WO2021237733A1

WO2021237733A1 - Synchronization method, movable platform, control terminal and synchronization system

Info

Publication number: WO2021237733A1
Application number: PCT/CN2020/093509
Authority: WO
Inventors: 饶雄斌; 陈颖; 邓任钦
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2020-05-29
Filing date: 2020-05-29
Publication date: 2021-12-02

Abstract

A synchronization method, a movable platform, a control terminal and a synchronization system. The synchronization method comprises that: a communication module of the movable platform receives second pulses sent by a satellite positioning module of the movable platform at a specified time interval, and records the time when the second pulses arrive; a clock signal of the movable platform is calibrated according to the time when the second pulses arrive and the specified time interval; on the basis of the calibrated clock signal, a reference signal is sent to the control terminal; and the control terminal calibrates a clock signal of the control terminal according to the reference signal so as to synchronize the clock signals of the movable platform and the control terminal. In the present embodiment, a satellite positioning module with relatively high time precision is used to synchronize the clock signals of the communication modules of the movable platform and/or the control terminal, which may simplify the synchronization process between the two.

Description

Synchronization method, movable platform, control terminal and synchronization system

Technical field

This application relates to the field of communication technology, and specifically, to a synchronization method, a movable platform, a control terminal, and a synchronization system.

Background technique

With the development of technology, mobile platforms (such as unmanned aerial vehicles, mobile robots, etc.) have gradually become popular in people’s lives. In order to further improve the market competitiveness of mobile platforms, businesses usually reduce the cost of mobile platform components. Cost controls the selling price of the mobile platform. Among them, the crystal oscillator used in the wireless communication system of the mobile platform is an object of cost reduction.

However, generally speaking, the lower the price of the crystal oscillator, the greater the deviation between the frequency of the crystal oscillator and the nominal value. When the frequency of the sender is inconsistent with the frequency of the receiver, or the difference is too large, the receiver cannot receive and demodulate correctly. The data sent by the sender. Therefore, how to achieve accurate synchronization between the sending end and the receiving end when the quality of the crystal oscillator is low has become an urgent problem to be solved.

Summary of the invention

In view of this, one of the objectives of this application is to provide a synchronization method, a movable platform, a control terminal, and a synchronization system.

In the first aspect, an embodiment of the present application provides a synchronization system, including a movable platform and a control terminal, and a communication connection is established between the movable platform and the control terminal;

The mobile platform is equipped with a communication module and a satellite positioning module;

The communication module of the movable platform is used to: receive the second pulse sent by the satellite positioning module of the movable platform at a specified time interval, and record the arrival time of the second pulse; according to the arrival time and the time of the second pulse Calibrate the clock signal of the movable platform at the specified time interval; send a reference signal to the control terminal based on the calibrated clock signal;

The control terminal is used to calibrate the clock signal of the control terminal according to the reference signal, so as to synchronize the clock signal of the movable platform and the control terminal.

In the second aspect, the embodiments of the present application provide a synchronization method, which is applied to a synchronization system. The synchronization system includes a movable platform and a control terminal. A communication connection is established between the movable platform and the control terminal. The mobile platform is equipped with a communication module and a satellite positioning module, and the method includes:

The communication module of the movable platform receives the second pulse sent by the satellite positioning module of the movable platform at a specified time interval, and records the arrival time of the second pulse; according to the arrival time of the second pulse and the specified time Interval, calibrate the clock signal of the movable platform; send a reference signal to the control terminal based on the calibrated clock signal;

The control terminal calibrates the clock signal of the control terminal according to the reference signal to synchronize the clock signal of the movable platform and the control terminal.

In the third aspect, an embodiment of the present application provides a movable platform, including:

body;

The power system is located inside the fuselage and provides power for the movable platform;

The satellite positioning module is arranged inside the fuselage and is used to send a second pulse to the communication module at a specified time interval;

The communication module is arranged inside the fuselage and is used to perform the following steps:

Receiving the second pulse, and recording the arrival time of the second pulse;

Calibrate the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval;

Based on the calibrated clock signal, a reference signal is sent to the control terminal of the movable platform, and the reference signal is used to synchronize the clock signal of the movable platform and the control terminal.

In a fourth aspect, an embodiment of the present application provides a synchronization method, which is applied to a movable platform, and a communication connection is established between the movable platform and a control terminal, and the method includes:

Receiving the second pulse sent by the satellite positioning module of the mobile platform at a specified time interval, and recording the arrival time of the second pulse;

Based on the calibrated clock signal, a reference signal is sent to the control terminal; the reference signal is used to synchronize the clock signal of the movable platform and the control terminal.

In the fifth aspect, an embodiment of the present application provides a control terminal, including a satellite synchronization module and a communication module;

The satellite positioning module is configured to: send a second pulse to the communication module at a specified time interval;

The communication module is used for:

Receiving the second pulse, and recording the arrival time of the second pulse;

Perform preliminary calibration on the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval;

The pre-calibrated clock signal is further calibrated according to the reference signal received from the movable platform to synchronize the clock signal of the movable platform and the control terminal.

In a sixth aspect, an embodiment of the present application provides a synchronization method, which is applied to a control terminal, and a communication connection is established between the control terminal and a movable platform, and the method includes:

Receiving the second pulse sent by the satellite positioning module of the control terminal at a specified time interval, and recording the arrival time of the second pulse;

An embodiment of the application provides a synchronization method, a movable platform, a control terminal, and a synchronization system. The satellite positioning module with high time accuracy is used to calibrate the clock signal of the communication module of the movable platform. The communication module of the movable platform receives the second pulse sent by the satellite positioning module of the movable platform at a specified time interval and records the second. Pulse arrival time, and then calibrate the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval; so that the clock signal of the communication module of the movable platform can be aligned with the clock signal of the satellite positioning module, that is, The communication module of the movable platform has undergone preliminary calibration, and when the communication module of the movable platform is synchronized with the communication module of the control terminal, the clock signal based on the preliminary calibration can simplify the synchronization process between the two, improve synchronization efficiency, and Because the satellite positioning module has high time accuracy, it can ensure accurate synchronization between the two on the basis of simplifying the synchronization process.

Description of the drawings

In order to explain the technical solutions in the embodiments of the present application more clearly, the following will briefly introduce the drawings needed in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

FIG. 1 is a schematic diagram of a synchronization system provided by an embodiment of the present application;

Figure 2 is a schematic diagram of a second synchronization system provided by an embodiment of the present application;

FIG. 3 is a schematic diagram of signal interaction between a movable platform and a control terminal provided by an embodiment of the present application;

4 is another schematic diagram of signal interaction between a movable platform and a control terminal provided by an embodiment of the present application;

Figure 5 is a schematic diagram of a third synchronization system provided by an embodiment of the present application;

Fig. 6 is a schematic diagram of signal interaction in a synchronization system provided by an embodiment of the present application;

FIG. 7 is another schematic diagram of signal interaction in a synchronization system provided by an embodiment of the present application;

FIG. 8 is a schematic diagram of a synchronization method provided by an embodiment of the present application;

FIG. 9 is a schematic diagram of a movable platform provided by an embodiment of the present application;

FIG. 10 is a schematic diagram of another synchronization method provided by an embodiment of the present application;

FIG. 11 is a schematic diagram of a control terminal provided by an embodiment of the present application;

FIG. 12 is a schematic diagram of another synchronization method provided by an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by a person of ordinary skill in the art without creative work shall fall within the protection scope of this application.

Based on the problems in the prior art, the embodiments of the present application provide a synchronization method, a synchronization system, a movable platform, and a control terminal. A satellite positioning module with higher time accuracy is used to control the mobile platform and/or control terminal. The clock signal of the communication module is synchronized so that the clock signal of the communication module of the mobile platform and/or the control terminal can be aligned with the clock signal of the satellite positioning module, that is, the communication module of the mobile platform and/or the control terminal has been When the communication module of the mobile platform is synchronized with the communication module of the control terminal, the clock signal based on the preliminary calibration can simplify the synchronization process between the two, improve the synchronization efficiency, and because the satellite positioning module has a higher time Accuracy makes it possible to ensure precise synchronization between the two on the basis of simplifying the synchronization process.

