CN113484870B - Ranging method and device, terminal and non-volatile computer readable storage medium - Google Patents
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- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
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Abstract
The application discloses a ranging method, a ranging device, a terminal and a nonvolatile computer readable storage medium. The ranging method comprises the following steps: acquiring a time-of-flight histogram; determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram; determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units; and calculating the distance between the sensor and the object according to the flight time and the light speed. According to the ranging method, the ranging device, the terminal and the nonvolatile computer readable storage medium, the flight time can be determined according to the parameter values of the peak units and the parameter values of the plurality of neighborhood units, so that more accurate flight time can be obtained, and the ranging precision can be improved.
Description
Technical neighborhood
The present application relates to the field of ranging technologies, and in particular, to a ranging method, a ranging device, a terminal, and a non-volatile computer readable storage medium.
Background
The direct time-of-flight technique (DIRECTED TIME of flight, dToF) is a ranging technique that calculates the distance between an object and a sensor by measuring the time difference between the transmitted signal and the signal reflected back by the object. The moment at which the sensor receives the signal reflected back by the object is usually determined by means of a histogram. Because of the limitation of hardware circuit design, the time resolution of the histogram, that is, the minimum unit of unit time counted by each square column corresponding to the abscissa, limits the size of the minimum statistic time unit, and it is difficult to further accurately determine the moment when the sensor receives the signal reflected by the object, so that the resolution of the final measurement output distance is limited.
Disclosure of Invention
The embodiment of the application provides a ranging method, a ranging device, a terminal and a nonvolatile computer readable storage medium.
The ranging method of the embodiment of the application comprises the following steps: acquiring a time-of-flight histogram; determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram; determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units; and calculating the distance between the sensor and the object according to the flight time and the light speed.
The distance measuring device comprises an acquisition module, a retrieval module, a determination module and a calculation module. The acquisition module may be configured to acquire a time-of-flight histogram. The retrieval module may be configured to determine a peak cell and a plurality of neighbor cells from the time cells based on the time of flight histogram. The determining module may be configured to determine the time of flight based on the parameter values of the peak cell and the parameter values of the plurality of neighbor cells. The calculation module may be used to calculate the distance between the sensor and the object based on the time of flight and the speed of light.
The terminal of the embodiment of the application comprises one or more processors, a memory and one or more programs. Wherein the one or more programs are stored in the memory and executed by the one or more processors, the programs including instructions for performing the ranging method of embodiments of the present application. The ranging method comprises the following steps: acquiring a time-of-flight histogram; determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram; determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units; and calculating the distance between the sensor and the object according to the flight time and the light speed.
A non-transitory computer readable storage medium containing a computer program that, when executed by one or more processors, causes the processors to implement the ranging method of embodiments of the present application. The ranging method comprises the following steps: acquiring a time-of-flight histogram; determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram; determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units; and calculating the distance between the sensor and the object according to the flight time and the light speed.
According to the ranging method, the ranging device, the terminal and the nonvolatile computer readable storage medium, the flight time can be determined according to the parameter values of the peak units and the parameter values of the plurality of neighborhood units, so that more accurate flight time can be obtained, and the ranging precision can be improved.
Additional aspects and advantages of embodiments of the application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the application.
Drawings
The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 2 is a schematic diagram of a terminal according to some embodiments of the present application;
FIG. 3 is a schematic diagram of a ranging apparatus according to some embodiments of the present application;
FIG. 4 is a schematic representation of a time-of-flight histogram of certain embodiments of the present application;
FIG. 5 is a schematic representation of a time-of-flight histogram of certain embodiments of the present application;
FIG. 6 is a schematic representation of a time-of-flight histogram of certain embodiments of the present application;
FIG. 7 is a schematic representation of a time-of-flight histogram of certain embodiments of the present application;
FIG. 8 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 9 is a schematic representation of a time-of-flight histogram of certain embodiments of the present application;
FIG. 10 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 11 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 12 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 13 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 14 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 15 is a flow chart of a ranging method according to some embodiments of the present application;
FIG. 16 is a schematic diagram of a connection of a computer readable storage medium and a processor according to some embodiments of the application.
Detailed Description
Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the embodiments of the present application and are not to be construed as limiting the embodiments of the present application.
The embodiment of the application provides a ranging method. Referring to fig. 1, a ranging method according to an embodiment of the present application includes:
01: acquiring a time-of-flight histogram, the time-of-flight histogram characterizing the number of photons received by the sensor in each time cell;
02: determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram;
03: determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units; and
04: And calculating the distance between the sensor and the object according to the flight time and the light speed.
Referring to fig. 2, the embodiment of the present application further provides a terminal 100, and the ranging method of the embodiment of the present application can be applied to the terminal 100. Terminal 100 includes one or more processors 30, memory 20, and one or more programs. Wherein one or more programs are stored in the memory 20 and executed by the one or more processors 30, the programs including instructions for performing the ranging methods of embodiments of the present application. That is, when the processor 30 executes the program, the processor 30 may implement the methods in steps 01, 02, 03, and 04. That is, the processor 30 may be configured to: acquiring a time-of-flight histogram; determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram; determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units; and calculating the distance between the sensor and the object according to the flight time and the light speed.
In some embodiments, terminal 100 further includes a transmitting end 40 and a sensor 50. The emitting end 40 is used for emitting a light beam, which contains a plurality of photons. The sensor 50 is configured to receive photons reflected back from an object. Thus, the time of flight can be determined from the time of emission of the light beam and the time of receipt of photons reflected back from the object by the sensor 50.
