Frequency offset compensation method and electronic equipment

Abstract

The invention discloses a frequency offset compensation method and electronic equipment, relates to the field of communication, and is used for respectively compensating crystal oscillator frequency offset and Doppler frequency offset when the electronic equipment performs satellite communication. The frequency offset compensation method comprises the following steps: obtaining a direction vector of an electronic device pointing to a satellite in an electronic device coordinate system according to a phase difference of downlink signals from the satellite received by a plurality of antennas; obtaining a direction vector of the electronic equipment pointing to the satellite in the earth coordinate system according to the direction vector of the electronic equipment pointing to the satellite in the electronic equipment coordinate system and the attitude information of the electronic equipment; obtaining the coordinates of the satellite in the earth coordinate system according to the direction vector of the electronic equipment pointing to the satellite in the earth coordinate system; according to the carrier frequency of the downlink signal emitted by the satellite and the coordinates of the satellite in the earth coordinate system at multiple moments, Doppler frequency offset and crystal oscillator frequency offset of the downlink signal are obtained; and compensating the carrier frequency of the uplink signal sent by the electronic equipment.

Description

Technical Field

[0001] The present application relates to the field of communications, and in particular to a frequency offset compensation method and electronic equipment. Background Art

[0002] When users use mobile phones and other electronic devices to communicate with satellites (for example, making satellite calls, transmitting data via satellite), the satellite moves very fast, so the radio frequency signal transmitted between the electronic device and the satellite will produce Doppler frequency deviation. In addition, there will be crystal oscillator frequency deviation between the electronic device and the satellite. The superposition of these two frequency deviations will cause the communication rate of the uplink signal to decrease, and may even cause the uplink link to be interrupted. Summary of the invention

[0003] The embodiments of the present application provide a frequency offset compensation method and an electronic device, which are used to compensate for the crystal oscillator frequency offset and the Doppler frequency offset of the electronic device when performing satellite communication.

[0004] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0005] In a first aspect, a frequency deviation compensation method is provided, which is applied to an electronic device, the method comprising: obtaining a direction vector of the electronic device pointing to the satellite in the electronic device coordinate system according to a phase difference of a downlink signal from a satellite received by multiple antennas; obtaining a direction vector of the electronic device pointing to the satellite in the earth coordinate system according to the direction vector of the electronic device pointing to the satellite in the electronic device coordinate system and attitude information of the electronic device; obtaining the coordinates of the satellite in the earth coordinate system according to the direction vector of the electronic device pointing to the satellite in the earth coordinate system; obtaining a Doppler frequency deviation and a crystal oscillator frequency deviation of the downlink signal according to the carrier frequency of the downlink signal transmitted by the satellite and the coordinates of the satellite in the earth coordinate system at multiple moments; and compensating the carrier frequency of the uplink signal sent by the electronic device according to the Doppler frequency deviation and the crystal oscillator frequency deviation.

[0006] The frequency deviation compensation method provided in the embodiment of the present application, when the electronic device does not obtain the satellite ephemeris and the position information of the electronic device, the electronic device calculates the direction vector of the electronic device pointing to the satellite in the electronic device coordinate system by using the phase difference of the downlink signal received by multiple antennas, and then calculates the direction vector of the electronic device pointing to the satellite in the earth coordinate system in combination with the attitude information of the electronic device, and then obtains the coordinates of the satellite in the earth coordinate system. According to the carrier frequency of the downlink signal transmitted by the satellite, and the coordinates of the satellite in the earth coordinate system at multiple times, the Doppler frequency deviation and crystal oscillator frequency deviation of the downlink signal can be obtained. Then, the crystal oscillator frequency deviation and Doppler frequency deviation of the carrier frequency of the uplink signal are compensated respectively. Avoid reducing the communication rate of the uplink signal, and avoid uplink interruption.

[0007] In a possible implementation, the electronic device includes a first antenna, a second antenna, and a third antenna, and a direction vector of the electronic device pointing to the satellite is obtained in the electronic device coordinate system according to the phase difference of downlink signals from the satellite received by the multiple antennas, including: the phase difference of the downlink signals received by the first antenna and the second antenna is Δω1, and the phase difference of the downlink signals received by the first antenna and the third antenna is Δω2; the spacing between the first antenna and the second antenna is d1, and the spacing between the first antenna and the third antenna is d2; in the electronic device coordinate system, the unit vector of the first antenna pointing to the second antenna is m1=(0,1,0), the unit vector of the first antenna pointing to the third antenna is m2=(-1,0,0), the azimuth angle of the satellite relative to the electronic device is θ, the pitch angle is σ, and the direction vector of the electronic device pointing to the satellite is w U_US =(cosσcosθ,cosσsinθ,sinσ); By solving the following simultaneous equations, we can obtain the direction vector w of the electronic device pointing to the satellite in the electronic device coordinate system. U_US :

[0008]

[0009] The electronic device may also include more antennas, and the positions of these antennas are not limited. These antennas are coplanar but not colinear. In this way, these antennas meet the requirements of triangulation positioning, and the calculated relative position of the satellite and the electronic device is more accurate.

