A method for determining residual time offset, a method for determining time-domain transmission signal, a program product, an electronic device and a storage medium

Abstract

The application provides a residual time offset determination method, a time domain transmitting signal determination method, a program product, an electronic device and a storage medium, and is applied to the technical field of communication. The residual time offset determination method comprises the following steps: receiving a plurality of initial time domain receiving signals, and determining a corresponding initial frequency domain receiving signal according to each initial time domain receiving signal; determining an integer multiple offset in the residual time offset of the initial time domain receiving signal as a corresponding target offset parameter, wherein the residual time offset represents the deviation between the actual time of receiving the initial time domain receiving signal and the expected time of receiving the initial time domain receiving signal, and the residual time offset comprises an integer multiple offset and a decimal multiple offset; and determining the residual time offset according to the initial frequency domain receiving signal and the target offset parameter. On the premise of guaranteeing the detection and time offset estimation performance, the estimation range of the residual time offset in the prior art is expanded, and thus the error of the residual time offset estimation in the prior art can be effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication, in particular to a residual time offset determination method, a time domain transmitted signal determination method, a program product, an electronic device and a storage medium. BACKGROUND

[0002] In a 5G communication system, a terminal needs to transmit a physical random access channel (PRACH) signal to a base station in an initial access process to realize the function of random access. In the initial access stage, since the uplink (the link of the terminal transmitting a signal to the base station is called uplink) synchronization has not been completed, the base station needs to measure the residual time offset of the PRACH signal and notify the terminal of the corresponding time delay adjustment through signaling to realize the time synchronization of the uplink signal. However, in the prior art, the error of the base station estimating the residual time offset of the uplink is large. SUMMARY

[0003] The purpose of the embodiments of the present application is to provide a residual time offset determination method, a time domain transmitted signal determination method, a program product, an electronic device and a storage medium to solve the technical problem that the error of the base station estimating the residual time offset of the uplink is large in the prior art.

[0004] In a first aspect, the embodiments of the present application provide a residual time offset determination method applied to a base station, comprising: receiving a plurality of initial time domain received signals, and determining a corresponding initial frequency domain received signal according to each initial time domain received signal, wherein the plurality of initial time domain received signals correspond one-to-one to time domain transmitted signals repeatedly transmitted by a terminal; determining a target offset parameter corresponding to an integer multiple offset in a residual time offset of the initial time domain received signal, wherein the residual time offset represents a deviation between an actual time of receiving the initial time domain received signal and an expected time of receiving the initial time domain received signal, and the residual time offset includes the integer multiple offset and a decimal multiple offset; and determining the residual time offset according to the initial frequency domain received signal and the target offset parameter.

[0005] In the above scheme, by separating the integer multiple offset and the decimal multiple offset in the residual time offset, the target offset parameter corresponding to the integer multiple offset is first determined, and then the residual time offset is comprehensively calculated in combination with the initial frequency domain received signal, which not only considers the influence of the integer multiple offset on signal synchronization, but also accurately calculates the decimal multiple offset, so that the estimation range of the residual time offset in the prior art can be expanded under the premise of ensuring the PRACH detection and time offset estimation performance, thereby effectively reducing the error of the residual time offset estimation in the prior art.

[0006] In an optional implementation, the time-domain transmitted signal is obtained by performing an inverse Fourier transform on the target frequency-domain transmitted signal, and the target frequency-domain transmitted signal is obtained by performing a phase rotation process on the initial frequency-domain transmitted signal; determining the target offset parameter corresponding to the integer multiple offset in the residual time offset of the initial time-domain received signal includes: for each candidate offset parameter, determining the initial frequency-domain received signal corresponding to the candidate offset parameter; performing a phase-rotation cancellation process on each initial frequency-domain received signal corresponding to the candidate offset parameter to obtain the target frequency-domain received signal corresponding to each initial frequency-domain received signal; performing residual time delay estimation based on multiple target frequency-domain received signals corresponding to the candidate offset parameter to obtain the time-domain merging correlation waveform corresponding to the candidate offset parameter; and determining the candidate offset parameter with the largest peak value of the time-domain merging correlation waveform among multiple candidate offset parameters as the target offset parameter.

