Doppler frequency offset calculation method and device, initial access method and device, terminal and medium

Abstract

The invention provides a Doppler frequency offset calculation method and device, an initial access method and device, a terminal and a medium. The Doppler frequency offset calculation method is applied to a terminal, and the method comprises the following steps: receiving downlink synchronization information, the downlink synchronization information indicating first ephemeris information, and the first ephemeris information comprising first time information; and if the second ephemeris information exists, performing calculation based on the second ephemeris information and the first ephemeris information to determine a target Doppler frequency offset corresponding to a target moment, the second ephemeris information being information obtained before a time corresponding to the first moment information, and the target moment indicating a moment of sending an uplink signal to the network device. According to the invention, the Doppler frequency offset calculation error can be reduced, and the Doppler frequency offset compensation accuracy is improved.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a Doppler frequency deviation calculation method, an initial access method, a device, a terminal and a medium. Background Art

[0002] In NTN (Non-Terrestrial Networks) communications, the network-side device needs to complete the initial access of the user-side device through beam scanning. During the initial access process, the user-side device will send an uplink signal to the network-side device to complete the initial access.

[0003] Since in NIN, the network side equipment will move around the earth, causing a large Doppler shift, when sending an uplink signal to the network side, Doppler frequency offset compensation is generally performed first, and then the uplink signal is sent to perform uplink frequency synchronization. The Doppler frequency offset is generally calculated by the ephemeris information sent by the network side equipment. There is a time difference between the time when the network side equipment sends the ephemeris information and the time when the user side equipment sends the uplink signal. The ephemeris information sent by the network side equipment and the actual ephemeris information corresponding to the time when the user side equipment sends the uplink signal may be different, resulting in errors in the calculation of the Doppler frequency offset, and the accuracy of the Doppler frequency offset compensation is not high, and thus the uplink frequency synchronization cannot be guaranteed. Summary of the invention

[0004] The present application provides a Doppler frequency offset calculation method, an initial access method, a device, a terminal and a medium, which can reduce the error of Doppler frequency offset calculation and improve the accuracy of Doppler frequency offset compensation.

[0005] In a first aspect, a Doppler frequency shift calculation method is proposed, which is applied to a terminal, and the method includes:

[0006] receiving downlink synchronization information, where the downlink synchronization information indicates first ephemeris information, and the first ephemeris information includes first time information;

[0007] If there is second ephemeris information, a calculation is performed based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time, wherein the second ephemeris information is information obtained before the time corresponding to the first time information, and the target time indicates the time when an uplink signal is sent to the network device.

[0008] In an implementable manner, the performing calculation based on the second ephemeris information and the first ephemeris information to determine a target Doppler frequency deviation corresponding to a target time includes:

[0009] Performing interpolation calculation on the second ephemeris information and the first ephemeris information to determine first target ephemeris information at the target time;

[0010] The target Doppler frequency offset is determined based on the first target ephemeris information.

[0011] In an implementable manner, the number of the second ephemeris information is at least one, and different second ephemeris information corresponds to different second time information; and the interpolation calculation of the second ephemeris information and the first ephemeris information to determine the first target ephemeris information at the target time includes:

[0012] On the time axis, if the time interval between the second moment information of two adjacent second ephemeris information of the target is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the two adjacent second ephemeris information of the target, and / or, if the time interval between the target second moment information of the target second ephemeris information adjacent to the first ephemeris information and the first moment information is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the target second ephemeris information and the first ephemeris information;

[0013] An interpolation calculation is performed based on the first ephemeris information, the second ephemeris information and the third ephemeris information to determine first target ephemeris information at the target time.

[0014] In an implementable manner, the performing calculation based on the second ephemeris information and the first ephemeris information to determine a target Doppler frequency deviation corresponding to a target time includes:

[0015] Determining a first Doppler frequency offset corresponding to the first ephemeris information;

[0016] Determining a second Doppler frequency offset corresponding to the second ephemeris information;

[0017] An interpolation calculation is performed on the first Doppler frequency offset and the second Doppler frequency offset to obtain the target Doppler frequency offset.

[0018] In an implementable manner, the number of the second Doppler frequency offsets is at least one, and different Doppler frequency offsets correspond to different second time information; and the interpolation calculation of the first Doppler frequency offset and the second Doppler frequency offset to obtain the target Doppler frequency offset includes:

[0019] On the time axis, if the time interval between the second moment information of two adjacent second Doppler frequency deviations of the target is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the two adjacent second Doppler frequency deviations of the target, and / or, if the time interval between the target second moment information of the target second Doppler frequency deviation adjacent to the first Doppler frequency deviation and the first moment information is greater than the preset interpolation time interval, at least one third Doppler frequency deviation is interpolated between the target second Doppler frequency deviation and the first Doppler frequency deviation;

[0020] An interpolation calculation is performed based on the first Doppler frequency offset, the second Doppler frequency offset, and the third Doppler frequency offset to determine the Doppler frequency offset at the target time.

[0021] In an implementable manner, the first ephemeris information includes first position information and first speed information of the network device at a time corresponding to the first moment information; if there is no second ephemeris information, the method further includes:

[0022] Determine a target time difference between the target time and a time corresponding to the first time information;

[0023] Determine second position information corresponding to the target time according to the first position information, the first speed information and the target time difference, wherein there is a linear relationship between the second position information and the target time difference;

[0024] The second position information, the time information corresponding to the target time, and the first speed information are used as second target ephemeris information, and the target Doppler frequency deviation is determined based on the second target ephemeris information.

[0025] In an implementable manner, before performing calculation based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time, the method further includes:

[0026] Determine initial ephemeris information before the time corresponding to the first moment information, wherein the initial ephemeris information includes initial moment information;

[0027] The initial ephemeris information in which the difference between the time corresponding to the initial time information in the initial ephemeris information and the time corresponding to the first time information is within a preset value range is used as the second ephemeris information.

[0028] In a second aspect, an initial access method is proposed, which is applied to a terminal, and the method includes:

[0029] Obtaining a target Doppler frequency deviation at the target time determined as in the first aspect;

[0030] The uplink signal is subjected to frequency deviation compensation processing based on the target Doppler frequency deviation, and the uplink signal subjected to the frequency deviation processing is sent to the network device at the target time.

[0031] In a third aspect, a Doppler frequency deviation calculation device is proposed, which is applied to a terminal, and the device includes:

[0032] A receiving module, configured to receive downlink synchronization information, wherein the downlink synchronization information indicates first ephemeris information, and the first ephemeris information includes first time information;

[0033] A processing module is used to calculate the second ephemeris information and the first ephemeris information if there is any, so as to determine the target Doppler frequency deviation corresponding to the target time, wherein the second ephemeris information is information obtained before the time corresponding to the first time information, and the target time indicates the time when the uplink signal is sent to the network device.

[0034] In a fourth aspect, the present application provides a terminal, comprising: a processor, and a memory communicatively connected to the processor;

[0035] The memory stores computer-executable instructions;

[0036] The processor executes the computer-executable instructions stored in the memory to implement the Doppler frequency shift calculation method as described in the first aspect or the initial access method as described in the second aspect.