Next, an exemplary description of the clock signal synchronization process between the communication module of the movable platform and the communication module of the control terminal by using the satellite positioning module will be explained. The crystal oscillators on the mobile platform and the control terminal are generated separately, and the clock signal synchronization between the mobile platform and the control terminal is the basis for ensuring that the two can correctly send and receive data:

Please refer to FIG. 1, which is a structural diagram of a synchronization system shown in an exemplary embodiment of this application. The synchronization system includes a movable platform 20 and a control terminal 30, and a communication connection is established between the movable platform 20 and the control terminal 30. The movable platform 20 includes, but is not limited to, unmanned aerial vehicles, unmanned vehicles, unmanned ships, or mobile robots, etc., and the control terminal 30 includes, but is not limited to, remote control mobile phones, computers, personal tablets, or smart wearable devices ( Such as smart glasses) and so on.

The movable platform 20 is installed with a communication module 21. The mobile platform 20 establishes a communication connection with the control terminal 30 through a communication module 21 installed by itself. It is understandable that the embodiment of the present application does not impose any restrictions on the communication protocol applied for the communication connection between the movable platform 20 and the control terminal 30, and specific settings can be made according to actual application scenarios. In an example, the communication protocol applied by the communication module 21 of the movable platform 20 includes but is not limited to a mobile communication network protocol or a near field communication protocol, and the mobile communication network protocol includes but is not limited to a 3G/4G/5G protocol. Etc., the near field communication protocol includes, but is not limited to, Bluetooth protocol, Wi-Fi protocol, UWB protocol, or infrared communication protocol.

The mobile platform 20 is also installed with a satellite positioning module 22. It is understandable that the embodiment of the present application does not impose any restriction on the specific type of the satellite positioning module 22, and specific selections can be made according to actual application scenarios. In an example, the satellite positioning module 22 includes, but is not limited to, a GNSS (Global Navigation Satellite System, Global Navigation Satellite System) module or a GPS (Global Positioning System, Global Positioning System) module, etc.

Wherein, because the high time accuracy attribute of the satellite positioning module is used to assist the clock signal synchronization between the movable platform 20 and the control terminal 30, therefore, in this embodiment, the satellite of the movable platform 20 The positioning module 22 is connected to the communication module 21. Optionally, the high time accuracy attribute of the satellite positioning module 22 may be reflected in the second pulse output thereof. Therefore, in the movable platform 20, the second pulse port of the satellite positioning module 22 may be connected to the second pulse port of the satellite positioning module 22. The communication module 21 is connected, so that the communication module 21 of the movable platform 20 can calibrate the clock signal with the aid of the second pulse output by the satellite positioning module 22. It is understandable that this embodiment does not impose any restriction on the connection mode between the second pulse port and the communication module 21. For example, the second pulse port can be used through a GPIO interface (General-purpose input/output, general-purpose input/output).的input and output) are connected to the communication module 21.

During synchronization, after the satellite positioning module 22 of the movable platform 20 completes satellite search, the satellite positioning module 22 sends a second pulse to the communication module 21 of the movable platform 20 at a specified time interval; The communication module 21 of the mobile platform 20 receives the second pulse sent by the satellite positioning module 22 of the mobile platform 20 at a specified time interval, and records the arrival time of the second pulse; then according to the arrival time of the second pulse and the At a specified time interval, the clock signal of the movable platform 20 is calibrated; finally based on the calibrated clock signal, a reference signal is sent to the control terminal 30; the reference signal is used to synchronize the movable platform 20 with all The clock signal of the control terminal 30 is described.

It should be understood that this embodiment does not impose any restriction on the specified time interval, and an appropriate time length can be set according to actual application scenarios. In a possible implementation, the specified time interval may be an integer multiple of the reference signal transmission period, so as to ensure the accuracy of clock signal calibration performed by the mobile platform 20 using the satellite positioning module 22.

In one embodiment, when calibrating the clock signal of the movable platform 20, the communication module 21 of the movable platform 20 specifically determines the The frequency offset and/or time offset of the clock signal of the movable platform 20; and then the clock signal of the movable platform is calibrated according to the frequency offset and/or time offset. Wherein, and/or means two or one of both.

Wherein, the frequency offset represents the difference between the actual clock signal frequency and the ideal clock signal frequency; the frequency offset is based on the time difference between the M second pulses arriving at the communication module 21 and the M The second pulse is determined by the relative relationship of the time difference sent from the satellite positioning module 22; M is an integer; the time difference of the M second pulses sent from the satellite positioning module 22 is determined based on the specified time interval. In an example, it is assumed that the satellite positioning module 22 of the movable platform 20 sends a second pulse to the communication module 21 of the movable platform 20 _{at a time interval T g. It is assumed that the communication module 21 of the movable platform 20 receives n} The time for n consecutive second pulses to reach the communication module 21 of the movable platform 20 is {T ₁ , T ₂ , T ₃ ,...T _n }, n is an integer, let The frequency offset of the clock signal of the movable platform 20 is A, then

Among them, the unit of A is ppm (parts per million).

Wherein, the time offset represents the time difference between the actual clock signal and the ideal clock signal at the corresponding effective instant (generally referred to as the rising edge or the falling edge). The time offset is the result of the remainder calculation between the time when the second pulse arrives at the communication module 21 and the specified time interval. Assuming that the time offset of the clock signal of the movable platform 20 is B, then

Further, the movable platform 2 performs alpha filtering on the time offset, and then calibrates the clock signal of the communication module 21 of the movable platform 2 according to the value after the alpha filtering.

After the communication module 21 of the movable platform 20 calibrates its own clock signal, based on the calibrated clock signal, it sends a reference signal to the control terminal 30, and then the control terminal 30 controls the control terminal 30 according to the reference signal. The clock signal of the terminal 30 is calibrated to synchronize the clock signal of the movable platform 20 and the control terminal 30.

In an embodiment, referring to FIG. 2, the control terminal 30 is installed with a communication module 31 and a satellite positioning module 32. The communication module 21 of the movable platform 20 and the communication module 31 of the control terminal 30 establish a communication connection. The communication module 31 of the control terminal 30 is connected to the satellite positioning module 32 of the control terminal 30 so that the communication module 31 of the control terminal 30 uses the satellite positioning module 32 of the control terminal 30 to perform preliminary calibration. In an example, the satellite positioning module 32 includes, but is not limited to, a GNSS module or a GPS module. Optionally, the high time accuracy attribute of the satellite positioning module 32 may be reflected in the second pulse output thereof. Therefore, in the control terminal 30, the second pulse port of the satellite positioning module 32 may be connected to the second pulse port of the satellite positioning module 32. The communication module 31 is connected.

In the embodiment shown in FIG. 2, during synchronization, after the satellite positioning module 32 of the control terminal 30 completes satellite search, the satellite positioning module 32 sends a notification to the communication module 31 of the control terminal 30 at a specified time interval. Send a second pulse; the communication module 31 of the control terminal 30 receives the second pulse sent by the satellite positioning module 32 of the control terminal 30 at a specified time interval, and records the arrival time of the second pulse, and then according to the second pulse arrival The clock signal of the control terminal 30 is preliminarily calibrated at the time and the specified time interval; and the preliminarily calibrated clock signal is further calibrated according to the reference signal sent by the movable platform 20 to synchronize the The clock signal of the movable platform 20 and the control terminal 30. In this embodiment, since the communication module 21 of the movable platform 20 and the communication module 31 of the control terminal 30 are both calibrated according to the clock signal of the satellite positioning system, the error of the misalignment of the two clock signals becomes Therefore, when the communication module 31 of the control terminal 30 uses the reference signal to further calibrate the pre-calibrated clock signal, there is no need to perform coarse frequency synchronization and/or coarse time synchronization synchronization procedures. The synchronization process of fine frequency synchronization and/or fine time synchronization is required, which greatly simplifies the synchronization process and also ensures the accuracy of the synchronization result.

In an implementation manner, when performing preliminary calibration of the clock signal of the control terminal 30, the communication module 31 of the control terminal 30 determines the control terminal 30 according to the arrival time of the second pulse and the specified time interval The frequency offset and/or time offset of the clock signal of the terminal 30; then, the clock signal of the movable platform is preliminarily calibrated according to the frequency offset and/or time offset.

Wherein, the frequency offset represents the difference between the actual clock signal frequency and the ideal clock signal frequency; the frequency offset is based on the time difference between the M second pulses arriving at the communication module 31 and the M The second pulse is determined by the relative relationship of the time difference sent from the satellite positioning module 32; M is an integer; the time difference of the M second pulses sent from the satellite positioning module 32 is determined based on the specified time interval. In an example, it is assumed that the satellite positioning module 32 of the control terminal 30 sends a second pulse to the communication module 31 of the control terminal 30 _{at a time interval T g. It is assumed that the communication module 31 of the control terminal 30 receives n consecutive} Second pulse, the time for n consecutive second pulses to reach the communication module 31 of the control terminal 30 are {T ₁ , T ₂ , T ₃ ,...T _n }, and n is an integer. Let the control terminal The frequency offset of the clock signal of 30 is A, then

Among them, the unit of A is ppm (parts per million).

