Time synchronization device, sensor system and electric equipment

Abstract

The utility model provides a time synchronization device, a sensor system and electric equipment, the time synchronization device comprises a satellite signal receiving unit, a crystal oscillator time output unit and a synchronization unit, the satellite signal receiving unit is used for receiving a satellite signal and at least outputting a satellite second pulse signal according to the satellite signal; the crystal oscillator time output unit is at least used for outputting a crystal oscillator second pulse signal and local crystal oscillator time; the synchronization unit is respectively connected with the satellite signal receiving unit and the crystal oscillator time output unit, and is used for correcting the crystal oscillator second pulse signal and the local crystal oscillator time according to the received satellite second pulse signal, so that the crystal oscillator time output unit outputs a crystal oscillator synchronization second pulse signal and the local synchronization crystal oscillator time, the crystal oscillator synchronization second pulse signal is the corrected crystal oscillator second pulse signal, and the local synchronization crystal oscillator time is the corrected local crystal oscillator time. According to the invention, the time synchronization requirement when the satellite signal is weak can be met.

Description

Technical Field

[0001] The present application relates to the technical field of heterogeneous synchronization, and in particular to a time synchronization device, a sensor system and an electrical device. Background Art

[0002] At present, with the development of technologies such as intelligent driving, the requirements for spatial synchronization and time synchronization between heterogeneous devices are becoming increasingly higher. In particular, heterogeneous devices need to be given more accurate time to meet the needs of intelligent development. However, current heterogeneous devices often rely on satellite signals. When the satellite signal is weak, the local area cannot provide the precise time required by the heterogeneous devices. Therefore, how to provide accurate time locally when the satellite signal is weak has become a problem that needs to be considered. Utility Model Content

[0003] The present application provides a time synchronization device, a sensor system and an electrical device, which can meet the time synchronization requirements when the satellite signal is weak.

[0004] In a first aspect, a time synchronization device is provided, comprising a satellite signal receiving unit, a crystal oscillator time output unit and a synchronization unit, wherein the satellite signal receiving unit is used to receive a satellite signal and output at least a satellite second pulse signal according to the satellite signal; the crystal oscillator time output unit is used to output at least a crystal oscillator second pulse signal and a local crystal oscillator time; the synchronization unit is connected to the satellite signal receiving unit and the crystal oscillator time output unit respectively, and is used to correct the crystal oscillator second pulse signal and the local crystal oscillator time according to the received satellite second pulse signal, so that the crystal oscillator time output unit outputs a crystal oscillator synchronized second pulse signal and a local synchronized crystal oscillator time, wherein the crystal oscillator synchronized second pulse signal is the corrected crystal oscillator second pulse signal, and the local synchronized crystal oscillator time is the corrected local crystal oscillator time.

[0005] In a possible implementation, the satellite signal receiving unit is also used to output timing data, and the crystal oscillator time output unit is also used to output the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time; the time synchronization device also includes a parsing unit and a selection unit, the parsing unit is connected to the satellite signal receiving unit, and the selection unit is respectively connected to the satellite signal receiving unit, the parsing unit and the crystal oscillator time output unit; wherein the parsing unit is used to receive the timing data, and parse the timing data to obtain the world standard time, the selection unit is used to receive the satellite second pulse signal, the world standard time, the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time, and can selectively output the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time, or output the satellite second pulse signal and the world standard time.

[0006] In a possible implementation, the crystal oscillator time output unit includes a crystal oscillator module and a frequency division module, the crystal oscillator module is connected to the frequency division module, and the frequency division module is respectively connected to the synchronization unit and the selection unit; wherein, the crystal oscillator module is used to output an initial crystal oscillator pulse signal, and the frequency division module is at least used to receive the initial crystal oscillator pulse signal, divide the initial crystal oscillator pulse signal according to a frequency division coefficient to obtain the crystal oscillator second pulse signal, and output the crystal oscillator second pulse signal.

[0007] In a possible implementation, the synchronization unit includes a comparison module and a frequency division coefficient adjustment module, the comparison module is connected to the satellite signal receiving unit and the frequency division module respectively, the comparison module is used to compare the phase of the satellite second pulse signal with the phase of the crystal oscillator second pulse signal to obtain a corresponding comparison result signal, and the frequency division coefficient adjustment module is used to adjust the frequency division coefficient of the frequency division module according to the comparison result signal to correct the crystal oscillator second pulse signal and the local crystal oscillator time.

[0008] In a possible embodiment, the frequency division module includes a frequency divider and a counter, the frequency divider is connected to the crystal oscillator module, and the counter is respectively connected to the frequency divider and the selection unit; wherein the frequency divider is at least used to divide the initial crystal oscillator pulse signal according to the adjusted frequency division coefficient to obtain a corrected intermediate crystal oscillator pulse signal, the counter is at least used to adjust the pulse width of the corrected intermediate crystal oscillator pulse signal to generate the crystal oscillator synchronized second pulse signal, and count the crystal oscillator synchronized second pulse signal to generate the local synchronized crystal oscillator time, and the frequency division module is also used to output the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time to the selection unit.

[0009] In a possible implementation, the comparison result signal includes a phase difference between the satellite second pulse signal and the crystal oscillator second pulse signal, and the frequency division coefficient adjustment module is used to adjust the frequency division coefficient of the frequency division module according to the phase difference between the satellite second pulse signal and the crystal oscillator second pulse signal.

[0010] In a possible embodiment, the synchronization unit also includes a phase pulse generating module, which is connected between the satellite signal receiving unit and the comparison module, and is used to generate a phase pulse signal according to the rising edge of the received satellite second pulse signal, and output the phase pulse signal, and the phase of the phase pulse signal is the same as the phase of the satellite second pulse signal; the comparison module is used to receive the phase pulse signal and the crystal oscillator second pulse signal output by the frequency division module, and compare the phase of the satellite second pulse signal with the phase of the crystal oscillator second pulse signal by comparing the phase of the phase pulse signal with the phase of the crystal oscillator second pulse signal, and obtain a corresponding comparison result signal.

[0011] In a possible implementation, the selection unit is used to determine the number of satellites sending the satellite signal based on the received satellite signal, and when the number of satellites whose satellite signals are received by the satellite signal receiving unit is less than 3, the selection unit outputs the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time; when the number of satellites whose satellite signals are received by the satellite signal receiving unit is greater than or equal to 3, the selection unit outputs the satellite second pulse signal and the world standard time.