[0010] In a possible implementation, the attitude information of the electronic device includes a roll angle α, a pitch angle β, and a yaw angle γ; according to the direction vector of the electronic device pointing to the satellite in the electronic device coordinate system and the attitude information of the electronic device, the direction vector of the electronic device pointing to the satellite in the earth coordinate system is obtained, including: an X coordinate from the electronic device coordinate system to the earth coordinate system UE The axis rotation matrix is Y UE The axis rotation matrix is Z UE The axis rotation matrix is Specifically, as shown in the following formula, in the Earth coordinate system, the direction vector w of the electronic device pointing to the satellite is E_US for

[0011]

[0012] This implementation achieves the conversion of the direction vector of the electronic device pointing to the satellite from the electronic device coordinate system to the earth coordinate system. The attitude of the electronic device is different, the azimuth angle θ and the pitch angle σ of the satellite relative to the electronic device may also be different, the phase difference of the downlink signal from the satellite received by multiple antennas may also be different, and the direction vector of the electronic device pointing to the satellite will also be different, so combined with the attitude information of the electronic device, the direction vector of the electronic device pointing to the satellite in the earth coordinate system will be calculated to be more accurate.

[0013] In a possible implementation, the coordinates of the satellite in the earth coordinate system are obtained according to the direction vector of the electronic device pointing to the satellite in the earth coordinate system, including: the coordinate r of the satellite in the earth coordinate system is r=[x S ,y S ,z S ], the radius of the earth is R, the altitude of the satellite orbit is h, and the distance between the satellite and the electronic device is L US , then the coordinates r of the satellite in the Earth coordinate system are obtained by solving the following set of simultaneous equations:

[0014]

[0015] L US *w E_US =r.

[0016] This implementation achieves the conversion from the direction vector of the electronic device pointing to the satellite to the position coordinates of the satellite.

[0017] In a possible implementation, the Doppler frequency deviation and the crystal oscillator frequency deviation of the downlink signal are obtained according to the carrier frequency of the downlink signal transmitted by the satellite and the coordinates of the satellite in the earth coordinate system at multiple times, including: the carrier frequency of the downlink signal transmitted by the satellite is f S , the speed of light is c, and the velocity vector v of the satellite in the Earth coordinate system S To fit the satellite coordinates r in the earth coordinate system at multiple times and then differentiate them, the Doppler frequency deviation f of the downlink signal is d Obtained by the following formula:

[0018]

[0019] The carrier frequency deviation of the downlink signal estimated by the electronic device is Δf, so the crystal oscillator frequency deviation is f o Obtained by the following formula:

[0020] f o =Δf-f d .

[0021] Since the satellite is in constant motion, v SIt means fitting the coordinates r of the satellite in the Earth coordinate system at multiple times and then taking the derivative, the velocity vector v S Indicates the direction and speed of the satellite's movement.

[0022] In a possible implementation, the carrier frequency of the uplink signal sent by the electronic device is compensated according to the Doppler frequency deviation and the crystal oscillator frequency deviation, including: adding the crystal oscillator frequency deviation to the carrier frequency of the uplink signal and subtracting the Doppler frequency deviation.

[0023] Since the carrier frequency needs to be added with the crystal oscillator frequency deviation and the Doppler frequency deviation needs to be subtracted, that is, the processing methods for these two frequency deviations are different, if the Doppler frequency deviation and the crystal oscillator frequency deviation are compensated as a whole, the carrier frequency of the uplink signal received by the satellite will include twice the Doppler frequency deviation. Therefore, this implementation method can well pre-compensate the carrier frequency of the uplink signal by using different processing methods for these two frequency deviations, and finally make the carrier frequency of the uplink signal received by the satellite the same as the carrier frequency of the RF signal transmitted by the satellite, avoiding the reduction of the communication rate of the uplink signal, and avoiding the interruption of the uplink link.

[0024] In a second aspect, an electronic device is provided, comprising a processor and a memory, wherein instructions are stored in the memory, and when the processor executes the instructions, the method described in the first aspect and any embodiment thereof is executed.

[0025] According to a third aspect, a computer-readable storage medium is provided, which stores instructions. When the instructions are executed on an electronic device, the electronic device executes the method according to the first aspect and any embodiment thereof.

[0026] In a fourth aspect, a computer program product is provided, comprising instructions, which, when executed on the electronic device, cause the electronic device to execute the method as described in the first aspect and any of its embodiments.

[0027] The technical effects of the second to fourth aspects refer to the technical effects of the first aspect and any of its embodiments, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of a communication system provided in an embodiment of the present application;

[0029] Figure 2 A schematic diagram of a coordinate system of an electronic device provided in an embodiment of the present application;

[0030] Figure 3 A schematic diagram of the appearance of an electronic device provided in an embodiment of the present application;

[0031] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application;

[0032] Figure 5 A schematic diagram of a software architecture of an electronic device provided in an embodiment of the present application;

[0033] Figure 6 A flowchart of a frequency offset compensation method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] First, some concepts involved in this application are described.

[0035] The terms "first", "second", etc. involved in the embodiments of the present application are only used to distinguish features of the same type and cannot be understood as indicating relative importance, quantity, order, etc.

[0036] The terms "exemplary" or "for example" and the like in the embodiments of the present application are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the terms "exemplary" or "for example" is intended to present the related concepts in a specific way.

[0037] The terms "coupling" and "connection" involved in the embodiments of the present application should be understood in a broad sense. For example, they may refer to a direct physical connection, or an indirect connection achieved through electronic devices, such as a connection achieved through resistors, inductors, capacitors or other electronic devices.

[0038] The embodiments of the present application can be applied to satellite communication scenarios, such as Figure 1 As shown, an embodiment of the present application provides a communication system, including an electronic device 101 and a satellite 201. The communication system can be used for positioning and navigation of the electronic device, and can also be used for data communication and voice communication between the electronic device and the satellite. The concepts involved in satellite communication are as follows:

[0039] Earth coordinate system: Figure 1 As shown, the earth coordinate system takes the electronic device 101 as the origin and the north direction as the X EARTH Axis, due east is Y EARTH Axis, the direction of the line connecting the center of the earth and the electronic device 101 is Z EARTH axis.