Wherein, the time offset characterizes the delay time between the actual clock signal and the ideal clock signal at the corresponding effective instant (generally referred to as the rising edge or the falling edge). The time offset is the result of the remainder operation between the time when the second pulse arrives at the communication module 31 and the specified time interval. Assuming that the time offset of the clock signal of the control terminal 30 is B, then

Further, the control terminal 30 performs alpha filtering on the time offset, and then calibrates the clock signal of the communication module 31 of the control terminal 30 according to the value after the alpha filtering.

Next, the process of further calibrating the pre-calibrated clock signal by the communication module 31 of the control terminal 30 according to the reference signal will be described:

In the first implementation manner, the reference signal includes N reference signals sent periodically; N is an integer; when the clock signal after preliminary calibration is further calibrated according to the reference signal, the control terminal 30 The communication module 31 calibrates the clock signal of the control terminal 30 according to the difference between the time difference between the N reference signals sent by the movable platform 20 and the time difference between the N reference signals received by the control terminal 30 .

For example, referring to FIG. 3, the reference signal carries the time tN when the mobile platform 20 sends the reference signal. When the communication module 31 of the control terminal 30 receives the reference signal, it records the time tN received. The time tN′ of the reference signal, where N is an integer, then after the mobile platform 20 sends N reference signals and the communication module 31 of the control terminal 30 receives the N reference signals, the communication module of the control terminal 30 31. The time difference between the mobile platform 20 sending the N reference signals and the time difference between the control terminal 30 receiving the N reference signals can be obtained; in the same time interval, if the mobile platform 20 sends the N reference signals The time difference of the N reference signals is the same as the time difference of the control terminal 30 receiving the N reference signals, which means that the clock signal between the movable platform and the control terminal 30 is synchronized. The difference between, and the clock signal of the control terminal 30 is calibrated.

In the second implementation manner, the communication module 31 of the control terminal 30 is further configured to send a response signal to the movable platform 20 according to the reference signal; when the clock signal after preliminary calibration is compared according to the reference signal When performing further calibration, the communication module 31 of the control terminal 30 determines the movable platform 20 and the control terminal 30 according to the sending time and receiving time of the reference signal and the sending time and receiving time of the response signal. The time deviation between the two to calibrate the clock signal of the control terminal 30.

For example, referring to FIG. 4, the movable platform 20 sends a first reference signal to the communication module 31 of the control terminal 30, and the reference signal carries the time when the movable platform 20 sends the reference signal. After the communication module 31 of the control terminal 30 receives the first reference signal, it can learn the time when the mobile platform 20 sends the first reference signal and the time when the control terminal 30 receives the first reference signal, Next, the communication module 31 of the control terminal 30 sends a response signal to the movable platform 20 according to the first reference signal, and records the time when the response signal is sent. The movable platform 20 can be based on the response The signal sends a second reference signal to the communication module 31 of the control terminal 30. The second reference signal carries the time when the mobile platform 20 receives the response signal. Suppose the mobile platform 20 sends the first reference signal. The time of the reference signal is t ₁ , the time when the control terminal 30 receives the first reference signal is t ₂ , the time when the control terminal 30 sends the response signal is t ₃ , and the movable platform 20 receives all The time of the response signal is t ₄ , and the time deviation between the movable platform 20 and the control terminal 30 is t, then

In a third implementation manner, the reference signal includes pilot symbols, and when the pre-calibrated clock signal is further calibrated according to the reference signal, the communication module 31 of the control terminal 30 obtains the time domain phase. The first frequency domain received signal and the second frequency domain received signal corresponding to the two adjacent reference signals obtain the first frequency domain channel value according to the first frequency domain received signal and the pilot symbol, and the first frequency domain channel value is obtained according to the second frequency domain. Domain received signal and the pilot symbol to obtain a second frequency domain channel value; time domain transform is performed on the first frequency domain channel value to obtain a first time domain channel impulse response, and the second frequency domain channel value is Time domain transformation is used to obtain a second time domain channel impulse response; the first time domain channel impulse response is determined according to the energy value of the first time domain channel impulse response and the second time domain channel impulse response The first target response data of the first target response data, and the second target response data of the second time domain channel impulse response; the clock signal of the control terminal 30 according to the first target response data and the second target response data Perform calibration. This embodiment uses the first target response data and the second target response data to estimate the carrier frequency offset to obtain the frequency offset, which can reduce the frequency offset estimation when the signal-to-noise ratio is low and the interference signal is strong. Errors ensure the correctness of the clock signal synchronization between the movable platform 20 and the control terminal 30.

Wherein, the pilot symbol corresponding to the first frequency domain received signal and the pilot symbol corresponding to the second frequency domain received signal may be the same or different. The two adjacent reference signals in the time domain refer to the two reference signals containing pilot symbols transmitted by the movable platform 20 at a preset time interval. The preset time interval may be S*T, and S is two reference signals containing pilot symbols. The number of reference signals that do not include the pilot symbol in the interval between the reference signals of the pilot symbol, and T is the time length occupied by each reference signal. The reference signal may include non-pilot symbol data and/or pilot symbols. And/or means two or one of both.

Optionally, the communication module 31 of the control terminal 30 obtains the first frequency domain channel value according to the least squares estimation of the first frequency domain received signal and the pilot symbol as the frequency domain channel value, and the second frequency domain received signal Do the least square estimation of the frequency domain channel value with the pilot symbol to obtain the second frequency domain channel value. The calculation method of the least square estimation is to make the ratio of the frequency domain received signal and the pilot symbol to obtain the frequency domain channel value.

Optionally, the communication module 31 of the control terminal 30 first composes the first frequency domain channel value into a first frequency domain vector according to preset pilot symbols, and composes the second frequency domain channel value according to the preset pilot symbols into a second frequency domain vector. Frequency domain vector, and then the first frequency domain vector is subjected to inverse Fourier transform to obtain the first time domain channel impulse response, and the second frequency domain vector is subjected to inverse Fourier transform to obtain the second time domain channel impulse response.

Optionally, the first target response data includes 2L+1 response data, the second target response data includes 2L+1 response data, and the L is a natural number. The L is determined according to the signal-to-noise ratio. The L+1th response data in the first target response data corresponds to when the sum of the energy of the first time domain channel impulse response and the energy of the corresponding second time domain channel impulse response is the maximum The first time domain channel impulse response data in the second target response data, the L+1th response data in the second target response data is the energy of the first time domain channel impulse response and the corresponding second time domain channel The second time domain channel impulse response data corresponding to the maximum sum of the energy of the impulse response.

Optionally, after the communication module 31 of the control terminal 30 obtains the first target response data and the second target response data, it performs carrier frequency offset estimation based on the first target response data and the second target response data to obtain the first frequency The frequency offset of the received signal in the second frequency domain and the subframe to which the received signal in the second frequency domain belongs, and then further calibrates the preliminarily calibrated clock signal based on the frequency offset. Among them, the first target response data only includes the 2L+1 first time domain channel impulse response data in the first time domain channel impulse response, and the second target response data also includes only the second time domain channel impulse response data. 2L+1 second time-domain channel impulse response data, so when the signal-to-noise ratio is low and the interference signal is strong, the receiving device performs carrier frequency offset according to the first target response data and the second target response data The estimated frequency offset error is small, and it can resist extremely low signal-to-noise ratio and anti-interference signals.

In another embodiment, referring to FIG. 5, the control terminal 30 is equipped with a communication module 31 but not a satellite positioning module 32. At this time, the control terminal 30 controls the control terminal according to the reference signal. The clock signal of 30 is calibrated to synchronize the clock signal of the movable platform 20 and the control terminal 30. In this embodiment, since the communication module 21 of the movable platform 20 is synchronized with the clock signal of the satellite positioning system, that is to say, the clock signal of the movable platform 20 has been calibrated, so only the calibration is required. Controlling the clock signal of the communication module 31 of the terminal 30 greatly simplifies the synchronization process and also ensures the accuracy of the synchronization result.

In a possible implementation, the reference signal includes N reference signals sent periodically; N is an integer; when the clock signal of the control terminal 30 is calibrated according to the reference signal, the control terminal The communication module 31 of 30 performs processing on the clock signal of the control terminal 30 according to the difference between the time difference between the mobile platform 20 sending the N reference signals and the time difference between the control terminal 30 receiving the N reference signals calibration.