[0007] In the above scheme, during the process of traversing candidate offset parameters, if the candidate offset parameter matches the true value, the phase rotation effect at the terminal is canceled out. In subsequent detection, the time-domain correlation waveforms at different PRACH repetition positions have the same shape, and after superposition, the correlation peaks overlap to obtain a merging gain, ensuring detection performance is the same as existing technologies. If the candidate offset parameter does not match the true value, the peak values ​​of the time-domain correlation waveforms at different PRACH repetition positions will be staggered during subsequent detection, and after superposition, no merging gain can be obtained, resulting in smaller correlation peaks. Therefore, this peak-based screening method can more accurately determine the target offset parameter corresponding to integer multiple offsets, reducing errors caused by improper offset parameter selection. Simultaneously, by canceling phase rotation processing, the signals from each repeated transmission are better aligned in the frequency domain, enhancing signal coherence, improving the reliability of residual time offset estimation, and further optimizing uplink synchronization performance.

[0008] In an optional implementation, determining the initial frequency domain received signal corresponding to the candidate offset parameter includes: if the candidate offset parameter If the value is not less than 0, then the initial frequency domain received signal corresponding to the candidate offset parameter is determined to be the first... The first reception corresponds to the initial frequency domain received signal until the second reception. The initial frequency domain received signal corresponding to the next reception, wherein... To receive the total number of times, If the candidate offset parameter If the value is less than 0, then the initial frequency domain received signal corresponding to the candidate offset parameter is determined to be the initial frequency domain received signal from the first reception to the second reception. The first reception corresponds to the initial frequency domain received signal.

[0009] In the above scheme, by explicitly defining the range of the initial frequency domain received signal corresponding to different candidate offset parameters, it is ensured that all valid signals related to the current candidate parameter can be covered in the processing process, avoiding signal omission or invalid signal interference, so that the evaluation of the candidate offset parameter is more comprehensive and accurate, thereby improving the effectiveness of the entire residual time offset estimation process.

[0010] In an optional implementation, the canceling phase rotation processing on each initial frequency domain received signal corresponding to the candidate offset parameter to obtain a target frequency domain received signal corresponding to each initial frequency domain received signal comprises: for the initial frequency domain received signal corresponding to each repeated transmission, determining the product between the initial frequency domain received signal and the conjugate of the time delay sequence corresponding to the repeated transmission as the target frequency domain received signal corresponding to the repeated transmission, wherein the time delay sequence is used for phase rotation processing on the initial frequency domain transmitted signal to obtain the target frequency domain transmitted signal.

[0011] In the above scheme, the canceling phase rotation processing is realized by multiplying the initial frequency domain received signal and the conjugate of the corresponding time delay sequence, which can effectively eliminate the influence of the preset time delay introduced by the frequency domain phase rotation of the terminal transmitted signal, so that the target frequency domain received signals of each repeated transmission remain better consistency in the frequency domain.

[0012] In an optional implementation, the determining of the residual time offset according to the initial frequency domain received signal and the target offset parameter comprises: residual time offset estimation on the initial frequency domain received signal to obtain the fractional offset, and determining the integer offset according to the subcarrier spacing corresponding to the initial frequency domain received signal and the target offset parameter; and determining the residual time offset according to the fractional offset and the integer offset.

[0013] In the above scheme, the fractional offset and the integer offset are determined respectively, and then the residual time offset is obtained by combining the two, which fully utilizes the characteristics of different offset types for targeted estimation. The estimation of the fractional offset can be realized by a fine signal processing algorithm to achieve high-precision calculation, and the integer offset is determined in combination with the subcarrier spacing and the target offset parameter, and the combination of the two can improve the accuracy of the determination of the residual time offset.

[0014] In an optional implementation, the residual time offset estimation on the initial frequency domain received signal comprises: determining the initial frequency domain received signal corresponding to the target offset parameter; and performing residual time offset estimation on the initial frequency domain received signal corresponding to the target offset parameter.

[0015] In the above scheme, since the target offset parameter is the optimal parameter selected, the estimation based on the corresponding signal can improve the estimation accuracy of the fractional offset, and then the integer offset is combined to obtain a more accurate residual time offset.

[0016] In a second aspect, the embodiments of the present application provide a residual time offset determination method applied to a base station, comprising: receiving a plurality of initial time domain received signals, wherein the plurality of initial time domain received signals correspond to time domain transmitted signals repeatedly transmitted by a terminal; determining a target offset parameter corresponding to an integer multiple offset in a residual time offset of the initial time domain received signal, wherein the residual time offset represents a deviation between an actual time of receiving the initial time domain received signal and an expected time of receiving the initial time domain received signal, and the residual time offset comprises the integer multiple offset and a decimal multiple offset; and determining the residual time offset according to the initial time domain received signal and the target offset parameter.