[0037] In a fifth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer execution instructions, and when the computer execution instructions are executed by a processor, they are used to implement the Doppler frequency deviation calculation method as described in the first aspect or the initial access method as described in the second aspect.

[0038] In a sixth aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the Doppler frequency shift calculation method as described in the first aspect or the initial access method as described in the second aspect.

[0039] The Doppler frequency deviation calculation method, initial access method, device, terminal and medium provided by the present application do not directly calculate the Doppler frequency deviation through the first ephemeris information after receiving the downlink synchronization information indicating the first ephemeris information, but determine whether there is second ephemeris information before the time corresponding to the first moment information. If so, the target Doppler frequency deviation at the target moment can be obtained by calculation through the second ephemeris information and the first ephemeris information. This method takes into account the time delay between the moment of receiving the downlink synchronization information and the moment of sending the uplink signal during the initial access process, accurately calculates the Doppler frequency deviation at the target moment through the first ephemeris information and the second ephemeris information located before the moment of receiving the first ephemeris information, reduces the error of Doppler frequency deviation calculation, improves the accuracy of Doppler frequency deviation compensation, and thus ensures uplink frequency synchronization. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0041] Figure 1 is an initial access flow chart shown in an exemplary embodiment;

[0042] Figure 2 is a structural diagram of a communication system shown in an exemplary embodiment;

[0043] Figure 3 is a flow chart of a Doppler frequency deviation calculation method shown in an exemplary embodiment;

[0044] Figure 4 is an initial access flow chart shown in another exemplary embodiment;

[0045] Figure 5 is a flow chart of a Doppler frequency deviation calculation method shown in another exemplary embodiment;

[0046] Figure 6 is a flowchart of obtaining first target ephemeris information shown in an exemplary embodiment;

[0047] Figure 7 is a flow chart of a Doppler frequency deviation calculation method shown in another exemplary embodiment;

[0048] Figure 8 is a flow chart of a Doppler frequency deviation calculation method shown in another exemplary embodiment;

[0049] Fig. 9 is a diagram showing a difference between a real Doppler frequency shift and a target Doppler frequency shift according to an exemplary embodiment;

[0050] Fig.10 is a structural diagram of a Doppler frequency deviation calculation device shown in an exemplary embodiment;

[0051] Fig.11 It is a schematic diagram of the structure of a terminal shown in an exemplary embodiment.

[0052] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0053] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0054] In NTN (Non-Terrestrial Networks)-based communications, when the network-side device (such as a satellite) is unaware of the location of the user-side device, it is necessary to complete the initial access of the user-side device through beam scanning, such as Figure 1 As shown, the process of establishing initial access by the user side device mainly includes the following steps:

[0055] S1. The user-side device overscans each beam to obtain the optimal beam.

[0056] S2. The user-side device detects and parses the SSB (synchronization signal and broadcast signal) sent by the network-side device on the optimal beam to obtain the ephemeris information. The SSB contains the PBCH (Physical Broadcast Channel), which carries the relevant information for downlink synchronization. In satellite communications, the ephemeris information will be sent to the user-side device along with the PBCH, and the user-side device will parse the ephemeris information.

[0057] S3. The initial beam will complete the discovery of all user-side devices through search. After completing the initial access, the user-side device initiates a random access request PRACH (Physical Random Access Channel) and uploads the beam position index and service requirements. The network-side device satellite receives the random access request and schedules the corresponding service beam for communication; among them, the initial beam search scheme can include exhaustive, iterative, unilateral search, etc., and no specific restrictions are made here.

[0058] In this process, the network side equipment will have problems such as large transmission delay, high Doppler frequency deviation, large cell coverage radius, and cell "movement" due to its high position, large beam coverage range, and fast movement speed of non-geostationary orbit satellites. In this initial access method, the ephemeris information is parsed based on the downlink synchronization information (SSB / PBCH) received by the user side device, and the downlink synchronization and Doppler frequency deviation are calculated directly through the ephemeris information. The uplink signal (random access request) sent by the user side device is compensated for the frequency deviation through the Doppler frequency deviation.

[0059] However, the ephemeris information obtained by parsing the downlink synchronization information received by the user-side device is the ephemeris information when the network-side device sends the downlink synchronization information. At the time of initial access, there is a delay caused by the initial beam search and a delay caused by the path transmission between the downlink synchronization information sent from the network-side device to the user-side device. These delays will affect the real-time performance of the downlink synchronization information. If the Doppler frequency offset is calculated directly through the ephemeris information, the calculated Doppler frequency offset has a numerical value that is not accurate enough, resulting in inaccurate Doppler frequency offset compensation; and the delay caused by the initial beam search is greatly related to the beam-customized scanning scheme and the corresponding number of cells. If the corresponding ephemeris information is used to compensate for the Doppler frequency offset and send an uplink signal when the initial beam is directly used to scan the cell, the delay caused is different according to the initial beam search scheme and the number of cells, which further leads to large errors in Doppler frequency offset calculation and inaccurate Doppler frequency offset compensation.

[0060] Based on this, the embodiments of the present application propose a Doppler frequency deviation calculation method, an initial access method, a device, a terminal and a medium. After receiving the first ephemeris information, the second ephemeris information before the first ephemeris information acquisition time is obtained, and the target Doppler frequency deviation at the target time is obtained by calculating the currently received first ephemeris information and the second ephemeris information, and according to the relationship between the ephemeris information and the Doppler frequency deviation, the error of the Doppler frequency deviation can be reduced, the accuracy of the Doppler frequency deviation compensation can be improved, and the uplink frequency synchronization can be ensured.

[0061] To facilitate understanding of the embodiments of the present application, first Figure 2 The communication system applicable to the embodiment of the present application is described in detail. Figure 2 As shown, the communication system 200 may include at least one network device, such as Figure 2 The network device 210 shown; the communication system 200 may also include at least one terminal, such as Figure 2The terminal 220 shown in the figure. The terminal 220 can be mobile or fixed. The network device 210 is a device that can communicate with the terminal 220 via a wireless link, such as a base station or a base station controller. Each network device can provide communication coverage for a specific geographical area and can communicate with terminals located in the coverage area (cell).

[0062] It should be noted that the technical solutions of the embodiments of the present disclosure can be applied to various communication systems, such as long term evolution (LTE) system, fifth generation (5G) mobile communication system, 5G new radio (NR) system, or other future new mobile communication systems.

[0063] In the embodiment of the present application, the network device 210 may include a non-terrestrial network device, such as a satellite. The satellite can be regarded as a mobile network device, and no specific limitation is made here.

[0064] The network device 210 in the embodiment of the present disclosure is an entity on the network side for transmitting or receiving signals, and the network device can be a network side device. For example, the network device 210 can be an evolved NodeB (eNB), a transmission point (TRP), a next generation NodeB (gNB) in an NR system, a base station in other future mobile communication systems, or an access node in a wireless fidelity (WiFi) system. The embodiments of the present disclosure do not limit the specific technology and specific device form adopted by the network device.