[0012] In a second aspect, a sensor system is also provided, the sensor system comprising the above-mentioned time synchronization device and a sensor unit, the time synchronization device being at least used for correcting the crystal oscillator second pulse signal and the local crystal oscillator time provided by the crystal oscillator time output unit when the crystal oscillator time output unit provides the sensor unit with the crystal oscillator second pulse signal and the local crystal oscillator time. The time synchronization device comprises a satellite signal receiving unit, a crystal oscillator time output unit and a synchronization unit, the satellite signal receiving unit being used for receiving a satellite signal and outputting at least a satellite second pulse signal according to the satellite signal; the crystal oscillator time output unit being used for outputting at least a crystal oscillator second pulse signal and the local crystal oscillator time; the synchronization unit being connected to the satellite signal receiving unit and the crystal oscillator time output unit respectively, and being used for correcting the crystal oscillator second pulse signal and the local crystal oscillator time according to the received satellite second pulse signal, so that the crystal oscillator time output unit outputs a crystal oscillator synchronization second pulse signal and a local synchronization crystal oscillator time, wherein the crystal oscillator synchronization second pulse signal is the corrected crystal oscillator second pulse signal, and the local synchronization crystal oscillator time is the corrected local crystal oscillator time.

[0013] In a third aspect, an electrical device is also provided, the electrical device comprising the above-mentioned sensor system. The sensor system comprises the above-mentioned time synchronization device and a sensor unit, the time synchronization device being at least used for correcting the crystal oscillator second pulse signal and the local crystal oscillator time provided by the crystal oscillator time output unit when the crystal oscillator time output unit provides the crystal oscillator second pulse signal and the local crystal oscillator time to the sensor unit.

[0014] The time synchronization device, sensor system and electrical equipment of the present application can correct the crystal oscillator second pulse signal and the local crystal oscillator time by configuring a synchronization unit and using the satellite second pulse signal output by the satellite signal receiving unit, so that the crystal oscillator time output unit outputs a crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time. When the satellite signal is weak, accurate time is provided locally to meet the time synchronization requirements when the satellite signal is weak. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0016] Figure 1 FIG. 1 is a schematic diagram of a time synchronization device in an embodiment of the present application.

[0017] Figure 2 FIG. 1 is a schematic diagram of a time synchronization device in another embodiment of the present application.

[0018] Figure 3 FIG. 4 is a schematic diagram of a time synchronization device in another embodiment of the present application.

[0019] Figure 4 Schematic diagram of a crystal oscillator time output unit in an embodiment of the present application.

[0020] Figure 5 is a schematic diagram of a synchronization unit in an embodiment of the present application.

[0021] Figure 6 is a schematic diagram of a frequency division module in an embodiment of the present application.

[0022] Figure 7 This is a waveform diagram showing the phase comparison of the satellite second pulse signal, the phase pulse signal and the crystal second pulse signal in one embodiment of the present application.

[0023] Figure 8 FIG. 4 is a schematic diagram of a satellite signal receiving unit in an embodiment of the present application.

[0024] Fig. 9 is a schematic diagram of a sensor system in an embodiment of the present application.

[0025] Fig.10 is a schematic diagram of a sensor system in another embodiment of the present application.

[0026] Fig.11 1 is a step diagram of a synchronization method for a sensor system in an embodiment of the present application.

[0027] Fig.12 This is a step diagram of a synchronization method for a sensor system in another embodiment of the present application.

[0028] Fig.13 This is a step diagram of a synchronization method for a sensor system in yet another embodiment of the present application.

[0029] Fig.14 It is a schematic diagram of an electrical device in an embodiment of the present application.

[0030] Explanation of the accompanying drawings: 10. Time synchronization device, 100. Satellite signal receiving unit, 110. Satellite antenna, 120. Satellite receiver, 1PPS, satellite second pulse signal, 200. Synchronization unit, 210. Comparison module, 220. Frequency division coefficient adjustment module, 230. Phase pulse generation module, Ps, phase pulse signal, 300. Crystal oscillator time output unit, 310. Crystal oscillator module, 320. Frequency division module, 321. Frequency divider, 322. Counter, PPS1, initial crystal oscillator pulse signal, PPS2, intermediate crystal oscillator pulse signal, PPS', crystal oscillator second pulse signal, PPS, crystal oscillator synchronized second pulse signal, 400. Analysis unit, 500. Selection unit, UTC, world standard time, 20. Sensor unit, 1. Sensor system, 2. Electrical equipment. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0034] See also Figure 1 , Figure 1 FIG. 1 is a schematic diagram of a time synchronization device in an embodiment of the present application. Figure 1 As shown, the present application provides a time synchronization device 10, which includes a satellite signal receiving unit 100, a crystal oscillator time output unit 300 and a synchronization unit 200. The satellite signal receiving unit 100 is used to receive a satellite signal and output at least a satellite second pulse signal 1PPS (1Plus Per Second) according to the satellite signal; the crystal oscillator time output unit 300 is used to output at least a crystal oscillator second pulse signal PPS' and a local crystal oscillator time; the synchronization unit 200 is connected to the satellite signal receiving unit 100 and the crystal oscillator time output unit 300 respectively, and is used to correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time according to the received satellite second pulse signal 1PPS, so that the crystal oscillator time output unit 300 outputs a crystal oscillator synchronized second pulse signal PPS (Plus PerSecond) and a local synchronized crystal oscillator time, wherein the crystal oscillator synchronized second pulse signal PPS is a corrected crystal oscillator second pulse signal PPS', and the local synchronized crystal oscillator time is a corrected local crystal oscillator time.

[0035] Therefore, the above-mentioned time synchronization device 10 in the present application, by configuring the synchronization unit 200 and through the satellite second pulse signal 1PPS output by the satellite signal receiving unit 100, can correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time, so that the crystal oscillator time output unit 300 outputs the crystal oscillator synchronization second pulse signal PPS and the local synchronization crystal oscillator time. When the satellite signal is weak, accurate time is provided locally to meet the time synchronization requirements when the satellite signal is weak.

[0036] Specifically, the crystal oscillator second pulse signal PPS' output by the crystal oscillator time output unit 300 is unstable due to the slight offset and aging of the crystal oscillator, and coupled with the influence of the constantly changing external environment, the cumulative error of the crystal oscillator second pulse signal PPS' will gradually increase, increasingly affecting the accuracy of time synchronization, while the satellite second pulse signal 1PPS output by the satellite signal receiving unit 100 has the characteristics of real-time and high accuracy, but the satellite signal is greatly affected by the external environment. Therefore, when the satellite signal is weak, the satellite second pulse signal 1PPS output by the satellite signal receiving unit 100 can correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time, and provide accurate time locally to meet the time synchronization requirements when the satellite signal is weak.