[0017] In the above scheme, by separating the integer multiple offset and the decimal multiple offset in the residual time offset, the target offset parameter corresponding to the integer multiple offset is determined first, and then the residual time offset is calculated in combination with the initial time domain received signal, which not only considers the influence of the integer multiple offset on signal synchronization, but also accurately calculates the decimal multiple offset, so that the estimation range of the residual time offset in the prior art can be expanded while ensuring the performance of PRACH detection and time offset estimation, thereby effectively reducing the error of residual time offset estimation in the prior art.

[0018] In an optional implementation, the time domain transmitted signal is obtained by inverse Fourier transform on a target frequency domain transmitted signal, and the target frequency domain transmitted signal is obtained by phase rotation processing on an initial frequency domain transmitted signal; the determination of the target offset parameter corresponding to the integer multiple offset in the residual time offset of the initial time domain received signal comprises: for each candidate offset parameter, determining the initial time domain received signal corresponding to the candidate offset parameter; performing cancellation phase rotation processing on each initial time domain received signal corresponding to the candidate offset parameter to obtain a target time domain received signal corresponding to each initial time domain received signal; performing residual time delay estimation on a plurality of target time domain received signals corresponding to the candidate offset parameter to obtain a time domain combined correlation waveform corresponding to the candidate offset parameter; and determining the candidate offset parameter with the maximum peak value of the time domain combined correlation waveform in the plurality of candidate offset parameters as the target offset parameter.

[0019] In the above scheme, in the process of traversing the candidate offset parameter, if the candidate offset parameter is consistent with the true value, then the phase rotation effect of the terminal is cancelled, the time domain correlation waveform shapes of different PRACH repetition positions are the same in the subsequent detection process, the correlation peaks are superimposed together to obtain the merging gain, and the detection performance is the same as the prior art; if the candidate offset parameter is inconsistent with the true value, then the peak values of the time domain correlation waveforms of different PRACH repetition positions are staggered with each other in the subsequent detection process, and the correlation peaks cannot obtain the merging gain after being superimposed. Therefore, this peak value screening based method can more accurately determine the target offset parameter corresponding to the integer multiple offset, and reduce the error caused by improper selection of the offset parameter. At the same time, by cancelling the phase rotation processing, the signals of each repetition transmission are better aligned in the frequency domain, the coherence of the signals is enhanced, the reliability of the residual time offset estimation is improved, and the uplink synchronization effect is further optimized.

[0020] In a third aspect, the embodiments of the present application provide a time domain transmission signal determination method applied to a terminal, comprising: obtaining an initial frequency domain transmission signal; for any one repetition transmission, performing phase rotation processing on the initial frequency domain transmission signal corresponding to the repetition transmission to obtain a target frequency domain transmission signal corresponding to the repetition transmission; and generating a time domain transmission signal corresponding to the repetition transmission according to the target frequency domain transmission signal, and transmitting the time domain transmission signal in the repetition transmission.

[0021] In the above scheme, the terminal generates a target frequency domain transmission signal by performing phase rotation processing on an initial frequency domain transmission signal, and then converts the target frequency domain transmission signal into a time domain transmission signal for multiple repetition transmissions, so that the base station can find the optimal target offset parameter by canceling the phase rotation effect after receiving the time domain transmission signal, thereby expanding the estimation range of the residual time offset in the prior art while ensuring the PRACH detection and time offset estimation performance, and effectively reducing the error of the residual time offset estimation in the prior art.

[0022] In an optional implementation, the phase rotation processing on the initial frequency domain transmission signal corresponding to the repetition transmission comprises: generating a time delay sequence corresponding to the repetition transmission according to a time delay parameter corresponding to the repetition transmission and a length of the initial frequency domain transmission signal; and determining the product between the initial frequency domain transmission signal and the time delay sequence as the target frequency domain transmission signal.

[0023] In the above scheme, the phase rotation processing is realized by multiplying the initial frequency domain transmitting signal with the time delay sequence, so that the base station can realize the phase rotation cancellation processing by multiplying the initial frequency domain receiving signal with the conjugate of the corresponding time delay sequence, the preset time delay influence introduced by the frequency domain phase rotation of the terminal transmitting signal can be effectively eliminated, and the target frequency domain receiving signals of each repeated transmission can keep better consistency in the frequency domain.