[0065] The network device provided by the embodiments of the present disclosure may be composed of a centralized unit (CU) and a distributed unit (DU), wherein the CU may also be referred to as a control unit. The CU-DU structure may be used to split the protocol layer of a network device, such as a base station, with some functions of the protocol layer being centrally controlled by the CU, and the remaining part or all of the functions of the protocol layer being distributed in the DU, and the DU being centrally controlled by the CU.

[0066] The terminal 220 in the embodiment of the present disclosure is an entity on the user side for receiving or transmitting signals, such as a mobile phone. The terminal may also be referred to as a terminal, user equipment (UE), mobile station (MS), mobile terminal (MT), user side device, etc. The terminal may be a car with communication function, a smart car, a mobile phone, a wearable device, a tablet computer (Pad), a computer with wireless transceiver function, a virtual reality (VR) terminal, an augmented reality (AR) terminal, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc.

[0067] In some embodiments, the network device 210 sends downlink synchronization information, and the terminal receives the downlink synchronization information, the downlink synchronization information indicates first ephemeris information, and the first ephemeris information includes first time information; if there is second ephemeris information, a calculation is performed based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time, the second ephemeris information is information obtained before the time corresponding to the first time information, and the target time indicates the time when the uplink signal is sent to the network device, thereby improving the accuracy of the Doppler frequency deviation.

[0068] The embodiments of the present disclosure do not limit the specific technology and specific device form adopted by the terminal.

[0069] It can be understood that the communication system described in the embodiment of the present disclosure is for the purpose of more clearly illustrating the technical solution of the embodiment of the present disclosure, and does not constitute a limitation on the technical solution provided by the embodiment of the present disclosure. A person skilled in the art can know that with the evolution of the system architecture and the emergence of new business scenarios, the technical solution provided by the embodiment of the present disclosure is also applicable to similar technical problems.

[0070] The Doppler frequency deviation calculation method and device provided by the present disclosure are described in detail below with reference to the accompanying drawings.

[0071] Figure 3: is a flow chart of a Doppler frequency deviation calculation method provided by an embodiment of the present disclosure, and the method is executed by a terminal. The Doppler frequency deviation calculation method in this embodiment can be applied to a terminal, such as a mobile phone or a tablet with mobile communication function, a smart watch, etc., and the method includes:

[0072] S301. Receive downlink synchronization information, where the downlink synchronization information indicates first ephemeris information, and the first ephemeris information includes first time information.

[0073] In some embodiments, the network device sends downlink synchronization information, the downlink synchronization information indicates the first ephemeris information when the network device sends the downlink synchronization information, the first ephemeris information includes first time information, and the first time information corresponds to the time when the network device sends the downlink synchronization information.

[0074] In some embodiments, the downlink synchronization information includes first ephemeris information.

[0075] In some embodiments, the downlink synchronization information may be an SSB sent by a network device, wherein the SSB includes a PBCH.

[0076] In some embodiments, the first ephemeris information includes orbital parameters of the network device; optionally, the first ephemeris information includes one or more of position information, speed information, and orbital shape information of the network device.

[0077] In some embodiments, the first ephemeris information includes first time information, position information of the network device at a time corresponding to the first time information, and speed information.

[0078] S302. If there is second ephemeris information, calculation is performed based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time. The second ephemeris information is information obtained before the time corresponding to the first time information. The target time indicates the time when an uplink signal is sent to the network device.

[0079] In some embodiments, Figure 4 As shown, the network device sends downlink synchronization information at time T0, then the time corresponding to the first time information is the Toe time, and the terminal receives the downlink synchronization information at time T0+T_delay. The duration corresponding to T_delay is the transmission delay caused by the distance between the network device and the terminal, that is, the path delay. After the initial beam search is completed, the terminal sends an uplink signal at time T1+T_delay. The T1+T_delay time is the target time, and the network device should receive the uplink signal at time T1+2T_delay.

[0080] In some embodiments, the first ephemeris information is the ephemeris information at time T0, and Doppler frequency offset compensation for the uplink signal requires the Doppler frequency offset at time T1+T_delay. Directly calculating the target Doppler frequency offset corresponding to the target time through the first ephemeris information has the problem of too large error.

[0081] For example, for low-orbit network equipment, the path delay is about 10ms (milliseconds). T1-T0 represents the time required for a round of beam search. T1-T0 is related to the number of cells determined by the orbital parameters, antenna pointing, and ground station location information of the network equipment. The cell location determines the coverage and pointing of the beam. The cell dwell time represents the time the antenna beam spends on the target cell. Taking radar as an example, the cell dwell time T D The calculation formula is as follows:

[0082]

[0083] Among them, θ AZ Indicates the horizontal beam width of the antenna, n indicates the rotation speed of the antenna (assuming it rotates once per minute, 60 means 60 seconds). Assuming that the beam width of a parabolic antenna is 1.6°, then the full circle of 360° is divided into 360° / 1.6°=225 different directions, corresponding to 225 cell positions. Assuming that the residence time of each cell is 22ms, the period of beam search is T1-T0=225*22ms=4950ms=4.95s. It can be seen that there is a certain time in the beam search, and after the beam search is completed, the ephemeris information (position information, speed information) corresponding to the network device at that time is compared with the first satellite. The ephemeris information has changed significantly. After the terminal receives the downlink synchronization information and obtains the first ephemeris information, if the Doppler frequency deviation is calculated according to the first ephemeris information, that is, the target Doppler frequency deviation corresponding to the target time is calculated using the first ephemeris information T0 to compensate for the frequency deviation, the delay caused by the beam search and the transmission delay between the satellite and the ground are not taken into account, resulting in errors in the calculated Doppler frequency deviation, causing signal distortion and affecting the performance of the communication system; at the same time, due to the existence of the Doppler frequency deviation error, the terminal needs a higher gain and a more complex algorithm to compensate for the impact caused by the frequency deviation, thereby increasing the complexity and power consumption of the terminal signal processing.

[0084] In this embodiment, it can be detected whether the terminal has the second ephemeris information. If the second ephemeris information exists, calculation is performed based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time.

[0085] In this embodiment, the second ephemeris information is obtained by the terminal before receiving the downlink synchronization information indicating the first ephemeris information.

[0086] In some embodiments, the terminal receives historical downlink synchronization information, which indicates second ephemeris information. The terminal calculates the Doppler frequency deviation of the historical target time based on the second ephemeris information indicated by the historical downlink synchronization information, and sends a historical uplink signal according to the Doppler frequency deviation of the historical target time, but the initial access corresponding to the historical downlink synchronization information fails.

[0087] In some embodiments, the network device continuously sends downlink synchronization information. For one downlink synchronization information, the initial access of the downlink synchronization information sent before the downlink synchronization information fails. The downlink synchronization information with the initial access failure is regarded as the historical downlink synchronization information, and the ephemeris information corresponding to the downlink synchronization information identified by the access corresponds to the second ephemeris information.