Referring to fig. 2 and 3, the embodiment of the application further provides a ranging apparatus 10, and the ranging apparatus 10 can be applied to a terminal 100. The distance measuring device 10 comprises an acquisition module 11, a retrieval module 12, a determination module 13, and a calculation module 14. The acquisition module 11 may be used to implement the method in 01, the retrieval module 12 may be used to implement the method in 02, the determination module 13 may be used to implement the method in 03, and the calculation module 14 may be used to implement the method in 04. That is, the acquisition module 11 may be used to acquire a time-of-flight histogram. Retrieval module 12 may be configured to determine a peak cell and a plurality of neighbor cells from the time cells based on the time-of-flight histogram. The determining module 13 may be configured to determine the time of flight according to the parameter values of the peak unit and the parameter values of the plurality of neighbor units. The calculation module 14 may be used to calculate the distance between the sensor 50 and the object based on the time of flight and the speed of light.
Please refer to fig. 1 to 3. Wherein the time of flight is the time taken for photons to exit from, reflect off of, and be received by the sensor 50, and the distance between the sensor 50 and the object can be calculated from the time of flight by time ranging, i.eWhere d is the distance between the sensor 50 and the object, c is the speed of light, and t is the time of flight. Based on the principle of time-of-flight ranging, the distance between the photon emitting end 40 and the sensor 50 is as close as possible to ensure the round trip distance of the photons, that is, the distance from the photon emitting end 40 to the object and the distance from the photon reflected back to the sensor 50 are as close as possible, thereby ensuring accurate ranging results.
Referring to fig. 4 and 5, the time-of-flight histogram characterizes the number of photons received by sensor 50 in each time cell. Specifically, the time-of-flight histogram characterizes the number of photons received by sensor 50 (shown in FIG. 2) in each time cell after m statistics. For example, counting the number of photons once every predetermined measurement period passes, and in one count, if the sensor 50 receives a photon, increasing the photon count value of the time unit in which the moment (determinable by the timestamp) at which the sensor 50 receives the photon is 1; if no photons are received by sensor 50 during a statistic, the photon count value is not incremented. In this manner, the number of photons received by sensor 50 in each time cell can be characterized based on the photon count value corresponding to each time cell.
In the time-of-flight histogram, the starting point of the time axis is the starting point of one measurement period and is also the time of emission of the photon. According to the time-of-flight ranging principle, the time-of-flight may be determined from the time at which the photon is emitted and the time at which the photon is received by the sensor 50. However, the photons received by the sensor 50 are not necessarily photons reflected back from the object, but may also be noise signals, such as photons present in the environment (ambient light). Thus, counting the number of photons only once does not determine whether the photons received by sensor 50 are photons reflected back from an object. In the time-of-flight histogram, by counting the number of photons received by the sensor 50 for a plurality of measurement periods, the number of photons received by the sensor 50 in each time unit can be obtained, and the photon count value corresponding to each time unit can reflect the energy value, i.e. the light intensity, of the photons received by the time unit. Referring to fig. 2, the light beam emitted by the emitting end 40 has a higher energy (light intensity), and the energy of the light beam is much higher than that of the noise signal. Thus, the light beam reflected from the object also has a higher energy (light intensity), and in the time-of-flight histogram, the larger the photon count value corresponding to the time cell, the higher the light intensity corresponding to the time cell, and the higher the probability that the photon counted by the time cell is a photon in the light beam reflected from the object.
Referring to fig. 4 and 5, specifically, in one embodiment, the time-of-flight histogram illustrated in fig. 4 is a time-of-flight histogram obtained through 10 statistics, and the time-of-flight histogram illustrated in fig. 5 is a time-of-flight histogram obtained through 100 statistics. The abscissa of the time-of-flight histogram represents time and the ordinate represents the number of photons received by the sensor 50. The time cells are time scales on an abscissa time axis, each time cell characterizing a period of time on the time axis. For example, the time-of-flight histogram includes 5 time units, and the two endpoints of the 1 st time unit on the time axis are 0ns and 0.5ns, respectively, and then the 1 st time unit characterizes a period of time between 0ns and 0.5ns on the time axis. The two endpoints of the 2 nd time unit on the time axis are 0.5ns and 1.0ns, respectively, and then the 2 nd time unit characterizes a period of time between 0.5ns and 1.0ns on the time axis. And so on, other time units are not listed here. In the time-of-flight histogram, each time cell is a statistical cell, and the height of each time cell, i.e., the ordinate corresponding to that time cell, characterizes the number of photons received by sensor 50 in that time cell after m statistics. For example, as shown in fig. 4, after 10 statistics, the ordinate corresponding to the 3 rd time unit is 5, which indicates that the sensor 50 receives 5 photons within the time period between 1.0ns and 1.5ns after 10 statistics, and the photon count value corresponding to the 3 rd time unit is 5. For example, as shown in fig. 5, after 100 statistics, the ordinate corresponding to the 5 th time unit is 52, which indicates that 52 photons are received by the sensor 50 in the time period between 1.0ns and 1.5ns after 100 statistics, and the photon count value corresponding to the 3 rd time unit is 52.
As described above in connection with the greater the photon count value for a time cell, the greater the intensity of the light for that time cell, and the greater the probability that the sensor 50 will receive photons reflected back from the object for that time cell, the greater the probability that the calculated distance based on the time of flight determined for that time cell will be the actual measured distance. Thus, to obtain an accurate time of flight, a peak unit needs to be determined from a plurality of time units to determine the time of flight based on the peak unit. The peak unit is the time unit with the largest photon count value, i.e. the time unit with the highest energy (light intensity).