[0024] In an optional implementation, the time delay sequence corresponding to the repeated transmission is generated according to the time delay parameter corresponding to the repeated transmission and the length of the initial frequency domain transmitting signal, including: determining the time delay sequence by using the following formula:

[0025] ;

[0026] Wherein, is the time delay sequence, is the serial number of the frequency domain subcarrier , is the length of the initial frequency domain transmitting signal, is the time delay parameter, and , is the receiving number, , is the total receiving number, is the configuration parameter, and .

[0027] In the above scheme, the time delay parameter adopts a quadratic function form, which can ensure that the generated time delay sequence has a reasonable time delay length distribution, so that the signals of multiple repeated transmissions form an effective multipath distribution in the time domain, which not only avoids signal overlapping, but also realizes good coherent superposition at the base station end.

[0028] In a fourth aspect, an embodiment of the present application provides a computer program product, including computer program instructions, which are read and run by a processor to execute the residual time delay determination method according to the first aspect and the second aspect or the time domain transmitting signal determination method according to the second aspect.

[0029] In a fifth aspect, an embodiment of the present application provides an electronic device, including a processor, a memory and a bus; the processor and the memory complete mutual communication through the bus; the memory stores computer program instructions executable by the processor, and the processor calling the computer program instructions can execute the residual time delay determination method according to the first aspect and the second aspect or the time domain transmitting signal determination method according to the second aspect.

[0030] In a sixth aspect, an embodiment of the present application provides a computer readable storage medium storing computer program instructions, when the computer program instructions are run by a computer, the computer is caused to perform the residual time offset determination method according to the first aspect or the second aspect or the time domain transmission signal determination method according to the second aspect.

[0031] In order to make the above objectives, characteristics and advantages of the present application more apparent, clear and easy to understand, the following will describe embodiments of the present application in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be considered as a limitation to the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0033] Figure 1 A flow chart of the residual time offset determination method according to an embodiment of the present application is provided.

[0034] Figure 2 A flow chart of the time domain transmission signal determination method according to an embodiment of the present application is provided.

[0035] Figure 3 A structural block diagram of the electronic device according to an embodiment of the present application is provided. DETAILED DESCRIPTION

[0036] In the description of the present application, unless otherwise specified, " / " means "or", for example, A / B can mean A or B. "And / or" in this document only describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can mean that A exists alone, A and B exist together, and B exists alone. In addition, "at least one" means one or more, and "multiple" means two or more. "First", "second", etc. do not limit the quantity and execution order, and "first", "second", etc. do not necessarily mean different.

[0037] It should be noted that in the present application, "exemplary" or "for example" means to serve as an example, illustration or description. Any embodiment or design scheme described as "exemplary" or "for example" in the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the use of "exemplary" or "for example" is intended to specifically present the relevant concept in a specific manner.

[0038] Before the technical solutions of the embodiments of the present application are described, the communication system of the embodiments of the present application is first described. The communication system provided by the embodiments of the present application includes an access device and a terminal. In the process of implementing the embodiments of the present application, the terminal can be a computer, a smart phone, a telephone, a cable television set-top box, a digital subscriber line router and the like. The access device can be one of a ground base station, an aerial base station, a low earth orbit satellite, a medium earth orbit satellite and a high earth orbit satellite. It should be noted that in actual application, the number of the access device and the terminal can be one or more, which is not limited by the present application.

[0039] The above communication system can be applied to a Long Term Evolution (LTE) system or an NR system (also referred to as a 5th Generation (5G) system), a system of mixed networking of LTE and NR, a Vehicle to Everything (V2X) system, a Device-to-Device (D2D) system, a Machine to Machine (M2M) communication system, an Internet of Thing (IoT) system (such as a Narrow Band Internet of Thing (NB-IoT) system), a 6G system and the like, a system evolved after 5G, and other next-generation communication systems. Alternatively, the communication system can also be an Open Radio Access Network (O-RAN or ORAN), a Loud RAN (CRAN), or a Wireless Fidelity (Wi-Fi) system, without limitation.

[0040] The access device can be used to support terminal access, for example, can be a Base Transceiver Station (BTS) and a Base Station Controller (BSC) in a 2G access technology communication system, a Node B and a Radio Network Controller (RNC) in a 3G access technology communication system, an Evolved Node B (eNB) in a 4G access technology communication system, a Next Generation Node B (gNB) in a 5G access technology communication system, a Transmission Reception Point (TRP), a Relay Node, an Access Point (AP) and the like ground equipment, and can also be a non-ground equipment: a high-altitude base station, for example: a device such as a hot air balloon that can provide wireless access function for a terminal, a low-orbit satellite, a medium-orbit satellite, a high-orbit satellite and the like. For convenience of description, all the devices providing wireless communication function for the terminal in the embodiments of the present application are collectively referred to as base stations.

