Carrier synchronization method, carrier synchronization device, terminal device, computer readable storage medium, computer program product and chip system

Abstract

This application provides a carrier synchronization method, a carrier synchronization device, a terminal device, a computer-readable storage medium, a computer program product, and a chip system for a computing device. The method may include filtering a communication signal from a network device using a first filter to obtain a filtered signal, wherein the bandwidth of the first filter is determined based on the bandwidth of the communication signal and a first frequency offset range, and the first frequency offset range is determined based on the maximum frequency offset between the terminal device and the network device; performing coarse carrier synchronization processing on the filtered signal to determine a first signal; performing fine timing synchronization processing on the first signal to determine a second signal; and performing fine frequency offset synchronization and phase synchronization based on the second signal. This application allows signals within the frequency offset range to be received in a single operation, reducing network search time.

Description

Technical Field

[0001] This application relates to the field of wireless communication, and specifically to a carrier synchronization method, a carrier synchronization device, a terminal device, a computer-readable storage medium, a computer program product, and a chip system for computing devices. Background Technology

[0002] Compared to terrestrial communication, satellite communication has a wider coverage area and is not limited by specific regions, weather, terrain, power supply, or other ground infrastructure. It can overcome natural geographical barriers such as oceans, deserts, and mountains. Therefore, satellite communication can supplement terrestrial communication to overcome its shortcomings.

[0003] In satellite communication systems, a transparent relay mode is defined, allowing satellites to transmit and receive signals independently. Frequency offset in satellite communication systems can include offsets caused by the satellite's hardware clock, Doppler offsets caused by motion Doppler effects, and inherent frequency offsets of the satellite transponder. Large frequency offsets can affect the acquisition of communication signals by ground terminal equipment.

[0004] To eliminate frequency offset in communication signals, existing methods first use frequency sweeping technology to detect the signal strength. If the strength does not meet the expected value, the signal is moved in the positive or negative direction by a preset frequency offset step, and the signal strength is continued to be detected. When the strength meets the expected value, the received communication signal is synchronized. However, because the bandwidth of the signal that the frequency sweeping technology can receive cannot completely cover the entire frequency offset range, the sweeping time increases, affecting processing efficiency. Summary of the Invention

[0005] Providing a mechanism to alleviate, reduce or eliminate at least one of the above problems would be beneficial.

[0006] In a first aspect, a carrier synchronization method is provided, applied to a terminal device. The method includes: filtering a communication signal from a network device using a first filter to obtain a filtered signal, wherein the bandwidth of the first filter is determined based on the bandwidth of the communication signal and a first frequency offset range, the first frequency offset range being determined based on the maximum frequency offset between the terminal device and the network device; performing coarse carrier synchronization on the filtered signal to determine a first signal; performing fine timing synchronization on the first signal to determine a second signal; and performing fine frequency offset synchronization and phase synchronization on the first signal based on the second signal.

[0007] In a second aspect, a carrier synchronization apparatus is provided. The apparatus includes means for performing the aforementioned carrier synchronization method.

[0008] In a third aspect, a terminal device is provided. The terminal device includes: one or more processors; and one or more memories coupled to the one or more processors and storing instructions thereon. When the instructions are executed individually or jointly by the one or more processors, the terminal device performs any of the methods described above.

[0009] In a fourth aspect, a non-transitory computer-readable storage medium is provided that stores machine-executable instructions. When executed by one or more processors of a machine, the machine-executable instructions cause the machine to perform any of the methods described above.

[0010] In a fifth aspect, a computer program product is provided, including instructions that, when executed individually or jointly by at least one processor of a computing device, cause the computing device to perform any of the methods described above.

[0011] In a sixth aspect, a chip system for a computing device is provided, the chip system including at least one processor configured to execute, individually or collectively, at least one memory-stored instruction of the computing device to cause the computing device to perform any of the methods described above.

[0012] It should be understood that the summary section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0013] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of some embodiments thereof in the accompanying drawings, wherein:

[0014] Figure 1 The carrier synchronization method of some embodiments of this application is shown to be applicable to the architecture of a possible network communication system;

[0015] Figure 2 A schematic diagram of an NTN communication system to which the carrier synchronization method of some embodiments of this application is applicable is shown;

[0016] Figure 3 A flowchart illustrating a carrier synchronization method according to some embodiments of this application is shown;

[0017] Figure 4 A schematic diagram of the filtering bandwidth of some embodiments of this application is shown;

[0018] Figure 5 A schematic diagram of the architecture of a carrier synchronization device according to some embodiments of this application is shown;

[0019] Figure 6The diagram illustrates a scenario of implementing a carrier coarse synchronization module according to some embodiments of this application.

[0020] Figure 7 The illustration shows a schematic diagram of an implementation scenario for the timing precision synchronization module of some embodiments of this application;

[0021] Figure 8 The illustration shows a schematic diagram of an implementation scenario for the frequency offset fine synchronization module of some embodiments of this application;

[0022] Figure 9 The diagram illustrates implementation scenarios of the phase synchronization module in some embodiments of this application.

[0023] Figure 10 An exemplary schematic diagram of a terminal device is shown. Detailed Implementation

[0024] The principles of this application will now be described with reference to some embodiments. It should be understood that these embodiments are described for illustrative purposes only and to assist those skilled in the art in understanding and implementing this application, and do not impose any limitation on the scope of this application. The application described herein can be implemented in ways different from those described below.

[0025] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0026] References to "an embodiment," "embodiment," "exemplary embodiment," etc., in this application indicate that the described embodiment may include specific features, structures, or characteristics, but not every embodiment needs to include specific features, structures, or characteristics. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in conjunction with an exemplary embodiment, whether explicitly described or not, those skilled in the art will recognize that such a feature, structure, or characteristic affects its association with other embodiments.