[0040] Electronic equipment coordinate system: Figure 2 As shown, it is assumed that the display screen of the electronic device 101 is the front of the electronic device, and the user faces the display screen when using the electronic device. The electronic device coordinate system takes the center of the electronic device 101 as the origin, and the direction parallel to the long side of the electronic device 101 as the X UE Axis, with the direction parallel to the short side of the electronic device 101 as YUE Axis, perpendicular to X UE Y UE The axis of the plane is Z UE Axis. Electronics revolve around Z UE The angle of the clockwise rotation of the axis is the yaw angle γ, and the electronic device rotates around the X UE The angle of the axis rotating clockwise is the roll angle α, and the electronic device rotates around the Y UE The angle of the axis rotating clockwise is the pitch angle β.

[0041] like Figure 2 As shown, in the electronic device coordinate system, the relative relationship between the satellite 201 and the electronic device 101 can be described by the pitch angle σ and the azimuth angle θ of the satellite 201 relative to the electronic device 101. The pitch angle σ refers to the line connecting the origin of the electronic device coordinate system and the satellite 201 and the X-axis of the electronic device coordinate system. UE Y UE The angle between the planes, the pitch angle σ ranges from 0 degrees to 90 degrees. The azimuth angle θ refers to the X UE Y UE Projection in the plane and X UE The angle between the axes, azimuth θ around Z UE The axis rotates clockwise as positive, and the azimuth angle θ ranges from 0 degrees to 360 degrees.

[0042] Crystal oscillator frequency deviation: Electronic devices or satellites all include crystal oscillators (or oscillators), which are used to generate carrier signals. The radio frequency signals transmitted between electronic devices and satellites are obtained by mixing baseband signals and carrier signals. The difference between the crystal oscillator frequency of the electronic device and the crystal oscillator frequency of the satellite is the crystal oscillator frequency deviation, which will cause the carrier frequency of the radio frequency signals transmitted between the electronic device and the satellite to deviate.

[0043] Doppler frequency deviation: Since the satellite moves very fast and the electronic device moves very slowly, the relative speed between the electronic device and the satellite is high. When the electronic device and the satellite move in relative directions, the frequency of the RF signal received by the receiver will be higher than the carrier frequency when the sender transmits (i.e., the Doppler frequency deviation is positive). When the electronic device and the satellite move in opposite directions, the frequency of the RF signal received by the receiver will be lower than the carrier frequency when the sender transmits (i.e., the Doppler frequency deviation is negative). This difference is the Doppler frequency deviation.

[0044] Satellite ephemeris, also known as two-line orbital element (TLE), is used to describe information such as the satellite number and satellite orbit data. The satellite orbit data is used to describe the coordinates of the satellite as a function of time. The coordinates of the satellite can be determined at any time.

[0045] like Figure 3 As shown, an embodiment of the present application provides an electronic device 101, which can be mobile or fixed. The electronic device can be deployed on land (for example, indoors or outdoors, handheld or vehicle-mounted, etc.), on the water (for example, ships, etc.), or in the air (for example, airplanes, balloons, etc.). The electronic device can be called user equipment (UE), access terminal, terminal unit, subscriber unit, terminal station, mobile station (MS), mobile station, terminal agent or terminal device, etc. For example, the electronic device can be a mobile phone, a tablet computer, a laptop computer, a smart bracelet, a smart screen, a smart watch, a headset, a smart speaker, a terminal in industrial control, a terminal in self-driving, a terminal in remote medical care, a terminal in smart grid, a terminal in transportation safety, a terminal in smart city, a terminal in smart home, etc. The embodiment of the present application does not limit the specific type and structure of the electronic device.

[0046] The electronic device 101 may include Figure 3 The display screen 294 and the front camera 2931 shown in FIG. Figure 3 The main camera 2932 shown in B, the front camera 2931 and the display screen 294 are located on the same surface of the electronic device 101, and the main camera 2932 and the display screen 294 are located on different surfaces.

[0047] A possible structure of an electronic device is described below. Figure 4As shown, taking the electronic device 101 as a mobile phone as an example, at the hardware level, the electronic device 101 may include a processor 210, an external memory interface 220, an internal memory 221, a universal serial bus (USB) interface 230, a power management module 240, a battery 241, a wireless charging coil 242, an antenna 1, an antenna 2, a mobile communication module 250, a wireless communication module 260, an audio module 270, a speaker 270A, a receiver 270B, a microphone 270C, an earphone interface 270D, a sensor module 280, a button 290, a motor 291, an indicator 292, a camera 293, a display screen 294, and a subscriber identification module (SIM) card interface 295. Optionally, in some embodiments, an audio digital signal processor (ADSP) 243 is also included.

[0048] It is understood that the structure illustrated in the embodiment of the present application does not constitute a specific limitation on the electronic device 101. In other embodiments of the present application, the electronic device 101 may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0049] The processor 210 may include one or more processing units, for example, the processor 210 may be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), a central processing unit (CPU), an application processor (AP), a network processor (NP), a digital signal processor (DSP), a microcontroller unit (MCU), a programmable logic device (PLD), a modem processor, a graphics processor (GPU), an image signal processor (ISP), a controller, a video codec, a baseband processor, and a neural network processor (NPU). Among them, different processing units may be independent devices or integrated into one or more processors. For example, the processor 210 may be an application processor AP. Alternatively, the processor 210 may be integrated into a system on chip (SoC). Alternatively, the processor 210 may be integrated into an integrated circuit (IC) chip. The processor 210 may include an analog front end (AFE) and a micro-controller unit (MCU) in an IC chip.