[0037] See also Figure 2 , Figure 2 FIG. 1 is a schematic diagram of a time synchronization device in another embodiment of the present application. Figure 2 As shown, the satellite signal receiving unit 100 is also used to output timing data, and the crystal oscillator time output unit 300 is also used to output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time; the time synchronization device 10 also includes a parsing unit 400 and a selection unit 500, the parsing unit 400 is connected to the satellite signal receiving unit 100, and the selection unit 500 is respectively connected to the satellite signal receiving unit 100, the parsing unit 400 and the crystal oscillator time output unit 300; wherein, the parsing unit 400 is used to receive the timing data, and parse the timing data to obtain the universal time UTC (Universal Time Coordinated), the selection unit 500 is used to receive the satellite second pulse signal 1PPS, the universal time UTC, the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time, and can selectively output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time, or output the satellite second pulse signal 1PPS and the universal time UTC.

[0038] Thus, by configuring the parsing unit 400 to parse the timing data, the world standard time UTC is obtained, and by configuring the selection unit 500, the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time, or the satellite second pulse signal 1PPS and the world standard time UTC can be selectively output. When the satellite signal is weak, the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time can be output to provide accurate local time, and when the satellite signal is strong, the satellite second pulse signal 1PPS and the world standard time UTC can be output to provide accurate satellite time to meet the time synchronization requirements in various situations.

[0039] In one or more embodiments, the Universal Time UTC includes information such as year, month, day, hour, minute, and second.

[0040] Please also read Figure 3 , Figure 4 , Figure 3 is a schematic diagram of a time synchronization device in another embodiment of the present application, Figure 4 FIG. 1 is a schematic diagram of a crystal oscillator time output unit in an embodiment of the present application. Figure 3 , Figure 4 As shown, the crystal oscillator time output unit 300 includes a crystal oscillator module 310 and a frequency division module 320, the crystal oscillator module 310 is connected to the frequency division module 320, and the frequency division module 320 is respectively connected to the synchronization unit 200 and the selection unit 500; wherein, the crystal oscillator module 310 is used to output the initial crystal oscillator pulse signal PPS1, and the frequency division module 320 is at least used to receive the initial crystal oscillator pulse signal PPS1, divide the initial crystal oscillator pulse signal PPS1 according to the frequency division coefficient to obtain the crystal oscillator second pulse signal PPS', and output the crystal oscillator second pulse signal PPS'.

[0041] Thus, by configuring the crystal oscillator module 310 to output the initial crystal oscillator pulse signal PPS1, and by configuring the frequency division module 320 to divide the initial crystal oscillator pulse signal PPS1 according to the frequency division coefficient to obtain the crystal oscillator second pulse signal PPS', the initial crystal oscillator pulse signal PPS1 output by the crystal oscillator module 310 can be divided according to the required frequency to adapt the frequency of the satellite second pulse signal 1PPS to meet the correction requirements of the satellite second pulse signal 1PPS.

[0042] In one or more embodiments, the crystal oscillator module 310 is a crystal oscillator that provides a stable crystal oscillator frequency through the piezoelectric effect. When mechanical pressure is applied to the surface of the crystal, a voltage proportional to the mechanical pressure appears on the crystal, which causes the crystal to distort. The amount of distortion is proportional to the applied voltage and is proportional to the AC voltage applied to the crystal, causing the crystal to vibrate at its natural frequency, which is the crystal oscillator frequency of the crystal oscillator. The crystal oscillator module 310 can be an oven controlled crystal oscillator (OCXO), model TG-5500CA, with a crystal oscillator frequency of 10MHz, and a stability of the crystal oscillator frequency of 1*10 -9 s, can serve as an excellent crystal oscillator.

[0043] Please also read Figure 5 , Figure 5 FIG. 1 is a schematic diagram of a synchronization unit in an embodiment of the present application. Figure 3 , Figure 5As shown, the synchronization unit 200 includes a comparison module 210 and a frequency division coefficient adjustment module 220. The comparison module 210 is connected to the satellite signal receiving unit 100 and the frequency division module 320 respectively. The comparison module 210 is used to compare the phase of the satellite second pulse signal 1PPS with the phase of the crystal second pulse signal PPS' to obtain a corresponding comparison result signal. The frequency division coefficient adjustment module 220 is used to adjust the frequency division coefficient of the frequency division module 320 according to the comparison result signal to correct the crystal second pulse signal PPS' and the local crystal oscillator time.

[0044] Thus, by configuring the comparison module 210 to compare the phase of the satellite second pulse signal 1PPS with the phase of the crystal oscillator second pulse signal PPS' to obtain a corresponding comparison result signal, and by configuring the frequency division coefficient adjustment module 220 to adjust the frequency division coefficient of the frequency division module 320 according to the comparison result signal to correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time, the frequency division module 320 can output the corrected crystal oscillator second pulse signal PPS' and the local crystal oscillator time to provide accurate local time and meet the time synchronization requirements when the satellite signal is weak.

[0045] In one or more embodiments, the comparison result signal may include the lead and lag conditions of the satellite second pulse signal 1PPS and the crystal oscillator second pulse signal PPS'. The division coefficient adjustment module 220 is used to adjust the division coefficient of the division module 320 according to the lead and lag conditions of the satellite second pulse signal 1PPS and the crystal oscillator second pulse signal PPS' according to a preset adjustment amount, wherein the preset adjustment amount can be set according to specific needs to adjust the division coefficient of the division module 320 in real time to avoid a large difference between the current division coefficient of the division module 320 and the ideal division coefficient.

[0046] In one or more embodiments, the frequency division module 320 may also be configured to output the local crystal oscillator time to the comparison module 210 , so that the local crystal oscillator time is used as the working time of the comparison module 210 .

[0047] Please also read Figure 6 , Figure 6 FIG. 1 is a schematic diagram of a frequency division module in an embodiment of the present application. Figure 3 , Figure 6As shown, the frequency division module 320 includes a frequency divider 321 and a counter 322, the frequency divider 321 is connected to the crystal oscillator module 310, and the counter 322 is connected to the frequency divider 321 and the selection unit 500 respectively; wherein the frequency divider 321 is at least used to divide the initial crystal oscillator pulse signal PPS1 according to the adjusted frequency division coefficient to obtain the corrected intermediate crystal oscillator pulse signal PPS2, the counter 322 is at least used to adjust the pulse width of the corrected intermediate crystal oscillator pulse signal PPS2 to generate a crystal oscillator synchronized second pulse signal PPS, and count the crystal oscillator synchronized second pulse signal PPS to generate a local synchronized crystal oscillator time, and the frequency division module 320 is also used to output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time to the selection unit 500.