[0027] It should be understood that while the terms “first” and “second”, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of the exemplary embodiments, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. The term “and / or” as used herein includes any and all combinations of one or more of the listed terms.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments. The singular forms “a,” “an,” and “the” used herein also include the plural forms unless the context clearly indicates otherwise. The terms “a group of elements” or “a collection of elements” as used herein are intended to include one or more elements. It should also be understood that the terms “comprising,” “including,” “having,” “possessing,” “including,” and / or “comprising,” when used herein, specify the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0029] As used in this application, the term "circuit" may refer to one or more of the following:

[0030] (a) Implemented only in hardware circuitry (e.g., implemented only in analog and / or digital circuitry)

[0031] (b) A combination of hardware circuitry and software, such as (if applicable):

[0032] (i) a combination of analog and / or digital hardware circuitry with software / firmware; and

[0033] (ii) Any part of a hardware processor (including a digital signal processor), software, and memory that work together to enable a device such as a mobile phone or server to perform various functions, and

[0034] (c) Hardware circuitry and / or processors, such as microprocessors or a portion thereof, which require software (e.g., firmware) to operate, but may be absent when the software is not required to operate.

[0035] The definition of "circuit" applies to all uses of the term in this application, including in any claim. As another example, as used herein, the term "circuit" also includes implementations of hardware circuitry or processors (or processors in general) or a portion thereof and their accompanying software and / or firmware. The term "circuit" also includes, for example, baseband integrated circuits or processor integrated circuits for mobile devices, or similar integrated circuits in servers, cellular network devices, or other computing network devices, if applicable to a particular claim element.

[0036] As used herein, the term "communication network" refers to a network that conforms to any suitable communication standard, such as Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), New Radio (NR), Non-Terrestrial Network (NTN), etc. Furthermore, communication between terminal devices and network devices in a communication network can be performed according to any suitable generation of communication protocol, including but not limited to first-generation (1G), second-generation (2G), 2.5G, 2.75G, third-generation (3G), fourth-generation (4G), 4.5G, fifth-generation (5G), and future sixth-generation (6G) communication protocols, and / or any other currently known or to be developed in the future. Embodiments of this application can be applied to satellite communication systems. Given the rapid development in communications, future types of communication technologies and systems will naturally exist, and this application can be implemented using these technologies and systems. It should not be considered that the scope of this application is limited to the aforementioned systems.

[0037] The term "terminal device" refers to any terminal device capable of wireless communication. As an example and not a limitation, a terminal device may also be referred to as a communication device, user equipment (UE), subscriber station (SS), portable subscriber station, mobile station (MS), or access terminal (AT). This terminal device may include, but is not limited to, mobile phones, cellular phones, smartphones, Voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), laptop installed devices (LMEs), USB dongles, smart devices, wireless subscriber equipment (CPEs), Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronics devices, relay nodes, devices operating on commercial and / or industrial wireless networks, etc. The mobile terminal (MT) portion of an IAB node can perform the functions of a "terminal device" and therefore can operate as a terminal device. In the following description, the terms "terminal device," "communication device," "terminal," "user equipment," and "UE" are used interchangeably.

[0038] As used in this article, the Physical Master Broadcast Channel (PMBCH) is an information channel that transmits information via broadcast.

[0039] As used in this article, "non-terrestrial networks" (NTNs) include nodes such as satellite networks, high-altitude platforms, and unmanned aerial vehicles (UAVs). They possess significant advantages such as global coverage, long-distance transmission, flexible networking, convenient deployment, and freedom from geographical limitations, and have been widely applied in various fields including maritime communication, positioning and navigation, disaster relief, scientific experiments, video broadcasting, and Earth observation. The integration of terrestrial mobile communication technologies and satellite networks, leveraging their respective strengths, together constitutes a seamless global integrated communication network encompassing sea, land, air, space, and ground, meeting the diverse and ubiquitous service needs of users.

[0040] As a crucial component of NTN, next-generation satellite networks are generally characterized by ultra-dense and heterogeneous structures. Firstly, the scale of satellite networks has grown from 66 satellites in the Iridium constellation to 720 in a single-network constellation, and ultimately extended to the Starlink ultra-dense low Earth orbit (LEO) satellite constellation of over 12,000 satellites. Secondly, satellite networks exhibit heterogeneous characteristics, evolving from traditional single-layer communication networks to multi-layered communication networks. The functions of communication satellite networks are also becoming more complex and diversified, gradually accommodating and supporting functions such as navigation enhancement, Earth observation, and on-orbit processing of multi-dimensional information.

[0041] As used herein, "Doppler frequency shift" refers to the change in phase and frequency caused by the difference in propagation path when one device moves at a certain speed relative to another device in a certain direction. In the embodiments of this application, Doppler frequency shift can also be called Doppler frequency offset, or simply frequency offset.

[0042] The carrier synchronization method provided in this application can be applied to fourth-generation (4G) communication systems, such as long-term evolution (LTE) systems; it can also be applied to fifth-generation (5G) communication systems, such as 5G new radio (NR); or to various future communication systems, such as sixth-generation (6G) communication systems. The method provided in this application can be applied to terrestrial network communication systems as well as non-terrestrial network (NTN) communication systems.

[0043] Figure 1 The carrier synchronization method of some embodiments of this application is illustrated to be applicable to the architecture of a possible network communication system. References Figure 1As shown, the communication system 100 may include network device 110 and terminal devices 101, 102, 103, 104, 105, and 106. It should be understood that the communication system 100 may include more or fewer network devices 110 or terminal devices. Network devices 110 or terminal devices may be hardware, functionally defined software, or a combination of both. Furthermore, terminal devices 104 to 106 may also form a communication system; for example, terminal device 105 may send downlink data to terminal device 104 or terminal device 106. Communication between network devices and terminal devices can occur through other devices or network elements. Network device 110 may send downlink data to terminal devices 101 to 106 and may also receive uplink data sent by terminal devices 101 to 106. Similarly, terminal devices 101 to 106 may send uplink data to network device 110 and may also receive downlink data sent by network device 110. Network device 110 is a node in a radio access network (RAN), also known as a base station or RAN node (or device). Examples of current access network devices 101 include: gNB / NR-NB, transmission reception point (TRP), evolved Node B (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (e.g., home evolved Node B, or home Node B, HNB), base band unit (BBU), or wireless fidelity (Wi-Fi) access point (AP), or network devices in 5G communication systems, or network devices in future communication systems. Network device 110 can also be other devices with network device functions; for example, network device 110 can also be a device that functions as a network device in D2D communication. Network device 110 could also be a network device in a future communication system.

