock cycle numbers 25, 26 can be determined. This can be performed across multiple data packets and multiple data sampling apparatus to provide for analysis of signals across multiple sensors.

[0058] The data packet 23 is, in some embodiments, a 256-byte packet (illustrated in Figure 2), although the data packet 23 can be of any size. Regardless of the size of the data packet 23, the data packet 23, in some embodiments, contains the most recent GPS time transmitted to the data sampling controller, the clock cycle number when the most recent PPS was received by the data sampling controller, the clock cycle number when the analog data signals were collected and the digital data signals.

[0059] As mentioned above, using the PPS pulses as a precise timing signal, time data, and first and second clock cycle numbers, the timestamp of each digital data signal can be reliably and accurately determined.

[0060] Advantageously, the invention provides for accurate and synchronised measurement of the time domain across two or more sensing points where sensors are located and connected to multiple data sampling apparatus to allow for time domain analysis. As such, the time domain (or temporal effects) can effectively be ignored allowing for analysis of events on an electrical line (or in the propagation medium) without needing to consider distance or propagation between the two or more sensing points.

[0061] Further advantageously, embodiments of the invention use the GPS receiver 30 to synchronize the local clocks of the data sampling controllers 20. The PPS pulses from the GPS receiver 30 are received by the FPGA (Field-Programmable Gate Array) of the data sampling controller 20, which acts as a time synchronization module.

[0062] In summary, the synchronisation is achieved as follows.

[0063] The GPS receiver 30 receives highly accurate time information from the GPS satellite system, which is derived from atomic clocks on the GPS satellites. The GPSreceiver 30 generates Pulse-Per-Second (PPS) pulses at the beginning of each second, providing a precise timing reference for synchronization.

[0064] The FPGA of the data sampling control 20 receives these PPS pulses from the GPS receiver 30.

[0065] The FPGA continuously samples data from the connected sensors to generate data packets that contain the sampled data along with corresponding timestamps. These timestamps are based on the clock numbers of the FPGA, which is synchronized with the GPS time reference determined from the PPS pulses. As a result, the data packets accurately reflect the time at which each sample was taken.

[0066] By incorporating the precise time reference from the GPS receiver 30, the described invention ensures accurate synchronization and timestamping of the sampled data. This synchronization allows for precise correlation and analysis of the data collected from the distributed sensors in the system.

[0067] An example will be provided below with reference to Figure 6. The red dotted lines are the samples, the black dotted lines are the clocks of the FPGA of the data sampling controller.

[0068] Each sample taken by the ADC is separated by a fixed number of clock cycles generated by the FPGA. For example, if the samples are consistently 5 clocks apart as shown.

[0069] By analyzing the clock cycles and sample positions, specific clock numbers can be assigned. For instance, the first clock cycle number (as described herein) from Figure 6 would be 30 because sample 6 occurs at clock 30. The second clock cycle number would be 14, which is the first FPGA clock number (the second clock number described herein) after the PPS (Pulse-Per-Second) signal is received.

[0070] These clock numbers (the first and second clock numbers) provide the necessary information to accurately timestamp each sample. Considering that each sample is 5 clocks apart, the clock numbers for all 6 samples in the packet would be 30, 25, 20, and so on, down to 0. Additionally, by knowing the clock number of the FPGA when the PPS pulse arrived (in this case, 14) and the clock number of a specific sample (e.g., sample 3 at clock 15), the "clock differential" to the PPS can be determined.

[0071] The frequency of the clock of the FPGA can be determined by comparing the clock numbers of two consecutive PPS pulses (e.g., 62 and 14). In this example, the frequency is calculated as 48Hz, which corresponds to a duration of 0.021 seconds per clock.

[0072] By combining the clock differential with the clock frequency, the arrival time of each sample relative to the PPS pulse can be determined. Since the PPS pulse represents the exact global start of a second (within error of GPS), knowing when a specific sample (e.g., sample 3) was taken becomes possible. Thus, within a single data packet, each data signal can be accurately timestamped. This timestamp is applicable to any device worldwide.

[0073] In a preferred embodiment, the ADC 30 collects 112 analog data signals that are converted into 112 corresponding digital data signals, wherein each data packet 23 includes the 112 digital data signals. However, the number of analog data signals can be varied and could be any number.

[0074] 112 digital data signals were selected as an optimal size to provide a 256 byte packet (which is a common maximum transfer size) where each of the 122 signals is 2 bytes. This provides space for 32 bytes of timing data.

[0075] In some embodiments where memory can accept greater than 256 bytes at a time, the number of samples (signals) can be increased to improve performance and reduce the amount of overhead (timing data) per packet, thereby increasing efficiency.