[0048] Thus, by configuring the divider 321 to divide the initial crystal oscillator pulse signal PPS1 according to the adjusted division coefficient to obtain the corrected intermediate crystal oscillator pulse signal PPS2, and by configuring the counter 322 to adjust the pulse width of the corrected intermediate crystal oscillator pulse signal PPS2 to generate a crystal oscillator synchronized second pulse signal PPS, and count the crystal oscillator synchronized second pulse signal PPS to generate a local synchronized crystal oscillator time, so that the crystal oscillator time output unit 300 outputs the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time, when the satellite signal is weak, accurate time is provided locally to meet the time synchronization requirements when the satellite signal is weak.

[0049] In one or more embodiments, the counter 322 adjusts the pulse width of the corrected intermediate crystal pulse signal PPS2 to ensure that the high level duration of the crystal synchronization pulse per second signal PPS is the same as the high level duration of the satellite pulse per second signal 1PPS.

[0050] Specifically, the initial count value of the counter 322 is 1, and the counter 322 counts the crystal oscillator synchronized second pulse signal PPS. When the count value of the counter 322 is less than or equal to the threshold, the crystal oscillator synchronized second pulse signal PPS outputs a high level. When the count value of the counter 322 is greater than the threshold, the crystal oscillator synchronized second pulse signal PPS outputs a low level, and the count value of the counter 322 is reset to the initial count value of 1. For example, when the high level duration of the crystal oscillator synchronized second pulse signal PPS is required to be 20ms, and the crystal oscillator frequency of the crystal oscillator module 310 is 10MHz, the threshold can be set to 2000000.

[0051] In one or more embodiments, the counter 322 may include a counter 322, which adjusts the pulse width of the corrected intermediate crystal oscillator pulse signal PPS2 to generate a crystal oscillator synchronized second pulse signal PPS, and at the same time, the counter 322 counts the crystal oscillator synchronized second pulse signal PPS to generate a local synchronized crystal oscillator time. The counter 322 may also include at least two counters 322, one of which adjusts the pulse width of the corrected intermediate crystal oscillator pulse signal PPS2 to generate a crystal oscillator synchronized second pulse signal PPS, and the other counter 322 counts the crystal oscillator synchronized second pulse signal PPS to generate a local synchronized crystal oscillator time, so as to avoid affecting the generation of the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time, and can provide sufficient redundancy when the counter 322 needs to work continuously, so as to avoid failure to output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time as required.

[0052] In one or more embodiments, the divider 321 is also used to divide the initial crystal oscillator pulse signal PPS1 according to the division coefficient before adjustment to obtain an uncorrected intermediate crystal oscillator pulse signal PPS2, and the counter 322 is also used to adjust the pulse width of the uncorrected intermediate crystal oscillator pulse signal PPS2 to generate a crystal oscillator second pulse signal PPS', and count the crystal oscillator second pulse signal PPS' to generate a local crystal oscillator time.

[0053] It should be noted that the above-mentioned crystal oscillator second pulse signal PPS' and crystal oscillator synchronous second pulse signal PPS, local crystal oscillator time and local synchronous crystal oscillator time are only for illustrating the process in which the synchronization unit 200 corrects the crystal oscillator second pulse signal PPS' and the local crystal oscillator time according to the received satellite second pulse signal 1PPS, and for making a naming distinction between the crystal oscillator second pulse signal PPS' and the local crystal oscillator time before and after correction, especially for illustrating the process in which the frequency division coefficient adjustment module 220 in the synchronization unit 200 adjusts the frequency division coefficient of the frequency division module 320 according to the comparison result signal, so as to make a naming distinction between the crystal oscillator second pulse signal PPS' and the local crystal oscillator time obtained by frequency division according to different frequency division coefficients, and does not mean that the crystal oscillator second pulse signal PPS' and the crystal oscillator synchronous second pulse signal PPS, the local crystal oscillator time and the local synchronous crystal oscillator time must be different signals and times.

[0054] That is to say, if Figure 1 , Figure 2 , Figure 3The time synchronization device 10 shown always corrects the crystal oscillator second pulse signal PPS' and the local crystal oscillator time according to the received satellite second pulse signal 1PPS in a correction cycle, so that when the satellite signal is weak, the local area can provide accurate time to meet the time synchronization requirements when the satellite signal is weak, wherein the correction cycle of the time synchronization device 10 can be 1 second. Therefore, at a specific moment, Figure 4 , Figure 6 In the crystal oscillator time output unit 300 shown, the initial crystal oscillator pulse signal PPS1 output by the crystal oscillator module 310 is divided according to the division coefficient at this specific moment to obtain the intermediate crystal oscillator pulse signal PPS2, and the counter 322 adjusts the pulse width of the intermediate crystal oscillator pulse signal PPS2 to generate the same crystal oscillator second pulse signal PPS' / crystal oscillator synchronization second pulse signal PPS, and the counter 322 counts the crystal oscillator second pulse signal PPS' / crystal oscillator synchronization second pulse signal PPS to generate the local crystal oscillator time / local synchronization crystal oscillator time, and then outputs the crystal oscillator second pulse signal PPS' / crystal oscillator synchronization second pulse signal PPS and the local crystal oscillator time / local synchronization crystal oscillator time to the comparison module 210 and the selection unit 500.

[0055] Among them, the frequency division coefficient of the frequency divider 321 at a specific moment is obtained by adjusting the frequency division coefficient adjustment module 220 according to the comparison result signal in the previous cycle of the time synchronization device 10 at a specific moment. That is to say, when there is a phase difference between the satellite second pulse signal 1PPS and the crystal second pulse signal PPS', the frequency division coefficient of the frequency divider 321 of the frequency division module 320 is adjusted, and the frequency divider 321 divides the initial crystal pulse signal PPS1 with the frequency division coefficient adjusted in the previous cycle in the next cycle. When there is no phase difference between the satellite second pulse signal 1PPS and the crystal second pulse signal PPS', the frequency division coefficient of the frequency divider 321 of the frequency division module 320 is not adjusted, and the frequency divider 321 divides the initial crystal pulse signal PPS1 with the same frequency division coefficient in the next cycle.

[0056] In one or more embodiments, the comparison result signal includes the phase difference between the satellite second pulse signal 1PPS and the crystal second pulse signal PPS', and the division coefficient adjustment module 220 is used to adjust the division coefficient of the division module 320 according to the phase difference between the satellite second pulse signal 1PPS and the crystal second pulse signal PPS'.

[0057] Thus, when the comparison result signal not only includes the advance and lag conditions of the satellite second pulse signal 1PPS and the crystal oscillator second pulse signal PPS', but also the phase difference between the satellite second pulse signal 1PPS and the crystal oscillator second pulse signal PPS', by configuring the division coefficient adjustment module 220 to adjust the division coefficient of the division module 320 according to the phase difference between the satellite second pulse signal 1PPS and the crystal oscillator second pulse signal PPS', the phase difference between the satellite second pulse signal 1PPS and the crystal oscillator second pulse signal PPS' can be completely eliminated to provide a more accurate local time. When the satellite signal is weak, the local time can completely replace the satellite time to meet the time synchronization requirements.