[0050] ADSP 243 can be coupled with audio module 270 and sensor module 280, and ADSP 243 can be used to process audio signals and sensor data. When the processor is in a dormant state, ADSP 243 can still keep working, thereby reducing the power consumption of the electronic device.

[0051] It is understandable that the interface connection relationship between the modules illustrated in the embodiment of the present application is only a schematic illustration and does not constitute a structural limitation on the electronic device 101. In other embodiments of the present application, the electronic device 101 may also adopt different interface connection methods in the above embodiments, or a combination of multiple interface connection methods.

[0052] The external memory interface 220 can be used to connect an external memory card, such as a micro SanDisk (Micro SD) card, to expand the storage capacity of the electronic device 101. The external memory card communicates with the processor 210 through the external memory interface 220 to implement a data storage function, such as storing music, video and other files in the external memory card.

[0053] The internal memory 221 can be used to store computer executable program codes, which include computer instructions. The processor 210 executes various functional applications and data processing of the electronic device 101 by running the computer instructions stored in the internal memory 221, such as executing the frequency offset compensation method involved in the embodiment of the present application. In addition, the internal memory 221 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash storage (UFS), etc.

[0054] The memory involved in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0055] The electronic device 101 can implement audio functions such as music playing and recording through the audio module 270, the speaker 270A, the receiver 270B, the microphone 270C, the headphone interface 270D and the application processor.

[0056] The audio module 270 is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signal. In some embodiments, the audio module 270 can be arranged in the processor 210, or some functional modules of the audio module 270 can be arranged in the processor 210. The speaker 270A, also known as the "speaker", is used to convert the audio electrical signal into a sound signal. The receiver 270B, also known as the "earpiece", is used to convert the audio electrical signal into a sound signal. The microphone 270C, also known as the "microphone", is used to convert the sound signal into an electrical signal. The electronic device 101 can be provided with at least one microphone 270C. The headphone interface 270D is used to connect a wired headset. The headphone interface 270D can be a USB interface 230, or it can be a 3.5mm open mobile terminal platform (OMTP) standard interface, or a cellular telecommunications industry association of the USA (CTIA) standard interface.

[0057] The button 290 includes a power button, a volume button, etc. The button 290 may be a mechanical button. It may also be a touch button. The electronic device 101 may receive a button input and generate a key signal input related to the user settings and function control of the electronic device 101. The motor 291 may generate a vibration prompt. The motor 291 may be used for an incoming call vibration prompt or for touch vibration feedback. The indicator 292 may be an indicator light, which may be used to indicate the charging status, the change in power, or may be used to indicate messages, missed calls, notifications, etc. The SIM card interface 295 is used to connect a SIM card. The SIM card may be inserted into or removed from the SIM card interface 295 to achieve contact and separation with the electronic device 101. The electronic device 101 may support 1 or N SIM card interfaces, where N is a positive integer greater than 1. The SIM card interface 295 may support a Nano SIM card, a Micro SIM card, a SIM card, etc. In some embodiments, the electronic device 101 uses an embedded SIM (eSIM) card. The eSIM card can be embedded in the electronic device 101 and cannot be separated from the electronic device 101.

[0058] The electronic device 101 can realize the display function through a GPU, a display screen 294, and an application processor. The GPU is a microprocessor for image processing, which connects the display screen 294 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. The processor 210 may include one or more GPUs, which execute computer instructions to generate or change display information.

[0059] The sensor module 280 may include a pressure sensor, a gyroscope or gravity sensor, an air pressure sensor, a magnetic field sensor, an acceleration sensor, a distance sensor, a structured light sensor, a proximity light sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, and the like.

[0060] The battery 241 may include one or more batteries to power the load.

[0061] The power management module 240 is used to receive charging input from a charger. The charger may be a wireless charger, such as a wireless charging base, other electronic devices 101 with reverse wireless charging function, etc. The power management module 240 may receive wireless charging input through a wireless charging coil 242 of the electronic device. The charger may also be a wired charger, for example, the power management module 240 may receive charging input from a wired charger through the USB interface 230. The power management module 240 is also called a charging chip.

[0062] The power management module 240 can charge the battery 241 and also power the electronic device. The power management module 240 receives input from the battery 241 and powers the processor 210, the internal memory 221, the external memory interface 220, the display screen 294, the camera 293, and the wireless communication module 260. The power management module 240 can also be used to monitor the capacity, voltage, battery cycle number, battery health status (leakage, impedance) and other parameters of the battery 241. In some other embodiments, the power management module 240 can also be set in the processor 210.

[0063] The display screen 294 is used to display images, videos, etc. The display screen 294 includes a display panel. In some embodiments, the electronic device 101 may include one or more display screens 294 .

[0064] The camera 293 is used to capture static images or dynamic videos (collectively referred to as images). In some embodiments, the electronic device 101 may include 1 or N cameras 293, where N is a positive integer greater than 1. The camera 293 generally includes an optical lens and a photosensitive element. The photosensitive element may be any photosensitive device such as a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). In the process of capturing an image, the reflected light of the object being photographed is projected onto the photosensitive element after passing through the optical lens. The photosensitive element converts the received light signal into an electrical signal, which is sent to the processor 210 after being processed by the ISP. The processor 210 then obtains a frame of image. The camera 293 may include: Figure 3 The front camera 2931 shown in A and Figure 3 Main camera 2932 shown in B.