[0076] The data sampling apparatus 10 includes at least a first memory 51 for storing the data packets 23. The first memory 51 may be of any suitable type but is preferably one of SRAM (static random access memory), DRAM (dynamic random access memory) or flash memory.

[0077] In some embodiments, the system includes a single Dynamic Random-Access Memory (DRAM) module, as data persistence may not be required for certain applications. This DRAM module is accessible concurrently by both cores of an ARM microprocessor. The first core is responsible for collating incoming signals into a single packet, while the second core manages the transmission of this data via a communications module. The DRAM module is logically partitioned into two sections, allowing the system to fill one section until capacity is reached before transitioning to the other section. This arrangement ensures continuous data processing and seamless transmission operations.

[0078] In some embodiments, the data sampling apparatus 10 includes a second memory 52 configured to store data packets when the first memory 51 is full. The second memory 52 may be of the same type of memory as the first memory 51 or a different type of memory. This dual-flash setup provides a large data buffer in case of data connection issues and improves system reliability.

[0079] In some embodiments, the invention takes the form of a time-synchronised data sampling system 100 for sampling data across a plurality of sensors.

[0080] The system 100 includes a plurality of data sampling apparatus 10 as described above where each data sampling apparatus 10 is connectable to one of a plurality of sensors 15.

[0081] The plurality of sensors 15 are, in some embodiments, distributed sensors where each sensor 15 is independent of every other sensor or the plurality of sensors are un-networked. That is, each sensor operates independently of every other sensor of the plurality of sensors.

[0082] The sensor or sensors can include any type of sensor that generates an analog data signal in response to an input. In some embodiments, the sensor comprises a shunt resistor connected to a main powerline to measure electrical current; a hall effect sensor connected to an electrical wire to measure a magnetic field; a strain gauge connected to a water pipe to measure mechanical strain or deformation; an ammeter for measuring current or a voltmeter for measuring voltage.

[0083] As an example, embodiments of the invention may be connected to a number of strain gauges located at various points in a water network which would provide for instantaneous pressure and vibration measurements at each point, and the mapping of the flow and usage of water in a similar way to electricity using simple fluid dynamics.

[0084] The system 100 also includes a central controller 60 in digital communication with each data sampling apparatus 10 and configured to receive data packets from each data sampling apparatus 10 and determine one or more signal correlations based on the digital data signals. The digital communication between the central controller 60 and each data sampling apparatus 10 may be provided by a wireless data connection. Alternatively, the data sampling apparatus 10 may be physically connected to the central controller 60.

[0085] The data packets generated by the various data sampling apparatus 10 are synchronised in time. More particularly, each data packet is synchronised in time to provide a timestamp for each digital data signal.

[0086] The central controller 60 may include a processing assembly for receiving and processing the data packets 23.

[0087] The central controller 60 is configured to determine characteristics of the analog data signals and / or characteristics of a source of the analog data signals and / or characteristics of the propagation medium from the data packets 23. The characteristics may include a location of the source of the analog data signals or a configuration of a circuit, for example.

[0088] In some embodiments, the central controller 60 is configured to calculate an electrical distance between two sensors. This may be calculated using a time difference between data packets from a first data sampling apparatus and a second data sampling apparatus.

[0089] Additionally or alternatively, the central controller is configured to calculate a length of a powerline, and correlate the length against schematics to determine a circuit configuration.

[0090] Additionally or alternatively, the central controller is configured to calculate a change in the length of a powerline in response to changes in temperature.

[0091] Additionally or alternatively, the central controller is configured to calculate a nature of propagation of external signals (such as lightning strikes) in power lines within a predetermined radius.

[0092] Additionally or alternatively, the central controller is configured to determine a type of one or more electrical devices in a circuit based on a presence of externalsignals detected by sensors subsequent to traveling through the one or more electrical devices.

[0093] In some embodiments, using the data packets obtained from multiple data sampling apparatus, the following can be determined: position of objects and people in a warehouse, building or property based on sound generated by the object or person / people; isolating the sound from single objects in a noisy environment; and detecting and interpreting the propagation of vibration sources in a physical structure, such as a pump, for example.

[0094] While the central controller 60 is illustrated as a separate device, in some embodiments, the central controller may be part of one of the data sampling apparatus or the data sampling controller of one of the data sampling apparatus may be nominated as the central controller.

[0095] In another embodiment, there is provided a time-synchronised data sampling system 200 for sampling data across a plurality of sensors 15. The system 200 is substantially similar to the system 100. However, in system 200, a single GPS receiver 40 is provided that communicates with a plurality of data sampling apparatus 11. The data sampling apparatus 11 each include a data sampling controller 20 (a described above) and an analog-to-digital converter 30 (as described above) connected to the data sampling controller 20 and configured to continuously sample analog data signals travelling through a propagation medium from the sensor / s 15 and convert the analog data signals into digital data signals. The operation and configuration of the data sampling controller 20 in this embodiment is the same as the earlier embodiment.