[0058] In one or more embodiments, when the phase difference is zero, the frequency division coefficient is equal to the crystal oscillator frequency, and the frequency division coefficient adjustment module 220 does not need to adjust the frequency division coefficient of the frequency division module 320. When the phase difference reaches at least one period of the crystal oscillator second pulse signal PPS', and the phase of the crystal oscillator second pulse signal PPS' leads / lags behind the phase of the satellite second pulse signal 1PPS by τ periods, the frequency division coefficient adjustment module 220 adjusts the frequency division coefficient of the frequency division module 320 to ψ+1, and the crystal oscillator second pulse signal PPS' shifts by one period each time, and shifts continuously for τ periods.

[0059] Please also read Figure 7 , Figure 7 FIG. 1 is a waveform diagram showing the phase comparison of the satellite second pulse signal, the phase pulse signal and the crystal second pulse signal in one embodiment of the present application. Figure 3 , Figure 7 As shown, the synchronization unit 200 also includes a phase pulse generating module 230, which is connected between the satellite signal receiving unit 100 and the comparison module 210. The phase pulse generating module 230 is used to generate a phase pulse signal Ps according to the rising edge of the received satellite second pulse signal 1PPS, and output the phase pulse signal Ps. The phase of the phase pulse signal Ps is the same as the phase of the satellite second pulse signal 1PPS; the comparison module 210 is used to receive the phase pulse signal Ps and the crystal oscillator second pulse signal PPS' output by the frequency division module 320, and compare the phase of the satellite second pulse signal 1PPS with the phase of the crystal oscillator second pulse signal PPS' by comparing the phase of the phase pulse signal Ps with the phase of the crystal oscillator second pulse signal PPS', and obtain a corresponding comparison result signal.

[0060] Therefore, by configuring the phase pulse generating module 230 to generate a phase pulse signal Ps according to the rising edge of the received satellite second pulse signal 1PPS, the phase of the phase pulse signal Ps is compared with the phase of the crystal oscillator second pulse signal PPS' to achieve comparison of the phase of the satellite second pulse signal 1PPS with the phase of the crystal oscillator second pulse signal PPS', and obtain a corresponding comparison result signal.

[0061] Specifically, the phase of the satellite second pulse signal 1PPS is different from the phase of the crystal second pulse signal PPS', and is an asynchronous signal compared to the comparison module 210. Therefore, to find the rising edge moment of the satellite second pulse signal 1PPS, the phase pulse generation module 230 can be used to achieve the phase comparison between the satellite second pulse signal 1PPS and the crystal second pulse signal PPS'. Figure 7 As shown, whenever the rising edge of the satellite second pulse signal 1PPS arrives, the phase pulse generation module 230 generates a phase pulse signal Ps. The pulse width of the phase pulse signal Ps is much smaller than the pulse width of the satellite second pulse signal 1PPS. It can be used as the phase of the satellite second pulse signal 1PPS to compare with the phase of the crystal second pulse signal PPS' and obtain a corresponding comparison result signal.

[0062] In one or more embodiments, the above-mentioned synchronization unit 200 including the phase pulse generation module 230, the comparison module 210, the frequency division coefficient adjustment module 220, the frequency division module 320 of the crystal oscillator time output unit 300, the selection unit 500 and the analysis unit 400 can be arranged as follows: Figure 3 on the control panel shown.

[0063] That is to say, the above-mentioned synchronization unit 200 including the phase pulse generating module 230, the comparison module 210, and the frequency division coefficient adjusting module 220, and the crystal oscillator time output unit 300 including the crystal oscillator module 310 and the frequency division module 320 are merely a logical division method. In another division method, the time synchronization device 10 may also include a satellite signal receiving unit 100, a crystal oscillator module 310 and a control board. The frequency division module 320, the phase pulse generating module 230, the comparison module 210, and the frequency division coefficient adjusting module 220 in the control board may also constitute a digital phase-locked loop.

[0064] Among them, the digital phase-locked loop can control the output signal through the feedback part thereof, and constantly correct the difference between the frequency of the output signal and the frequency of the input signal, so that the phase of the output signal and the input signal is maintained at a relatively fixed relationship. Once the digital phase-locked loop enters the locked state, the phase relationship between the output signal and the input signal can be kept basically unchanged, with only a small random error and no cumulative error. Based on this principle, combining the crystal oscillator second pulse signal PPS' and the local crystal oscillator time with the digital phase-locked loop can reduce the cumulative error of the crystal oscillator second pulse signal PPS' and the local crystal oscillator time, while maintaining a small random error.

[0065] In one or more embodiments, the control board can be a general processor such as a central processing unit (CPU), or a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate logic devices, transistor logic devices and other logic control devices, or a microprocessor such as a micro control unit (MCU). For example, the control board is an FPGA, which is a digital circuit that uses a hardware programming language to program any logic function online, has a complete set of better functions, and has an embedded multiplier, a dedicated external memory interface circuit, an embedded storage module, a digital phase-locked loop and high-speed differential I / O capabilities to meet the correction requirements of the crystal oscillator second pulse signal PPS' and the local crystal oscillator time. Among them, based on the accuracy and cost of time synchronization, the FPGA can use the cyclone V series of Altera.

[0066] Please also read Figure 8 , Figure 8 FIG. 1 is a schematic diagram of a satellite signal receiving unit in an embodiment of the present application. Figure 8 As shown, the satellite signal receiving unit 100 includes a satellite antenna 110 and a satellite receiver 120 connected to each other. The satellite antenna 110 is used to receive satellite signals, and the satellite receiver 120 is used to output satellite pulse-per-second signals 1PPS and timing data.

[0067] Thus, by configuring the antenna to receive satellite signals and by configuring the satellite receiver 120 to at least output the satellite pulse second signal 1PPS and timing data, the crystal oscillator pulse second signal PPS' and the local crystal oscillator time can be corrected, or when the satellite signal is strong, the satellite pulse second signal 1PPS and the world standard time UTC can be output to provide accurate satellite time.

[0068] In one or more embodiments, the satellite signal received by the satellite antenna 110 can be output to the satellite receiver 120 in the form of a radio frequency signal. The satellite receiver 120 can perform signal processing such as frequency conversion and demodulation on the satellite signal, and then output the satellite second pulse signal 1PPS and timing data.

[0069] In one or more embodiments, the received satellite signal may be from a satellite of a satellite navigation system such as a global positioning system (GPS) or BeiDou. For example, when the received satellite signal is from a satellite of a GPS satellite navigation system, the satellite receiver 120 may be a GPS receiver, and the timing data may be NMEA (NationalMarine Electronics Association) data, with a timing accuracy within 100ns, which is very high. Based on the accuracy and cost of time synchronization, the GPS receiver may be the M12MT series of Motorola.