[0044] Terminal devices 101 to 106, also known as user equipment (UE), mobile station (MS), or mobile terminal (MT), are devices that provide voice or data connectivity to users, and can also be Internet of Things (IoT) devices. For example, terminal devices 101 to 106 include handheld devices and vehicle-mounted devices with wireless connectivity. Currently, terminal devices 101 to 106 can be: mobile phones, tablets, laptops, handheld computers, mobile internet devices (MIDs), wearable devices (such as smartwatches, smart bracelets, pedometers, etc.), in-vehicle devices (such as cars, bicycles, electric vehicles, airplanes, ships, trains, high-speed trains, etc.), virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, smart home devices (such as refrigerators, televisions, air conditioners, electricity meters, etc.), smart robots, workshop equipment, wireless terminals in self-driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, or wireless terminals in smart homes, and flying devices (such as smart robots, hot air balloons, drones, airplanes), etc. Terminal devices 101 to 106 can also be other devices with terminal functions. For example, terminal devices 101 to 106 can also be devices that perform terminal functions in D2D communication.

[0045] based on Figure 1 The description of the terrestrial network communication system architecture shown in this application indicates that the carrier synchronization method provided in this embodiment can be applied to NTN communication systems. Figure 2An NTN communication system is illustrated, comprising a satellite 201 and a terminal device 202. The explanation of terminal device 202 can be found in the descriptions of terminal devices 101 to 106 above. Satellite 201 can also be referred to as a high-altitude platform, a high-altitude aircraft, or a satellite base station. The communication link between satellite 201 and terminal device 202 can be called a satellite link. In relation to a terrestrial network communication system, satellite 201 can be considered as one or more network devices within the terrestrial network communication system architecture. Satellite 201 provides communication services to terminal device 202, and satellite 201 can also connect to core network equipment. The structure and functions of satellite 201 can also be found in the description of network device 110 above. The communication method between satellite 201 and terminal device 202 can also be found in the descriptions above. Figure 1 The description in [the document] is omitted here.

[0046] Network devices in a terrestrial network communication system and satellites in an NTN communication system are collectively considered as network devices. The apparatus used to implement the functions of a network device can be a network device itself; it can also be an apparatus capable of supporting the network device in implementing that function, such as a chip system, which can be installed within the network device. In the following description of the technical solutions provided by the embodiments of this application, a satellite is used as an example to illustrate the technical solutions provided by the embodiments of this application. It is understood that when the methods provided by the embodiments of this application are applied to a terrestrial network communication system, the actions performed by the satellite can be applied to the base station or network device for execution.

[0047] In this application embodiment, the device for implementing the functions of the terminal device can be the terminal device itself, or it can be a device capable of supporting the terminal device in implementing the functions, such as a chip system, which can be installed in the terminal device. In this application embodiment, the chip system can be composed of chips, or it can include chips and other discrete devices. In the technical solutions provided in this application embodiment, the device for implementing the functions of the terminal device is a terminal or UE as an example to describe the technical solutions provided in this application embodiment.

[0048] In the embodiments of this application, the terms "information," "signal," "message," "channel," and "signaling" may sometimes be used interchangeably. It should be noted that, without emphasizing their distinction, they all convey the same meaning. Similarly, the terms "of," "corresponding (relevant)," and "corresponding" may sometimes be used interchangeably. It should be noted that, without emphasizing their distinction, they all convey the same meaning.

[0049] The satellite employs a transparent relay method, enabling both transmission and reception. This means that after receiving a communication signal, the satellite processes it and retransmits it to the target location, maintaining the original signal without alteration. Therefore, the frequency offset on the satellite link is primarily determined by the frequency offset caused by the satellite's hardware clock, the Doppler frequency offset due to motion Doppler effects, and the inherent frequency offset of the satellite transponder. The frequency offset on the satellite link is inversely proportional to the acquisition probability of the physical channel; a larger frequency offset results in a lower acquisition probability, making it more difficult for the terminal device to acquire the communication signal. Simultaneously, the acquisition probability of the physical channel is directly proportional to the symbol bandwidth; for a given frequency offset, a smaller symbol bandwidth results in a lower acquisition probability, making it more difficult for the terminal device to acquire the communication signal.

[0050] To eliminate frequency offset issues in the signal, current methods first detect the signal strength using frequency sweeping technology. If the signal strength does not meet the expected value, the signal is shifted in a preset frequency offset step, either positively or negatively, and the signal strength detection continues. When the signal strength meets the expected value, a frame synchronization process is initiated. During frame synchronization, the received signal is cross-correlated with the local sequence to obtain a correlation curve. The position of the correlation peak in the correlation curve represents the frame header position.

[0051] Currently, frequency sweeping technology mainly faces two key issues: 1. The bandwidth of the received signal cannot fully cover the entire frequency offset range, leading to an increase in sweeping time; 2. The computational load for pilot shift correlation is enormous over long periods. Cross-correlation, on the other hand, has the advantage of roughly estimating the position of a signal frame after its arrival, but its disadvantage is that it is greatly affected by frequency offset; the larger the frequency offset, the worse the cross-correlation performance.

[0052] To this end, this application provides a carrier synchronization method. A first filter is used to receive all valid signals within the frequency offset range at once and obtain a filtered signal. The filtered signal undergoes coarse carrier synchronization processing to determine a first signal. The first signal undergoes fine timing synchronization processing to determine a second signal. Finally, based on the second signal, the first signal undergoes fine frequency offset synchronization and phase synchronization to achieve carrier synchronization.

[0053] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0054] Please see Figure 3 , Figure 3 This is a flowchart illustrating a carrier synchronization method according to some embodiments of this application. The method 300 includes, but is not limited to, the following steps.