[0065] The processor 210 may also be provided with a memory for storing computer instructions and data. In some embodiments, the memory in the processor 210 is a cache memory. The memory may store computer instructions or data that the processor 210 has just used or circulated. If the processor 210 needs to use the computer instructions or data again, it may be directly called from the memory. This avoids repeated access, reduces the waiting time of the processor 210, and thus improves the efficiency of the system.

[0066] In some embodiments, the processor 210 may include one or more interfaces. The interface may include an inter-integrated circuit (I2C) interface, an inter-integrated circuit sound (I2S) interface, a pulse code modulation (PCM) interface, a universal asynchronous receiver / transmitter (UART) interface, a mobile industry processor interface (MIPI), a general-purpose input / output (GPIO) interface, a subscriber identity module (SIM) interface, and / or a USB interface, etc.

[0067] The wireless communication function of the electronic device 101 can be implemented through the antenna 1, the antenna 2, the mobile communication module 250, the wireless communication module 260, the modem processor, the baseband processor, and the like.

[0068] Antenna 1 and antenna 2 are used to transmit and receive electromagnetic wave signals. Each antenna in electronic device 101 can be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve the utilization of antennas. For example, antenna 1 can be reused as a diversity antenna for a wireless local area network. In some other embodiments, the antenna can be used in combination with a tuning switch.

[0069] The mobile communication module 250 can provide solutions for wireless communications including 2G / 3G / 4G / 5G, etc., applied to the electronic device 101. The wireless communication module 260 can provide solutions for wireless communications including wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), bluetooth (BT), global navigation satellite system (GNSS), satellite communications (such as data communications and voice communications), frequency modulation (FM), near field communication technology (NFC), infrared technology (IR), etc., applied to the electronic device 101. For example, the wireless communication module 260 can include a satellite communication chip to achieve satellite communication. For another example, the antenna 1 of the electronic device 101 is coupled to the mobile communication module 250, and the antenna 2 is coupled to the wireless communication module 260, so that the electronic device 101 can communicate with the network and other devices through wireless communication technology.

[0070] like Figure 5 As shown, taking an electronic device running the Android operating system as an example, the software architecture running on the processor includes an application layer, a framework layer, a system runtime layer, a hardware abstraction layer (HAL) layer, and a kernel layer.

[0071] The kernel layer is the layer between hardware and software. Exemplarily, the kernel layer includes display driver, camera driver, sensor driver, satellite communication chip driver, etc. The display driver is used to drive the display screen to display images or receive user touch operations, the camera driver is used to drive the camera to collect images, the sensor driver is used to drive the ADSP to obtain sensor data from various sensors, and the satellite communication chip driver is used to drive the satellite communication chip to perform satellite communication.

[0072] The HAL layer is used to abstract the hardware. The HAL layer hides the hardware interface details of a specific platform and provides a virtual hardware platform for the operating system, which is hardware-independent. For example, the HAL layer includes display modules, camera modules, sensor modules, satellite communication chip modules, etc. The display module is used for the virtual display screen, the camera module is used for the virtual camera, the sensor module is used for the virtual camera, and the satellite communication chip module is used for the virtual satellite communication chip.

[0073] The system runtime layer includes C / C++ program libraries and runtime libraries. Many core components and services of the Android operating system are built from native code and need to be written in C and C++ as C / C++ program libraries. When an application is installed for the first time, it will be pre-compiled into a runtime library in the form of machine code. This process is called pre-compilation. In this way, when the application is started and executed, it can be accelerated by running the machine code.

[0074] The framework layer provides an application programming interface (API) and a programming framework for the application programs in the application layer. The framework layer includes some predefined functions. For example, the framework layer includes a window manager, a content provider, a view system, a notification manager, etc. In particular, the framework layer also includes a satellite communication module for executing the frequency offset compensation method of the present application.

[0075] The application layer may include a series of application packages, such as satellite communication, camera, call, game, short video application, etc. Among them, the satellite communication application is used to perform satellite communication related functions, such as displaying the satellite star interface, displaying the satellite communication interface, etc.

[0076] In the scenario where an electronic device is communicating with a base station located on the ground, when the electronic device receives a downlink signal from the base station, it estimates the frequency deviation between the crystal oscillator frequency of the base station and the crystal oscillator frequency of the electronic device itself, that is, the crystal oscillator frequency deviation. When sending an uplink signal to the base station, it pre-compensates the uplink signal according to the crystal oscillator frequency deviation to eliminate the crystal oscillator frequency deviation in the uplink signal received by the base station. Since the relative speed between the electronic device and the base station is low, the Doppler frequency deviation between the electronic device and the base station does not need to be considered in this scenario.

[0077] But in Figure 1 In the scenario shown in FIG. 1 , the electronic device is communicating with a satellite. The relative speed between the electronic device and the satellite is high, and the Doppler frequency deviation between the electronic device and the satellite is obvious, so that the downlink signal received by the electronic device from the satellite includes not only the crystal oscillator frequency deviation but also the Doppler frequency deviation. Assume that when the electronic device is stationary relative to the ground, the carrier frequency of the downlink signal sent by the satellite is f S , the carrier frequency of the uplink signal generated by the electronic device is f U, the speed of the satellite relative to the electronic device is v, and the angle between the line between the satellite and the electronic device and the direction of the satellite's advance is The speed of light is c, then the Doppler frequency deviation between the electronic device and the satellite is f d for The carrier frequency f of the downlink signal received by the electronic device rU f rU =f S +f d .