However, the peak cell characterizes a period of time during which the sensor 50 receives photons reflected back from the object, and it cannot be determined which time within this period of time is the time at which the sensor 50 receives photons reflected back from the object. In some embodiments, the median time of the period characterized by the peak cell may be determined as the time at which the sensor 50 receives photons reflected back from the object. For example, in the histogram illustrated in fig. 5, where the peak unit is the 3 rd time unit, representing a period of time between 1.0ns and 1.5ns on the time axis, the time of 1.25ns is determined as the time at which the sensor 50 receives photons reflected back from the object to calculate the time of flight. Based on the above principle, when determining the moment when the sensor 50 receives a photon according to the peak unit, the smaller the range of the period of time represented by the peak unit, that is, the finer the square column corresponding to the peak unit (the narrower the width of the transverse axis), the more accurate the moment when the sensor 50 receives a photon reflected back from an object according to the peak unit. Theoretically, in a limit case, when a peak unit characterizes a moment, that moment is the moment when the sensor 50 receives photons reflected back from the object. Due to the limitations of the hardware circuit design, the time period characterized by the time cell, i.e. the time resolution of the time cell, has a minimum value, resulting in that the accuracy of the moment at which the sensor 50, which can be determined from the peak cell, receives photons reflected back from the object is limited by the minimum time resolution of the time cell. When the time resolution of a time unit reaches a minimum, the accuracy of the time determined from the time unit reaches a maximum, and cannot be further improved. Furthermore, if the time resolution of the time unit is too small, photon count statistics required to ensure ranging accuracy may be greatly increased, possibly resulting in reduced ranging efficiency.
The ranging method of the embodiment of the application can determine the peak value unit and a plurality of neighborhood units from the time unit according to the time-of-flight histogram, and determine the time-of-flight according to the parameter values of the peak value unit and the parameter values of the plurality of neighborhood units. Wherein the neighborhood of cells is at least one time cell adjacent to the peak cell, and the parameter values may include a resolution of the time cell, a photon count value corresponding to the time cell, a sequence number of time cells occurring in time order, and the like. For example, referring to fig. 5, if the peak unit is the 3 rd time unit, the 2 nd time unit and the 4 th time unit can be used as the neighbor units corresponding to the peak unit. The peak unit is the time unit with the highest energy (light intensity), and the neighborhood unit corresponding to the peak unit is often the time unit with higher energy (light intensity). Based on determining that the time at which the sensor 50 receives photons reflected back from the object is within the peak cell, it is further possible to determine, in combination with the parameter values of the neighborhood cells, whether the time at which the sensor 50 receives photons reflected back from the object is closer to the left neighborhood cell or closer to the right neighborhood cell.
For example, referring to fig. 6 and 7, in the time-of-flight histograms shown in fig. 6 and 7, the 41 st time cell is a peak cell, the neighborhood cell corresponding to the peak cell includes the 40 th time cell on the left side of the 41 st time cell and the 42 th time cell on the right side of the 41 st time cell, and t0 is a time corresponding to a midpoint of the peak cell along the horizontal axis direction. Let the time resolution of the time cell be 0.5ns, combined with the speed of light, the photons can move 0.075m in 0.5ns, corresponding to a distance resolution of 0.075m when the time resolution is 0.5 ns. From this, it can be calculated that the distance corresponding to the left end point of the peak unit is 3.000m and the distance corresponding to the right end point of the peak unit is 3.075m. Since the peak units characterize a period of time on the time axis, the time of flight is typically determined by taking the midpoint of the period of time, i.e., the median instant of the peak units. And a ranging result d1= 3.0375m calculated according to the time of flight t1 determined by the median time of the peak unit. If the time of flight t1 is determined based on the peak unit alone, then when the range of the true distance is [3.000m,3.075m ], no matter the true distance is any value within the range of [3.000m,3.075m ], the distance measurement result d1 calculated from the time of flight t1 and the light velocity is 3.0375m, and it is difficult to further calculate a more accurate distance in the case where the time resolution of the time unit cannot be reduced.
According to the ranging method provided by the embodiment of the application, the flight time can be determined according to the parameter values of the peak value unit and the parameter values of the plurality of neighborhood units, so that more accurate flight time can be determined, and the ranging precision is improved.
Specifically, referring to fig. 6, in the time-of-flight histogram shown in fig. 6, the photon count value corresponding to the 40 th time unit is greater than the photon count value corresponding to the 42 th time unit, and then the actual time-of-flight is at the left side of the median time of the peak unit, after the time-of-flight t2 is determined according to the parameter values of the peak unit and the parameter values of a plurality of neighbor units, the distance d2 calculated according to the time-of-flight t2 and the light velocity is within the range [3.0000m,3.0375m ], that is, when the actual distance is within the range [3.0000m,3.0375 m), the output d2 is taken as the ranging result. Namely, the distance resolution corresponding to the ranging result d2 is 0.0375m at the maximum, which is smaller than the distance resolution corresponding to the ranging result d1 by 0.075m; the corresponding time resolution is 0.25ns at maximum, which is less than the time resolution of the peak unit by 0.5ns.
Similarly, referring to fig. 7, in the time-of-flight histogram shown in fig. 7, the photon count value corresponding to the 40 th time unit is smaller than the photon count value corresponding to the 42 th time unit, so that the highest peak probability of the peak unit is at the right side of the midpoint of the peak unit along the horizontal axis direction, after the time-of-flight t3 is determined according to the parameter value of the peak unit and the parameter values of a plurality of neighbor units, the distance d3 calculated according to the time-of-flight t3 and the light velocity is within the range (3.0375 m,3.0750 m), that is, when the real distance is within the range (3.0375 m,3.075 m), the distance resolution corresponding to the distance measurement result d3 is 0.0375m at the maximum, and is smaller than the distance resolution corresponding to the distance measurement result d1 by 0.075m, and the corresponding time resolution is 0.25ns at the maximum, and is smaller than the time resolution of the peak unit by 0.5ns.
According to the above, the distance resolution corresponding to the ranging result d2 and the ranging result d3 is smaller than the distance resolution corresponding to the ranging result d1, that is, the ranging result d2 and the ranging result d3 have higher ranging accuracy compared with the ranging result d 1. Thereby improving the ranging accuracy without a decrease in the actual time resolution of the time unit. The above examples are only for illustrating the effect of improving the ranging accuracy of the ranging method according to the embodiment of the present application, and the degree of improvement of the ranging accuracy by the ranging method according to the embodiment of the present application is not limited to the degree of improvement illustrated in the above examples. That is, in the above-described embodiment, in the time-of-flight histograms shown in fig. 6 and 7, the ranging accuracy of the ranging result d2 and the ranging result d3 is improved by at least 2 times as compared to the ranging result d 1. The range finding method of the embodiment of the present application is not limited to 2 times, but may be 3 times, 4 times, or more in terms of the improvement degree of the range finding accuracy.
