Wireless signal receiving device and wireless signal receiving method

Abstract

The invention provides a wireless signal receiving device and a wireless signal receiving method. The wireless signal receiving method is executed through the wireless signal receiving device and comprises the following steps: receiving a pilot signal and speed of an unmanned aerial vehicle through an antenna; executing a ground signal down-link receiving and synchronization algorithm, the ground signal down-link receiving and synchronization algorithm comprising the following steps: calculating a signal arrival angle according to the position of the unmanned aerial vehicle, the position of the antenna and the transmission direction of the pilot signal; according to the frequency, the speed and the signal arrival angle of the pilot signal, calculating a Meper frequency offset; adjusting the frequency of the pilot signal according to the Meper frequency offset; according to a preset time interval corresponding to the pilot signal, adjusting an occurrence time point of the pilot signal at the data symbol; and adjusting the sampling time point of the data symbol according to the occurrence time point. By means of the method, the Meper frequency offset is corrected, and signal frame synchronization is achieved.

Description

Technical Field

[0001] The present application relates to the field of communications, and in particular to a wireless signal receiving device and a wireless signal receiving method. Background Art

[0002] The orthogonal frequency division multiplexing (OFDM) system is a communication system for high-speed data transmission, and has better stability in the face of multipath interference and narrowband interference. However, the OFDM system is very sensitive to frequency shift and timing shift; the frequency shift is mainly caused by the Doppler effect, and the timing shift is due to the influence of noise and multipath interference, which makes it impossible to find the boundary of each symbol, resulting in inter-carrier interference.

[0003] The existing communication between drones and base stations on the ground is achieved through the OFDM system for two-way data transmission. However, because the drone moves relative to the base station, the Doppler frequency offset increases; when the Doppler frequency offset increases and the adjacent frequency has a beam carrying a large amount of data, it will cause quite serious in-band interference. Summary of the invention

[0004] The present application provides a wireless signal receiving device and a wireless signal receiving method to solve the problems of frequency offset and timing offset.

[0005] Based on the foregoing, the present application provides a wireless signal receiving device, which is arranged on the ground and communicates with a drone, and includes an antenna and a processor. The antenna receives the pilot signal and speed of the drone. The processor is electrically connected to the antenna and executes a ground signal downlink reception and synchronization algorithm, which includes the following steps: calculating the signal arrival angle according to the position of the drone, the position of the antenna, and the transmission direction of the pilot signal; calculating the Doppler frequency offset according to the frequency, speed, and signal arrival angle of the pilot signal; adjusting the frequency of the pilot signal according to the Doppler frequency offset; adjusting the appearance time point of the pilot signal in the data symbol according to the preset time interval of the corresponding pilot signal; adjusting the sampling time point of the data symbol according to the appearance time point.

[0006] Based on the above, the present application provides a wireless signal receiving method for a wireless signal receiving device including an antenna and a processor, wherein the wireless signal receiving device is disposed on the ground and communicates with a drone through the antenna. The wireless signal receiving method is executed through the processor and includes: receiving the pilot signal and speed of the drone through the antenna; executing a ground signal downlink receiving and synchronization algorithm, wherein the ground signal downlink receiving and synchronization algorithm includes the following steps: calculating the signal arrival angle according to the position of the drone, the position of the antenna, and the transmission direction of the pilot signal; calculating the Doppler frequency shift according to the frequency, speed, and signal arrival angle of the pilot signal; adjusting the frequency of the pilot signal according to the Doppler frequency shift; adjusting the appearance time point of the pilot signal in the data symbol according to the preset time point corresponding to the pilot signal; and adjusting the sampling time point of the data symbol according to the appearance time point.

[0007] In summary, the wireless signal receiving device and the wireless signal receiving method of the present application correct the Doppler frequency offset and solve the signal frame synchronization problem by adjusting the frequency of the pilot signal and the sampling time point of the data symbol.

[0008] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application and implement it according to the contents of the specification, the present application is described in detail below with reference to the preferred embodiments of the present application and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a configuration diagram of the signal frame.

[0010] Figure 2A The figure is a schematic diagram of a wireless signal receiving device and a drone according to an embodiment of the present application.

[0011] Figure 2B The figure is a configuration diagram of a wireless signal receiving device according to an embodiment of the present application.

[0012] Figure 3 The following is a flow chart of a wireless signal receiving method according to an embodiment of the present application.