[0078] Without obtaining satellite ephemeris and the position information of the electronic device, the electronic device cannot separate the crystal oscillator frequency deviation and the Doppler frequency deviation. If the crystal oscillator frequency deviation and the Doppler frequency deviation are taken as a whole to pre-compensate the uplink signal sent by the electronic device, the carrier frequency deviation Δf of the uplink signal estimated by the electronic device is: Δf = f rU -f U =f S +f d -f U The carrier frequency f of the uplink signal actually sent by the electronic device tU is: f tU =f U +Δf=f S +f d The carrier frequency f of the uplink signal actually received by the satellite rS is: f rS =f tU +f d =f S +2f d .

[0079] That is to say, the carrier frequency f of the uplink signal received by the satellite rS This includes twice the Doppler frequency deviation. In near-Earth satellite communications, the maximum Doppler frequency deviation at a 2GHz carrier frequency can reach 22.5ppm, and twice the Doppler frequency deviation is 45ppm, which may cause the communication rate of the uplink signal to decrease, and may even cause the uplink to be interrupted.

[0080] The embodiment of the present application provides a frequency deviation compensation method. When the electronic device does not obtain the satellite ephemeris and the position information of the electronic device, the electronic device calculates the direction vector of the electronic device pointing to the satellite in the electronic device coordinate system through the phase difference of the downlink signal received by multiple antennas, and then calculates the direction vector of the electronic device pointing to the satellite in the earth coordinate system in combination with the attitude information of the electronic device, and then obtains the coordinates of the satellite in the earth coordinate system. According to the coordinates of the satellite in the earth coordinate system at multiple times, the movement direction and speed of the satellite relative to the electronic device can be obtained, and then the Doppler frequency deviation between the satellite and the electronic device can be obtained. The crystal oscillator frequency deviation can be obtained by subtracting the Doppler frequency deviation from the estimated carrier frequency deviation of the downlink signal. Then, the crystal oscillator frequency deviation and the Doppler frequency deviation of the carrier frequency of the uplink signal are compensated respectively. Avoid the communication rate of the uplink signal from being reduced, and avoid the uplink interruption. In the case of missing satellite ephemeris, inaccurate satellite ephemeris, or the positioning function of the electronic device is not turned on, the crystal oscillator frequency deviation and the Doppler frequency deviation of the uplink can still be compensated normally to improve the transmission reliability.

[0081] The frequency offset compensation method can be applied to scenarios where electronic devices perform satellite communications. During the communication between the electronic device and the satellite, such as making a satellite call, transmitting data via satellite, performing positioning or navigation via satellite, etc., the frequency offset compensation method is executed.

[0082] like Figure 6 As shown, the frequency offset compensation method provided in the embodiment of the present application includes S101-S105:

[0083] S101: The electronic device obtains a direction vector pointing from the electronic device to the satellite in the electronic device coordinate system according to the phase difference of downlink signals from the satellite received by multiple antennas.

[0084] The plurality of antennas include at least three antennas, for example, Figure 2 As shown, taking three antennas as an example, the first antenna 21 is located at the upper left corner of the electronic device 101 , the second antenna 22 is located at the upper right corner of the electronic device 101 , and the third antenna 23 is located at the lower left corner of the electronic device 101 .

[0085] Since the distance between the satellite 201 and the electronic device 101 is much greater than the distance between the antennas of the electronic device 101, it can be considered that the lines connecting the satellite 201 and the antennas are parallel, so the relative positions of the satellite 201 and the antennas can be uniformly described by the azimuth angle θ and the pitch angle σ of the satellite 201 relative to the electronic device 101. Assume that the electronic device 101 detects that the phase difference of the downlink signal received by the first antenna 21 and the second antenna 22 is Δω1, and the phase difference of the downlink signal received by the first antenna 21 and the third antenna 23 is Δω2. The spacing between the first antenna 21 and the second antenna 22 is d1, and the spacing between the first antenna 21 and the third antenna 23 is d2. In the electronic device coordinate system, the unit vector of the first antenna 21 pointing to the second antenna 22 is m1=(0,1,0), the unit vector of the first antenna 21 pointing to the third antenna 23 is m2=(-1,0,0), and the direction vector of the electronic device 101 pointing to the satellite 201 is w U_US =(cosσcosθ, cosσsinθ, sinσ). The direction vector w of the electronic device 101 pointing to the satellite 201 in the electronic device coordinate system can be obtained by solving the following simultaneous equations: U_US .

[0086]

[0087] It should be noted that the electronic device 101 may also include more antennas, and the positions of these antennas are not limited. These antennas are coplanar but not colinear. In this way, these antennas meet the requirements of triangulation positioning, and the calculated relative positions of the satellite and the electronic device are more accurate.

[0088] S102: The electronic device obtains a direction vector pointing from the electronic device to the satellite in the earth coordinate system according to the direction vector pointing from the electronic device to the satellite in the electronic device coordinate system and the attitude information of the electronic device.

[0089] Assume that in the electronic device coordinate system, the initial posture of the electronic device is as follows: the electronic device is parallel to the horizontal plane, Figure 2 The direction in which the first antenna 21 points to the second antenna 22 is the due east direction, and the direction in which the third antenna 23 points to the first antenna 21 is the due north direction. The posture of the electronic device at any time can be regarded as the electronic device moving around X from the initial posture UE Axis, Y UE Axis, Z UE The axis is rotated clockwise by angles α, β and γ.