[0055] Step S310: The terminal device filters the communication signal from the network device through the first filter to obtain the filtered signal.

[0056] In step S310, in order to receive communication signals within the frequency offset range in one go without loss, the terminal device can set the filtering bandwidth of the first filter and receive communication signals within the filtering bandwidth.

[0057] Please see Figure 4 , Figure 4 This is a schematic diagram of the filtering bandwidth of the first filter in a carrier synchronization method according to an embodiment of this application. From Figure 4 It can be seen that the filtering bandwidth (B) of the first filter w The bandwidth (B) of the communication signal and the first frequency offset range are determined based on the maximum frequency offset (Δf) between the terminal device and the network device, i.e., B. w =B + 2 × Δf. The frequency offset (Δf) between the terminal device and the network device includes the frequency offset caused by the satellite's hardware clock, the Doppler frequency offset caused by the motion Doppler effect, and the terminal clock frequency offset.

[0058] The frequency offset of a hardware clock refers to the deviation between the hardware clock and the actual time. Because the accuracy of a hardware clock is affected by various factors, such as the stability of the clock crystal, temperature changes, and voltage fluctuations, the speed of the hardware clock may deviate. When the hardware clock runs faster than the actual time, the frequency offset is positive; when the hardware clock runs slower than the actual time, the frequency offset is negative.

[0059] When the satellite and the mobile terminal move relative to each other, the Doppler frequency offset is negative if the mobile terminal is far away from the satellite, and positive if the mobile terminal is close to the satellite.

[0060] Therefore, the maximum frequency offset range between the terminal device and the network device = [-Δf] max , Δf max When frequency offset occurs between the terminal equipment and the satellite, the communication signal will shift within the maximum frequency offset range. Therefore, the filtering bandwidth of the first filter is B. w =B + 2 × Δf max In this case, the terminal device can filter the communication signal from the network device through the first filter to obtain the filtered signal, thereby enabling it to receive communication signals within the frequency offset range.

[0061] Step S320: Perform coarse carrier synchronization on the filtered signal to determine the first signal.

[0062] The carrier synchronization process can be divided into two stages, carrier acquisition and carrier tracking, depending on the range of synchronization estimation. These can also be referred to as coarse carrier synchronization and fine carrier synchronization. After receiving a filtered signal within the frequency offset range, the terminal device uses coarse carrier synchronization technology to eliminate large frequency offsets in the filtered signal and determine the first signal.

[0063] In some embodiments, the communication signal is the PMBCH signal.

[0064] In some embodiments, the terminal device performs frequency band strength detection on the filtered signal within the bandwidth B of the communication signal to determine the coarse frequency offset range. Then, based on this range, coarse frequency offset compensation is performed on the filtered signal. To ensure that the compensated signal remains within the bandwidth B of the communication signal, narrowband filtering is applied. To increase the sampling rate, the filtered signal can be upsampled (e.g., by a factor of 4) to obtain the first signal X. i (0≤i≤L s L s = 4 × (B + 1) × T), where T is the sampling period of the communication signal. The bandwidth of the narrowband filter is related to the bandwidth B of the communication signal. For example, the bandwidth of the narrowband filter can be the width B of the communication signal plus a residual frequency offset. The residual frequency offset can be 1 kHz or several kHz; this application does not impose any restrictions on this. Narrowband filtering will be discussed in detail later. Figure 6 illustrate.

[0065] In some embodiments, since the bandwidth range of the filtered signal is [-B w / 2, B w [2] To enable parallel processing of filtered signals, the terminal device can segment the filtered signal based on the sampling period T of the communication signal, thereby obtaining at least one segmented signal. Then, a Fast Fourier Transform (FFT) is performed on the segmented signal to obtain the corresponding FFT data. Based on the FFT data, frequency band intensity detection can be performed on the segmented signal to determine its spectral energy. Finally, the coarse frequency offset range is determined based on the maximum spectral energy.

[0066] In some embodiments, if the number of segments is greater than or equal to two, then step S320 further includes concatenating the FFT data corresponding to the multiple segmented signals to obtain concatenated data, and performing frequency band strength detection on the concatenated data within the frequency band width corresponding to the concatenated data to determine the spectral energy within the frequency band width. For example, the following formula is used to calculate the spectral energy: In this embodiment, after frequency band filtering, the spectral information of all frequency bands can be combined through FFT operation. Here, i represents the total number of sampling points, 0 ≤ i ≤ L × N. FFT L is the number of segments, N FFT This represents the size of the FFT, i.e., the number of sampling points. K represents the number of points in the FFT occupied by the bandwidth B, and the frequency resolution of the FFT sampling points is f. s / N FFT f sWhere K is the sampling frequency, then K = CEILING(B × N) FFT / f s ). Here, CEILING means rounding up.

[0067] In step S320, the coarse frequency offset range can be determined based on the maximum spectral energy within the aforementioned frequency band width. For example, by shifting and calculating all the spectral energies within the frequency band width, the frequency band corresponding to the maximum spectral energy is found sequentially, and the frequency band corresponding to the maximum spectral energy is the coarse frequency offset range.

[0068] In some embodiments, the coarse frequency offset range includes integer multiples of the frequency offset ifo = -Δf max +m×f s / N FFT ,in, This represents the maximum spectral energy.

[0069] Based on the above processing, the terminal device can find the center frequency point corresponding to the maximum coarse frequency energy within bandwidth B, and simultaneously lock the coarse frequency offset and timing range, effectively shortening the network search time.

[0070] In some embodiments, it is assumed that the signal time slot length of the received communication signal is T. S The communication signal has a period of T0 and a sampling period of T. In some embodiments, step S320 further includes: calculating the number of points of the fast Fourier transform based on the bandwidth and sampling period of the communication signal, and calculating the number of times the fast Fourier transform is performed based on the time slot length, sampling period, and signal period of the communication signal.