[0013] Figure 4 A flow chart of a terrestrial signal downlink reception and synchronization algorithm is shown according to an embodiment of the present application.

[0014] Figure 5 The following is a flow chart of a wireless signal receiving method according to another embodiment of the present application.

[0015] Figure 6 A flow chart is shown for determining whether frequency synchronization and signal synchronization are completed to receive a data packet from a drone according to another embodiment of the present application.

[0016] Description of reference numerals:

[0017] 1: Wireless signal receiving device

[0018] 2: Drones

[0019] 10: Antenna

[0020] 20: Processor

[0021] CP1, CP2, CP3, CP4: Cyclic prefix

[0022] D1, D2: data symbol

[0023] LT1: Long training symbol

[0024] ST1: Short training symbol

[0025] S1: Signal symbol

[0026] S10, S20, S21 to S25, S1A to S7A, S31 to S40: Steps DETAILED DESCRIPTION

[0027] The following is an explanation of the implementation of the present application by means of specific embodiments. People familiar with the technology can easily understand other advantages and effects of the present application from the contents disclosed in this specification.

[0028] It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments. In order to enable those skilled in the art to better understand the present application scheme, the technical scheme in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only embodiments of a part of the present application, not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in the field without making creative work should fall within the scope of protection of the present application.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] In wireless communication systems, data is divided into multiple signal frames, each of which is transmitted from the transmitter to the receiver in the form of a bitstream. The following section will introduce the configuration of the signal frame in detail. Figure 1 , which is a configuration diagram of the signal frame. Figure 1 As shown, in the IEEE 802.11a wireless local area network standard, a signal frame includes a long training symbol LT1, a short training symbol ST1, a signal symbol S1, data symbols D1, D2, and cyclic prefixes CP1, CP2, CP3, CP4. The long training symbol LT1, the short training symbol ST1, the signal symbol S1, and the data symbols D1 and D2 are all OFDM symbols.

[0031] The long training symbol LT1 and the short training symbol ST1 are the leading parts of the signal frame to adjust the timing, packet detection and channel estimation. The signal symbol S1 carries the transmission rate, modulation form and coding rate of the data and is transmitted through multiple orthogonal sub-carriers in the OFDM system. The data symbols D1 and D2 carry the data to be transmitted and are transmitted through multiple orthogonal sub-carriers in the OFDM system. In addition, the signal symbol S1 and the data symbols D1 and D2 have multiple pilot signals respectively. The multiple pilot signals provide demodulation phase references and are arranged between two adjacent OFDM symbols of the signal symbol S1, between two adjacent OFDM symbols of the data symbol D1 and between two adjacent OFDM symbols of the data symbol D2. The multiple orthogonal sub-carriers carry multiple pilot signals. The multiple pilot signals are block-type and appear at specific time points of the signal symbol S1 and the data symbols D1 and D2. The time difference between two adjacent pilot signals is fixed.

[0032] The cyclic prefix CP1 is located between the long training symbol LT1 and the short training symbol ST1 to avoid symbol interference between the long training symbol LT1 and the short training symbol ST1; the cyclic prefix CP2 is located between the short training symbol ST1 and the signal symbol S1 to avoid symbol interference between the short training symbol ST1 and the signal symbol S1; the cyclic prefix CP3 is located between the signal symbol S1 and the data symbol D1 to avoid symbol interference between the signal symbol S1 and the data symbol D1; the cyclic prefix CP4 is located between the data symbol D1 and the data symbol D2 to avoid symbol interference between the data symbol D1 and the data symbol D2. In other words, the cyclic prefixes CP1 to CP4 serve as guard intervals (GI) between adjacent symbols to avoid intersymbol interference (ISI).

[0033] Please refer to Figure 2A , which is a schematic diagram illustrating a wireless signal receiving device and a drone according to an embodiment of the present application. Figure 2A As shown, the wireless signal receiving device 1 can be a base station installed on the ground, and can perform wireless communication with the base station carried by the drone 2 through the OFDM system to perform data transmission.

[0034] It should be noted that the drone 2 has the functions of image capture, positioning, wireless communication, audio sensing and temperature sensing, that is, the functions of the drone 2 are the same as those of existing drones. Of course, the functions of the drone 2 can also be increased according to actual application requirements (such as speed sensing and distance sensing), and this does not limit the functions of the drone 2. The base station carried by the drone 2 is a 5G NR mobile communication small cellular base station.