[0090] That is to say, the posture information of the electronic device at any time includes: UE The angle of the axis rotating clockwise is the roll angle α, and the electronic device rotates around the Y UEThe angle of the axis rotating clockwise is the pitch angle β, the electronic device rotates around the Z UE The angle of the axis rotating clockwise is the yaw angle γ. The above-mentioned attitude information can be obtained by an attitude sensor in the electronic device. For example, the attitude sensor includes an acceleration sensor and a magnetic field sensor.

[0091] According to the attitude information of the electronic device, the X coordinate system from the electronic device coordinate system to the earth coordinate system can be obtained. UE The axis rotation matrix is Y UE The axis rotation matrix is Z UE The axis rotation matrix is The details are shown in the following formula:

[0092]

[0093]

[0094] Then in the Earth coordinate system, the direction vector w of the electronic device pointing to the satellite is E_US for

[0095] This step realizes the conversion of the direction vector of the electronic device pointing to the satellite from the electronic device coordinate system to the earth coordinate system. The attitude of the electronic device is different, the azimuth angle θ and the pitch angle σ of the satellite relative to the electronic device 101 may also be different, the phase difference of the downlink signal from the satellite received by multiple antennas may also be different, and the direction vector of the electronic device pointing to the satellite will also be different. Therefore, in combination with the attitude information of the electronic device, the direction vector of the electronic device pointing to the satellite in the earth coordinate system will be more accurate.

[0096] S103: The electronic device obtains the coordinates of the satellite in the earth coordinate system according to the direction vector pointing from the electronic device to the satellite in the earth coordinate system.

[0097] Assume that the coordinate r of the satellite in the Earth coordinate system is r = [x S ,y S ,z S ], the radius of the earth is R, the altitude of the satellite orbit is h, and the distance between the satellite and the electronic device is L US , then the coordinate r of the satellite in the earth coordinate system can be obtained by solving the following set of simultaneous equations.

[0098]

[0099] L US *w E_US =r

[0100] This step realizes the conversion from the direction vector of the electronic device pointing to the satellite to the spatial coordinates of the satellite.

[0101] S104: The electronic device obtains the Doppler frequency deviation and the crystal oscillator frequency deviation of the downlink signal according to the carrier frequency of the downlink signal transmitted by the satellite and the coordinates of the satellite in the earth coordinate system at multiple moments.

[0102] Assume that the carrier frequency of the downlink signal transmitted by the satellite is f S , the speed of light is c, and the velocity vector v of the satellite in the Earth coordinate system S To find the differential after fitting the coordinates r of the satellite in the Earth coordinate system at multiple moments. Since the satellite is in constant motion, the velocity vector v S It means fitting the coordinates r of the satellite in the Earth coordinate system at multiple times and then taking the derivative, the velocity vector v S Indicates the direction and speed of the satellite, then the Doppler frequency deviation f of the downlink signal d It can be obtained by the following formula.

[0103]

[0104] Assuming that the carrier frequency deviation of the downlink signal estimated by the electronic device is Δf, the crystal oscillator frequency deviation f o It can be obtained by the following formula.

[0105] f o =Δf-f d

[0106] S105: The electronic device compensates for the carrier frequency of the uplink signal sent by the electronic device according to the Doppler frequency deviation and the crystal oscillator frequency deviation.

[0107] The electronic device adds the crystal oscillator frequency deviation to the carrier frequency of the uplink signal sent, and subtracts the Doppler frequency deviation. For example, the crystal oscillator frequency of the satellite is 3kHz, the crystal oscillator frequency of the electronic device is 2.5kHz, and the crystal oscillator frequency deviation is 3-2.5=0.5kHz, then the carrier frequency of the uplink signal sent by the electronic device is added with the crystal oscillator frequency deviation of 0.5kHz. For another example, the satellite and the electronic device move in relative directions, and the Doppler frequency deviation between the satellite and the electronic device is 0.3kHz, then the carrier frequency of the uplink signal sent by the electronic device is subtracted from the Doppler frequency deviation of 0.3kHz. For another example, the satellite and the electronic device move in opposite directions, and the Doppler frequency deviation between the satellite and the electronic device is -0.3kHz, then the carrier frequency of the uplink signal sent by the electronic device is subtracted from the crystal oscillator frequency deviation of -0.3kHz (actually adding 0.3kHz).

[0108] Since the carrier frequency needs to add the crystal oscillator frequency deviation and subtract the Doppler frequency deviation, that is, the processing methods for these two frequency deviations are different, if the Doppler frequency deviation and the crystal oscillator frequency deviation are compensated as a whole, the carrier frequency of the uplink signal received by the satellite will include twice the Doppler frequency deviation. Therefore, by using different processing methods for these two frequency deviations, the carrier frequency of the uplink signal can be well pre-compensated, and ultimately the carrier frequency of the uplink signal received by the satellite is the same as the carrier frequency of the RF signal transmitted by the satellite, avoiding the reduction of the communication rate of the uplink signal and avoiding the interruption of the uplink link.

[0109] The frequency deviation compensation method and electronic device provided in the embodiment of the present application, when the electronic device does not obtain the satellite ephemeris and the position information of the electronic device, the electronic device calculates the direction vector of the electronic device pointing to the satellite in the electronic device coordinate system by using the phase difference of the downlink signal received by multiple antennas, and then calculates the direction vector of the electronic device pointing to the satellite in the earth coordinate system in combination with the attitude information of the electronic device, and then obtains the coordinates of the satellite in the earth coordinate system. The Doppler frequency deviation and crystal oscillator frequency deviation of the downlink signal can be obtained according to the carrier frequency of the downlink signal transmitted by the satellite, and the coordinates of the satellite in the earth coordinate system at multiple times. Then, the crystal oscillator frequency deviation and Doppler frequency deviation of the carrier frequency of the uplink signal are compensated respectively. Avoid reducing the communication rate of the uplink signal, and avoid uplink interruption.