In a possible implementation manner, the control terminal 30 is further configured to send a response signal to the movable platform 20 according to the reference signal; when the clock signal of the control terminal 30 is calibrated according to the reference signal When the time, the communication module 31 of the control terminal 30 determines the distance between the movable platform 20 and the control terminal 30 according to the sending time and receiving time of the reference signal, and the sending time and receiving time of the response signal. The time deviation is used to calibrate the clock signal of the control terminal 30.

In a possible implementation manner, the reference signal includes pilot symbols, and when the clock signal of the control terminal 30 is calibrated according to the reference signal, the control terminal 30 is specifically configured to: obtain the time domain The first frequency domain received signal and the second frequency domain received signal corresponding to the two adjacent reference signals obtain the first frequency domain channel value according to the first frequency domain received signal and the pilot symbol, and according to the second frequency domain channel value The frequency domain received signal and the pilot symbol are used to obtain a second frequency domain channel value; the first frequency domain channel value is subjected to time domain transformation to obtain a first time domain channel impulse response, and the second frequency domain channel value Perform time domain transformation to obtain a second time domain channel impulse response; determine the first time domain channel impulse response according to the energy value of the first time domain channel impulse response and the second time domain channel impulse response The first target response data of the response and the second target response data of the second time domain channel impulse response; the clock of the control terminal 30 is updated according to the first target response data and the second target response data The signal is calibrated.

In addition, it is considered that after the clock signals of the movable platform 20 and the control terminal 30 are synchronized for the first time, although the clock signals of the movable platform 20 and the control terminal 30 will be synchronized within a period of time, the crystal oscillator has Drift characteristics, coupled with the influence of other factors such as temperature, make the clock signals of the movable platform 20 and the control terminal 30 may have a time offset after a period of time. Therefore, the movable platform is synchronized for the first time. After the clock signal 20 and the control terminal 30, the communication module 21 of the movable platform 20 also needs to use the second pulse sent by its own satellite positioning module 22 to re-determine the time offset, and then re-determine the time offset based on the re-determined time offset. The clock signal of the movable platform 20 is calibrated. For the specific implementation process, please refer to the calibration process of the clock signal of the movable platform 20 described above, which will not be repeated here.

In the embodiment shown in FIG. 2, the control terminal 30 is equipped with a satellite positioning module 32. Based on the drift characteristics of the crystal oscillator, after the clock signals of the movable platform 20 and the control terminal 30 are synchronized for the first time, The control terminal 30 also needs to use the second pulse sent by its own satellite positioning module 32 to re-determine the time offset, and the clock signal of the control terminal 30 can be recalibrated according to the re-determined time offset. For the specific implementation process, please refer to the above-mentioned preliminary calibration process of the clock signal of the control terminal 30, which will not be repeated here.

In the embodiment shown in FIG. 5, the control terminal 30 is not equipped with the satellite positioning module 32. Based on the drift characteristics of the crystal oscillator, after the clock signals of the movable platform 20 and the control terminal 30 are synchronized for the first time, The movable platform 20 needs to re-send the reference signal to the control terminal 30 according to the recalibrated clock signal after recalibrating its own clock signal; correspondingly, the control terminal 30 also repeats according to the re-sent reference signal The step of calibrating the clock signal of the control terminal 30. For the specific implementation process, please refer to the above-mentioned preliminary calibration process of the clock signal of the control terminal 30, which will not be repeated here.

It is understandable that this embodiment does not impose any restriction on when to recalibrate the clock signal, and specific settings can be made according to actual application scenarios. For example, the movable platform 20 or the control terminal 30 may periodically perform the step of recalibrating the clock signal.

In an embodiment, the movable platform 20 can establish a communication connection with a plurality of control terminals 30 at the same time, and interact with each other. In an example, the movable platform 20 is an unmanned aerial vehicle, and the control terminal 30 includes smart glasses and a remote controller, and the unmanned aerial vehicle can establish a communication connection with the smart glasses and the remote controller at the same time. Considering that when the movable platform 20 is connected to multiple control terminals 30, the multiple control terminals 30 are generally relatively close, so that the spectrum leakage interference between each other is large. In an example, please refer to Fig. 6, if no one The aircraft 20 is sending signals to the smart glasses 30. At this time, if the remote control 30 sends signals to the unmanned aerial vehicle 20, since the two control terminals 30 are relatively close, the signal sent by the unmanned aerial vehicle 20 is likely to be submerged in the signal sent by the remote control 30. Among the signals, the smart glasses 30 fail to receive the signals.

Based on this, in this embodiment, the control terminal 30 includes a first control terminal 30 and a second control terminal 30, and the movable platform 20 is established with the first control terminal 30 and the second control terminal 30. Communication connection, after synchronizing the clock signals of the movable platform 20, the first control terminal 30 and the second control terminal 30, the movable platform 20, the first control terminal 30 and the second control terminal 30 The clock signal is aligned with the satellite positioning system, that is, the time when the first control terminal 30 and the second control terminal 30 send and receive signals are aligned. In this way, the first control terminal 30 can be more accurately controlled when the signal is received during the period. , The second control terminal 30 is also in the period of receiving the signal, which can effectively alleviate the crosstalk problem to a certain extent.

In order to further ensure that the crosstalk problem does not occur between the movable platform 20, the first control terminal 30, and the second control terminal 30, the movable platform 20, the first control terminal 30, and the second control terminal are synchronized. After the clock signal of the terminal 30, the movable platform 20 transmits prompt information to the second control terminal 30 before transmitting the signal to the first control terminal 30; the prompt information is used to prompt the second control terminal 30 Terminal 30: During the period when the movable platform 20 transmits a signal to the first control terminal 30, no signal is transmitted to the movable platform 20, thereby further ensuring that the movable platform 20 and the first control terminal 30 The crosstalk problem does not occur between the second control terminal 30 and the second control terminal 30, and the correct signal receiving and sending process is ensured.

In addition, considering that the receiving capability of the movable platform 20 is limited, if the first control terminal 30 and the second control terminal 30 send signals to the movable platform 20 at the same time, the movable platform 20 may not be able to Two signals are received accurately at the same time, and because the two control terminals 30 are close together, the signals of the two interfere with each other, which may cause crosstalk problems. In one example, please refer to Figure 7, the smart glasses 30 and the remote control 30 give The UAV 20 sends signals, where the dotted line represents the signal sent by the smart glasses 30, and the solid line represents the signal sent by the remote control 30, and there is a crosstalk problem between the two signals.

Based on this, the first control terminal 30 and the second control terminal 30 also establish a communication connection, after synchronizing the clock signals of the movable platform 20, the first control terminal 30, and the second control terminal 30 In order to further ensure that crosstalk does not occur between the movable platform 20, the first control terminal 30, and the second control terminal 30, before the first control terminal 30 transmits a signal to the movable platform 20, Transmit prompt information to the second control terminal 30; the prompt information is used to prompt the second control terminal 30: During the period when the first control terminal 30 transmits a signal to the movable platform 20, not to the The movable platform 20 transmits signals, so as to ensure the correct transmission and reception of the signals.

Correspondingly, please refer to FIG. 8. An embodiment of the present application also provides a synchronization method, which is applied to a synchronization system. The synchronization system includes a movable platform and a control terminal. There is a communication connection, the mobile platform is equipped with a communication module and a satellite positioning module, and the method includes:

In step S101, the communication module of the movable platform receives the second pulse sent by the satellite positioning module of the movable platform at a specified time interval, and records the arrival time of the second pulse; according to the arrival time of the second pulse And at the specified time interval, the clock signal of the movable platform is calibrated; based on the calibrated clock signal, a reference signal is sent to the control terminal.

In step S102, the control terminal calibrates the clock signal of the control terminal according to the reference signal, so as to synchronize the clock signal of the movable platform and the control terminal.

In an embodiment, the control terminal is equipped with a communication module and a satellite positioning module.

Before the control terminal calibrates the clock signal of the control terminal according to the reference signal, the method further includes: the communication module of the control terminal receives the second pulse sent by the satellite positioning module of the control terminal at the specified time interval , And record the arrival time of the second pulse; perform preliminary calibration on the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval.

In an embodiment, the calibrating the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval includes: according to the arrival time of the second pulse and the specified time Interval, determining the frequency offset and/or time offset of the clock signal of the movable platform; and calibrating the clock signal of the movable platform according to the frequency offset and/or time offset.

In an embodiment, the preliminary calibration of the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval includes: according to the arrival time of the second pulse and the specified time Interval, determining the frequency offset and/or time offset of the clock signal of the control terminal; and performing preliminary calibration on the clock signal of the movable platform according to the frequency offset and/or time offset.