[0088] In some embodiments, the number of second ephemeris information corresponding to the second ephemeris information is at least one, each second ephemeris information includes corresponding second time information, and the time corresponding to the second time information is the time when the historical downlink synchronization information indicating the second ephemeris information was sent.

[0089] On the time axis, the moment corresponding to the first moment information is located after the moment corresponding to the second moment information.

[0090] In some embodiments, the calculation based on the second ephemeris information and the first ephemeris information can be performed on the time axis, interpolating the second ephemeris information and the first ephemeris information, predicting and determining the ephemeris information at the target time, and determining the target Doppler frequency deviation at the target time through the ephemeris information at the target time; or it can be performed by obtaining a first Doppler frequency deviation corresponding to the first ephemeris information, obtaining a second Doppler frequency deviation corresponding to the second ephemeris information, calculating the second Doppler frequency deviation and the first Doppler frequency deviation on the time axis, and predicting the target Doppler frequency deviation at the target time.

[0091] In some embodiments, if the second ephemeris information does not exist, the target Doppler frequency offset may be determined according to a preset relationship.

[0092] In some embodiments, the first ephemeris information includes the first position information and first speed information of the network device at the time corresponding to the first moment information, determines the target moment difference between the target moment and the moment corresponding to the first moment information, determines the second position information corresponding to the target moment according to the first position information, the first speed information and the target moment difference, and there is a linear relationship between the second position information and the target moment difference; uses the second position information, the moment information corresponding to the target moment and the first speed information as the second target ephemeris information, and determines the target Doppler frequency deviation based on the second target ephemeris information.

[0093] In an embodiment of the present application, after receiving the downlink synchronization information indicating the first ephemeris information, the Doppler frequency deviation is not calculated directly through the first ephemeris information, but it is determined whether there is a second ephemeris information before the time corresponding to the first moment information. If there is, the target Doppler frequency deviation at the target moment can be calculated through the second ephemeris information and the first ephemeris information. This method takes into account the time delay between the time of receiving the downlink synchronization information and the time of sending the uplink signal during the initial access process, and accurately calculates the Doppler frequency deviation at the target moment through the first ephemeris information and the second ephemeris information located before the time of receiving the first ephemeris information, thereby reducing the error of the Doppler frequency deviation calculation, improving the accuracy of the Doppler frequency deviation compensation, and thus ensuring uplink frequency synchronization. For example, interpolation calculation can be performed, taking into account the transmission delay and beam search delay during initial access, and accurately calculating the Doppler frequency deviation at the target moment according to the first ephemeris information and the second ephemeris information.

[0094] Figure 5 is a flowchart of a Doppler frequency shift calculation method shown in another exemplary embodiment, the method is executed by a terminal, Figure 5 propose Figure 3 A method for calculating a target Doppler frequency deviation in step S302, the method for calculating a target Doppler frequency deviation comprising:

[0095] S501: Perform interpolation calculation on the second ephemeris information and the first ephemeris information to determine the first target ephemeris information at the target time.

[0096] In some embodiments, the second ephemeris information and the first ephemeris information are interpolated to predict the first target ephemeris information at the target time, and the Doppler frequency deviation at the target time can be subsequently calculated using the first target ephemeris information, thereby improving the accuracy of the target Doppler frequency deviation.

[0097] In some embodiments, the network device continuously sends downlink synchronization information, and the terminal receives the downlink synchronization information for initial access. During each initial access, the ephemeris information corresponding to each downlink synchronization information is stored.

[0098] For the first ephemeris information corresponding to a downlink synchronization information, the initial ephemeris information before the time corresponding to the first moment information can be determined. On the time axis, the time of the initial moment information corresponding to the initial ephemeris information is before the time corresponding to the first moment information.

[0099] It can be understood that the initial ephemeris information can be the ephemeris information corresponding to the downlink synchronization information of the initial access failure, or the ephemeris information corresponding to the downlink synchronization information of the initial access success. If it is the ephemeris information corresponding to the downlink synchronization information of the initial access success, the initial moment information corresponding to the initial ephemeris information should be far away from the first moment information corresponding to the time, such as the initial access between the last network device restart and the terminal.

[0100] In some embodiments, the initial ephemeris information in which the difference between the moment corresponding to the initial moment information and the moment corresponding to the first moment information is within a preset numerical range is used as the second ephemeris information, thereby reducing the interference of the initial ephemeris information that is far away from the moment corresponding to the first ephemeris information on subsequent interpolation calculations, thereby improving the efficiency and accuracy of the interpolation calculations.

[0101] The number of the second ephemeris information is at least one, and the second ephemeris information and the second time information corresponding to the second ephemeris information are used as known nodes, and the first target ephemeris information is obtained by extrapolating the second ephemeris information and the first ephemeris information.

[0102] In some embodiments, on the time axis, the second ephemeris information corresponding to the second moment information and the first ephemeris information corresponding to the first moment are determined, and the first target ephemeris information corresponding to the target moment can be obtained through interpolation calculation.

[0103] In some embodiments, the interpolation calculation method may include but is not limited to Lagrange interpolation algorithm, Newton interpolation algorithm, trigonometric function interpolation algorithm, generalized extension approximation method and other algorithms that can be used for interpolation and their corresponding improved algorithms.

[0104] Taking the Lagrangian interpolation algorithm as an example, according to the Lagrangian interpolation algorithm, the first ephemeris information of the target time is obtained based on extrapolation. The Lagrangian interpolation algorithm is as follows:

[0105]

[0106] Where n represents the point of n-order interpolation, corresponding to the total number of first ephemeris information and second ephemeris information, i represents the i-th point, j represents the j-th point, i and j can be the points corresponding to the first ephemeris information or the points corresponding to the second ephemeris information, L i (x) represents the calculation parameter, x represents the point of the first target ephemeris information corresponding to the target time, f(x) is the first ephemeris information at the target time, f(x) i ) represents the ephemeris information corresponding to each i-th point, which can be the first ephemeris information or the second ephemeris information.

[0107] As in some embodiments, Figure 6In the flowchart for obtaining the first target ephemeris information shown, PVT_T0 is the first ephemeris information corresponding to the first moment information at time T0, PVT_T0-1T, PVT_T0-2T, PVT_T0-3T, and PVT_T0-4T are the second ephemeris information at time T0-1T, time T0-2T, time T0-3T, and time T0-4T respectively. The first target ephemeris information PVT_T0+1T at the target time T0+1T can be calculated through PVT_T0, PVT_T0-1T, PVT_T0-2T, PVT_T0-3T, and PVT_T0-4T.

[0108] Understandably, Figure 6 The preset interpolation time interval shown in is T. In other embodiments, the interpolation time interval may be other values, and the time interval between two adjacent ephemeris information in time may be the same or different.

[0109] In some embodiments, the first target ephemeris information includes the predicted location information and speed information of the network device at the target time.