[0096] In the following discussion, a method for time-synchronised data sampling across one or more sensors which the data sampling controllers and central controller are configured implement will be explained.

[0097] As previously discussed in overview, a distribution of sensors 15 is provided.

[0098] A data sampling apparatus 10 is connected to each sensor 15 and acquires a plurality of analog data signals travelling through a propagation medium from a corresponding sensor 15.

[0099] The plurality of analog data signals for each data sampling apparatus 10 are then converted into digital signals by their corresponding ADC 30.

[0100] A first clock cycle number 25 of the data sampling controller 20 based on a time a final analog data sample of the plurality of analog data samples was collected is recorded in memory 50.

[0101] Pulse-per-second (PPS) pulses and time data are then received by the data sampling controller / s 20 from the GPS receiver 40 and a second clock cycle number of the data sampling controller 20 upon receipt of the PPS pulse is recorded.

[0102] The data sampling controller 20 then generates a data packet 23 including the time data from the GPS receiver, first and second clock cycle numbers and the digital data samples stores the data packet 23 in memory 50.

[0103] With reference to Figure 4, the plurality of sensors 15 and data sampling apparatus 10 are distributed in a space 2 about a source 5 in the form of an object generating noise.

[0104] The sensors 15 take the form of microphones.

[0105] In use, the sensors 15 detect the noise that travels through the air (the propagation medium) and generate analog data signals that represent the detected noise. The data sampling apparatus 10 connected to the sensors 15 then sample the analog data signals and generate digital data signals. In accordance with the methodologies described elsewhere, each data sampling apparatus generates a data packet that is communicated to the central controller 60. These data packets can then be analysed and the exact location of the source 5 can be determined.

[0106] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. The term “comprises” and its variations, such as “comprising” and “comprised of” is used throughout in an inclusive sense and not to the exclusion of any additional features.

[0107] It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect.

[0108] The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.

Claims

CLAIMS1. A data sampling apparatus connectable to a sensor, the data sampling apparatus comprising: a data sampling controller having a clock; an analog-to-digital converter (ADC), the ADC being connected to the data sampling controller and configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals; a global positioning system receiver connected to the data sampling controller and configured to generate Pulse-Per-Second (PPS) pulses and time data; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals; receive the digital data signals from the ADC and record a first clock cycle number of the clock of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected; receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the clock of the data sampling controller upon receipt of the PPS pulse; and generate a data packet including time data from the GPS receiver, first and second clock cycle numbers and the digital data signals.

2. The data sampling apparatus according to claim 1, wherein the data sampling controller is further configured to store the data packet.

3. The data sampling apparatus according to claim 1 or claim 2, wherein the data sampling controller is further configured to determine a timestamp of each digital data signal of the data packet based on the PPS pulses, time data, and first and second clock cycle numbers.

4. The data sampling apparatus according to any one of claims 1 to 3, wherein the data sampling apparatus is connected to one or more sensors.

5. A pair of data sampling apparatus each connectable to a corresponding sensor, each data sampling apparatus comprising: a data sampling controller having a clock; an analog-to-digital converter (ADC), the ADC being connected to the data sampling controller and configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals; a global positioning system receiver connected to the data sampling controller and configured to generate Pulse-Per-Second (PPS) pulses and time data; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals; receive the digital data signals from the ADC and record a first clock cycle number of the clock of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected;receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the clock of the data sampling controller upon receipt of the PPS pulse; and generate a data packet including time data from the GPS receiver, first and second clock cycle numbers and the digital data signals; wherein each data packet is synchronised in time to provide a timestamp for each digital data signal.

6. A time-synchronised data sampling system for sampling data across a plurality of sensors, the time synchronised data sampling system comprising: a plurality of data sampling apparatus, each data sampling apparatus being connectable to a sensor, wherein each data sampling apparatus comprises: a data sampling controller having a clock; an analog-to-digital converter (ADC) connected to the data sampling controller and configured to continuously sample analog data signals travelling through a propagation medium from the sensor and convert the analog data signals into digital data signals; a global positioning system receiver connected to the data sampling controller and configured to generate Pulse-Per-Second (PPS) pulses and time data; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals;receive the digital data signals from the ADC and record a first clock cycle number of the clock of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected; receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the clock of the data sampling controller upon receipt of the PPS pulse; and generate a data packet including time data from the GPS receiver, first and second clock cycle numbers and the digital data signals; and a central controller in digital communication with each data sampling apparatus and configured to receive data packets from each data sampling apparatus and determine a timestamp for each digital signal in each data packet.