Further description is provided below with reference to the accompanying drawings.
Referring to fig. 8, in some embodiments, 01: acquiring a time-of-flight histogram, comprising:
011: acquiring a preset time period and a preset time resolution;
012: determining a plurality of time units according to the time period and the time resolution, wherein the time units are sequentially arranged on a time axis;
013: acquiring the arrival time of each photon at the sensor 50;
014: determining a time unit corresponding to each photon according to the arrival time; and
015: The number of photons corresponding to each time cell is counted to create a time-of-flight histogram.
Referring to fig. 2, in some embodiments, processor 30 may also be configured to implement the methods 011, 012, 013, 014, and 015. That is, the processor 30 may also be configured to: acquiring a preset time period and a preset time resolution; determining a plurality of time units according to the time period and the time resolution, wherein the time units are sequentially arranged on a time axis; acquiring the arrival time of each photon at the sensor 50; determining a time unit corresponding to each photon according to the arrival time; and counting the number of photons corresponding to each time cell to create a time-of-flight histogram.
Referring to fig. 3, in some embodiments, the acquisition module 11 may also be configured to implement the methods 011, 012, 013, 014, and 015. That is, the acquisition module 11 may also be configured to: acquiring a preset time period and a preset time resolution; determining a plurality of time units according to the time period and the time resolution, wherein the time units are sequentially arranged on a time axis; acquiring the arrival time of each photon at the sensor 50; determining a time unit corresponding to each photon according to the arrival time; and counting the number of photons corresponding to each time cell to create a time-of-flight histogram.
The longer the preset time period is, the larger the maximum value of the flight time which can be determined according to the flight time histogram is, and the larger the ranging range is; the shorter the preset period of time, the higher the ranging efficiency. When the preset time period is the same, the larger the preset time resolution (the wider the width of unit time), the peak value of the photon count value can obviously appear in the time-of-flight histogram by only carrying out photon quantity statistics for a small number of times, so that the ranging efficiency is improved; the smaller the preset time resolution (the narrower the width per unit time), the more accurate the time of flight that can be determined from the time of flight histogram, and the more accurate the ranging result.
In some embodiments, when the sensor 50 receives a photon, the sensor 50 generates a response signal. The processor 30 records a response time stamp as the arrival time of this photon when it receives the response signal. When the arrival time of a photon is acquired, a time unit corresponding to the arrival time can be found in the time-of-flight histogram, and the photon count value corresponding to the time unit is increased by 1. For example, referring to fig. 4, let a certain arrival time be 0.2ns, the photon count value corresponding to the 1 st time unit is increased by 1 according to the 0.2ns being in the time period from 0ns to 0.5ns, i.e. the 1 st time unit. After multiple photon counting statistics, counting the number of corresponding photons in each time unit, namely counting the photon counting value corresponding to each time unit, taking the photon counting value as the height of a square column of each time unit, and establishing a final time-of-flight histogram.
Referring to fig. 5, in some embodiments, the resolution of each time cell in the time-of-flight histogram is the same. In this way, the difficulty in accumulating photon count values for each time unit is the same, and it is possible to measure an arbitrary distance within the range with the same ranging accuracy.
Referring to fig. 9, in some embodiments, the time-of-flight histogram includes a region of interest and a non-region of interest, the resolution of the time cells of the region of interest being less than the resolution of the time cells of the non-region of interest. The region of interest is a time interval determined according to a distance of interest (the measured subject is within the distance range of interest), and the non-region of interest is a time interval outside the region of interest in the time-of-flight histogram, that is, a time interval determined according to a non-distance of interest (the measured subject is outside the distance range of non-interest). The smaller the resolution of a time cell, the more accurate the time of flight determined from that time cell, enabling ranging at a distance of interest with higher detection accuracy. For example, in the time-of-flight histogram illustrated in fig. 9, the time interval from 1ns to 2ns is the region of interest, and the 2 nd and 3 rd time units are the time units of the region of interest, with a corresponding time resolution of 0.5ns. The time interval other than the time interval of 1ns to 2ns is a non-interest region, and the time resolution corresponding to the time unit of the non-interest region is 1ns. The time units in the region of interest have a smaller resolution than the non-region of interest, and are divided more in the same time interval, and the time of flight determined from the time units of the region of interest is more accurate. And the time resolution corresponding to the time units of the non-interested area is set to be larger, so that the ranging efficiency can be improved.
Referring to fig. 10, in some embodiments, 02: determining a peak unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram, comprising:
021: acquiring a photon count value corresponding to each time unit;
022: determining a time unit corresponding to the maximum photon count value as a peak value unit; and
023: At least one time cell in the time-of-flight histogram that is adjacent to the left of the peak cell and at least one time cell that is adjacent to the right of the peak cell are determined as neighborhood cells.
Referring to FIG. 2, in some embodiments, processor 30 may also be configured to implement the methods 021, 022 and 023. That is, the processor 30 may also be configured to: acquiring a photon count value corresponding to each time unit; determining a time unit corresponding to the maximum photon count value as a peak value unit; and determining at least one time cell adjacent to the left of the peak cell and at least one time cell adjacent to the right of the peak cell in the time-of-flight histogram as a neighborhood cell.
Referring to FIG. 3, in some embodiments, the retrieval module 12 may also be used to implement the methods in 021, 022, and 023. That is, the retrieval module 12 may also be configured to: acquiring a photon count value corresponding to each time unit; determining a time unit corresponding to the maximum photon count value as a peak value unit; and determining at least one time cell adjacent to the left of the peak cell and at least one time cell adjacent to the right of the peak cell in the time-of-flight histogram as a neighborhood cell.