[0070] In one or more embodiments, the selection unit 500 is used to determine the number of satellites sending satellite signals based on the received satellite signals, and when the number of satellites receiving satellite signals at the satellite signal receiving unit 100 is less than 3, the selection unit 500 outputs the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time; when the number of satellites receiving satellite signals at the satellite signal receiving unit 100 is greater than or equal to 3, the selection unit 500 outputs the satellite second pulse signal 1PPS and the world standard time UTC.

[0071] Thus, the strength of the satellite signal is determined according to the number of satellites from which the satellite signal receiving unit 100 receives the satellite signal, and the selection unit 500 is configured to output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time, or to output the satellite second pulse signal 1PPS and the world standard time UTC, so as to meet the time synchronization requirements in various situations.

[0072] Specifically, when the number of satellites receiving satellite signals by the satellite signal receiving unit 100 is less than 3, it is determined that the satellite signal receiving unit 100 is in an abnormal working state, and the satellite signal receiving unit 100 may be in an environment with many buildings, many vegetation covers, and other areas where the satellite signal is weak, and the problem of unstable satellite signals often occurs. When the number of satellites receiving satellite signals by the satellite signal receiving unit 100 is greater than or equal to 3, it is determined that the satellite signal receiving unit 100 is in a normal working state, and the satellite signal receiving unit 100 may be in an open environment where the satellite signal is strong, and the satellite signal is generally stable.

[0073] Among them, when the number of satellites whose satellite signals are received by the satellite signal receiving unit 100 is zero, it can be determined that the satellite signal receiving unit 100 is in a non-working state, and the satellite signal receiving unit 100 may be in an environment without satellite signals such as tunnels and mountainous areas. Since the above-mentioned time synchronization device 10 always corrects the crystal oscillator second pulse signal PPS' and the local crystal oscillator time according to the received satellite second pulse signal 1PPS in a correction period, when there is no satellite signal, the selection unit 500 outputs the crystal oscillator second pulse signal PPS' and the local crystal oscillator time according to the frequency division coefficient adjusted in the previous period, which can basically meet the time synchronization requirements when there is no satellite signal.

[0074] It should be noted that each satellite sends a satellite signal with a different data stamp, which may include the satellite number or other satellite-specific information. Different satellites send different satellite signals. The selection unit 500 determines the number of satellites sending satellite signals based on the number of received satellite signals.

[0075] The time synchronization device 10 of the present application, through the above-mentioned structure, can meet the correction requirements of the satellite second pulse signal 1PPS, so as to correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time according to the satellite second pulse signal 1PPS, so that the crystal oscillator time output unit 300 outputs the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time, and can output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time when the satellite signal is weak, and provide accurate local time, and output the satellite second pulse signal 1PPS and the world standard time UTC when the satellite signal is strong, and provide accurate satellite time, and use the dual backup time of local time without large random errors and satellite time that can provide real-time timing to meet the time synchronization requirements in various situations.

[0076] See also Fig. 9 , Fig. 9 FIG. 1 is a schematic diagram of a sensor system in an embodiment of the present application. Fig. 9 As shown, the present application also provides a sensor system 1, the sensor system 1 includes a time synchronization device 10 and a sensor unit 20 in any of the aforementioned embodiments, the time synchronization device 10 is at least used to correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time provided by the crystal oscillator time output unit 300 when the crystal oscillator time output unit 300 provides the sensor unit 20 with a crystal oscillator second pulse signal PPS' and a local crystal oscillator time.

[0077] like Fig. 9As shown, the time synchronization device 10 includes a satellite signal receiving unit 100, a crystal oscillator time output unit 300 and a synchronization unit 200. The satellite signal receiving unit 100 is used to receive satellite signals and output at least a satellite pulse second signal 1PPS according to the satellite signals; the crystal oscillator time output unit 300 is used to output at least a crystal oscillator pulse second signal PPS' and a local crystal oscillator time; the synchronization unit 200 is connected to the satellite signal receiving unit 100 and the crystal oscillator time output unit 300 respectively, and is used to correct the crystal oscillator pulse second signal PPS' and the local crystal oscillator time according to the received satellite pulse second signal 1PPS, so that the crystal oscillator time output unit 300 outputs a crystal oscillator synchronized pulse second signal PPS and a local synchronized crystal oscillator time, wherein the crystal oscillator synchronized pulse second signal PPS is a corrected crystal oscillator pulse second signal PPS', and the local synchronized crystal oscillator time is a corrected local crystal oscillator time.

[0078] The more specific structure of the time synchronization device 10 can refer to the relevant content of the time synchronization device 10 in any of the aforementioned embodiments, which will not be repeated here.

[0079] Thus, by configuring the time synchronization device 10, at least when the crystal oscillator time output unit 300 provides the sensor unit 20 with the crystal oscillator second pulse signal PPS' and the local crystal oscillator time, the crystal oscillator second pulse signal PPS' and the local crystal oscillator time provided by the crystal oscillator time output unit 300 are corrected, so that the crystal oscillator time output unit 300 outputs the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time. When the satellite signal is weak, accurate time is provided locally to the sensor unit 20, thereby meeting the time synchronization requirement of the sensor system 1 when the satellite signal is weak.

[0080] Specifically, the time synchronization device 10 is also used to correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time provided by the crystal oscillator time output unit 300 when the crystal oscillator time output unit 300 does not provide the sensor unit 20 with the crystal oscillator second pulse signal PPS' and the local crystal oscillator time.

[0081] See also Fig.10 , Fig.10 FIG. 1 is a schematic diagram of a sensor system in another embodiment of the present application. Fig.10 As shown, the time synchronization device 10 is also used to selectively output a crystal oscillator synchronized second pulse signal PPS and a local synchronized crystal oscillator time to the sensor unit 20 , or output a satellite second pulse signal IPPS and a world standard time UTC to the sensor unit 20 .

[0082] Therefore, when the satellite signal is weak, the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time can be output to the sensor unit 20 to provide accurate local time, and when the satellite signal is strong, the satellite second pulse signal 1PPS and the world standard time UTC can be output to the sensor unit 20 to provide accurate satellite time to meet the time synchronization requirements of the sensor system 1 in various situations.

[0083] Specifically, the time synchronization device 10 is also used to correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time provided by the crystal oscillator time output unit 300 when the crystal oscillator time output unit 300 provides the sensor unit 20 with the satellite second pulse signal IPPS and the world standard time UTC.