[0035] See also Figure 2B , which is a configuration diagram of a wireless signal receiving device according to an embodiment of the present application. Figure 2B As shown, and with Figure 2A , the wireless signal receiving device 1 includes a plurality of antennas 10 and a processor 20. The plurality of antennas 10 form an antenna array, and one of the plurality of antennas 10 receives the pilot signal and speed of the drone 2. It should be noted that the signal transmitted from the base station of the drone 2 to the antenna 10 is an initial pilot signal, and the initial pilot signal is converted into a pilot signal due to the Doppler effect; that is, the initial pilot signal is a pilot signal without the Doppler effect, and the pilot signal received by the antenna 10 is the initial pilot signal after the Doppler effect. The processor 20 is electrically connected to the antenna and executes a ground signal downlink reception and synchronization algorithm, which will be described in the corresponding paragraph of the wireless signal receiving method. The processor 20 may be a central processing unit or other types of processors, and is not limited to the scope listed in this application.

[0036] Please refer to Figure 3 , which is a flow chart of a wireless signal receiving method according to an embodiment of the present application. Figure 3 As shown, the wireless signal receiving method includes step S10 and step S20. Figure 3 The wireless signal receiving method shown is applicable to Figure 2A and Figure 2B The wireless signal receiving device 1 shown in the figure is not limited thereto. Figure 2A and Figure 2B The wireless signal receiving device 1 shown illustrates step S10 and step S20 as follows.

[0037] Step S10 : Receive the pilot signal and speed of the drone 2 . As mentioned above, the processor 20 receives the pilot signal and speed of the drone 2 through the antenna 10 .

[0038] Step S20: Execute the ground signal downlink reception and synchronization algorithm. Specifically, the processor 20 executes the ground downlink reception and synchronization algorithm on the pilot signal to perform Doppler offset compensation on the pilot signal and solve the problem of signal synchronization deviation between the wireless signal receiving device 1 and the drone 2.

[0039] The following will introduce the ground link reception and synchronization algorithm in detail. Please refer to Figure 4 , which is a flow chart illustrating a terrestrial signal downlink reception and synchronization algorithm according to an embodiment of the present application. Figure 4 As shown, the terrestrial signal downlink receiving and synchronization algorithm includes steps S21 to S25.

[0040] Step S21: Calculate the signal arrival angle θ according to the position of the drone 2, the position of the antenna 10, and the transmission direction of the pilot signal. Specifically, the drone 2 measures the height of the drone 2 relative to the ground and the distance between the drone 2 and the antenna 10 in the transmission direction of the pilot signal, and transmits the height of the drone 2 relative to the ground and the distance between the drone 2 and the antenna 10 in the transmission direction of the pilot signal to the processor 20. The processor 20 calculates the signal arrival angle θ according to the height of the drone 2 relative to the ground and the distance between the drone 2 and the antenna 10 in the transmission direction of the pilot signal. The signal arrival angle θ is the angle between the central axis of the antenna 10 and the transmission direction of the pilot signal.

[0041] Step S22: Calculate the Doppler frequency shift according to the frequency, speed and signal arrival angle θ of the pilot signal. Specifically, the processor 20 generates a signal waveform diagram corresponding to the pilot signal according to the pilot signal, and obtains the frequency of the pilot signal from the signal waveform diagram of the pilot signal. Then, the processor 20 substitutes the frequency, speed and signal arrival angle of the pilot signal into the following formula 1 to obtain the Doppler frequency shift.

[0042]

[0043]

[0044]

[0045] Where f0 is the frequency of the pilot signal, θ is the signal arrival angle, v is the speed of drone 2, c is the speed of light, and f s is the frequency of the RF signal (i.e., the initial pilot signal without Doppler effect), and Y is the Lorentz factor. When the speed v of the drone 2 is much smaller than the speed of light c, the Lorentz factor γ is 1.

[0046] Step S23: adjusting the frequency of the pilot signal according to the Doppler frequency offset. Specifically, the processor 20 performs Doppler frequency offset compensation on the pilot signal with the Doppler frequency offset, and then adjusts the frequency of the pilot signal, so that the frequency of the adjusted pilot signal is consistent with the frequency of the initial pilot signal.