[0041] The terminal can be a device providing voice or data connectivity for a user, for example, also known as a mobile station, a subscriber unit, a station, a terminal equipment (TE), etc. The terminal can be a cellular phone, a personal digital assistant (PDA), a wireless modem, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a pad, etc. With the development of wireless communication technology, devices that can access a communication system, communicate with the network side of the communication system, or communicate with other objects through the communication system can all be terminals in the embodiments of the present application, for example, terminals and cars in intelligent transportation, home devices in smart home, power metering instruments, voltage monitoring instruments, environmental monitoring instruments in smart power grid, video monitoring instruments in intelligent security network, cash registers, etc. In the embodiments of the present application, the terminal can communicate with the base station. Multiple terminals can also communicate with each other. The terminal can be static and fixed, or mobile.

[0042] In addition, the "protocol" involved in the embodiments of the present application can refer to a standard protocol in the communication field, which can include an LTE protocol, a New Radio (NR) protocol, and a related protocol applied in a future communication system (for example, a 6G communication system), and the embodiments of the present application do not limit this. The communication architecture and the service scenario described in the embodiments of the present application are for more clearly illustrating the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. It can be known by those skilled in the art that, with the evolution of the communication architecture and the appearance of new service scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

[0043] In the above communication system, the terminal needs to transmit a PRACH signal to the base station in the initial access process to realize the function of random access. The following briefly introduces the random access process in the prior art.

[0044] In the first step, the terminal determines the predetermined subcarrier frequency (corresponding to the subcarrier interval, such as 1.25 kHz, 15 kHz, etc.) of the PRACH according to the system information broadcast by the base station. Based on the subcarrier interval, the terminal generates a frequency domain signal of the PRACH preamble sequence and maps it to the continuous subcarriers to form an initial frequency domain transmission signal. The subcarrier interval determines the symbol period of the PRACH signal, and further limits the estimation range of the residual time offset.

[0045] In the second step, the terminal transmits the same PRACH signal for a plurality of times according to the repetition number configured by the network (such as 2, 4, 8, etc.). The repeated transmission is to improve the detection performance of the PRACH and the estimation accuracy of the residual time offset.

[0046] In the third step, after the base station obtains the PRACH signal through the receiving antenna, the base station first converts each PRACH signal into a correlation power waveform, then superimposes a plurality of correlation power waveforms to complete the PRACH signal detection and the residual time offset estimation.

[0047] In the fourth step, the base station feeds back the PRACH detection result (including whether it is detected, the preamble index, etc.) and the residual time offset estimation value to the terminal through the downlink channel (such as PDSCH, etc.). The terminal adjusts the transmission time according to the feedback time offset compensation amount to complete the uplink time synchronization, and then enters the subsequent process of random access (such as sending an RRC connection request, etc.).

[0048] In the above random access process, the estimation range of the residual time offset is determined by the subcarrier interval of the PRACH signal. In the scenario where the range of the time offset changes greatly (for example, a satellite communication scenario), the uplink residual time offset may be greater than the range supported by the prior art. At this time, the uplink residual time offset estimation of the base station will have a large error, which leads to the fact that the terminal cannot complete the random access.​

[0049] In view of this, the embodiments of the present application provide a residual time offset determination method and a time domain transmitted signal determination method, which can greatly increase the estimation range of residual time offset without changing the existing PRACH signal subcarrier spacing and time-frequency resource, and solve the problem of excessive time offset estimation error of the prior art when the uplink residual time delay changes greatly.

[0050] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

[0051] Referring to Figure 1 , Figure 1 A flowchart of a residual time offset determination method provided by the embodiments of the present application is provided, which can be executed by a base station, or by a component of the base station, such as a processor, a chip, a chip system or a circuit of the base station, or by a logic module or software capable of realizing all or part of the functions of the base station. The following takes the method executed by the base station as an example for description, and the method can specifically include the following steps:

[0052] S101: receiving a plurality of initial time domain received signals, and determining a corresponding initial frequency domain received signal according to each initial time domain received signal.

[0053] S102: determining a target offset parameter corresponding to an integer multiple offset in the residual time offset of the initial time domain received signal.

[0054] S103: determining the residual time offset according to the initial frequency domain received signal and the target offset parameter.