Referring to fig. 5, the ordinate of the square column of each time unit is the photon count value corresponding to the time unit. The ordinate of the highest square column along the vertical axis direction is the maximum photon count value, and the corresponding time unit of the square column is the peak value unit. The neighborhood cells are time cells adjacent to the peak cell and include at least one left neighborhood cell located to the left of the peak cell and at least one right neighborhood cell located to the right of the peak cell. The number of left neighbor cells may be 1,2, 3 or more, not specifically recited herein. When the number of the left neighborhood units is 1, the left neighborhood units are the nearest time units on the left side of the peak value unit; when the number of the left neighborhood units is n (n > 1), the left neighborhood units are n time units distributed in sequence along the left side of the horizontal axis from the nearest time unit on the left side of the peak unit. The number of right neighborhood elements may be 1,2, 3, or more, not specifically recited herein. In one embodiment, the neighborhood of cells includes 1 left neighborhood of cells and 1 right neighborhood of cells, such as in the time-of-flight histogram illustrated in FIG. 5, the 3 rd time cell is the peak cell and the 2 nd and 4 th time cells are the neighborhood of cells. At this time, the number of time units included in the neighborhood units is minimum, and the data processing amount is less when the flight time is determined according to the parameter values of the peak units and the parameter values of the neighborhood units, so that the ranging efficiency is higher.
Referring to fig. 11, in some embodiments, the parameter values include a resolution of time units, photon count values corresponding to the time units, and sequence numbers of time units occurring in time order. 03: determining the flight time according to the parameter values of the peak value unit and the parameter values of the plurality of neighborhood units comprises:
031: acquiring a peak value count value corresponding to a peak value unit, a left count value corresponding to a left neighborhood unit and a right count value corresponding to a right neighborhood unit;
032: determining a correction value according to the peak value count value, the left count value, the right count value and a preset correction parameter; and
033: And determining the flight time according to the resolution of the peak value unit, the serial number of the peak value unit and the correction value.
Referring to fig. 2, in some embodiments, the processor 30 may also be configured to implement the methods of 031, 032, and 033. That is, the processor 30 may also be configured to: acquiring a peak value count value corresponding to a peak value unit, a left count value corresponding to a left neighborhood unit and a right count value corresponding to a right neighborhood unit; determining a correction value according to the peak value count value, the left count value, the right count value and a preset correction parameter; and determining the flight time according to the resolution of the peak unit, the serial number of the peak unit and the correction value.
Referring to fig. 3, in some embodiments, the determining module 13 may also be configured to implement the methods of 031, 032, and 033. That is, the determination module 13 may also be configured to: acquiring a peak value count value corresponding to a peak value unit, a left count value corresponding to a left neighborhood unit and a right count value corresponding to a right neighborhood unit; determining a correction value according to the peak value count value, the left count value, the right count value and a preset correction parameter; and determining the flight time according to the resolution of the peak unit, the serial number of the peak unit and the correction value.
Referring to fig. 6 and 7, as described above, the time of flight can be determined based on the time t Emission of of the emitted photon and the time t Reception of of the reflected photon from the object received by the sensor 50, i.e., time of flight t=t Reception of -t Emission of . In some embodiments, the median time of day t0 of the peak unit is taken as t Reception of to determine the time of flight t1 based on the peak unit. Since the median time t0 of the peak unit depends on the time resolution corresponding to the peak unit, the smaller the time resolution corresponding to the peak unit is, the more accurate the median time t0 can be determined. Therefore, in the case where the resolution of the peak unit is limited and cannot be reduced, the peak unit has a fixed median time t0, and the accuracy of the time of flight t1 determined from the median time t0 is limited.
The ranging method of the embodiment of the application can determine the correction value according to the peak value count value, the left count value, the right count value and the preset correction parameter, so as to determine the flight time according to the resolution of the peak unit, the serial number of the peak unit and the correction value, thereby determining the flight time with higher accuracy. When the peak unit is the nth time unit on the horizontal axis of the time of flight histogram, the serial number of the peak unit is n. The correction parameter is a preset constant value and represents the influence of the peak value count value, the left count value and the right count value on the correction value. The correction value can characterize the offset of the time t Reception of at which the sensor 50 receives a photon reflected back from the object relative to the peak cell. The correction value may take a positive value, a negative value, or 0. When the correction value is positive, the time t Reception of , which characterizes the sensor 50 receiving photons reflected back from the object, is to the right of the median time t0 of the peak unit, i.e. t Reception of > t0; when the correction value is negative, the characterization time t Reception of is to the left of time t0, i.e., t Reception of < t0; when the correction value is 0, the characterization may take the median time t0 of the peak unit as t Reception of , i.e. t Reception of =t0.
For example, the number of peak cells is 41 and the correction value is-0.45, then the corrected number is 40.55, and it can be determined that the time t Reception of at which the photon reflected from the object was received by the sensor 50 is to the left of the median time t0 of the peak cells. In the time-of-flight histogram, all time units have a positive integer number n, and no time unit with a number of 40.55 actually exists in the time-of-flight histogram, but the time t Reception of is determined based on the time unit with a number of 40.55 to determine the time of flight. In one embodiment, the time resolution of each time cell is the same, and the median time tn ' of the time cell with the sequence number 40.55 can be determined in combination with the time resolution, for example, the time resolution is 0.5ns, then tn ' =0.5 ns×40.55- (0.5 ns/2) = 20.025ns, and tn ' is taken as the time t Reception of when the sensor 50 receives the photon reflected back from the object to determine the time of flight.
Referring to fig. 12, in some embodiments, the correction parameters include a first parameter, a second parameter, and a third parameter. 032: determining a correction value according to the peak value count value, the left count value, the right count value and a preset correction parameter, wherein the method comprises the following steps:
0321: acquiring a weighted peak value count value according to the peak value count value and the first parameter;
0322: acquiring a weighted right count value according to the right count value and the second parameter;
0323: acquiring a weighted left count value according to the left count value and the third parameter;
0324: acquiring a first difference value between a right count value and a left count value;
0325: obtaining a second difference value obtained by sequentially differencing the weighted peak value count value and the weighted right count value and the weighted left count value; and
0326: And acquiring the ratio of the first difference value to the second difference value, and determining the ratio as a correction value.