[0071] In some embodiments, if the filtered signal is not segmented, then the size (i.e., the number of points) of the FFT1 obtained after performing an FFT on the filtered signal is N = T × f s =2T×(B+2×Δf) max ), the number of FFT1 CEILING(T0 / (TT) s In other embodiments, if a segmentation scheme is used, keeping the size of FFT1 constant, and if the number of segments is L, then the number of FFT1 operations is L × CEILING(T0 / (TT)). s If the filtered signal is divided into two segments, the resulting FFT2 signal after performing an FFT on these two segments has a coverage bandwidth of 2B, a size of 4B×L×T, and a number of iterations of (L-1)×CEILING(T0 / (L×TT)). s Similarly, we can obtain the magnitude and number of segments corresponding to dividing the filtered signal into 4 and 8 segments, respectively.

[0072] Table 1 provides an example, where B w = 2×(B+2×Δf)max )~128KHz, signal time slot length T S =12ms, the period of the received communication signal is T0=3.12s, and the maximum FFT size supported by FFT is 4096.

[0073] Table 1:

[0074] Bandwidth segmentation 1 2 4 8 Sampling period (ms) 16 32 64 128 FFT coverage bandwidth (KHz) 128 64 32 16 FFT size 4096 4096 4096 4096 FFT times 780 312 240 224

[0075] Based on computational complexity (including but not limited to FFT operations and frequency band strength detection) and the impact of bandwidth noise, the inventors of this application have discovered that a better and more satisfactory result can be obtained when the number of segments is determined to be 4. That is, the filtered signal is subjected to frequency band filtering by four filters to obtain four segmented signals. For this design, in step S320, after concatenating the FFT data of the four segmented signals, frequency band strength detection is performed on the concatenated data within the corresponding frequency band width to determine the spectral energy within the frequency band width.

[0076] In some embodiments, B = 16 kHz, T = 64 ms, L s =4362, the narrowband filter has a bandwidth of 17kHz.

[0077] Step S330: Perform timing fine synchronization processing on the first signal to determine the second signal.

[0078] After determining the first signal, the terminal device needs to perform symbol-based fine-time synchronization on the signal that has undergone coarse carrier frequency offset compensation (i.e., the first signal). For example, a cross-correlation symbol timing synchronization algorithm can be used, which involves cross-correlation between the received signal and the locally stored signal to determine the second signal.

[0079] In some embodiments, after coarse carrier synchronization processing of the filtered signal, the resulting first signal is locked within a reference signal with a bandwidth four times that of the narrowband filter bandwidth (e.g., (B+1) kHz) within a period T. To detect the optimal synchronization point, the terminal device performs correlation processing on the unique word (UW) reference signal based on the first signal, calculating the cyclic correlation coefficient of the UW reference signal. It can be understood that pilot shifting within the sampling period of the received communication signal reduces the computational load.

[0080] In some embodiments, the terminal device performs a Fast Fourier Transform (FFT) on the first signal and the UW reference signal of the communication signal to determine the target sampling point k. Using FFT-IFFT to implement shift correlation can reduce implementation complexity. To speed up processing, the first signal X is processed according to the target sampling point k. i Perform downsampling (e.g., 1 / 4 downsampling) to determine the second signal z i =Xk+4*i i = 0, 1, ..., TS LEN -1. Where TS LEN Let be the length of the second signal in the time domain.

[0081] In some embodiments, the terminal device will send the first signal X i Divide into two segments to obtain the first segment signal y. i The second segment signal z i .

[0082] in, Lu is the length of the UW reference signal (UW LEN ).

[0083] Then, the terminal device will send the first segment of signal y i The second segment signal z i Perform Fast Fourier Transform (FFT-IFFT) on the UW reference signal to determine the first sequence (including c). 1i and c 2i That is, c 1i =IFFT(FFT(u i )×FFT(y i )), c 2i =IFFT(FFT(u i )×FFT(z i The FFT size is N. FFT Satisfying not less than L s +3×Lu-1-N FFT The square root of N is denoted as N1. FFT .

[0084] in, i = 4 × UW LEN u i This indicates the signal obtained by inverting the sequence of the UW reference signal after sampling it four times.

[0085] Therefore, the first sequence is as follows:

[0086]

[0087] Finally, the terminal device finds the sampling point (index) corresponding to the maximum amplitude in the first sequence, that is... The above sampling points are used as target sampling points k in the timing synchronization algorithm.

[0088] In some embodiments, UW LEN =159, Lu=636, N FFT =4096, L s =4352, N1 FFT=4096, TS LEN =192.

[0089] Step S340: Perform frequency offset fine synchronization and phase synchronization based on the second signal.

[0090] In some embodiments, the terminal device performs fine frequency offset estimation based on the second signal, calculates the corresponding frequency offset estimate value, performs fine frequency offset compensation on the second signal, performs phase estimation based on the second signal, calculates the corresponding phase estimate value, and then performs phase compensation on the second signal.

[0091] In some embodiments, the precise frequency offset estimation is specifically implemented by: the terminal device calculating the correlation function between the second signal and the UW reference signal. i = 0, 1, ..., UW LEN -1. Where, UW * This represents the signal obtained after sequence inversion of the UW reference signal. Then, the terminal device performs FFT processing on the correlation function to obtain Z. i =FFT(y) i The FFT size is N. FFT Finally, the terminal device in Z i Find the sampling point k corresponding to the maximum amplitude in the sequence, and determine the frequency offset estimate based on sampling point k. The frequency offset estimate includes a fractional frequency offset.

[0092]

[0093] In some embodiments, phase estimation is specifically implemented as follows: after fine frequency offset compensation, the terminal device multiplies the second signal and the UW reference signal and then calculates the phase to obtain a phase estimate.

[0094] Next, the terminal device demodulates and decodes the signals after frequency offset compensation and phase offset compensation to obtain the Master Information Block (MIB) and System Information Block (SIB) information, and then performs the subsequent SIB decoding process.