[0047] Step S24: According to the preset time point of the corresponding pilot signal, the appearance time point of the pilot signal in the data symbol is adjusted. Specifically, the memory of the processor 20 pre-stores the preset time point of the initial pilot signal in the data symbol, calculates the time difference between the preset time point and the appearance time point of the pilot signal in the data symbol, and adjusts the appearance time point of the pilot signal in the data symbol according to the time difference.

[0048] Step S25: Adjust the sampling time point of the data symbol according to the appearance time point. Due to the adjustment of the pilot signal at the appearance time point of the data symbol, the start time point and the end time point of the data symbol are changed. Therefore, the processor 20 adjusts the sampling time point of the data symbol according to the start time point and the end time point of the changed data symbol.

[0049] In the wireless signal receiving method of this embodiment, the problems of Doppler frequency offset and signal frame synchronization are solved by adjusting the frequency of the pilot signal and the appearance time point of the pilot signal at the data symbol.

[0050] See also Figure 5 , which is a flow chart of a wireless signal receiving method according to another embodiment of the present application. Figure 5 As shown, the wireless signal receiving method includes steps S1A to S7A, and steps S1A and S5A are Figure 3 Step S10 and Figure 4 The step S23 shown is the same and will not be described again. Figure 5 The wireless signal receiving method shown is applicable to Figure 2A and Figure 2BThe wireless signal receiving device 1 shown in the figure is not limited thereto. Figure 2A and Figure 2B The wireless signal receiving device 1 shown illustrates steps S1A to S7A as follows.

[0051] Step S2A: Estimating the signal arrival angle θ. Specifically, the processor 20 estimates the distance between the UAV 2 and the antenna 10 and the horizontal distance between the antenna 10 and the UAV 2 in the transmission direction of the pilot signal according to the relative position relationship between the antenna 10 and the UAV 2 and the transmission direction of the pilot signal, and estimates the signal arrival angle θ according to the distance between the UAV 2 and the antenna 10 and the horizontal distance between the antenna 10 and the UAV 2 in the transmission direction of the pilot signal.

[0052] Step S3A: Estimate Doppler frequency offset. Specifically, the memory of the processor 20 pre-stores the frequency of the initial pilot signal; the processor 20 generates a signal waveform diagram corresponding to the pilot signal based on the pilot signal, and obtains the frequency of the pilot signal from the signal waveform diagram of the pilot signal. Then, the processor 20 estimates the difference between the frequency of the initial pilot signal and the frequency of the pilot signal, and regards the aforementioned difference as the Doppler frequency offset. It should be noted that step S2A and step S3A can be executed synchronously. In addition, the processor 20 calculates the Doppler frequency offset based on the frequency, speed and signal arrival angle θ of the pilot signal, and verifies whether the Doppler frequency offset calculated in step S3A is correct based on the aforementioned Doppler frequency offset.

[0053] Step S4A: Estimating the appearance time point of the pilot signal in the data symbol. Specifically, the processor 20 obtains the data symbol including the pilot signal from the signal waveform diagram corresponding to the pilot signal, and estimates the appearance time point of the pilot signal in the data symbol from the data symbol including the pilot signal.

[0054] Step S6A: Adjust the appearance time point of the pilot signal in the data symbol. Since the number of initial pilot signals of a data symbol can be multiple, the number of pilot signals of a data symbol can be multiple, and the time interval between two adjacent pilot signals is fixed (i.e., a fixed number of OFDM symbols). The memory of the processor 20 pre-stores at least one preset time point and preset time interval of the appearance of the initial pilot signal in the data symbol. The processor 20 first obtains the appearance time point of the pilot signal that first appears in the data symbol, and calculates the time difference between the appearance time point of the pilot signal that first appears and the preset time point, and adjusts the appearance time point of the pilot signal that first appears according to the time difference. Then, based on the appearance time point of the first pilot signal that appears after adjustment, the processor 20 uses the preset time interval to calculate multiple appearance time points of multiple pilot signals other than the appearance time point of the first pilot signal.

[0055] Step S6A: Adjust the sampling time point of the data symbol. Due to the change of the multiple occurrence time points of the multiple pilot signals, the starting time point and the ending time point of the data symbol change accordingly. Therefore, the processor 20 adjusts the sampling time point of the data symbol according to the changed starting time point and the ending time point of the data symbol.