[0110] In some embodiments, the time interval between the first ephemeris information and the second ephemeris information on the time axis can be determined to determine whether interpolation is required between two adjacent ephemeris information, thereby obtaining more ephemeris information for predicting the first target ephemeris information.

[0111] Assume that there is a low-orbit network device that can cover 400 cells, and its initial beam stays in each cell for 8ms. Then, according to calculation, the time required for the initial beam to search all cells is:

[0112] T2 = 400 * 8ms = 3200ms = 3.2s

[0113] According to the calculation results, the delay of the initial beam search for all cells returning to the original cell is 3.2s (seconds). According to Kepler's third law, the movement speed of low-orbit network equipment is about 7.2km / s (kilometers per second). Therefore, after the initial beam search, the position of the satellite has changed significantly. Therefore, it is necessary to predict the PVT ephemeris information of the satellite position information during the initial access process.

[0114] If the time interval between two adjacent ephemeris information in the first ephemeris information and the second ephemeris information is greater than the preset interpolation time interval, ephemeris data within a smaller time interval can be obtained by interpolation. For example, if the time interval between two adjacent ephemeris information in the first ephemeris information and the second ephemeris information is 3.2s, and the preset interpolation time interval is 1.6s, more accurate and rich ephemeris information can be obtained by further interpolation for predicting the first target ephemeris information.

[0115] In some embodiments, the number of second ephemeris information is at least one, and different second ephemeris information corresponds to different second moment information; on the time axis, if the time interval between the second moment information of two adjacent target second ephemeris information is greater than a preset interpolation time interval, at least one third ephemeris information is interpolated between the two adjacent target second ephemeris information, and / or, if the time interval between the target second moment information and the first moment information of the target second ephemeris information adjacent to the first ephemeris information is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the target second ephemeris information and the first ephemeris information; interpolation calculation is performed based on the first ephemeris information, the second ephemeris information and the third ephemeris information to determine the first target ephemeris information at the target moment.

[0116] In some embodiments, if the number of second ephemeris information is one, the second ephemeris information machine is the target second ephemeris information. If the time interval between the target second moment information of the target second ephemeris information and the first moment information is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the target second ephemeris information and the first ephemeris information.

[0117] In some embodiments, the number of first ephemeris information is at least two, and the second ephemeris information closest to the first ephemeris information on the time axis is used as the target second ephemeris information. If the time interval between the target second moment information and the first moment information of the target second ephemeris information is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the target second ephemeris information and the first ephemeris information. At the same time, it can be determined on the time axis whether there is a time interval between two adjacent second ephemeris information greater than the preset difference time interval.

[0118] If the time interval between two adjacent second ephemeris information is greater than the preset difference time interval, the two adjacent second ephemeris information are used as target two adjacent second ephemeris information, and at least one third ephemeris information is interpolated between the target two adjacent second ephemeris information.

[0119] In some embodiments, on the time axis, a time interval between two adjacent ephemeris information among the first ephemeris information, the second ephemeris information and the third ephemeris information is less than a preset interpolation time interval.

[0120] In this embodiment, by interpolating the third ephemeris information between the first ephemeris information and the second ephemeris information, the amount of ephemeris information used to predict the first target ephemeris information is increased, thereby improving the accuracy of subsequent prediction of the first target ephemeris information.

[0121] S502: Determine a target Doppler frequency deviation based on first target ephemeris information.

[0122] After obtaining the first target ephemeris information, the target Doppler frequency deviation can be calculated through the first target ephemeris information. For example, the target Doppler frequency deviation can be determined by the location information, speed information of the network device corresponding to the first target ephemeris information and the location information of the terminal. No specific restrictions are imposed herein on the method of determining the target Doppler frequency deviation based on the first target ephemeris information.

[0123] In an embodiment of the present application, a method for calculating a target Doppler frequency deviation is disclosed. The first target ephemeris information is determined by interpolating the first ephemeris information and the second ephemeris information. The first target ephemeris information is the predicted position information and speed information of the network device at the target time. The target Doppler frequency deviation at the target time can be accurately obtained by calculating the first target ephemeris information. This method can reduce the error caused by the delay to the Doppler frequency deviation.

[0124] Figure 7 is a flow chart of another Doppler frequency deviation calculation method provided by an embodiment of the present disclosure, the method is executed by a terminal, Figure 7 propose Figure 3 Another method for calculating the target Doppler frequency offset in step S302 of the embodiment of the present invention comprises:

[0125] S701: Determine a first Doppler frequency offset corresponding to first ephemeris information.

[0126] In this embodiment, the first Doppler frequency offset corresponding to the first ephemeris information may be calculated. The first Doppler frequency offset at this time is the Doppler frequency offset at the time corresponding to the first time information.

[0127] S702: Determine a second Doppler frequency offset corresponding to second ephemeris information.

[0128] In some embodiments, the method for determining the second ephemeris information by using the initial ephemeris information can refer to the method described above, which will not be described in detail here.

[0129] The number of second ephemeris information corresponding to the second ephemeris information is one or more. For each second ephemeris information, the corresponding second Doppler frequency offset is calculated. The second Doppler frequency offset is the Doppler frequency offset at the moment corresponding to the second moment information, that is, the second Doppler frequency offset corresponds to the second moment information.

[0130] S703: Perform interpolation calculation on the first Doppler frequency offset and the second Doppler frequency offset to obtain a target Doppler frequency offset.

[0131] In this embodiment, the interpolation calculation method for the first Doppler frequency deviation and the second Doppler frequency deviation can refer to the interpolation calculation method for the second ephemeris information and the first ephemeris information. Different from this, in this embodiment, the time axis is used as a known point to perform interpolation calculation to determine the target Doppler frequency deviation at the target time.

[0132] In some embodiments, on the time axis, the time interval between the first Doppler frequency offset and the second Doppler frequency offset on the time axis can be determined to determine whether interpolation is required between two adjacent Doppler frequency offsets, thereby obtaining more Doppler frequency offsets for predicting the target Doppler frequency offset.

[0133] In some embodiments, the number of second Doppler frequency deviations is at least one, and different Doppler frequency deviations correspond to different second moment information; on the time axis, if the time interval between the second moment information of two adjacent second Doppler frequency deviations of the target is greater than a preset interpolation time interval, at least one third ephemeris information is interpolated between the two adjacent second Doppler frequency deviations of the target, and / or, if the time interval between the target second moment information and the first moment information of a target second Doppler frequency deviation adjacent to the first Doppler frequency deviation is greater than a preset interpolation time interval, at least one third Doppler frequency deviation is interpolated between the target second Doppler frequency deviation and the first Doppler frequency deviation; interpolation calculation is performed based on the first Doppler frequency deviation, the second Doppler frequency deviation and the third Doppler frequency deviation to determine the Doppler frequency deviation at the target moment.

[0134] In some embodiments, if the number of second Doppler frequency deviations is one, the second Doppler frequency deviation is a target second Doppler frequency deviation, and if the time interval between the target second moment information and the first moment information of the target second Doppler frequency deviation is greater than a preset interpolation time interval, at least one third Doppler frequency deviation is interpolated between the target second Doppler frequency deviation and the first Doppler frequency deviation.