[0084] In one or more embodiments, the sensor unit 20 includes at least two heterogeneous sensors, and the time synchronization device 10 is also used to selectively output a crystal synchronized second pulse signal PPS and a local synchronized crystal time to at least two heterogeneous sensors, or output a satellite second pulse signal 1PPS and a world standard time UTC to at least two heterogeneous sensors.

[0085] Among them, at least two heterogeneous sensors may be a camera sensor and a millimeter-wave radar sensor. The camera sensor can identify different objects and has a prominent advantage in the measurement accuracy of object height and width. The millimeter-wave radar sensor has a long detection distance, high ranging and speed measurement accuracy, and is not affected by light and weather factors. Therefore, combining the camera sensor and the millimeter-wave radar sensor can improve the perception accuracy of the perceived environment.

[0086] It should be noted that the sampling moments and sampling timestamps of heterogeneous sensors are different, and there is no unified sampling moment and sampling timestamp. The time asynchrony leads to the isolation of the measurement data between heterogeneous sensors, making it difficult to establish associations. Existing heterogeneous sensors are difficult to achieve time synchronization through weighted average method, least square method, interpolation and extrapolation method, Lagrange three-point interpolation and other methods. Especially when at least two heterogeneous sensors are camera sensors and millimeter-wave radar sensors, the advantages of camera sensors and millimeter-wave radar sensors cannot be combined, and false detection and missed detection will occur, which will lead to the sensor system 1 providing wrong information. Therefore, by selecting the rising edge of the crystal oscillator synchronized second pulse signal PPS or the satellite second pulse signal 1PPS as the sampling moment of the heterogeneous sensor, and by selecting the local synchronized crystal oscillator time or the world standard time UTC as the sampling timestamp of the heterogeneous sensor, the fusion between heterogeneous sensors is strengthened, especially the fusion of camera sensors and millimeter-wave radar sensors.

[0087] See also Fig.11 , Fig.11FIG. 1 is a step diagram of a synchronization method for a sensor system in an embodiment of the present application. Fig.11 As shown, the present application also provides a synchronization method of the sensor system 1, and the synchronization method of the sensor system 1 includes:

[0088] Step S200: receiving satellite pulse-per-second signals, timing data, crystal oscillator pulse-per-second signals and local crystal oscillator time;

[0089] Step S210: Correcting the crystal oscillator pulse-per-second signal and the local crystal oscillator time according to the satellite pulse-per-second signal to generate a crystal oscillator synchronized pulse-per-second signal and a local synchronized crystal oscillator time;

[0090] Step S220: Optionally, a crystal oscillator synchronized second pulse signal and a local synchronized crystal oscillator time are output to the sensor unit, or a satellite second pulse signal and a world standard time are output to the sensor unit.

[0091] Thus, the sensor units 20 in the sensor system 1 are hard synchronized in time.

[0092] In one or more embodiments, when the sensor unit 20 includes a camera sensor and a millimeter wave radar sensor, please refer to Fig.12 , Fig.12 FIG. 1 is a step diagram of a synchronization method for a sensor system in another embodiment of the present application. Fig.11 , Fig.12 As shown, after step S220: optionally outputting a crystal oscillator synchronized second pulse signal and a local synchronized crystal oscillator time to the sensor unit, or outputting a satellite second pulse signal and a world standard time to the sensor unit, it also includes:

[0093] Step S300: performing linear regression analysis on the sampling points of the camera sensor and the millimeter wave radar sensor in a preset fusion processing cycle;

[0094] Step S310: establishing a confidence interval and screening fusion points among the sampling points of the camera sensor and the millimeter wave radar sensor;

[0095] Step S320: performing a linear regression analysis on the fusion point to obtain a predicted value of the fusion point of the camera sensor and the millimeter wave radar sensor.

[0096] Therefore, after the sensor units 20 in the sensor system 1 are hard synchronized in time, soft synchronization in time is achieved.

[0097] In one or more embodiments, when the sensor unit 20 includes a camera sensor and a millimeter wave radar sensor, please refer to Fig.13 , Fig.13 FIG. 1 is a step diagram of a synchronization method for a sensor system in another embodiment of the present application. Fig.11 , Fig.13 As shown, before step S200: receiving the satellite pulse-per-second signal, timing data, crystal oscillator pulse-per-second signal and local crystal oscillator time, the method further includes:

[0098] Step S100: establishing a physical coordinate system of the camera sensor and a physical coordinate system of the millimeter wave radar sensor accordingly;

[0099] Step S110: determining the positional relationship between the camera sensor and the millimeter wave radar sensor;

[0100] Step S120: Based on the positional relationship between the camera sensor and the millimeter-wave radar sensor, the physical coordinate system of the camera sensor and the physical coordinate system of the millimeter-wave radar sensor are projected and transformed into the same projection coordinate system.

[0101] Therefore, spatial synchronization is achieved for the sensor units 20 in the sensor system 1 before hard synchronization in time is performed.

[0102] In one or more embodiments, Figure 3 The FPGA or other control board shown executes the above-mentioned synchronization method of the sensor system 1 to synchronize the sensor units 20 in the sensor system 1. For a more specific synchronization method of the sensor system 1, please refer to the relevant content of the sensor system 1 in any of the aforementioned embodiments, which will not be repeated here.

[0103] The time synchronization device 10 and the sensor system 1 of the present application, through the above-mentioned structure, can output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time to the sensor unit 20 to provide accurate local time when the satellite signal is weak, and output the satellite second pulse signal 1PPS and the world standard time UTC to the sensor unit 20 to provide accurate satellite time when the satellite signal is strong, and use the dual backup time of the local time without large random errors and the satellite time that can provide real-time timing to meet the time synchronization requirements of the sensor system 1 in various situations.

[0104] See also Fig.14 , Fig.14 Schematic diagram of an electrical device in an embodiment of the present application. Fig.14 As shown, the present application further provides an electrical device 2, and the electrical device 2 includes the sensor system 1 in any of the aforementioned embodiments.

[0105] like Fig. 9As shown, the sensor system 1 includes the above-mentioned time synchronization device 10 and the sensor unit 20. The time synchronization device 10 is at least used to correct the crystal oscillator second pulse signal PPS' and the local crystal oscillator time provided by the crystal oscillator time output unit 300 when the crystal oscillator time output unit 300 provides the crystal oscillator second pulse signal PPS' and the local crystal oscillator time to the sensor unit 20.

[0106] The more specific structure of the sensor system 1 can refer to the relevant content of the sensor system 1 in any of the aforementioned embodiments, which will not be repeated here.

[0107] Therefore, by synchronizing the time of the sensor system 1 in the electric device 2, the electric device 2 can be kept in a good working state, and defects of the electric device 2 caused by time asynchrony can be avoided.

[0108] In one or more embodiments, the electric device 2 may be a vehicle.