Referring to fig. 2, in some embodiments, the processor 30 may also be configured to implement the methods of 0321, 0322, 0323, 0324, 0325, and 0326. That is, the processor 30 may also be configured to: acquiring a weighted peak value count value according to the peak value count value and the first parameter; acquiring a weighted right count value according to the right count value and the second parameter; acquiring a weighted left count value according to the left count value and the third parameter; acquiring a first difference value between a right count value and a left count value; obtaining a second difference value obtained by sequentially differencing the weighted peak value count value and the weighted right count value and the weighted left count value; and obtaining the ratio of the first difference value to the second difference value, and determining the ratio as a correction value.
Referring to fig. 3, in some embodiments, the determining module 13 may be further configured to implement the methods of 0321, 0322, 0323, 0324, 0325, and 0326. That is, the determination module 13 may also be configured to: acquiring a weighted peak value count value according to the peak value count value and the first parameter; acquiring a weighted right count value according to the right count value and the second parameter; acquiring a weighted left count value according to the left count value and the third parameter; acquiring a first difference value between a right count value and a left count value; obtaining a second difference value obtained by sequentially differencing the weighted peak value count value and the weighted right count value and the weighted left count value; and obtaining the ratio of the first difference value to the second difference value, and determining the ratio as a correction value.
For example, the first parameter is a, the second parameter is b, the third parameter is c, the peak count value is P1, the right count value is P2, and the left count value is P3. From this, it can be calculated that: the weighted peak count value pq1=a×p1, the weighted right count value pq2=b×p2, the weighted left count value pq3=c×p3, the first difference f1=p2-P3, the second difference f2=pq1-pq2-pq3=a×p1-b×p2-c×p3. Setting the correction value as DeltanThe first parameter a, the second parameter b and the third parameter c are preset constants and can be obtained according to calibration before delivery.
Referring to fig. 13, in some embodiments, 033: determining the flight time according to the resolution of the peak unit, the serial number of the peak unit and the correction value comprises the following steps:
0331: and determining the correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and determining the flight time according to the correction sequence number and the resolution of the peak unit.
Referring to fig. 2, in some embodiments, the processor 30 may also be configured to implement the method of 0331. That is, the processor 30 may also be configured to: and determining the correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and determining the flight time according to the correction sequence number and the resolution of the peak unit.
Referring to fig. 3, in some embodiments, the determining module 13 may also be configured to implement the method of 0331. That is, the determination module 13 may also be configured to: and determining the correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and determining the flight time according to the correction sequence number and the resolution of the peak unit.
Specifically, if the number of the peak unit is n and the correction value is Δn, the number n' =n++Δn is corrected. The Δn may be a positive value, a negative value, or 0, as described above.
Referring to fig. 6, in one embodiment, the actual distance between the sensor 50 and the object is 3m, and the time-of-flight histogram obtained after multiple statistics is: the number n=41 of the peak unit, the correction value Δn= -0.45, the time resolution k=0.5 ns of the peak unit. From this, it can be calculated that: correction sequence n' =n+ +Δn=41+ (-0.45) =40.55. Let the time of flight be t, time of flight t=t Reception of -t Emission of , where t Emission of is the time at which the photon is emitted and t Reception of is the time at which the photon reflected back from the object is received by the sensor 50. In the time-of-flight histogram of the present embodiment, the photon count value is counted from the time when the photon is emitted, and therefore t Emission of =0 ns, and the time-of-flight t=t Reception of . And t Reception of can be determined according to the following equation: t Reception of = n' ×k- (K/2). Wherein n ' x K represents the moment of the corrected peak unit corresponding to the right endpoint coordinate of the time axis, K/2 is half of the time resolution, namely n ' x K- (K/2) represents the median moment of the n ' th time unit. Substituting n ' =40.55, k=0.5 ns for t Reception of =n ' ×k- (K/2), the time of flight t=t Reception of =n ' ×k- (K/2) =40.55×0.5ns- (0.5 ns/2) = 20.025ns can be calculated. Thus, in combination with 04: calculating the distance between the sensor 50 and the object from the time of flight and the speed of light, substituting t= 20.025 ns= 20.025 × -9s,c＝3×108 m/s intoThe distance d= (20.025 ×10 -9s×3×108 m/s)/2= 3.00375m can be calculated.
As a control, the flight time t1=n×k- (K/2) =41×0.5ns- (0.5 ns/2) =20.25 ns determined from the parameter values of the peak units alone. Distance d1= (20.25×10 -9s×3×108 m/s)/2= 3.0375m acquired from time of flight t 1. It can be seen that d calculated from the time of flight t is closer to the actual distance between the sensor 50 and the object than d1 calculated from the time of flight t1, so that a more accurate time of flight can be determined by determining the time of flight from the resolution of the peak unit, the serial number of the peak unit and the correction value.
Further, in the present embodiment (the embodiment illustrated in fig. 6), when the time resolution K of the peak unit has been determined to be 0.5ns, the distance resolution h=0.5 ns×3×10 8 m/s=0.075 m of the peak unit, if the time of flight t1 is determined based on only the parameter value of the peak unit, the actual distance between the sensor 50 and the object is any value in the range of [3.000m,3.075m ], the time of flight t1 determined based on the parameter value of the peak unit is 20.25ns, the measurement distance d1 determined based on the time of flight t is 3.0375m, and the maximum error is 0.0375m. The flight time t determined according to the resolution of the peak unit, the serial number of the peak unit and the correction value is related to the correction value deltan, and the correction value is related to the parameter value of the peak unit, the parameter value of the left neighborhood unit and the parameter value of the right neighborhood unit, so that the offset degree of the sensor 50 in the left neighborhood unit or the right neighborhood unit of the peak unit at the time t Reception of when the photon reflected by the object is received can be represented. In this embodiment, when Δn is less than 0, the range of the value of the flight time t is [20.00ns,20.25 ns), the range of the distance d which can be determined according to the value of the flight time t is [3.0000m,3.0375 m), and the maximum error is less than 0.0375m; when Deltan > 0, the range of the flight time t is (20.25 ns,20.50 ns), the range of the distance d which can be determined according to the value of the flight time t is (3.0375 m,3.0750 m), and the maximum error is smaller than 0.0375m, namely when Deltan is not 0, the accuracy of the flight time t is improved compared with the flight time t1, and the accuracy of the measurement distance d determined by the flight time t is improved compared with the measurement distance d1 determined by the flight time t 1.