[0135] In some embodiments, the number of first Doppler frequency deviations is at least two, and the second Doppler frequency deviation closest to the first Doppler frequency deviation on the time axis is used as the target second Doppler frequency deviation. If the time interval between the target second moment information and the first moment information of the target second Doppler frequency deviation is greater than the preset interpolation time interval, at least one third Doppler frequency deviation is interpolated between the target second Doppler frequency deviation and the first Doppler frequency deviation. At the same time, it can be determined on the time axis whether there are two adjacent second Doppler frequency deviations whose time interval is greater than the preset difference time interval.

[0136] If the time interval between two adjacent second Doppler frequency offsets is greater than the preset difference time interval, the two adjacent second Doppler frequency offsets are used as target two adjacent second Doppler frequency offsets, and at least one third Doppler frequency offset is interpolated between the target two adjacent second Doppler frequency offsets.

[0137] In some embodiments, on the time axis, a time interval between two adjacent Doppler frequency offsets among the first Doppler frequency offset, the second Doppler frequency offset, and the third Doppler frequency offset is less than a preset interpolation time interval.

[0138] In this embodiment, by interpolating the third Doppler frequency offset between the first Doppler frequency offset and the second Doppler frequency offset, the number of Doppler frequency offsets used to predict the first target Doppler frequency offset is increased, thereby improving the accuracy of subsequent interpolation calculations to predict the first target Doppler frequency offset.

[0139] In an embodiment of the present application, it is proposed to interpolate a first Doppler frequency deviation calculated by first ephemeris information and a second Doppler frequency deviation calculated by second ephemeris information to predict the target Doppler frequency deviation. Only the Doppler frequency deviation data is interpolated, which can reduce the complexity of the interpolation calculation, reduce the amount of calculation, and efficiently obtain the target Doppler frequency deviation.

[0140] Figure 8 is a flow chart of another Doppler frequency deviation calculation method provided by an embodiment of the present disclosure, the method is executed by a terminal, Figure 8 A method for calculating a target Doppler frequency deviation when the second ephemeris information does not exist is proposed. The method for calculating the Doppler frequency deviation includes:

[0141] S801: Determine a target time difference between a target time and a time corresponding to first time information.

[0142] The first ephemeris information includes first position information and first speed information of the network device at a time corresponding to the first moment information.

[0143] In this embodiment, the target time difference is the delay during an initial access, which may include the transmission delay of sending an uplink synchronization signal and the delay of the initial beam search. The target time difference is the operation time of the network device from the first ephemeris information to the ephemeris information of the target time.

[0144] S802: Determine second position information corresponding to the target time according to the first position information, the first speed information, and the target time difference, wherein the second position information and the target time difference are in a linear relationship.

[0145] In this embodiment, if the second ephemeris information does not exist, the second position information at the target time can be directly determined through a preset relationship.

[0146] In some embodiments, in a preset relationship, there is a linear relationship between the second position information and the target time difference, and the second position information may be the first position information plus the product of the target time difference and the first speed information.

[0147] In some embodiments, the position information may include position data of each coordinate in a three-dimensional coordinate system, then the first position information includes first position data of each coordinate in the three-dimensional coordinate system, the second position information includes second position data of each coordinate in the three-dimensional coordinate system, and the first speed information includes speed data of each coordinate in the three-dimensional coordinate system.

[0148] The product of the target time difference and the first speed information is the product of the speed data at each coordinate and the target time difference, and the running position data at each coordinate can be obtained. The running position data at each coordinate is added to the first position data at the corresponding coordinate to obtain the second position data at each coordinate.

[0149] S803: Use the second position information, the time information corresponding to the target time, and the first speed information as second target ephemeris information, and determine the target Doppler frequency deviation based on the second target ephemeris information.

[0150] In this way, the second position information, the time information corresponding to the target time, and the first speed information can be used as the second target ephemeris information, and the second target ephemeris information can be used as the ephemeris information of the target time, so as to calculate the target Doppler frequency deviation.

[0151] It can be understood that if the initial access of the downlink synchronization information corresponding to the second target ephemeris information fails, the first ephemeris information can be used as the second ephemeris information for the initial access of the next downlink synchronization information.

[0152] In an embodiment of the present application, a method for calculating a target Doppler frequency deviation is disclosed. When the second ephemeris information does not exist, the second target ephemeris information of the network device at the target time can be predicted by the transmission delay, the beam search delay and the first ephemeris information. The target Doppler frequency deviation can be calculated through the second target ephemeris information, thereby improving the accuracy of the target Doppler frequency deviation.

[0153] In some embodiments, the effect of the above-mentioned Doppler frequency deviation calculation method is tested by using relevant simulation software, the time information corresponding to the ephemeris information is set as a known quantity, and different preset difference time intervals are set.

[0154] In one embodiment, the time information used in the simulation is [2, 5, 8, 11, 14] (unit: s), and the corresponding Doppler frequency deviation is [376.87, 374.99, 373.08, 371.16, 369.22] (unit: kHz, kilohertz). In the above data, 14s is the time corresponding to the first time information, 2s, 5s, 8s, and 11s are the times corresponding to different second time information, 369.22kHz is the first Doppler frequency deviation, and 376.87kHz, 374.99kHz, 373.08kHz, and 371.16kHz are the second Doppler frequency deviations corresponding to 2s, 5s, 8s, and 11s, respectively.

[0155] The target time is 17s. The actual Doppler frequency deviation at the target time is compared with the target Doppler frequency deviation obtained by performing the Doppler frequency deviation calculation method disclosed in the present invention on the above data, and the following is obtained: Fig. 9The difference between the actual Doppler frequency deviation and the target Doppler frequency deviation is shown in the figure. Fig. 9 In the figure, the horizontal axis is the known points, corresponding to 2s, 5s, 8s, 11s, 14s, and 17s respectively, and the vertical axis is the Doppler frequency deviation value. The actual Doppler frequency deviation is calculated based on the actual ephemeris information of the network device at the target time. Fig. 9 In the figure, the actual Doppler frequency deviation is 367.25kHz.

[0156] according to Fig. 9 It can be seen that at the known point 6, i.e. 17s, the difference between the actual Doppler frequency offset and the target Doppler frequency offset is less than 4×10 -13 kHz, the error is very small. Assuming that the first Doppler frequency deviation 369.22kHz corresponding to 14s is directly used as the Doppler frequency deviation at the target moment, the corresponding difference is 367.25-369.22=-1.97kHz. Compared with the target Doppler frequency deviation obtained by the Doppler frequency deviation calculation method proposed in the present application, the error is larger. It can be seen that the Doppler frequency deviation calculation method disclosed in the present application can improve the accuracy of the Doppler frequency deviation.