[0055] Specifically, in the above S101, the plurality of initial time domain received signals correspond one-to-one to the time domain transmitted signals repeatedly transmitted by the terminal multiple times. As described above, the terminal can transmit the same time domain transmitted signal according to the repetition number configured by the network, wherein the time domain transmitted signal is a time domain signal formed by mapping the frequency domain signal generated by the terminal based on the subcarrier spacing to the continuous subcarriers. It should be noted that the embodiments of the present application do not make specific limitations on the specific value of the above-mentioned repetition number and the specific generation method of the time domain transmitted signal, and the person skilled in the art can make appropriate adjustments according to the actual situation.

[0056] The signal transmitted by the terminal is affected by factors such as propagation attenuation, noise interference, time offset error, and the like, so that the signal received by the base station is usually inconsistent with the signal transmitted by the terminal. Therefore, the initial time domain received signal in S101 refers to the time domain signal received by the base station, which corresponds to the time domain signal (i.e. the frequency domain transmitted signal) transmitted by the terminal. In the embodiments of the present application, since the number of time domain transmitted signals sent by the terminal is multiple, the number of initial time domain received signals received by the base station is also multiple, and each initial time domain received signal corresponds to the time domain transmitted signal sent by the terminal once.

[0057] The base station receives the time domain transmitted signal according to the preset PRACH receiving time-frequency position. The base station defines the specific position of the PRACH signal in the time domain (time domain) and the frequency domain (frequency domain) in advance to form a PRACH resource pool, which is used to listen to and receive the PRACH signal sent by the terminal.

[0058] It can be understood that due to the residual time offset, the time domain transmitted signal received by the base station according to the above-mentioned PRACH receiving time-frequency position may not be complete, that is, the initial time domain received signal only includes a part of the time domain transmitted signal. The residual time offset represents the deviation between the time when the base station actually receives the initial time domain received signal and the time when the base station expects to receive the initial time domain received signal.

[0059] That is, if there is a large deviation between the PRACH receiving time preset by the base station and the PRACH actual arrival time, for example, the deviation exceeds the time length of a single PRACH signal (the time length is equal to the reciprocal of the PRACH subcarrier interval), which will cause the base station to count the PRACH repeated position incorrectly. For example, assuming that the frequency domain signal corresponding to the time domain transmitted signal sent by the terminal is , the initial frequency domain received signal corresponding to the initial time domain received signal received by the base station is , then , wherein is the number of times of receiving, , is the total number of times of receiving, is the serial number of the frequency domain subcarrier, which is used to identify the specific position of the PRACH signal in the frequency domain, , is the length of the initial frequency domain transmitted signal.

[0060] For each initial time domain received signal received, the base station can convert the initial time domain received signal to the frequency domain, and obtain the corresponding initial frequency domain received signal through resource demapping. For example, for the time domain transmitted signal sent by the terminal for the first time, the base station receives the initial time domain received signal for the first time at the first time, and converts the initial time domain received signal for the first time to the frequency domain to obtain the initial frequency domain received signal for the first time. For the time domain transmitted signal sent by the terminal for the second time, the base station receives the initial time domain received signal for the second time at the second time, and converts the initial time domain received signal for the second time to the frequency domain to obtain the initial frequency domain received signal for the second time. The base station receives an initial time domain receiving signal corresponding to the time domain transmitting signal, and obtains an initial frequency domain receiving signal corresponding to the initial time domain receiving signal according to the initial time domain receiving signal.

[0061] It can be understood that since the base station determines the key parameters (for example, the repetition number, the repetition time interval, the time domain length of a single signal, etc.) of the time domain transmitting signal repeatedly transmitted by the terminal in advance through network configuration, the base station can determine a total receiving window based on the key parameters. In the total receiving window, the base station receives signals according to the receiving time-frequency positions, and performs signal detection on the received signals: by performing correlation operation with a local reference sequence, it is judged whether there is an effective signal at the position. When the number of effective signals detected by the base station in the total receiving window is equal to the preset repetition number, it can be considered that the time domain transmitting signal repeatedly transmitted by the terminal multiple times is received, and subsequent steps are performed.

[0062] In S102 described above, as described above, the residual time offset refers to the deviation between the time at which the base station actually receives the initial time domain receiving signal and the time at which the base station is expected to receive the initial time domain receiving signal, which can include an integer multiple offset and a decimal multiple offset. Therefore, when determining the residual time offset of the base station, the decimal multiple offset, the integer multiple offset and the multiple of the integer multiple offset in the residual time offset need to be determined.