In an embodiment, the frequency offset is determined based on the relative relationship between the time difference between the M second pulses arriving at the communication module and the time difference between the M second pulses being sent from the satellite positioning module; M Is an integer; wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.

In an embodiment, the time offset is the result of a remainder operation performed between the time when the second pulse arrives at the communication module and the specified time interval.

In an embodiment, the reference signal includes N reference signals sent periodically; N is an integer.

The calibrating the clock signal of the control terminal according to the reference signal includes: according to the time difference between the time difference between sending the N reference signals by the movable platform and the time difference between receiving the N reference signals by the control terminal The clock signal of the control terminal is calibrated.

In an embodiment, the control terminal is further configured to send a response signal to the movable platform according to the reference signal.

The calibrating the clock signal of the control terminal according to the reference signal includes: determining the movable platform and the mobile platform according to the sending time and receiving time of the reference signal and the sending time and receiving time of the response signal The time deviation between the control terminals is used to calibrate the clock signal of the control terminal.

In an embodiment, the reference signal includes pilot symbols.

The calibrating the clock signal of the control terminal according to the reference signal includes: acquiring a first frequency domain received signal and a second frequency domain received signal corresponding to two adjacent reference signals in the time domain; A frequency domain received signal and the pilot symbol obtain a first frequency domain channel value, and a second frequency domain channel value is obtained according to the second frequency domain received signal and the pilot symbol; and the first frequency domain channel Transform the value in the time domain to obtain the first time-domain channel impulse response, and perform the time-domain transformation of the second frequency-domain channel value to obtain the second time-domain channel impulse response; according to the first time-domain channel impulse response and Determining the energy value of the second time domain channel impulse response, determining the first target response data of the first time domain channel impulse response, and the second target response data of the second time domain channel impulse response; The clock signal of the control terminal is calibrated according to the first target response data and the second target response data.

In an embodiment, the control terminal includes a first control terminal and a second control terminal.

After synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the method further includes: before the movable platform transmits a signal to the first control terminal, sending a signal to the second control terminal The terminal transmits prompt information; the prompt information is used to prompt the second control terminal: during the period when the movable platform transmits a signal to the first control terminal, no signal is transmitted to the movable platform.

In an embodiment, the first control terminal establishes a communication connection with the second control terminal.

After synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the method further includes: before the first control terminal transmits the signal to the movable platform, the second control terminal The terminal transmits prompt information; the prompt information is used to prompt the second control terminal: during the period when the first control terminal transmits a signal to the movable platform, no signal is transmitted to the movable platform.

In an embodiment, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the method further includes: the communication module of the movable platform recalibrates the movable platform based on the re-determined time offset. Clock signal, and re-send a reference signal to the control terminal according to the recalibrated clock signal; the control terminal repeats the step of calibrating the clock signal of the control terminal according to the re-sent reference signal.

In an embodiment, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the method further includes: the communication module of the movable platform recalibrates the movable platform based on the re-determined time offset. The clock signal of the mobile platform; and, the communication module of the control terminal recalibrates the clock signal of the control terminal according to the re-determined time offset.

For the specific implementation process of the synchronization method, please refer to the description of the relevant parts in the synchronization system, which will not be repeated here.

Correspondingly, please refer to FIG. 9. This embodiment also provides a movable platform 20, including:

Body 24.

The power system 23 is arranged inside the fuselage and provides power for the movable platform.

The satellite positioning module 22 is arranged inside the fuselage and is used to send a second pulse to the communication module 21 at a specified time interval.

The communication module 21 is arranged inside the body and is used to perform the following steps: receiving the second pulse and recording the arrival time of the second pulse; according to the arrival time of the second pulse and the specified time interval , The clock signal of the movable platform is calibrated; based on the calibrated clock signal, a reference signal is sent to the control terminal of the movable platform, and the reference signal is used to synchronize the movable platform and the control terminal Clock signal.

In an embodiment, when calibrating the clock signal of the movable platform 20, the communication module 21 of the movable platform 20 is specifically configured to: according to the arrival time of the second pulse and the specified time interval, The frequency offset and/or time offset of the clock signal of the movable platform 20 are determined; the clock signal of the movable platform 20 is calibrated according to the frequency offset and/or time offset.

In an embodiment, the frequency offset is determined based on the relative relationship between the time difference between the M second pulses arriving at the communication module 21 and the time difference between the M second pulses being sent from the satellite positioning module; M is an integer; wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.

In an embodiment, the time offset is the result of the remainder operation between the time when the second pulse arrives at the communication module 21 and the specified time interval.

After synchronizing the clock signals of the movable platform 20, the first control terminal, and the second control terminal, the communication module 21 of the movable platform 20 is further configured to: before transmitting a signal to the first control terminal , Transmit prompt information to the second control terminal; the prompt information is used to prompt the second control terminal: during the period when the movable platform 20 transmits a signal to the first control terminal, not to the movable The platform 20 transmits a signal.

In an embodiment, after synchronizing the clock signals of the movable platform 20 and the control terminal for the first time, the communication module 21 of the movable platform 20 is further configured to: recalibrate the mobile platform based on the re-determined time offset. The clock signal of the movable platform 20 is movable, and the reference signal is re-sent to the control terminal according to the recalibrated clock signal.

For the specific implementation process of the movable platform, please refer to the description of the relevant parts in the above synchronization system, which will not be repeated here.

Correspondingly, referring to FIG. 10, this embodiment also provides a synchronization method, which is applied to a movable platform, and a communication connection is established between the movable platform and the control terminal, and the method includes:

In step S201, the second pulse sent by the satellite positioning module of the movable platform at a specified time interval is received, and the arrival time of the second pulse is recorded.

In step S202, the clock signal of the movable platform is calibrated according to the arrival time of the second pulse and the specified time interval.

In step S203, a reference signal is sent to the control terminal based on the calibrated clock signal; the reference signal is used to synchronize the clock signal of the movable platform and the control terminal.

After synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the method further includes: transmitting prompt information to the second control terminal before transmitting the signal to the first control terminal; The prompt information is used to prompt the second control terminal: during the period when the movable platform transmits a signal to the first control terminal, no signal is transmitted to the movable platform.

In an embodiment, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the method further includes: recalibrating the clock signal of the movable platform based on the re-determined time offset, and according to the recalibrated clock signal. The clock signal of is re-sends the reference signal to the control terminal.

Correspondingly, please refer to FIG. 11, an embodiment of the present application also provides a control terminal 30, including a satellite synchronization module and a communication module 31.

The satellite positioning module 32 is configured to send a second pulse to the communication module 31 at a specified time interval.

The communication module 31 is configured to: receive the second pulse, and record the arrival time of the second pulse; according to the arrival time of the second pulse and the specified time interval, perform a preliminary analysis of the clock signal of the control terminal 30 Calibration; According to the reference signal received from the movable platform, the pre-calibrated clock signal is further calibrated to synchronize the clock signal of the movable platform and the control terminal 30.

In one embodiment, when performing preliminary calibration on the clock signal of the control terminal 30, the communication module 31 of the control terminal 30 is specifically configured to: determine according to the arrival time of the second pulse and the specified time interval The frequency offset and/or time offset of the clock signal of the control terminal 30; the clock signal of the movable platform is preliminarily calibrated according to the frequency offset and/or time offset.

In an embodiment, the frequency offset is determined based on the relative relationship between the time difference between the M second pulses arriving at the communication module 31 and the time difference between the M second pulses being sent from the satellite positioning module 32 ; M is an integer; wherein, the time difference between the M second pulses sent from the satellite positioning module 32 is determined based on the specified time interval.

In an embodiment, the time offset is the result of the remainder operation between the time when the second pulse reaches the communication module 31 and the specified time interval.

When the clock signal of the control terminal 30 is further calibrated according to the reference signal, the communication module 31 is specifically configured to: according to the time difference between the N reference signals sent by the movable platform and the control terminal 30 The difference between the time differences of the N reference signals is received, and the clock signal of the control terminal 30 is calibrated.

In an embodiment, the control terminal 30 is further configured to send a response signal to the movable platform according to the reference signal.

When the clock signal of the control terminal 30 is further calibrated according to the reference signal, the communication module 31 is specifically configured to: according to the sending time and receiving time of the reference signal, and the sending time and the response signal The receiving time determines the time deviation between the movable platform and the control terminal 30 to calibrate the clock signal of the control terminal 30.