Referring to fig. 14, in some embodiments, 033: determining the flight time according to the resolution of the peak unit, the serial number of the peak unit and the correction value comprises the following steps:
0332: and determining peak time according to the serial number and the resolution of the peak unit, determining correction time according to the correction value and the resolution, and determining flight time according to the peak time and the correction time.
Referring to fig. 2, in some embodiments, the processor 30 may also be configured to implement the method of 0332. That is, the processor 30 may also be configured to: and determining peak time according to the serial number and the resolution of the peak unit, determining correction time according to the correction value and the resolution, and determining flight time according to the peak time and the correction time.
Referring to fig. 3, in some embodiments, the determining module 13 may also be configured to implement the method in 0332. That is, the determination module 13 may also be configured to: and determining peak time according to the serial number and the resolution of the peak unit, determining correction time according to the correction value and the resolution, and determining flight time according to the peak time and the correction time.
Referring to fig. 6, the number of peak units is denoted by n, the time resolution of each time unit is denoted by K, and the correction value is denoted by Δn. When the median time t0 of the peak unit is taken as the peak time tn corresponding to the peak unit, the peak time tn=n×k- (K/2) can be calculated. In some embodiments, any time tr in the peak unit may be taken as the peak time tn corresponding to the peak unit, and then the peak time tn=n×k- (k×u) may be calculated, where u is a ratio of a time period from the time tr to a right endpoint time of the peak unit to the time resolution K, for example, when the time tr is a median time of the peak unit, u=1/2. Correction time Δt= Δn×k, flight time t=tn+ # t. In some embodiments, the correspondence between the sequence number of each time unit and the time instant to which that time unit corresponds has been determined at the time of flight histogram creation and stored in the memory 20. When a certain time unit is determined as a peak unit, the peak time tn can be determined according to the serial number of the peak unit and the corresponding relation, so that calculation is simplified, and the ranging efficiency is improved.
Referring to fig. 15, in some embodiments, 033: determining the flight time according to the resolution of the peak unit, the serial number of the peak unit and the correction value comprises the following steps:
0333: and determining the correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and taking the moment corresponding to the correction sequence number on the flight time histogram as the flight time.
Referring to fig. 2, in some embodiments, the processor 30 may also be configured to implement the method of 0333. That is, the processor 30 may also be configured to: and determining the correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and taking the moment corresponding to the correction sequence number on the flight time histogram as the flight time.
Referring to fig. 3, in some embodiments, the determining module 13 may also be configured to implement the method of 0333. That is, the determination module 13 may also be configured to: and determining the correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and taking the moment corresponding to the correction sequence number on the flight time histogram as the flight time.
Please refer to fig. 6, specifically, let the number of the peak unit be n and the correction be Δn. Then a correction sequence number n '=n+' Δn can be calculated. As described above, the photon count value is counted in the time-of-flight histogram from the moment of emission of the photon, so t Emission of =0 ns, time-of-flight t=t Reception of . In some embodiments, the peak time tn 'of the modified peak unit (i.e., time unit numbered n') is taken as t Reception of . In the time-of-flight histogram, the peak time tn ' of the time cell with n ' is represented as the time corresponding to the time cell with n ' on the time axis of the time-of-flight histogram. The correspondence between the sequence number of each time unit and the time of the time unit corresponding to the time axis has been determined at the time of flight histogram creation, and the correspondence is stored in the memory 20. After the serial number n 'of the corrected peak unit is determined, the peak time tn' and the flight time t=tn 'can be determined according to the serial number n' and the corresponding relation, so that the calculation is simplified, and the ranging efficiency is improved.
Referring to fig. 16, one or more non-transitory computer-readable storage media 300 embodying a computer program 301, which when executed by one or more processors 30, causes the processors 30 to perform the ranging method of any of the above embodiments, e.g., implementing one or more of steps 01, 02, 03, 04, 011, 012, 013, 014, 015, 021, 022, 023, 031, 032, 033, 0321, 0322, 0323, 0324, 0325, 0326, 0331, 0332, and 0333.
For example, when the computer program 301 is executed by one or more processors 30, the processor 30 is caused to perform the steps of:
01: acquiring a time-of-flight histogram, the time-of-flight histogram characterizing the number of photons received by the sensor in each time cell;
02: determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram;
03: determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units; and
04: And calculating the distance between the sensor and the object according to the flight time and the light speed.
As another example, the computer program 301, when executed by the one or more processors 30, causes the processors 30 to perform the steps of:
011: acquiring a preset time period and a preset time resolution;
012: determining a plurality of time units according to the time period and the time resolution, wherein the time units are sequentially arranged on a time axis;
013: acquiring the arrival time of each photon to the sensor;
014: determining a time unit corresponding to each photon according to the arrival time;
015: counting the number of photons corresponding to each time unit to establish a time-of-flight histogram;
021: acquiring a photon count value corresponding to each time unit;
022: determining a time unit corresponding to the maximum photon count value as a peak value unit;
023: determining at least one time cell adjacent to the left of the peak cell and at least one time cell adjacent to the right of the peak cell in the time-of-flight histogram as a neighborhood cell;
031: acquiring a peak value count value corresponding to a peak value unit, a left count value corresponding to a left neighborhood unit and a right count value corresponding to a right neighborhood unit;
032: determining a correction value according to the peak value count value, the left count value, the right count value and a preset correction parameter; and
033: Determining the flight time according to the resolution of the peak value unit, the serial number of the peak value unit and the correction value;
04: the distance between the sensor 50 and the object is calculated from the time of flight and the speed of light.