[0063] The decimal multiple offset can be obtained by performing residual time offset estimation on the initial frequency domain receiving signal; the integer multiple offset can be determined according to the subcarrier spacing corresponding to the PRACH signal; and the multiple of the integer multiple offset, i.e. the target offset parameter in the embodiment of the application, can be obtained by performing S102.

[0064] It should be noted that the specific implementation of determining the target offset parameter described above is not specifically limited in the embodiment of the application, and those skilled in the art can make appropriate adjustments according to the actual situation. For example, the target offset parameter can be determined according to experience; or the target offset parameter can be determined by experiment in advance; or the target offset parameter can be determined by using a deep learning model; or the target offset parameter can be determined by screening the maximum peak value of the time domain combined correlation waveform, etc.

[0065] In S103 described above, the residual time offset can be determined according to the initial frequency domain receiving signal and the target offset parameter. For example, the residual time offset can be determined by the following formula:

[0066] ;

[0067] Wherein, is the residual time offset, is the decimal multiple offset, , is the integer multiple offset, , The subcarrier spacing corresponding to the PRACH signal. This refers to the target offset parameter.

[0068] In the above scheme, by separating the integer multiple offset and the fractional multiple offset in the residual time offset, the target offset parameter corresponding to the integer multiple offset is first determined, and then the residual time offset is calculated by combining the initial frequency domain received signal. This takes into account both the impact of the integer multiple offset on signal synchronization and accurately calculates the fractional multiple offset. Thus, while ensuring the performance of PRACH detection and time offset estimation, the estimation range of the residual time offset in the prior art can be expanded, thereby effectively reducing the error of residual time offset estimation in the prior art.

[0069] The following describes a specific implementation method for determining target offset parameters provided by an embodiment of this application. In this implementation method, before transmitting a time-domain transmission signal, the terminal can first perform phase rotation processing on the initial frequency-domain transmission signal to obtain a target frequency-domain transmission signal, and then perform inverse Fourier transform on the target frequency-domain transmission signal to obtain a time-domain transmission signal. Correspondingly, the base station can perform phase rotation cancellation processing on the initial frequency-domain received signal to select the target candidate offset parameter that maximizes the peak value of the time-domain merged related waveform from multiple candidate offset parameters, thereby determining the residual time offset.

[0070] It is understandable that performing phase rotation on a frequency domain signal is equivalent to performing cyclic shift on a time domain signal; correspondingly, performing phase rotation cancellation on a frequency domain signal is equivalent to performing cyclic shift cancellation on a time domain signal. As one implementation method, phase rotation on the frequency domain signal can be achieved by multiplying it by a time delay sequence; alternatively, phase rotation cancellation can be achieved by multiplying the frequency domain signal by the conjugate of the time delay sequence.

[0071] At this point, S102 may specifically include the following steps:

[0072] S201: For each candidate offset parameter, determine the initial frequency domain received signal corresponding to that candidate offset parameter.

[0073] S202: Perform phase rotation cancellation processing on each initial frequency domain received signal corresponding to the candidate offset parameter to obtain the target frequency domain received signal corresponding to each initial frequency domain received signal.

[0074] S203: Based on the multiple target frequency domain received signals corresponding to the candidate offset parameter, perform residual time delay estimation to obtain the time domain merging correlation waveform corresponding to the candidate offset parameter.

[0075] S204: Determine the candidate offset parameter with the largest peak value of the time-domain merged correlation waveform among multiple candidate offset parameters as the target offset parameter.

[0076] Specifically, in determining the residual time offset, since the base station does not know the magnitude of the integer multiple offset, it is necessary to select a candidate offset parameter from multiple candidate offset parameters as the target offset parameter. It should be noted that this application does not impose specific limitations on the specific values ​​of the candidate offset parameter; those skilled in the art can make appropriate adjustments based on actual circumstances. As one implementation method, ,in, Candidate offset parameters, The total number of times to send (i.e., the total number of times to receive), for example: when When the offset parameter can be -2, -1, 0, 1, or 2, the candidate offset parameter can be -2, -1, 0, 1, or 2.

[0077] It is understood that the candidate offset parameter should be an integer. A positive integer candidate offset parameter indicates a delay between the actual time the base station receives the initial time-domain received signal and the expected time. A negative integer candidate offset parameter indicates an advance between the actual time the base station receives the initial time-domain received signal and the expected time. A candidate offset parameter of 0 indicates that there is no integer multiple offset between the actual time the base station receives the initial time-domain received signal and the expected time.