[0095] In some embodiments, after decoding is completed, the decoded signal is re-encoded and modulated to generate a new signal, and then the FFT method is used again to estimate the residual frequency offset ffo2 of the new signal, which is then combined with the previously determined ifo and ffo to complete a higher-precision spectrum estimation.

[0096] In some embodiments, during signal reception, during the subsequent fine synchronization process of the maximum spectral energy in the spectral energy of the currently received signal, if the Cyclic Redundancy Check (CRC) of the decoding is correct, the frequency offset, timing information and signal strength of the current signal are saved.

[0097] Please see Figure 5 , Figure 5 This is a schematic diagram of the architecture of a carrier synchronization device provided in an embodiment of this application. (Reference) Figure 5 As shown, the carrier synchronization device 500 includes one or more of the following: an RFIC chip 501, a carrier synchronization module 502, an antenna 503, and a crystal oscillator 504, etc. These components can be connected via a bus or other means. The antenna 503 can be used to convert electromagnetic energy in a transmission line into electromagnetic waves in free space, or to convert electromagnetic waves in free space into electromagnetic energy in a transmission line. In this application, the antenna 503 may include one or more antennas, which can be used to receive communication signals from a satellite and transmit communication signals to the RFIC 501. Each antenna in the terminal device 202 can be used to cover one or more communication frequency bands, and different antennas can be multiplexed to improve antenna utilization.

[0098] A crystal oscillator 504 is an electronic circuit that generates a precise frequency electrical signal by utilizing the mechanical resonance of a vibrating crystal made of piezoelectric material, serving as a frequency reference. Crystal oscillators 504 include one or more of the following types: oven-controlled crystal oscillators (OCXO), temperature-compensated crystal oscillators (TCXO), voltage-controlled crystal oscillators (VCXO), and digitally compensated crystal oscillators (DCXO), etc.

[0099] The RFIC 501 is an integrated circuit chip used to process radio frequency (RF) signals. RF refers to the frequency range used in wireless communication, typically above several hundred kilohertz (kHz). The RFIC 501 can be used in applications such as wireless communication, radar, satellite communication, radio, wireless television, and wireless local area networks.

[0100] In this application, RFIC 501 is used to receive communication signals from antenna 503, which are radio frequency (RF) signals. After the communication signal is amplified by amplifier 5011, an electrical signal with a certain frequency from crystal oscillator 504 and synthesizer parameters from synthesizer are added to the communication signal. Then, the communication signal, which is an RF signal, is converted into a baseband signal by passing through first filter 5012, analog-to-digital converter, and digital filter.

[0101] In some embodiments, the bandwidth of the first filter 5012 is determined based on the bandwidth of the communication signal and the frequency offset between the terminal device 202 and the satellite 201. The bandwidth B of the first filter 5012 is... w =B + 2 × Δf max In this way, the terminal device 202 filters the communication signal from the satellite 201 through the first filter 5012 in RFIC 501 to obtain a filtered signal, so that the terminal device 202 can receive the signal within the frequency offset range at once and convert the radio frequency signal within the frequency offset range into a baseband signal.

[0102] The carrier synchronization module 502 includes one or more of the following: a carrier coarse synchronization module 5021, a timing fine synchronization module 5022, a frequency offset fine synchronization module 5023, a phase synchronization module 5024, and a decoding module 5025, etc. In conjunction with the carrier synchronization method implemented in this application, the carrier synchronization module 502 performs carrier coarse synchronization processing on the filtered signal using the carrier coarse synchronization module 5021 to determine a first signal; performs timing fine synchronization processing on the first signal using the timing fine synchronization module 5022 to determine a second signal; performs frequency offset fine synchronization and phase synchronization on the first signal using the frequency offset fine synchronization module 5023 and the phase synchronization module 5024 based on the second signal; and performs demapping and decoding on the synchronized signal using the decoding module 5025.

[0103] In some embodiments, the carrier synchronization module 502 determines the coarse frequency offset range by performing coarse carrier synchronization processing on the filtered signal through the carrier coarse synchronization module 5021, and determines the frequency offset estimate by performing fine frequency offset synchronization on the second signal through the frequency offset fine synchronization module 5023. The carrier synchronization module 502 determines the synthesizer parameters based on the coarse frequency offset range and the frequency offset estimate, and sends the synthesizer parameters to the RFIC 501. The RFIC 501 stores the synthesizer parameters in the synthesizer, so that they can be added to the next received communication signal from the satellite.

[0104] Please see Figure 6 , Figure 6 This is a schematic diagram illustrating an implementation scenario of the carrier coarse synchronization module 5021 according to an embodiment of this application. (Reference) Figure 6 In this embodiment, the carrier coarse synchronization module 5021 determines a segmentation scheme with 4 segments. Therefore, the filtered signal is multiplied by f0 and then filtered through low-pass filter 1 to obtain the first segment signal; the filtered signal is multiplied by f1 and then filtered through low-pass filter 2 to obtain the second segment signal; the filtered signal is multiplied by f2 and then filtered through low-pass filter 3 to obtain the third segment signal; and the filtered signal is multiplied by f3 and then filtered through low-pass filter 4 to obtain the fourth segment signal. Here, f0 = -48kHz, f1 = -16kHz, f2 = 16kHz, and f3 = 48kHz represent the center frequencies of the segments.

[0105] refer to Figure 6 As shown, the carrier coarse synchronization module 5021 performs FFT processing on the four segmented signals to obtain the FFT data corresponding to the segmented signals, and concatenates multiple FFT data sets. Frequency band strength detection is then performed on the concatenated FFT data to determine the coarse frequency offset range. In some embodiments, the carrier coarse synchronization module 5021 calculates the in-band power of the FFT data of the multiple segmented signals, where the in-band power includes the spectral energy of multiple frequency bands corresponding to the multiple segmented signals. The carrier coarse synchronization module 5021 determines the number of points corresponding to the maximum spectral energy value from the spectral energy of the multiple frequency bands. The coarse frequency offset range determined based on the above points includes ifo = -Δf max +m×f s / N FFT For example: Let N FFT =4096, f s =4×B, the bandwidth B of the communication signal occupies the number of points K of the FFT K=1024, therefore ifo=-50000+m×125 / 8.