[0056] In the experience Figure 3 or Figure 4 After the wireless signal receiving method shown, Figure 2A and Figure 2B The wireless signal receiving device 1 shown needs to further confirm whether the Doppler frequency offset compensation and the time synchronization of the data symbol are completed, and confirm whether the drone is a system user. Please refer to Figure 6 , which is a flow chart illustrating a method for determining whether frequency synchronization and signal synchronization are completed to receive a data packet from a drone according to another embodiment of the present application. Figure 6 As shown, the wireless signal receiving method may further include a step of determining whether frequency synchronization and signal synchronization are completed to receive a data packet from the drone 2, and the step of determining whether frequency synchronization and signal synchronization are completed to receive a data packet from the drone 2 includes steps S31 to S40. Figure 2A and Figure 2B The wireless signal receiving device 1 shown illustrates steps S31 to S40 as follows. For convenience of explanation, the frequency of the adjusted pilot signal is set to the first frequency, and the frequency of the initial pilot signal is set to the second frequency. Accordingly, the sampling time point corresponding to the adjusted pilot signal is set to the first sampling time point, and the sampling time point corresponding to the initial pilot signal is set to the second sampling time point.

[0057] Step S31: Waiting to receive the first user identification code from the drone 2. Specifically, the processor 20 transmits a request signal to the base station of the drone 2 through the antenna 10 to request the drone 2 to transmit the first user identification code, and waits for the drone 2 to transmit the first user identification code according to the request signal. When the processor 20 receives the first user identification code of the drone 2 through the antenna 10, the processor 20 continues to execute step S32; when the processor 20 does not receive the first user identification code of the drone 2, the processor 20 continues to wait to receive the first user identification code from the drone 2.

[0058] Step S32: Determine whether the first frequency is consistent with the second frequency. Specifically, the processor 20 compares the value of the first frequency and the value of the second frequency to generate a first comparison result, and determines whether the frequency synchronization is completed according to the first comparison result. When the first comparison result is that the value of the first frequency is the same as the value of the second frequency, the processor 20 determines that the frequency synchronization is completed, and continues to execute step S34. When the first comparison result is that the value of the first frequency is different from the value of the second frequency, the processor 20 determines that the frequency synchronization is not completed, and continues to execute step S33.

[0059] Step S33: Re-execute the terrestrial signal downlink reception and synchronization algorithm. Specifically, the processor 20 re-executes the following Figure 4 Steps S21 to S25 are shown.

[0060] Step S34: Determine whether the first sampling time point and the second sampling time point are consistent. Specifically, the processor 20 compares the first sampling time point and the second sampling time point to generate a second comparison result, and determines whether the signal synchronization is completed according to the second comparison result. In addition, step S34 can be performed before step S32 or with step S32. Figure 6 The execution order of step S32 and step S34 shown is for illustration only and is not intended to limit the present application.

[0061] When the second comparison result is that the value at the first sampling time point is the same as the value at the second sampling time point, the processor 20 determines that the signal synchronization is completed and continues to execute step S36. When the second comparison result is that the value at the first sampling time point is different from the value at the second sampling time point, the processor 20 determines that the signal synchronization is not completed and continues to execute step S35.

[0062] Step S36: Determine whether the first user identification code is a qualified identification code. Specifically, the memory of the processor 20 stores the first preset identification code in advance, and the processor 20 compares the first user identification code with the first preset identification code to generate a third comparison result, and determines whether the first user identification code is a qualified identification code according to the third comparison result, so as to determine whether the drone 2 is a system user.

[0063] When the third comparison result is that the first user identification code and the first preset identification code are the same, the processor 20 determines that the first user identification code is a qualified identification code, the drone 2 is a system user, and the processor 20 continues to execute step S38. When the third comparison result is that the first user identification code and the first preset identification code are different, the processor 20 determines that the first user identification code is not a qualified identification code, the drone 2 is not a system user, and the processor 20 continues to execute step S37.

[0064] Step S37: Refuse to communicate with the drone 2. Since the drone 2 is not a system user, the processor 20 refuses to communicate with the drone 2.

[0065] Step S38: Transmit the second user identification code and the user encryption key to the drone 2. Specifically, the processor 20 transmits the second user identification code and the user encryption key to the base station of the drone 2 via the antenna 10, and the drone 2 determines whether the wireless signal receiving device 1 is a system base station according to the second user identification code and the user encryption key.