[0110] The present application also provides a computer-readable storage medium, which includes instructions. When the instructions are executed on the electronic device, the electronic device executes each step in the method embodiment, such as executing Figure 6 The method shown.

[0111] The present application also provides a computer program product including instructions. When the instructions are executed on the electronic device, the electronic device executes each step in the method embodiment, such as executing Figure 6 The method shown.

[0112] Regarding the technical effects of the computer-readable storage medium and the computer program product, refer to the technical effects of the previous method embodiments.

[0113] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0114] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0115] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0116] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or may contain one or more servers, data centers and other data storage devices that can be integrated with the medium. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (eg, a solid state disk (SSD)).

[0117] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A frequency offset compensation method, characterized in that: Applied to electronic equipment, the method comprises: Obtaining a direction vector of the electronic device pointing to the satellite in the electronic device coordinate system according to the phase difference of the downlink signals from the satellite received by the multiple antennas; Obtaining a direction vector of the electronic device pointing to the satellite in the earth coordinate system according to the direction vector of the electronic device pointing to the satellite in the electronic device coordinate system and the attitude information of the electronic device; Obtaining the coordinates of the satellite in the earth coordinate system according to the direction vector of the electronic device pointing to the satellite in the earth coordinate system; According to the carrier frequency of the downlink signal transmitted by the satellite and the coordinates of the satellite in the earth coordinate system at multiple moments, the Doppler frequency deviation and the crystal oscillator frequency deviation of the downlink signal are obtained; The carrier frequency of the uplink signal sent by the electronic device is compensated according to the Doppler frequency deviation and the crystal oscillator frequency deviation.

2. The method according to claim 1, characterized in that The electronic device comprises a first antenna, a second antenna and a third antenna, and obtaining a direction vector pointing from the electronic device to the satellite in the electronic device coordinate system according to a phase difference of downlink signals from the satellite received by the multiple antennas comprises: The phase difference of the downlink signals received by the first antenna and the second antenna is Δω1, and the phase difference of the downlink signals received by the first antenna and the third antenna is Δω2; the distance between the first antenna and the second antenna is d1, and the distance between the first antenna and the third antenna is d2; in the electronic device coordinate system, the unit vector of the first antenna pointing to the second antenna is m1=(0,1,0), and the unit vector of the first antenna pointing to the third antenna is m2=(-1,0,0), the azimuth angle of the satellite relative to the electronic device is θ, the pitch angle is σ, and the direction vector of the electronic device pointing to the satellite is w U_US =(cosσcosθ, cosσsinθ, sinσ); By solving the following simultaneous equations, we can obtain the direction vector w of the electronic device pointing to the satellite in the electronic device coordinate system. U_US :

3. The method according to claim 1, characterized in that The attitude information of the electronic device includes a roll angle α, a pitch angle β, and a yaw angle γ; and according to the direction vector of the electronic device pointing to the satellite in the electronic device coordinate system and the attitude information of the electronic device, obtaining the direction vector of the electronic device pointing to the satellite in the earth coordinate system includes: X from the electronic device coordinate system to the earth coordinate system UE The axis rotation matrix is Y UE The axis rotation matrix is Z UE The axis rotation matrix is The details are shown in the following formula: Then in the Earth coordinate system, the direction vector w of the electronic device pointing to the satellite is E_US for 4. The method according to claim 1, characterized in that: The step of obtaining the coordinates of the satellite in the earth coordinate system according to the direction vector of the electronic device pointing to the satellite in the earth coordinate system comprises: The coordinate r of the satellite in the Earth coordinate system is r = [x S ,y S ,z S ], the radius of the earth is R, the altitude of the satellite orbit is h, and the distance between the satellite and the electronic device is L US , then the coordinates r of the satellite in the Earth coordinate system are obtained by solving the following set of simultaneous equations: L US *w E_US =r。 5. The method according to claim 1, characterized in that According to the carrier frequency of the downlink signal transmitted by the satellite and the coordinates of the satellite in the earth coordinate system at multiple moments, the Doppler frequency deviation and the crystal oscillator frequency deviation of the downlink signal are obtained, including: The carrier frequency of the downlink signal transmitted by the satellite is f S , the speed of light is c, and the velocity vector v of the satellite in the Earth coordinate system S To fit the coordinates r of the satellite in the earth coordinate system at multiple times and then obtain the differential, the Doppler frequency deviation f of the downlink signal is d Obtained by the following formula: The carrier frequency deviation of the downlink signal estimated by the electronic device is Δf, then the crystal oscillator frequency deviation f o Obtained by the following formula: f o =Δf-f d 。 6. The method according to claim 1, characterized in that The compensating the carrier frequency of the uplink signal sent by the electronic device according to the Doppler frequency deviation and the crystal oscillator frequency deviation includes: The crystal oscillator frequency deviation is added to the carrier frequency of the uplink signal, and the Doppler frequency deviation is subtracted.

7. An electronic device, characterized in that: The electronic device comprises a processor and a memory, wherein the memory stores instructions, and when the processor executes the instructions, the electronic device executes the method according to any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that: Instructions are stored, and when the instructions are executed on an electronic device, the electronic device executes the method according to any one of claims 1 to 6.

9. A computer program product, characterized in that The method comprises instructions, which, when executed on an electronic device, cause the electronic device to execute the method according to any one of claims 1 to 6.

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