In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the various embodiments or examples described in this specification and the features of the various embodiments or examples may be combined and combined by those skilled in the art without contradiction.
Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and further implementations are included within the scope of the preferred embodiment of the present application in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present application.
While embodiments of the present application have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the application, and that variations, modifications, alternatives, and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the application.
Claims (8)
1. A ranging method, comprising:
Acquiring a time-of-flight histogram characterizing the number of photons received by the sensor in each time cell;
Determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram;
Determining flight time according to the parameter values of the peak value unit and the parameter values of a plurality of neighborhood units, wherein the neighborhood units comprise a left neighborhood unit positioned at the left side of the peak value unit and a right neighborhood unit positioned at the right side of the peak value unit, and the parameter values comprise the resolution of the time unit, photon count values corresponding to the time unit and sequence numbers of the time unit according to a time sequence; the determining the flight time according to the peak value unit and the neighborhood units comprises:
acquiring a peak value count value corresponding to the peak value unit, a left count value corresponding to the left neighborhood unit and a right count value corresponding to the right neighborhood unit;
Determining a correction value according to the peak value count value, the left count value, the right count value and a preset correction parameter; and
Determining the time of flight according to the resolution of the peak unit, the sequence number of the peak unit and the correction value, the determining the time of flight according to the resolution of the peak unit, the sequence number of the peak unit and the correction value comprising:
Determining a correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and determining the flight time according to the correction sequence number and the resolution of the peak unit; or (b)
Determining a peak time according to the serial number of the peak unit and the resolution, determining a correction time according to the correction value and the resolution, and determining the flight time according to the peak time and the correction time; or (b)
Determining a correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and taking the moment corresponding to the correction sequence number on the flight time histogram as the flight time; and
And calculating the distance between the sensor and the object according to the flight time and the light speed.
2. The ranging method as defined in claim 1 wherein the acquiring a time-of-flight histogram comprises:
acquiring a preset time period and a preset time resolution;
Determining a plurality of time units according to the time period and the time resolution, wherein the time units are sequentially arranged on a time axis;
acquiring the arrival time of each photon to the sensor;
determining a time unit corresponding to each photon according to the arrival time; and
And counting the number of photons corresponding to each time unit to establish the time-of-flight histogram.
3. The ranging method as claimed in claim 1, wherein,
The resolution of each of the time cells in the time-of-flight histogram is the same; or (b)
The time-of-flight histogram includes a region of interest and a non-region of interest, a resolution of time units of the region of interest being less than a resolution of time units of the non-region of interest.
4. The ranging method as defined in claim 1 wherein the determining a peak cell and a plurality of neighbor cells from the time cells according to the time-of-flight histogram comprises:
acquiring a photon count value corresponding to each time unit;
Determining a time unit corresponding to the maximum photon count value as the peak value unit; and
At least one time cell in the time-of-flight histogram that is adjacent to the left of the peak cell and at least one time cell that is adjacent to the right of the peak cell are determined as the neighborhood cell.
5. The ranging method as claimed in claim 1, wherein the correction parameters include a first parameter, a second parameter, and a third parameter, and the determining the correction value according to the peak count value, the left count value, the right count value, and a preset correction parameter comprises:
Acquiring a weighted peak value count according to the peak value count and the first parameter;
acquiring a weighted right count value according to the right count value and the second parameter;
acquiring a weighted left count value according to the left count value and the third parameter;
Acquiring a first difference value between the right count value and the left count value;
Acquiring a second difference value obtained by sequentially differencing the weighted peak value count value and the weighted right count value and the weighted left count value; and
And acquiring a ratio of the first difference value to the second difference value, and determining the ratio as the correction value.
6. A ranging apparatus, comprising:
The acquisition module is used for acquiring a time-of-flight histogram, and the time-of-flight histogram characterizes the number of photons received by the sensor in each time unit;
The searching module is used for determining a peak value unit and a plurality of neighborhood units from the time units according to the time-of-flight histogram;
The determining module is used for determining the flight time according to the parameter values of the peak units and the parameter values of a plurality of neighborhood units, and is also used for: acquiring a peak value count value corresponding to the peak value unit, a left count value corresponding to the left neighborhood unit and a right count value corresponding to the right neighborhood unit; determining a correction value according to the peak value count value, the left count value, the right count value and a preset correction parameter; and determining the time of flight according to the resolution of the peak unit, the sequence number of the peak unit, and the correction value, the determination module further configured to: determining a correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and determining the flight time according to the correction sequence number and the resolution of the peak unit; or, determining a peak time according to the serial number of the peak unit and the resolution, determining a correction time according to the correction value and the resolution, and determining the flight time according to the peak time and the correction time; or determining a correction sequence number of the peak unit according to the sequence number of the peak unit and the correction value, and taking the moment corresponding to the correction sequence number on the flight time histogram as the flight time; and
And the calculating module is used for calculating the distance between the sensor and the object according to the flight time and the light speed.
7. A terminal, the terminal comprising:
one or more processors, memory; and
One or more programs, wherein the one or more programs are stored in the memory and executed by the one or more processors, the programs comprising instructions for performing the ranging method of any of claims 1-5.
8. A non-transitory computer readable storage medium containing a computer program which, when executed by one or more processors, causes the processors to implement the ranging method of any of claims 1 to 5.
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| CN113484870B (en) * | 2021-07-20 | 2024-05-14 | Oppo广东移动通信有限公司 | Ranging method and device, terminal and non-volatile computer readable storage medium |
| CN114509740B (en) * | 2022-04-18 | 2022-08-09 | 深圳阜时科技有限公司 | Time-of-flight offset correction method, ToF device, electronic apparatus, and storage medium |
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