[0066] The drone 2 stores the second preset identification code and the preset encryption key, and compares the second user identification code and the user encryption key with the second preset identification code and the preset encryption key to generate a fourth comparison result, and determines whether the wireless signal receiving device 1 is a system base station according to the fourth comparison result. When the fourth comparison result shows that the second user identification code and the user encryption key are the same as the second preset identification code and the preset encryption key, the drone 2 determines that the wireless signal receiving device 1 is a system base station, and returns an approval signal to the wireless signal receiving device 1. When the fourth comparison result shows that the second user identification code is different from the second preset identification code or the user encryption key is different from the preset encryption key, the drone 2 determines that the wireless signal receiving device 1 is not a system base station, and transmits a retransmission request to the wireless signal receiving device 1 to request the wireless signal receiving device 1 to retransmit the second user identification code and the user encryption key, or does nothing to wait for the wireless signal receiving device 1 to retransmit the second user identification code and the user encryption key.

[0067] Step S39: Determine whether the consent signal is received from the drone 2. Specifically, the processor 20 determines whether the drone 2 agrees to transmit data with the wireless signal receiving device 1 according to the reception status of the consent signal.

[0068] When the antenna 10 receives the consent signal from the drone 2, the processor 20 determines that the drone 2 agrees to transmit data with the wireless signal receiving device 1, and then proceeds to step S40. When the antenna 10 does not receive the consent signal from the drone 2, the processor 20 determines that the drone 2 does not agree to transmit data with the wireless signal receiving device 1, and then returns to step S38.

[0069] Step S40: Receive data packets. Specifically, the processor 20 communicates with the drone 2 via the antenna 10 to receive data packets.

[0070] In the wireless signal receiving method of this embodiment, it is further determined whether the frequency synchronization and signal synchronization are completed, and when it is determined that the frequency synchronization and signal synchronization are completed, a system user verification procedure and a system base station verification procedure are performed to further determine whether the drone is a system user and whether the wireless signal receiving device is a system base station. When it is determined that the drone is a system user and the wireless signal receiving device is a system base station, data transmission is performed.

[0071] In summary, the wireless signal receiving device and the wireless signal receiving method of the present application correct the Doppler frequency offset and solve the signal frame synchronization problem by adjusting the frequency of the pilot signal and the sampling time point of the data symbol.

Claims

1. A wireless signal receiving device, arranged on the ground and communicating with a drone, characterized in that: include: An antenna, receiving a pilot signal and a speed of the UAV; A processor is electrically connected to the antenna and executes a terrestrial signal downlink reception and synchronization algorithm, wherein the terrestrial signal downlink reception and synchronization algorithm comprises the following steps: Calculating a signal arrival angle according to the position of the drone, the position of the antenna, and the transmission direction of the pilot signal; Calculating a Doppler frequency shift according to the frequency of the pilot signal, the speed, and the signal arrival angle; adjusting the frequency of the pilot signal according to the Doppler frequency offset; Adjusting the appearance time point of the pilot signal in the data symbol according to a preset time point corresponding to the pilot signal; as well as According to the adjusted occurrence time point, the sampling time point of the data symbol is adjusted.

2. The wireless signal receiving device according to claim 1, wherein: The step of adjusting the occurrence time point of the pilot signal at the data symbol according to the preset time point corresponding to the pilot signal comprises: Calculating the time difference between the preset time point and the occurrence time point; According to the time difference, the occurrence time point of the pilot signal at the data symbol is adjusted.

3. The wireless signal receiving device according to claim 1, wherein: The step of calculating the signal arrival angle according to the position of the drone, the position of the antenna, and the transmission direction of the pilot signal performed by the processor includes: Obtaining from the drone the height of the drone relative to the ground and the distance between the drone and the antenna in the transmission direction of the pilot signal; and The signal arrival angle is calculated according to the height and the distance.

4. The wireless signal receiving device according to claim 1, wherein: The signal arrival angle is the angle between the central axis of the antenna and the transmission direction of the pilot signal.

5. The wireless signal receiving device according to claim 1, wherein: The signal transmitted by the drone to the wireless signal receiving device is an initial pilot signal, and the initial pilot signal is converted into the pilot signal due to the Doppler effect.