[0109] Specifically, with the development of intelligent driving technology, the sensors in the sensor system 1 carried by the vehicle are more diverse, and higher requirements are put forward for the perception fusion between the sensors of intelligent driving, especially when the sensor unit 20 includes at least two heterogeneous sensors, and at least two heterogeneous sensors are a camera sensor and a millimeter-wave radar sensor. If the advantages of the camera sensor and the millimeter-wave radar sensor cannot be combined, false detection and missed detection will occur, resulting in misjudgment of the vehicle's decision, causing unreasonable acceleration, deceleration and braking of the vehicle during the intelligent driving process, which is easy to cause traffic safety accidents. Through the time synchronization of the sensor system 1, the vehicle can maintain a good working state during the intelligent driving process.

[0110] The time synchronization device 10, sensor system 1 and electrical equipment 2 of the present application, through the above-mentioned structure, can output the crystal oscillator synchronized second pulse signal PPS and the local synchronized crystal oscillator time to the sensor unit 20 to provide accurate local time when the satellite signal is weak, and output the satellite second pulse signal 1PPS and the world standard time UTC to the sensor unit 20 to provide accurate satellite time when the satellite signal is strong, and utilize the dual backup time of the local time without large random errors and the satellite time that can provide real-time timing to meet the time synchronization requirements of the sensor system 1 in various situations, so that the electrical equipment 2 can maintain a good working state and avoid defects of the electrical equipment 2 caused by time asynchrony.

[0111] The above description is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application; in the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A time synchronization device, characterized in that: include: A satellite signal receiving unit, configured to receive a satellite signal and output at least a satellite pulse-second signal according to the satellite signal; A crystal oscillator time output unit, at least used to output a crystal oscillator second pulse signal and a local crystal oscillator time; as well as A synchronization unit is respectively connected to the satellite signal receiving unit and the crystal oscillator time output unit, and is used to correct the crystal oscillator second pulse signal and the local crystal oscillator time according to the received satellite second pulse signal, so that the crystal oscillator time output unit outputs a crystal oscillator synchronization second pulse signal and a local synchronization crystal oscillator time, wherein the crystal oscillator synchronization second pulse signal is the corrected crystal oscillator second pulse signal, and the local synchronization crystal oscillator time is the corrected local crystal oscillator time.

2. The time synchronization device according to claim 1, characterized in that: The satellite signal receiving unit is also used to output timing data, and the crystal oscillator time output unit is also used to output the crystal oscillator synchronous second pulse signal and the local synchronous crystal oscillator time; The time synchronization device further comprises a parsing unit and a selecting unit, wherein the parsing unit is connected to the satellite signal receiving unit, and the selecting unit is respectively connected to the satellite signal receiving unit, the parsing unit and the crystal oscillator time output unit; Among them, the analysis unit is used to receive the timing data and analyze the timing data to obtain the world standard time. The selection unit is used to receive the satellite second pulse signal, the world standard time, the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time, and can selectively output the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time, or output the satellite second pulse signal and the world standard time.

3. The time synchronization device according to claim 2, characterized in that: The crystal oscillator time output unit includes a crystal oscillator module and a frequency division module, the crystal oscillator module is connected to the frequency division module, and the frequency division module is connected to the synchronization unit and the selection unit respectively; Among them, the crystal oscillator module is used to output an initial crystal oscillator pulse signal, and the frequency division module is at least used to receive the initial crystal oscillator pulse signal, divide the initial crystal oscillator pulse signal according to the frequency division coefficient to obtain the crystal oscillator second pulse signal, and output the crystal oscillator second pulse signal.

4. The time synchronization device according to claim 3, characterized in that: The synchronization unit includes a comparison module and a frequency division coefficient adjustment module. The comparison module is connected to the satellite signal receiving unit and the frequency division module respectively. The comparison module is used to compare the phase of the satellite second pulse signal with the phase of the crystal oscillator second pulse signal to obtain a corresponding comparison result signal. The frequency division coefficient adjustment module is used to adjust the frequency division coefficient of the frequency division module according to the comparison result signal to correct the crystal oscillator second pulse signal and the local crystal oscillator time.

5. The time synchronization device according to claim 4, characterized in that: The frequency division module includes a frequency divider and a counter, the frequency divider is connected to the crystal oscillator module, and the counter is connected to the frequency divider and the selection unit respectively; Among them, the divider is at least used to divide the initial crystal oscillator pulse signal according to the adjusted division coefficient to obtain a corrected intermediate crystal oscillator pulse signal, the counter is at least used to adjust the pulse width of the corrected intermediate crystal oscillator pulse signal to generate the crystal oscillator synchronized second pulse signal, and count the crystal oscillator synchronized second pulse signal to generate the local synchronized crystal oscillator time, and the division module is also used to output the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time to the selection unit.

6. The time synchronization device according to claim 4, characterized in that: The comparison result signal includes the phase difference between the satellite second pulse signal and the crystal second pulse signal, and the frequency division coefficient adjustment module is used to adjust the frequency division coefficient of the frequency division module according to the phase difference between the satellite second pulse signal and the crystal second pulse signal.

7. The time synchronization device according to claim 4, characterized in that: The synchronization unit further includes a phase pulse generating module, which is connected between the satellite signal receiving unit and the comparison module, and is used to generate a phase pulse signal according to the rising edge of the received satellite second pulse signal, and output the phase pulse signal, wherein the phase of the phase pulse signal is the same as the phase of the satellite second pulse signal; The comparison module is used to receive the phase pulse signal and the crystal oscillator second pulse signal output by the frequency division module, and compare the phase of the satellite second pulse signal with the phase of the crystal oscillator second pulse signal by comparing the phase of the phase pulse signal with the phase of the crystal oscillator second pulse signal, and obtain a corresponding comparison result signal.

8. The time synchronization device according to claim 2, characterized in that: The selection unit is used to determine the number of satellites that send the satellite signal according to the received satellite signal, and when the number of satellites whose satellite signals are received by the satellite signal receiving unit is less than 3, the selection unit outputs the crystal oscillator synchronized second pulse signal and the local synchronized crystal oscillator time; When the number of satellites from which the satellite signal receiving unit receives satellite signals is greater than or equal to 3, the selection unit outputs the satellite second pulse signal and the universal time.

9. A sensor system, comprising the time synchronization device according to any one of claims 1 to 8 and a sensor unit, characterized in that: The time synchronization device is at least used for correcting the crystal oscillator second pulse signal and the local crystal oscillator time provided by the crystal oscillator time output unit when the crystal oscillator time output unit provides the crystal oscillator second pulse signal and the local crystal oscillator time to the sensor unit.

10. An electrical device, characterized in that: Comprising the sensor system of claim 9.

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