In an embodiment, the reference signal includes pilot symbols; when the clock signal of the control terminal 30 is further calibrated according to the reference signal, the communication module 31 is specifically configured to: obtain time-domain neighbors The first frequency domain received signal and the second frequency domain received signal corresponding to the two reference signals; the first frequency domain channel value is obtained according to the first frequency domain received signal and the pilot symbol, and the first frequency domain channel value is obtained according to the second frequency domain. Domain received signal and the pilot symbol to obtain a second frequency domain channel value; time domain transform is performed on the first frequency domain channel value to obtain a first time domain channel impulse response, and the second frequency domain channel value is Time domain transformation is used to obtain a second time domain channel impulse response; the first time domain channel impulse response is determined according to the energy value of the first time domain channel impulse response and the second time domain channel impulse response The first target response data of the first target response data, and the second target response data of the second time domain channel impulse response; the clock signal of the control terminal 30 according to the first target response data and the second target response data Perform calibration.

In an embodiment, the control terminal 30 includes a first control terminal 30 and a second control terminal 30; the first control terminal 30 and the second control terminal 30 establish a communication connection.

After synchronizing the clock signals of the movable platform, the first control terminal 30, and the second control terminal 30, the first control terminal 30 is further configured to: before transmitting a signal to the movable platform, The second control terminal 30 transmits prompt information; the prompt information is used to prompt the second control terminal 30: During the period when the first control terminal 30 transmits a signal to the movable platform, not to the movable platform transmit a signal.

In an embodiment, after synchronizing the clock signals of the movable platform and the control terminal 30 for the first time, the communication module 31 of the control terminal 30 is further configured to: recalibrate the control according to the re-determined time offset The clock signal of the terminal 30; or, the step of calibrating the clock signal of the control terminal 30 is repeated according to the re-sent reference signal.

For the specific implementation process of the control terminal, please refer to the description of the relevant parts in the above synchronization system, which will not be repeated here.

Correspondingly, referring to FIG. 12, this embodiment also provides a synchronization method, which is applied to a control terminal, and a communication connection is established between the control terminal and a movable platform, and the method includes:

In step S301, the second pulse sent by the satellite positioning module of the control terminal at a specified time interval is received, and the arrival time of the second pulse is recorded.

In step S302, the clock signal of the control terminal is preliminarily calibrated according to the arrival time of the second pulse and the specified time interval.

In step S303, the pre-calibrated clock signal is further calibrated according to the reference signal received from the movable platform to synchronize the clock signal of the movable platform and the control terminal.

The further calibration of the pre-calibrated clock signal according to the reference signal received from the movable platform includes: according to the time difference between sending the N reference signals by the movable platform and receiving the N reference signals by the control terminal The difference between the time difference of the signal, the clock signal of the control terminal is calibrated.

The further calibration of the preliminarily calibrated clock signal according to the reference signal received from the movable platform includes: determining the clock signal according to the sending time and receiving time of the reference signal, and the sending time and receiving time of the response signal. The time deviation between the movable platform and the control terminal is used to calibrate the clock signal of the control terminal.

In an embodiment, the reference signal includes pilot symbols.

The further calibration of the pre-calibrated clock signal according to the reference signal received from the movable platform includes: obtaining a first frequency domain received signal and a second frequency domain received signal corresponding to two adjacent reference signals in the time domain Obtain a first frequency domain channel value according to the first frequency domain received signal and the pilot symbol, and obtain a second frequency domain channel value according to the second frequency domain received signal and the pilot symbol; The first frequency domain channel value is time-domain transformed to obtain a first time-domain channel impulse response, and the second frequency-domain channel value is time-domain transformed to obtain a second time-domain channel impulse response; Channel impulse response and the energy value of the second time domain channel impulse response, determine the first target response data of the first time domain channel impulse response, and the first target response data of the second time domain channel impulse response 2. Target response data; calibrate the clock signal of the control terminal according to the first target response data and the second target response data.

In an embodiment, the control terminal includes a first control terminal and a second control terminal; the first control terminal establishes a communication connection with the second control terminal.

When the synchronization method is applied to the first control terminal, after synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the method further includes: Before transmitting the signal, transmit prompt information to the second control terminal; the prompt information is used to prompt the second control terminal: during the period when the first control terminal transmits a signal to the movable platform, not to the The movable platform transmits signals.

In an embodiment, after synchronizing the clock signal of the movable platform and the control terminal for the first time, the method further includes: recalibrating the clock signal of the control terminal according to the re-determined time offset; or, according to the re-sent The reference signal repeats the steps of calibrating the clock signal of the control terminal.

It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply one of these entities or operations. There is any such actual relationship or order between. The terms "include", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements that are not explicitly listed. Elements, or also include elements inherent to such processes, methods, articles, or equipment. If there are no more restrictions, the element defined by the sentence "including a..." does not exclude the existence of other identical elements in the process, method, article, or equipment that includes the element.

The methods and devices provided by the embodiments of the application are described in detail above. Specific examples are used in this article to illustrate the principles and implementations of the application. The descriptions of the above embodiments are only used to help understand the methods and methods of the application. Core idea; At the same time, for those of ordinary skill in the art, according to the idea of this application, there will be changes in the specific implementation and scope of application. In summary, the content of this specification should not be construed as a limitation to this application .

Claims

A synchronization system, characterized in that it comprises a movable platform and a control terminal, and a communication connection is established between the movable platform and the control terminal;

The mobile platform is equipped with a communication module and a satellite positioning module;

The communication module of the movable platform is used to: receive the second pulse sent by the satellite positioning module of the movable platform at a specified time interval, and record the arrival time of the second pulse; according to the arrival time and the time of the second pulse Calibrate the clock signal of the movable platform at the specified time interval; send a reference signal to the control terminal based on the calibrated clock signal;

The control terminal is used to calibrate the clock signal of the control terminal according to the reference signal, so as to synchronize the clock signal of the movable platform and the control terminal.
The system according to claim 1, wherein the control terminal is equipped with a communication module and a satellite positioning module;

The communication module of the control terminal is used to: receive the second pulse sent by the satellite positioning module of the control terminal at the specified time interval, and record the arrival time of the second pulse; At the specified time interval, the clock signal of the control terminal is preliminarily calibrated; the pre-calibrated clock signal is further calibrated according to the reference signal to synchronize the clock signals of the movable platform and the control terminal.
The system according to claim 1, wherein when calibrating the clock signal of the movable platform, the communication module of the movable platform is specifically configured to: according to the arrival time of the second pulse and the Specify a time interval to determine the frequency offset and/or time offset of the clock signal of the movable platform; and calibrate the clock signal of the movable platform according to the frequency offset and/or time offset.
The system according to claim 2, wherein when performing preliminary calibration on the clock signal of the control terminal, the communication module of the control terminal is specifically configured to: according to the arrival time of the second pulse and the designated The time interval determines the frequency offset and/or time offset of the clock signal of the control terminal; and performs preliminary calibration on the clock signal of the movable platform according to the frequency offset and/or time offset.
The system according to claim 3 or 4, wherein the frequency offset is based on the time difference between the M second pulses arriving at the communication module and the M second pulses being sent from the satellite positioning module Is determined by the relative relationship of the time difference; M is an integer;

Wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.
The system according to claim 3 or 4, wherein the time offset is the result of a remainder calculation between the time when the second pulse arrives at the communication module and the specified time interval.
The system according to claim 1, wherein the reference signal comprises N reference signals sent periodically; N is an integer;

When the clock signal of the control terminal is calibrated according to the reference signal, the control terminal is specifically configured to: according to the time difference between sending the N reference signals by the movable platform and receiving the N reference signals by the control terminal The clock signal of the control terminal is calibrated based on the difference between the time difference of the reference signal.
The system according to claim 1, wherein the control terminal is further configured to send a response signal to the movable platform according to the reference signal;

When the clock signal of the control terminal is calibrated according to the reference signal, the control terminal is specifically configured to: determine according to the sending time and receiving time of the reference signal and the sending time and receiving time of the response signal The time deviation between the movable platform and the control terminal is used to calibrate the clock signal of the control terminal.
The system according to claim 1, wherein the reference signal includes pilot symbols, and when the clock signal of the control terminal is calibrated according to the reference signal, the control terminal is specifically configured to:

Acquiring a first frequency domain received signal and a second frequency domain received signal corresponding to two adjacent reference signals in the time domain;

Obtaining a first frequency domain channel value according to the first frequency domain received signal and the pilot symbol, and obtaining a second frequency domain channel value according to the second frequency domain received signal and the pilot symbol;

Time-domain transforming the first frequency-domain channel value to obtain a first time-domain channel impulse response, and time-domain transforming the second frequency-domain channel value to obtain a second time-domain channel impulse response;