7. The time-synchronised data sampling system according to claim 6, wherein each data packet is synchronised in time.

8. The time-synchronised data sampling system according to claim 6 or claim 7, wherein the central controller is configured to determine characteristics of the analog data signals and / or characteristics of the propagation medium from the data packets.

9. The time-synchronised data sampling system according to any one of claims 6 to 8, wherein the central controller is configured to: calculate an electrical distance between two sensors; and / or calculate a length of a powerline, and correlate the length against schematics to determine a circuit configuration; and / orcalculate a change in the length of a powerline in response to changes in temperature; and / or calculate a nature of propagation of external signals (such as lightning strikes) in power lines within a predetermined radius; and / or determine a type of one or more electrical devices in a circuit based on a presence of external signals detected by sensors subsequent to traveling through the one or more electrical devices.

10. The time-synchronised data sampling system according to any one of claims 6 to9, wherein the central controller is part of one of the plurality of data sampling apparatus.

11. The time-synchronised data sampling system according to any one of claims 6 to10, wherein the ADC collects 112 analog data signals that are converted into 112 corresponding digital data signals, wherein each data packet includes the 112 digital data signals.

12. A time-synchronised data sampling system for sampling data across a plurality of sensors, the time synchronised data sampling system comprising: a plurality of data sampling apparatus, a global positioning system configured to generate Pulse-Per-Second (PPS) pulses and time data; wherein each data sampling apparatus is connectable to a sensor located in a propagation medium and comprises: a data sampling controller having a clock; and an analog-to-digital converter connected to the data sampling controller and configured to continuously sample analog data signals travelling througha propagation medium from the sensor and convert the analog data signals into digital data signals; the data sampling controller being configured to: control the ADC to collect a plurality of analog data signals from the sensor and convert the plurality of analog data signals to digital data signals; receive the digital data samples from the ADC and record a first clock cycle number of the clock of the data sampling controller based on a time a final analog data signal of the plurality of analog data signals was collected; receive the PPS pulses and time data from the GPS receiver and record a second clock cycle number of the clock of the data sampling controller upon receipt of the PPS pulse; and generate a data packet based on the PPS pulses, time data, first and second clock cycle numbers and digital data signals; and a central controller configured to receive the data packets from each data sampling apparatus and determine a timestamp for each digital signal in each data packet.

13. The time-synchronised data sampling system according to claim 12, wherein the central controller is configured to determine one or more signal correlations based on the digital data signals.

14. A method for time-synchronised data sampling from one or more sensors, the method comprising:acquiring a plurality of analog data signals travelling through a propagation medium from a sensor; converting the plurality of analog data signals into digital data signals; recording a first clock cycle number of a clock of a data sampling controller based on a time a final analog data sample of the plurality of analog data samples was collected; receiving pulse-per-second pulses and time data from a GPS receiver; recording a second clock cycle number of the clock of the data sampling controller upon receipt of the PPS pulse and the time data; and generating a data packet including the time data from the GPS receiver, first and second clock cycle numbers and the digital data samples.

15. The method according to claim 14, wherein the method further includes storing the data packet.

16. The method according to claim 14 or claim 15, wherein the method further comprises acquiring a plurality of analog data signals travelling through the propagation medium from a plurality of sensors.

17. The method according to any one of claims 14 to 16, wherein the method further comprises generating a plurality of data packets corresponding to the plurality of sensors.

18. The method according to any one of claims 14 to 17, wherein the method further comprises determining characteristics of the analog data signals and / or characteristics of the propagation medium from the data packets.

19. The data sampling apparatus according to any one of claims 1 to 4, wherein the data sampling apparatus further comprises a first memory for storing the data packets.

20. The data sampling apparatus according to any one of claims 1 to 4 or claim 19, wherein the first memory is either SRAM (static random access memory) or flash memory.

21. The data sampling apparatus according to any one of claims 1 to 4 or claims 19 to 20, wherein the data sampling apparatus further comprises a second memory configured to store data packets when the first memory is full.

22. The time-synchronised data sampling system according to claim 6, wherein the system further comprises a plurality of sensors.

23. The time-synchronised data sampling system according to claim 22, wherein the system further comprises a plurality of distributed sensors.

24. The time-synchronised data sampling system according to claim 22 or claim 23, wherein each sensor is independent of every other sensor or the plurality of sensors are un-networked.

25. The time-synchronised data sampling system according to any one of claims 22 to 24, wherein each sensor comprises a shunt resistor connected to a main powerline; a hall effect sensor connected to an electrical wire; or a strain gauge connected to a water pipe.

26. The method according to any one of claims 14 to 18, wherein the method further includes determining a timestamp of each digital data signal of the data packet based on the PPS pulses, time data, and first and second clock cycle numbers.

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