6. The wireless signal receiving device according to claim 5, characterized in that: The frequency of the pilot signal after adjustment is the first frequency, the frequency of the initial pilot signal is the second frequency, the sampling time point of the pilot signal after adjustment is the first sampling time point, and the sampling time point of the initial pilot signal is the second sampling time point, and the processor further performs the following steps: receiving a first user identification code from the drone; determining whether the first frequency is the same as the second frequency; Determining whether the first sampling time point is consistent with the second sampling time point; When it is determined that the first frequency is the same as the second frequency, and the first sampling time point is consistent with the second sampling time point, determining whether the first user identification code is a qualified identification code; When it is determined that the first user identification code is the qualified identification code, transmitting a second user identification code and a user encryption key to the drone via the antenna; as well as A consent signal is received from the drone, and a data packet is received by communicating with the drone via the antenna.

7. The wireless signal receiving device according to claim 6, wherein: The processor further executes the following steps: when it is determined that the first frequency is different from the second frequency, or the first sampling time point is inconsistent with the second sampling time point, re-execute the terrestrial signal downlink reception and synchronization algorithm.

8. The wireless signal receiving device according to claim 6, wherein: The processor further executes the following steps: when it is determined that the first user identification code is not the qualified identification code, refusing to communicate with the drone.

9. A wireless signal receiving method, for use in a wireless signal receiving device comprising an antenna and a processor, wherein the wireless signal receiving device is disposed on the ground and communicates with a drone through the antenna, wherein: The wireless signal receiving method is executed by the processor and includes: receiving the pilot signal and speed of the drone through the antenna; Execute a terrestrial signal downlink reception and synchronization algorithm, the terrestrial signal downlink reception and synchronization algorithm comprising the following steps: Calculating a signal arrival angle according to the position of the drone, the position of the antenna, and the transmission direction of the pilot signal; Calculating a Doppler frequency shift according to the frequency of the pilot signal, the speed, and the signal arrival angle; adjusting the frequency of the pilot signal according to the Doppler frequency offset; According to a preset time point corresponding to the pilot signal, adjusting the time point at which the pilot signal appears in the data symbol; and According to the adjusted occurrence time point, the sampling time point of the data symbol is adjusted.

10. The wireless signal receiving method according to claim 9, wherein: The step of adjusting the occurrence time point of the pilot signal at the data symbol according to the preset time point corresponding to the pilot signal comprises: Calculating the time difference between the preset time point and the occurrence time point; and According to the time difference, the occurrence time point of the pilot signal at the data symbol is adjusted.

11. The wireless signal receiving method according to claim 9, wherein: Calculating the signal arrival angle according to the position of the drone, the position of the antenna, and the transmission direction of the pilot signal includes: Obtaining from the drone the height of the drone relative to the ground and the distance between the drone and the antenna in the transmission direction of the pilot signal; and The signal arrival angle is calculated according to the height and the distance.

12. The wireless signal receiving method according to claim 9, wherein: The signal transmitted by the drone to the wireless signal receiving device is an initial pilot signal, and the initial pilot signal is converted into the pilot signal due to the Doppler effect.

13. The wireless signal receiving method according to claim 12, wherein: The frequency of the pilot signal after adjustment is the first frequency, the frequency of the initial pilot signal is the second frequency, the sampling time point corresponding to the pilot signal after adjustment is the first sampling time point, and the sampling time point corresponding to the initial pilot signal is the second sampling time point, and the wireless signal receiving method further includes: receiving a first user identification code from the drone; determining whether the first frequency is the same as the second frequency; Determining whether the first sampling time point is consistent with the second sampling time point; When it is determined that the first frequency is the same as the second frequency, and the first sampling time point is consistent with the second sampling time point, determining whether the first user identification code is a qualified identification code; When it is determined that the first user identification code is the qualified identification code, transmitting a second user identification code and a user encryption key to the drone; and A consent signal is received from the drone, and a data packet is received by communicating with the drone via the antenna.

14. The wireless signal receiving method according to claim 13, wherein: The wireless signal receiving method further includes: when it is determined that the first frequency is different from the second frequency, or the first sampling time point is inconsistent with the second sampling time point, re-executing the terrestrial signal downlink receiving and synchronization algorithm.

15. The wireless signal receiving method according to claim 13, wherein: The wireless signal receiving method further includes: when it is determined that the first user identification code is not the qualified identification code, refusing to communicate with the drone.

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