[0106] The carrier coarse synchronization module 5021 compensates the filtered signal based on the ifo determined after maximum intensity detection, then performs narrowband filtering through a narrowband filter with a bandwidth of (B+1) kHz, and finally performs upsampling by 4 times to obtain the first signal X. i (0≤i≤L s L s = 4 × (B + 1) × T). In some embodiments, B = 16 kHz, T = 64 ms, L s =4362, the narrowband filter has a bandwidth of 17kHz.

[0107] Please see Figure 7 , Figure 7 This is a schematic diagram illustrating an implementation scenario of a timing precision synchronization module 5022 provided in an embodiment of this application. Through... Figure 6 The carrier coarse synchronization module 5021 shown performs carrier coarse synchronization processing on the filtered signal, and the determined first signal is locked within the sampling period T in a reference signal with a bandwidth four times that of the narrowband filter bandwidth (for example, (B+1) kHz). Figure 7 As shown, in order to detect the optimal synchronization point, the timing fine synchronization module 5022 performs timing fine synchronization processing on the first signal and the UW reference signal based on FFT-IFFT to determine the second signal.

[0108] In some embodiments, the timing synchronization module 5022 will use the UW reference signal (denoted as Uw) i , 0≤i≤UW LEN The signal UW was obtained by upsampling by 4 times.i , 0≤i≤4×UW LEN The signal UW obtained by upsampling by 4 times i Perform sequence reversal to obtain And for u i Perform FFT transformation to obtain FFT(u) i ).

[0109] The timing precision synchronization module 5022 synchronizes the first signal X. i Data segmentation is performed to obtain the first segment of signal y. i The second segment signal z i And for the first segment of signal y i The second segment signal z i Perform FFT transformations separately to obtain FFT(y) i ) and FFT(z i ).

[0110] The 5022 timing precision synchronization module will use FFT(u) i ) and FFT(y i After multiplying, perform IFFT to obtain c. 1i ; FFT(u i ) and FFT(z i After multiplying, perform IFFT to obtain c. 2i .

[0111] The 5022 timed precision synchronization module collects data according to c 1i and c 2i Determine the first sequence c i In the first sequence c i The point corresponding to the maximum amplitude is found; this point is the optimal point for timing synchronization, i.e., the target sampling point k. Finally, the timing precision synchronization module 5022 performs timing precision synchronization on the first signal X. i The second signal z is determined by performing 1 / 4 downsampling starting from the target sampling point k. i =X k+4*i i = 0, 1, ..., TS LEN -1.

[0112] Please see Figure 8 , Figure 8 This is a schematic diagram illustrating an implementation scenario of a frequency offset fine synchronization module 5023 provided in one embodiment of this application. (Reference) Figure 8 As shown, the frequency offset fine synchronization module 5023 will convert the second signal z i With UW reference signal After obtaining the relevant information i = 0, 1, ..., UW LEN -1, for y i Z is obtained by performing FFT transformation. i=FFT(y) i ).

[0113] The frequency offset precision synchronization module 5023 in sequence Z i Find the point corresponding to the maximum amplitude Based on this point, the residual frequency offset ffo in the frequency offset estimate can be determined, and frequency offset compensation can be performed on the second signal based on ffo.

[0114] Please see Figure 9 , Figure 9 This is a schematic diagram illustrating an implementation scenario of a phase synchronization module 5024 provided in an embodiment of this application. (Reference) Figure 9 As shown, the phase synchronization module 5024 will synchronize the second signal z i With UW reference signal The phase is estimated by multiplying the product by the dot product. Phase compensation is performed on the second signal based on the phase estimate.

[0115] The above combination Figures 3-9 The carrier synchronization method provided in the embodiments of this application is described in detail.

[0116] This application also provides a carrier synchronization apparatus for performing the carrier synchronization method provided in the embodiments of this application. Figure 5 This can serve as a schematic diagram of the carrier synchronization device of this application. It should be noted that the carrier synchronization device can be a terminal device, a chip (system) or other component or assembly disposed within the terminal device, or a device containing the terminal device; this application does not limit this. The foregoing description of the carrier synchronization method can be used to illustrate this carrier synchronization device.

[0117] This application also provides a terminal device. Please see [link to application]. Figure 10 , Figure 10 This is a simplified block diagram of a device 1000 suitable for implementing embodiments of this application. For example, a satellite network device 110 and / or a terminal device 101, etc., can be implemented by device 1000. As shown, device 1000 includes one or more processors 1010, one or more memories 1020 coupled to processor 1010, and one or more communication modules 1040 coupled to processor 1010.

[0118] The communication module 1040 is used for bidirectional communication. The communication module 1040 has at least one antenna to facilitate communication. The communication interface can represent any interface necessary for communication with other network elements.

[0119] Processor 1010 can be of any type suitable for a local technology network, and as a non-limiting example, can include one or more of the following: general-purpose computer, special-purpose computer, microprocessor, digital signal processor (DSP), and processor based on a multi-core processor architecture. Device 800 can have multiple processors, such as application-specific integrated circuit (ASIC) chips, which are timely driven to a clock that synchronizes with the main processor.

[0120] Memory 1020 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 1024, electrically programmable read-only memory (EPROM), flash memory, hard disk, optical disc (CD), digital video disc (DVD), and other magnetic and / or optical storage. Examples of volatile memories include, but are not limited to, random access memory (RAM) 1022 and other volatile memories that do not persist during power-off periods.

[0121] Computer program 1030 includes computer-executable instructions that are executed by the associated processor 1010. Program 1030 may be stored in ROM 1024. Processor 1010 may perform any appropriate actions and processes by loading program 1030 into RAM 1022.

[0122] The embodiments of this application can be implemented by program 1030, enabling device 1000 to execute the reference. Figure 3 Any process of the application discussed. Embodiments of this application may also be implemented by hardware or by a combination of software and hardware.