According to the energy values of the first time domain channel impulse response and the second time domain channel impulse response, the first target response data of the first time domain channel impulse response and the second time domain are determined Second target response data of the domain channel impulse response;

The clock signal of the control terminal is calibrated according to the first target response data and the second target response data.
The system according to claim 1, wherein the control terminal comprises a first control terminal and a second control terminal;

After synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the movable platform is further configured to: before transmitting a signal to the first control terminal, to the second control terminal The control terminal transmits prompt information; the prompt information is used to prompt the second control terminal: during the period when the movable platform transmits a signal to the first control terminal, no signal is transmitted to the movable platform.
The system according to claim 10, wherein the first control terminal establishes a communication connection with the second control terminal;

After synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the first control terminal is further configured to: before transmitting the signal to the movable platform, to the second The control terminal transmits prompt information; the prompt information is used to prompt the second control terminal: during the period when the first control terminal transmits a signal to the movable platform, no signal is transmitted to the movable platform.
The system according to claim 3, characterized in that, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the communication module of the movable platform is further configured to: based on the re-determined time offset Recalibrate the clock signal of the movable platform, and resend the reference signal to the control terminal according to the recalibrated clock signal;

The control terminal is further configured to: repeat the step of calibrating the clock signal of the control terminal according to the retransmitted reference signal.
The system according to claim 4, wherein after synchronizing the clock signals of the movable platform and the control terminal for the first time, the communication module of the movable platform is further configured to: based on a re-determined time offset Recalibrate the clock signal of the movable platform; and,

The communication module of the control terminal is further configured to: recalibrate the clock signal of the control terminal according to the re-determined time offset.
The system according to claim 1 or 2, wherein the satellite positioning module comprises a GNSS module.
The system according to claim 1, wherein the movable platform includes at least any one of the following: an unmanned aerial vehicle, an unmanned vehicle, an unmanned boat, or a mobile robot.
A synchronization method, characterized in that it is applied to a synchronization system, the synchronization system includes a movable platform and a control terminal, a communication connection is established between the movable platform and the control terminal, and the movable platform is installed with A communication module and a satellite positioning module, the method includes:

The communication module of the movable platform receives the second pulse sent by the satellite positioning module of the movable platform at a specified time interval, and records the arrival time of the second pulse; according to the arrival time of the second pulse and the specified time Interval, calibrate the clock signal of the movable platform; send a reference signal to the control terminal based on the calibrated clock signal;

The control terminal calibrates the clock signal of the control terminal according to the reference signal to synchronize the clock signal of the movable platform and the control terminal.
The method according to claim 16, wherein the control terminal is equipped with a communication module and a satellite positioning module;

Before the control terminal calibrates the clock signal of the control terminal according to the reference signal, the method further includes: the communication module of the control terminal receives the second pulse sent by the satellite positioning module of the control terminal at the specified time interval , And record the arrival time of the second pulse;

Perform preliminary calibration on the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval.
The method according to claim 16, wherein the calibrating the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval comprises:

Determine the frequency offset and/or time offset of the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval;

The clock signal of the movable platform is calibrated according to the frequency offset and/or time offset.
The method according to claim 17, wherein the preliminary calibration of the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval comprises:

Determining the frequency offset and/or time offset of the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval;

Preliminary calibration is performed on the clock signal of the movable platform according to the frequency offset and/or the time offset.
The method according to claim 18 or 19, wherein the frequency offset is based on the time difference between the M second pulses arriving at the communication module and the M second pulses being sent from the satellite positioning module Is determined by the relative relationship of the time difference; M is an integer;

Wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.
The method according to claim 18 or 19, wherein the time offset is the result of a remainder operation between the time when the second pulse arrives at the communication module and the specified time interval.
The method according to claim 16, wherein the reference signal comprises N reference signals sent periodically; N is an integer;

The calibrating the clock signal of the control terminal according to the reference signal includes:

The clock signal of the control terminal is calibrated according to the difference between the time difference between when the movable platform sends the N reference signals and the time difference between when the control terminal receives the N reference signals.
The method according to claim 16, wherein the control terminal is further configured to send a response signal to the movable platform according to the reference signal;

The calibrating the clock signal of the control terminal according to the reference signal includes:

The time deviation between the movable platform and the control terminal is determined according to the transmission time and reception time of the reference signal, and the transmission time and reception time of the response signal, so as to perform a check on the clock signal of the control terminal. calibration.
The method according to claim 16, wherein the reference signal includes pilot symbols;

The calibrating the clock signal of the control terminal according to the reference signal includes:

Acquiring a first frequency domain received signal and a second frequency domain received signal corresponding to two adjacent reference signals in the time domain;

Obtaining a first frequency domain channel value according to the first frequency domain received signal and the pilot symbol, and obtaining a second frequency domain channel value according to the second frequency domain received signal and the pilot symbol;

Time-domain transforming the first frequency-domain channel value to obtain a first time-domain channel impulse response, and time-domain transforming the second frequency-domain channel value to obtain a second time-domain channel impulse response;

According to the energy values of the first time domain channel impulse response and the second time domain channel impulse response, the first target response data of the first time domain channel impulse response and the second time domain are determined Second target response data of the domain channel impulse response;

The clock signal of the control terminal is calibrated according to the first target response data and the second target response data.
The method according to claim 16, wherein the control terminal comprises a first control terminal and a second control terminal;

After synchronizing the clock signals of the movable platform, the first control terminal and the second control terminal, the method further includes:

Before the mobile platform transmits a signal to the first control terminal, it transmits prompt information to the second control terminal; the prompt information is used to prompt the second control terminal: During the signal transmission period of the first control terminal, no signal is transmitted to the movable platform.
The method according to claim 25, wherein the first control terminal establishes a communication connection with the second control terminal;

After synchronizing the clock signals of the movable platform, the first control terminal and the second control terminal, the method further includes:

Before transmitting a signal to the movable platform, the first control terminal transmits prompt information to the second control terminal; the prompt information is used to prompt the second control terminal: During the signal transmission period of the movable platform, no signal is transmitted to the movable platform.
The method according to claim 18, characterized in that, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the method further comprises:

The communication module of the movable platform recalibrates the clock signal of the movable platform based on the re-determined time offset, and resends the reference signal to the control terminal according to the recalibrated clock signal;

The control terminal repeats the step of calibrating the clock signal of the control terminal according to the re-sent reference signal.
The method according to claim 19, characterized in that, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the method further comprises:

The communication module of the movable platform recalibrates the clock signal of the movable platform based on the re-determined time offset; and,

The communication module of the control terminal recalibrates the clock signal of the control terminal according to the re-determined time offset.
A movable platform, characterized in that it comprises:

body;

The power system is located inside the fuselage and provides power for the movable platform;

The satellite positioning module is arranged inside the fuselage and is used to send a second pulse to the communication module at a specified time interval;

The communication module is arranged inside the fuselage and is used to perform the following steps:

Receiving the second pulse, and recording the arrival time of the second pulse;

Calibrate the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval;

Based on the calibrated clock signal, a reference signal is sent to the control terminal of the movable platform, and the reference signal is used to synchronize the clock signal of the movable platform and the control terminal.
The movable platform according to claim 29, wherein when calibrating the clock signal of the movable platform, the communication module of the movable platform is specifically configured to: according to the arrival time of the second pulse and The specified time interval determines the frequency offset and/or time offset of the clock signal of the movable platform; and calibrates the clock signal of the movable platform according to the frequency offset and/or time offset.
The mobile platform of claim 30, wherein the frequency offset is based on the time difference between the M second pulses arriving at the communication module and the M second pulses being sent from the satellite positioning module Is determined by the relative relationship of the time difference; M is an integer;

Wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.
The movable platform according to claim 30, wherein the time offset is the result of a remainder operation between the time when the second pulse arrives at the communication module and the specified time interval.
The mobile platform according to claim 29, wherein the control terminal comprises a first control terminal and a second control terminal;

After synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the communication module of the movable platform is further configured to: before transmitting a signal to the first control terminal, The second control terminal transmits prompt information; the prompt information is used to prompt the second control terminal: during the period when the movable platform transmits a signal to the first control terminal, no signal is transmitted to the movable platform.
The movable platform according to claim 30, wherein after the clock signals of the movable platform and the control terminal are synchronized for the first time, the communication module of the movable platform is further configured to: based on the re-determined time Offset recalibrates the clock signal of the movable platform, and resends the reference signal to the control terminal according to the recalibrated clock signal.
A synchronization method, characterized in that it is applied to a movable platform, and a communication connection is established between the movable platform and a control terminal, and the method includes:

Receiving the second pulse sent by the satellite positioning module of the mobile platform at a specified time interval, and recording the arrival time of the second pulse;

Calibrate the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval;

Based on the calibrated clock signal, a reference signal is sent to the control terminal; the reference signal is used to synchronize the clock signal of the movable platform and the control terminal.
The method according to claim 35, wherein the calibrating the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval comprises:

Determine the frequency offset and/or time offset of the clock signal of the movable platform according to the arrival time of the second pulse and the specified time interval;

The clock signal of the movable platform is calibrated according to the frequency offset and/or time offset.
The method according to claim 36, wherein the frequency offset is based on the time difference between the time when the M second pulses arrive at the communication module and the time when the M second pulses are sent from the satellite positioning module Is determined by the relative relationship; M is an integer;

Wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.
The method according to claim 36, wherein the time offset is the result of a remainder operation performed between the time when the second pulse arrives at the communication module and the specified time interval.
The method according to claim 35, wherein the control terminal comprises a first control terminal and a second control terminal;

After synchronizing the clock signals of the movable platform, the first control terminal and the second control terminal, the method further includes:

Before transmitting a signal to the first control terminal, transmit prompt information to the second control terminal; the prompt information is used to prompt the second control terminal: to the first control terminal on the movable platform During the signal transmission period, no signal is transmitted to the movable platform.
The method according to claim 36, characterized in that, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the method further comprises:

Recalibrate the clock signal of the movable platform based on the re-determined time offset, and resend the reference signal to the control terminal according to the recalibrated clock signal.
A control terminal, characterized in that it comprises a satellite synchronization module and a communication module;

The satellite positioning module is configured to: send a second pulse to the communication module at a specified time interval;

The communication module is used for:

Receiving the second pulse, and recording the arrival time of the second pulse;

Perform preliminary calibration on the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval;

The pre-calibrated clock signal is further calibrated according to the reference signal received from the movable platform to synchronize the clock signal of the movable platform and the control terminal.
The control terminal according to claim 41, wherein when performing preliminary calibration of the clock signal of the control terminal, the communication module of the control terminal is specifically configured to: according to the arrival time of the second pulse and the Specify a time interval to determine the frequency offset and/or time offset of the clock signal of the control terminal; perform preliminary calibration on the clock signal of the movable platform according to the frequency offset and/or time offset.
The control terminal according to claim 42, wherein the frequency offset is based on the time difference between the M number of second pulses arriving at the communication module and the time difference between the M number of second pulses being sent from the satellite positioning module Determined by the relative relationship of the time difference; M is an integer;

Wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.
The control terminal according to claim 42, wherein the time offset is the result of a remainder operation between the time when the second pulse arrives at the communication module and the specified time interval.
The control terminal according to claim 41, wherein the reference signal comprises N reference signals sent periodically; N is an integer;

When the clock signal of the control terminal is further calibrated according to the reference signal, the communication module is specifically configured to: according to the time difference between sending the N reference signals by the movable platform and receiving the N reference signals by the control terminal The difference between the time differences of the two reference signals is used to calibrate the clock signal of the control terminal.
The control terminal according to claim 41, wherein the control terminal is further configured to send a response signal to the movable platform according to the reference signal;

When the clock signal of the control terminal is further calibrated according to the reference signal, the communication module is specifically configured to: according to the sending time and receiving time of the reference signal, and the sending time and receiving time of the response signal The time deviation between the movable platform and the control terminal is determined to calibrate the clock signal of the control terminal.
The control terminal according to claim 41, wherein the reference signal includes pilot symbols; when the clock signal of the control terminal is further calibrated according to the reference signal, the communication module is specifically configured to :

Acquiring a first frequency domain received signal and a second frequency domain received signal corresponding to two adjacent reference signals in the time domain;

Obtaining a first frequency domain channel value according to the first frequency domain received signal and the pilot symbol, and obtaining a second frequency domain channel value according to the second frequency domain received signal and the pilot symbol;

Time-domain transforming the first frequency-domain channel value to obtain a first time-domain channel impulse response, and time-domain transforming the second frequency-domain channel value to obtain a second time-domain channel impulse response;

According to the energy values of the first time domain channel impulse response and the second time domain channel impulse response, the first target response data of the first time domain channel impulse response and the second time domain are determined Second target response data of the domain channel impulse response;

The clock signal of the control terminal is calibrated according to the first target response data and the second target response data.
The control terminal according to claim 41, wherein the control terminal comprises a first control terminal and a second control terminal; the first control terminal and the second control terminal establish a communication connection;

After synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the first control terminal is further configured to: before transmitting the signal to the movable platform, to the second The control terminal transmits prompt information; the prompt information is used to prompt the second control terminal: during the period when the first control terminal transmits a signal to the movable platform, no signal is transmitted to the movable platform.
The control terminal according to claim 42, characterized in that, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the communication module of the control terminal is further configured to: according to the re-determined time offset Recalibrate the clock signal of the control terminal; or, repeat the step of calibrating the clock signal of the control terminal according to the re-sent reference signal.
A synchronization method, characterized in that it is applied to a control terminal, and a communication connection is established between the control terminal and a movable platform, and the method includes:

Receiving the second pulse sent by the satellite positioning module of the control terminal at a specified time interval, and recording the arrival time of the second pulse;

Perform preliminary calibration on the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval;

The pre-calibrated clock signal is further calibrated according to the reference signal received from the movable platform to synchronize the clock signal of the movable platform and the control terminal.
The method according to claim 50, wherein the preliminary calibration of the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval comprises:

Determine the frequency offset and/or time offset of the clock signal of the control terminal according to the arrival time of the second pulse and the specified time interval; Perform preliminary calibration on the clock signal of the mobile platform.
The method of claim 51, wherein the frequency offset is based on the time difference between the M second pulses arriving at the communication module and the time difference between the M second pulses being sent from the satellite positioning module Is determined by the relative relationship; M is an integer;

Wherein, the time difference between the M second pulses sent from the satellite positioning module is determined based on the specified time interval.
The method according to claim 51, wherein the time offset is the result of a remainder operation performed between the time when the second pulse arrives at the communication module and the specified time interval.
The method according to claim 50, wherein the reference signal comprises N reference signals sent periodically; N is an integer;

The further calibration of the clock signal after preliminary calibration according to the reference signal received from the movable platform includes:

The clock signal of the control terminal is calibrated according to the difference between the time difference between the N reference signals sent by the movable platform and the time difference between the N reference signals received by the control terminal.
The method according to claim 50, wherein the control terminal is further configured to send a response signal to the movable platform according to the reference signal;

The further calibration of the clock signal after preliminary calibration according to the reference signal received from the movable platform includes:

The time deviation between the movable platform and the control terminal is determined according to the transmission time and reception time of the reference signal, and the transmission time and reception time of the response signal, so as to perform a check on the clock signal of the control terminal. calibration.
The method of claim 50, wherein the reference signal includes pilot symbols;

The further calibration of the clock signal after preliminary calibration according to the reference signal received from the movable platform includes:

Acquiring a first frequency domain received signal and a second frequency domain received signal corresponding to two adjacent reference signals in the time domain;

Obtaining a first frequency domain channel value according to the first frequency domain received signal and the pilot symbol, and obtaining a second frequency domain channel value according to the second frequency domain received signal and the pilot symbol;

Time-domain transforming the first frequency-domain channel value to obtain a first time-domain channel impulse response, and time-domain transforming the second frequency-domain channel value to obtain a second time-domain channel impulse response;

According to the energy values of the first time domain channel impulse response and the second time domain channel impulse response, the first target response data of the first time domain channel impulse response and the second time domain are determined Second target response data of the domain channel impulse response;

The clock signal of the control terminal is calibrated according to the first target response data and the second target response data.
The method according to claim 50, wherein the control terminal comprises a first control terminal and a second control terminal; the first control terminal and the second control terminal establish a communication connection;

When the synchronization method is applied to the first control terminal, after synchronizing the clock signals of the movable platform, the first control terminal, and the second control terminal, the method further includes:

Before transmitting a signal to the movable platform, transmit prompt information to the second control terminal; the prompt information is used to prompt the second control terminal: the first control terminal transmits to the movable platform During the signal period, no signal is transmitted to the movable platform.
The method according to claim 51, characterized in that, after synchronizing the clock signals of the movable platform and the control terminal for the first time, the method further comprises:

The clock signal of the control terminal is recalibrated according to the re-determined time offset; or, the step of calibrating the clock signal of the control terminal is repeated according to the re-sent reference signal.