[0157] For another example, taking 10s as the preset interpolation time interval, the data of the known time information is [33, 43, 53, 63, 73], 73s is the time data corresponding to the first time information, and the other data are the time data corresponding to different second time information. The Doppler frequency deviations corresponding to the data of the known time information are [376.87, 370.51, 363.93, 357.13, 350.09], 350.09 is the first Doppler frequency deviation corresponding to the first time information, and the others are the second Doppler frequency deviations at the corresponding moments. The target time is 83s, and the actual Doppler frequency deviation at the target time is 342.82 kHz. The results shown in Table 1 can be obtained.

[0158]

[0159] Table 1

[0160] It can be seen that the target Doppler frequency deviation obtained by the Doppler frequency deviation calculation method disclosed in the present invention has a small error and a high accuracy.

[0161] In other embodiments, based on the target Doppler frequency shift obtained by the above Doppler frequency shift calculation method, an initial access method is also proposed, which is applied to a terminal. The method includes:

[0162] A1. Obtain the target Doppler frequency deviation at the target time determined by the above Doppler frequency deviation calculation method.

[0163] In one embodiment, the terminal receives the downlink synchronization signal sent by the network device at the time corresponding to the first time information, and parses the downlink synchronization signal. The parsing process can refer to Figure 1The method is similar to step S2 in the embodiment of the present invention, but the difference is that the terminal determines the target Doppler frequency deviation at the target time by the Doppler frequency deviation calculation method.

[0164] In some other embodiments, before step A1, the terminal further performs the following steps: Figure 1 The steps corresponding to step S1 in the above are not repeated here.

[0165] A2. Perform frequency deviation compensation processing on the uplink signal based on the target Doppler frequency deviation, and send the uplink signal with the frequency deviation processing to the network device at the target time.

[0166] After the terminal resolves successfully, the terminal will send an uplink signal, namely a random access request. At this time, the uplink signal is frequency-biased compensated by the target Doppler frequency deviation obtained by A1, and the uplink signal with frequency deviation is sent to the network device.

[0167] The network device receives the uplink signal that has undergone frequency deviation processing and analyzes the uplink signal that has undergone frequency deviation processing. If the analysis is successful, the initial access is successful, and the network device feeds back a signal indicating that the initial access is successful to the terminal; if the analysis fails, the initial access fails, and the network device feeds back a signal indicating that the initial access fails to the terminal.

[0168] An initial access method is proposed in an embodiment of the present application, and the difference of the initial access method is that the target Doppler frequency deviation at the target moment is calculated by the Doppler frequency deviation calculation method in the above embodiment, and the uplink signal is subjected to frequency deviation compensation processing by the target Doppler frequency deviation. The initial access method proposed in the embodiment of the present application calculates the target Doppler frequency deviation at the target moment by the Doppler frequency deviation calculation method in the above embodiment to perform frequency deviation compensation processing on the uplink signal, and the accuracy of the target Doppler frequency deviation is high, thereby improving the accuracy of the Doppler frequency deviation compensation, and the frequency deviation of the uplink signal subjected to frequency deviation compensation processing by the target Doppler frequency deviation is small, which can improve the probability of successful resolution of the network device and the probability of successful initial access.

[0169] Fig.10 : is a structural diagram of a Doppler frequency deviation calculation device shown in an exemplary embodiment. The Doppler frequency deviation calculation device is applied to a terminal, and the device includes:

[0170] A receiving module 1010 is configured to receive downlink synchronization information, where the downlink synchronization information indicates first ephemeris information, and the first ephemeris information includes first time information;

[0171] The processing module 1020 is used to calculate the second ephemeris information and the first ephemeris information if there is any, so as to determine the target Doppler frequency deviation corresponding to the target time. The second ephemeris information is information obtained before the time corresponding to the first time information, and the target time indicates the time when the uplink signal is sent to the network device.

[0172] In one implementation, the processing module 1020 further includes:

[0173] A first interpolation unit is used to perform interpolation calculation on the second ephemeris information and the first ephemeris information to determine the first target ephemeris information at the target time;

[0174] The first target Doppler frequency deviation acquiring unit is used to determine the target Doppler frequency deviation based on the first target ephemeris information.

[0175] In an implementable manner, the number of the second ephemeris information is at least one, and different second ephemeris information corresponds to different second time information; and the first interpolation unit includes:

[0176] A first interpolation block is used to interpolate at least one third ephemeris information between two adjacent second ephemeris information of the target on the time axis if the time interval between the second moment information of two adjacent second ephemeris information of the target is greater than a preset interpolation time interval, and / or, if the time interval between the target second moment information and the first moment information of the target second ephemeris information adjacent to the first ephemeris information is greater than the preset interpolation time interval, then interpolate at least one third ephemeris information between the target second ephemeris information and the first ephemeris information;

[0177] The first target ephemeris information acquisition module is used to perform interpolation calculation based on the first ephemeris information, the second ephemeris information and the third ephemeris information to determine the first target ephemeris information at the target time.

[0178] In one implementable manner, interpolation calculation is performed based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time, and the processing module 1020 includes:

[0179] A first frequency deviation obtaining unit, used to determine a first Doppler frequency deviation corresponding to the first ephemeris information;

[0180] A second frequency deviation obtaining unit, used to determine a second Doppler frequency deviation corresponding to the second ephemeris information;

[0181] The second interpolation unit is used to perform interpolation calculation on the first Doppler frequency offset and the second Doppler frequency offset to obtain a target Doppler frequency offset.

[0182] In an implementable manner, the number of the second Doppler frequency offset is at least one, and different Doppler frequency offsets correspond to different second time information; and the second interpolation unit includes:

[0183] A first interpolation block is used to interpolate at least one third ephemeris information between two adjacent second Doppler frequency deviations of the target on the time axis if the time interval between the second moment information of two adjacent second Doppler frequency deviations of the target is greater than a preset interpolation time interval, and / or, if the time interval between the target second moment information and the first moment information of the target second Doppler frequency deviation adjacent to the first Doppler frequency deviation is greater than the preset interpolation time interval, then interpolate at least one third Doppler frequency deviation between the target second Doppler frequency deviation and the first Doppler frequency deviation;

[0184] The target Doppler frequency deviation acquisition section is used to perform interpolation calculation based on the first Doppler frequency deviation, the second Doppler frequency deviation and the third Doppler frequency deviation to determine the target Doppler frequency deviation at the target moment.

[0185] In an implementable manner, the first ephemeris information includes first position information and first speed information of the network device at a time corresponding to the first moment information; if the second ephemeris information does not exist, the Doppler frequency deviation calculation device further includes:

[0186] A target time difference determination module, used to determine a target time difference between a target time and a time corresponding to the first time information;

[0187] A second position information determination module, used to determine second position information corresponding to the target time according to the first position information, the first speed information and the target time difference, wherein the second position information and the target time difference are in a linear relationship;

[0188] The target Doppler frequency deviation determination module is used to use the second position information, the time information corresponding to the target time, and the first speed information as the second target ephemeris information, and determine the target Doppler frequency deviation based on the second target ephemeris information.