[0123] In some embodiments, program 1030 may be tangibly contained in a computer-readable medium, which may be contained in device 1000 (e.g., memory 1020) or other storage device accessible to device 1000. Device 1000 may load program 1030 from the computer-readable medium into RAM 1022 for execution. The computer-readable medium may include any type of tangible non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. Program 1030 is stored on the computer-readable medium.

[0124] Generally, the various embodiments of this application can be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while others may be implemented in firmware or software, which may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of this application are shown and described as block diagrams, flowcharts, or other graphical representations, it should be understood that, as non-limiting examples, the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof.

[0125] This application also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the aforementioned references. Figure 3 The method described in 300. Typically, a program module includes routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of a program module can be combined or separated among program modules as needed. The machine-executable instructions for a program module can be executed locally or in a distributed device. In a distributed device, the program module can reside in both local and remote storage media.

[0126] The program code used to perform the methods of this application can be written in any combination of one or more programming languages. This program code can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the program code is executed by the processor or controller, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The program code can be executed entirely on a machine, partially on a machine, partially on a remote machine, partially on a remote machine, or entirely on a remote machine or server as a standalone software package.

[0127] In the context of this application, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, etc.

[0128] Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable media can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or apparatuses, or any suitable combination thereof. More specific examples of computer-readable storage media include electrical connections having one or more wires, portable computer floppy disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable optical disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0129] Furthermore, although the operations are described in a specific order, this should not be construed as requiring that these operations be performed in the specific order or sequence shown, or that all of the operations shown be performed to obtain the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the foregoing discussion, these details should not be construed as limiting the scope of this application, but rather as descriptions of features specific to particular embodiments. Certain features described in the context of a single embodiment may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0130] Although this application has been described in language specific to structural features and / or methodological behavior, it should be understood that the application as defined in the appended claims is not necessarily limited to the specific features or behaviors described above. Rather, the specific features and actions described above are intended as exemplary forms for implementing the claims.

[0131] It should be fully understood that the use of personally identifiable information should comply with privacy policies and practices generally considered to meet or exceed industry or governmental requirements for protecting user privacy. In particular, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to the user.

Claims

1. A carrier synchronization method, characterized in that, Applied to a terminal device, the method includes: The communication signal from the network device is filtered by a first filter to obtain a filtered signal. The bandwidth of the first filter is determined based on the bandwidth of the communication signal and a first frequency offset range, which is determined based on the maximum frequency offset between the terminal device and the network device. Perform coarse carrier synchronization on the filtered signal to determine the first signal; The first signal is precisely synchronized during timing to determine the second signal; Frequency offset synchronization and phase synchronization are performed based on the second signal.

2. The method as described in claim 1, characterized in that, The step of performing carrier coarse synchronization on the filtered signal to determine the first signal includes: The filtered signal is subjected to frequency band intensity detection to determine the coarse frequency offset range; The filtered signal is subjected to coarse frequency offset processing based on the coarse frequency offset range to obtain the first signal.

3. The method as described in claim 2, characterized in that, The step of performing frequency band intensity detection on the filtered signal to determine the coarse frequency offset range includes: The filtered signal is segmented and filtered to determine at least one segmented signal; The frequency band intensity of the at least one segmented signal is detected by fast Fourier transform to determine the spectral energy of the at least one segmented signal; The coarse frequency offset range is determined based on the maximum spectral energy among the spectral energies of the at least one segmented signal.

4. The method as described in claim 3, characterized in that, Frequency band intensity detection of the at least one segmented signal using Fast Fourier Transform includes: The FFT data of multiple segmented signals are concatenated, and the spectral energy is calculated based on the concatenated data.

5. The method as described in claim 3, characterized in that, Also includes: The number of points of the Fast Fourier Transform is calculated based on the bandwidth and sampling period of the communication signal, and the number of times the Fast Fourier Transform is performed is calculated based on the time slot length, sampling period and signal period of the communication signal.

6. The method according to any one of claims 1 to 5, characterized in that, The step of performing precise timing synchronization on the first signal to determine the second signal includes: The target sampling point is determined by performing correlation processing on the unique word reference signals of the first signal and the communication signal; The first signal is downsampled based on the target sampling point to obtain the second signal.

7. The method as described in claim 6, characterized in that, The step of performing correlation processing on the unique word reference signals of the first signal and the communication signal to determine the target sampling point includes: Perform a fast Fourier forward-inverse transform on the correlation processed signals of the first signal and the communication signal to determine the first sequence; The sampling point corresponding to the maximum amplitude in the first sequence is taken as the target sampling point.

8. The method according to any one of claims 1 to 7, characterized in that, The step of performing frequency offset fine synchronization and phase synchronization of the first signal based on the second signal includes: Frequency offset estimation is performed on the second signal and the unique word reference signal of the communication signal to determine the frequency offset estimate value; Phase estimation is performed on the second signal and the unique word reference signal of the communication signal to determine the phase estimation value; Frequency offset compensation is performed on the first signal based on the frequency offset estimate, and phase compensation is performed on the first signal based on the phase estimate.

9. The method according to any one of claims 1 to 7, characterized in that, The filtered signal includes signals within the first frequency offset range.

10. A carrier synchronization device, characterized in that, include: Apparatus for performing the method according to any one of claims 1-9.

11. A terminal device, comprising: One or more processors; as well as One or more memories coupled to the one or more processors and storing instructions thereon, which, when executed individually or jointly by the one or more processors, cause the terminal device to perform the method of any one of claims 1-9.

12. A non-transitory computer-readable storage medium storing machine-executable instructions, which, when executed by one or more processors of the machine, cause the machine to perform the method of any one of claims 1-9.

13. A computer program product comprising instructions that, when executed individually or jointly by at least one processor of a computing device, cause the computing device to perform the method according to any one of claims 1-9.

14. A chip system for a computing device, the chip system comprising at least one processor configured to execute, individually or collectively, at least one memory-stored instruction of the computing device to cause the computing device to perform the method according to any one of claims 1-9.

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