[0189] In one possible implementation, the Doppler frequency shift calculation device further includes:

[0190] An initial ephemeris information acquisition module is used to determine initial ephemeris information located before the time corresponding to the first moment information, and the initial ephemeris information corresponds to including initial moment information;

[0191] The second ephemeris information acquisition module is used to use the initial ephemeris information in which the difference between the time corresponding to the initial moment information and the time corresponding to the first moment information is within a preset value range as the second ephemeris information.

[0192] The Doppler frequency offset calculation device provided in this embodiment can be used to execute the above-mentioned Doppler frequency offset calculation method. Its implementation principle and technical effects are similar, and this embodiment will not be repeated here.

[0193] In some embodiments, an initial access device may be provided, which is applied to a terminal, and the initial access device includes: a frequency deviation acquisition module, which is used to obtain the target Doppler frequency deviation at the target time determined by the above-mentioned Doppler frequency deviation calculation method; an uplink signal sending module, which is used to perform frequency deviation compensation processing on the uplink signal based on the target Doppler frequency deviation, and send the uplink signal with frequency deviation processing to the network device at the target time.

[0194] The initial access device provided in the embodiment can be used to execute the above-mentioned initial access method. Its implementation principle and technical effects are similar, and this embodiment will not be repeated here.

[0195] Fig.11 This is a schematic diagram of the structure of a terminal shown in an exemplary embodiment. Fig.11 The terminal 1100 may include: a processor 1101 and a memory 1102, wherein the processor 1101 and the memory 1102 can communicate; illustratively, the processor 1101 and the memory 1102 communicate via a communication bus 1103, the memory 1102 is used to store computer execution instructions, and the processor 1101 is used to call the computer execution instructions in the memory to execute the Doppler frequency deviation calculation method shown in any of the above method embodiments.

[0196] In some embodiments, the terminal further includes a transceiver for receiving downlink synchronization information or sending uplink signals.

[0197] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the present application may be directly implemented as being executed by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor.

[0198] The present application provides a computer-readable storage medium, on which computer-executable instructions are stored; when the computer-executable instructions are executed by a processor, they are used to implement a Doppler frequency deviation calculation method as described in any of the above embodiments.

[0199] An embodiment of the present application provides a computer program product, which includes a computer program. When the computer program is executed, the computer executes the above-mentioned Doppler frequency deviation calculation method.

[0200] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0201] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A Doppler frequency deviation calculation method, characterized in that: Applied to a terminal, the method comprises: receiving downlink synchronization information, where the downlink synchronization information indicates first ephemeris information, and the first ephemeris information includes first time information; If there is second ephemeris information, a calculation is performed based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time, wherein the second ephemeris information is information obtained before the time corresponding to the first time information, and the target time indicates the time when an uplink signal is sent to the network device.

2. The method according to claim 1, characterized in that The calculating based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time includes: Performing interpolation calculation on the second ephemeris information and the first ephemeris information to determine first target ephemeris information at the target time; The target Doppler frequency offset is determined based on the first target ephemeris information.

3. The method according to claim 2, characterized in that The number of the second ephemeris information is at least one, and different second ephemeris information corresponds to different second time information; and the interpolation calculation of the second ephemeris information and the first ephemeris information to determine the first target ephemeris information at the target time includes: On the time axis, if the time interval between the second moment information of two adjacent second ephemeris information of the target is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the two adjacent second ephemeris information of the target, and / or, if the time interval between the target second moment information of the target second ephemeris information adjacent to the first ephemeris information and the first moment information is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the target second ephemeris information and the first ephemeris information; An interpolation calculation is performed based on the first ephemeris information, the second ephemeris information and the third ephemeris information to determine first target ephemeris information at the target time.

4. The method according to claim 1, characterized in that: The calculating based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time includes: Determining a first Doppler frequency offset corresponding to the first ephemeris information; Determining a second Doppler frequency offset corresponding to the second ephemeris information; An interpolation calculation is performed on the first Doppler frequency offset and the second Doppler frequency offset to obtain the target Doppler frequency offset.

5. The method according to claim 4, characterized in that The number of the second Doppler frequency offsets is at least one, and different Doppler frequency offsets correspond to different second time information; and the interpolation calculation of the first Doppler frequency offset and the second Doppler frequency offset to obtain the target Doppler frequency offset includes: On the time axis, if the time interval between the second moment information of two adjacent second Doppler frequency deviations of the target is greater than the preset interpolation time interval, at least one third ephemeris information is interpolated between the two adjacent second Doppler frequency deviations of the target, and / or, if the time interval between the target second moment information of the target second Doppler frequency deviation adjacent to the first Doppler frequency deviation and the first moment information is greater than the preset interpolation time interval, at least one third Doppler frequency deviation is interpolated between the target second Doppler frequency deviation and the first Doppler frequency deviation; An interpolation calculation is performed based on the first Doppler frequency offset, the second Doppler frequency offset, and the third Doppler frequency offset to determine the Doppler frequency offset at the target time.

6. The method according to any one of claims 1 to 5, characterized in that: The first ephemeris information includes first position information and first speed information of the network device at a time corresponding to the first moment information; If the second ephemeris information does not exist, the method further includes: Determine a target time difference between the target time and a time corresponding to the first time information; Determine second position information corresponding to the target time according to the first position information, the first speed information and the target time difference, wherein there is a linear relationship between the second position information and the target time difference; The second position information, the time information corresponding to the target time, and the first speed information are used as second target ephemeris information, and the target Doppler frequency deviation is determined based on the second target ephemeris information.

7. The method according to any one of claims 1 to 5, characterized in that: Before performing calculation based on the second ephemeris information and the first ephemeris information to determine the target Doppler frequency deviation corresponding to the target time, the method further includes: Determine initial ephemeris information before the time corresponding to the first moment information, wherein the initial ephemeris information includes initial moment information; The initial ephemeris information in which the difference between the time corresponding to the initial time information in the initial ephemeris information and the time corresponding to the first time information is within a preset value range is used as the second ephemeris information.

8. An initial access method, characterized in that: Applied to a terminal, the method comprises: Obtaining a target Doppler frequency deviation at a target time determined by the method according to any one of claims 1 to 7; The uplink signal is subjected to frequency deviation compensation processing based on the target Doppler frequency deviation, and the uplink signal subjected to the frequency deviation processing is sent to the network device at the target time.

9. A Doppler frequency deviation calculation device, characterized in that: Applied to a terminal, the device comprises: A receiving module, configured to receive downlink synchronization information, wherein the downlink synchronization information indicates first ephemeris information, and the first ephemeris information includes first time information; A processing module is used to calculate the second ephemeris information and the first ephemeris information if there is any, so as to determine the target Doppler frequency deviation corresponding to the target time, wherein the second ephemeris information is information obtained before the time corresponding to the first time information, and the target time indicates the time when the uplink signal is sent to the network device.

10. A terminal, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 1 to 8.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 8 when executed by a processor.

12. A computer program product, characterized in that The invention comprises a computer program, which implements the method according to any one of claims 1 to 8 when being executed by a processor.

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