[0078] As mentioned earlier, due to residual time offset, the time-domain transmitted signal received by the base station may be incomplete; that is, the initial time-domain received signal only includes a portion of the time-domain transmitted signal. In S201 above, since the residual time offset corresponding to each candidate offset parameter is different, the time-domain transmitted signal received by the base station is different for each candidate offset parameter; correspondingly, the initial frequency-domain received signal corresponding to each candidate offset parameter is also different. It can be understood that one candidate offset parameter can correspond to multiple initial frequency-domain received signals.

[0079] For example, suppose the initial frequency domain transmitted signal includes signal 1, signal 2, signal 3, signal 4, and signal 5, and the target frequency domain transmitted signal obtained after phase rotation processing includes signal 3, signal 4, signal 5, signal 1, and signal 2. Then: if the candidate offset parameter is -2, the initial frequency domain received signal received by the base station includes signal 5, signal 1, and signal 2; if the candidate offset parameter is -1, the initial frequency domain received signal received by the base station includes signal 3, signal 4, signal 5, signal 1, and signal 2; if the candidate offset parameter is -2, the initial frequency domain received signal received by the base station includes signal 4, signal 5, signal 1, and signal 2; if the candidate offset parameter is 0, the initial frequency domain received signal received by the base station includes signal 3, signal 4, signal 5, signal 1, and signal 2; if the candidate offset parameter is 1, the initial frequency domain received signal received by the base station includes signal 3, signal 4, signal 5, and signal 1; if the candidate offset parameter is 2, the initial frequency domain received signal received by the base station includes signal 3, signal 4, and signal 5.

[0080] In step S202 above, the target frequency domain received signal corresponding to each initial frequency domain received signal can be obtained by performing a phase-rotation cancellation process on each initial frequency domain received signal corresponding to the candidate offset parameter. It is understood that one candidate offset parameter can also correspond to multiple target frequency domain received signals.

[0081] It should be noted that the embodiments of this application do not impose specific limitations on the specific implementation method for determining the target frequency domain received signal, and those skilled in the art can make appropriate adjustments according to the actual situation. For example, if the terminal uses a time delay sequence to perform phase rotation processing on the initial frequency domain transmitted signal, the base station can also use a time delay sequence to perform phase rotation cancellation processing on the initial frequency domain received signal.

[0082] In S203 above, as mentioned earlier, the initial frequency domain received signal corresponding to each candidate offset parameter is different, that is, the target frequency domain received signal corresponding to each candidate offset parameter is different. Therefore, residual time delay can be estimated based on multiple target frequency domain received signals corresponding to the candidate offset parameter, thereby obtaining the time domain combining correlation waveform corresponding to the candidate offset parameter.

[0083] For example, conventional PRACH detection and residual delay estimation can be performed on each candidate offset parameter. Specifically, this may include operations such as local sequence conjugate multiplication, frequency domain zero padding, inverse fast Fourier transform (IFFT), and superposition of PRACH time-domain correlation waveforms at different repetition positions. These processing procedures are the same as those in existing technologies, and then the time-domain merged correlation waveform corresponding to each candidate offset parameter can be obtained.

[0084] It is understood that, compared with receiving signals in the entire target frequency domain, the residual delay estimation method provided in this application embodiment can improve the accuracy of residual delay estimation.

[0085] In the above S204, during the process of traversing the candidate offset parameters, if the candidate offset parameters are consistent with the true values, the frequency domain phase rotation effect at the transmitting end is canceled out. In the subsequent detection process, the time-domain correlation waveforms at different PRACH repetition positions have the same shape. After being superimposed, the correlation peaks overlap to obtain a merging gain, ensuring that the detection performance is the same as that of the prior art. If the candidate offset parameters are inconsistent with the true values, the peak values ​​of the time-domain correlation waveforms at different PRACH repetition positions will be staggered in the subsequent detection process. After being superimposed, a merging gain cannot be obtained, and the correlation peaks are relatively small.

[0086] Based on the above results, by determining the candidate offset parameter with the largest peak value among multiple candidate offset parameters and their time-domain combined correlation waveforms as the target offset parameter, the optimal candidate offset parameter is found at the optimal detection decision time based on the magnitude of the correlation peak, thus also identifying the true residual time delay. Therefore, the embodiments of this application can expand the time offset estimation range of the prior art from... Increase to For example: in typical configurations of existing technical solutions In this scenario, the time bias estimation range is expanded by 23 times, significantly increasing the system's ability to resist large time biases.

[0087] In the above scheme, during the process of traversing candidate offset parameters, if the candidate offset parameter matches the true value, the phase rotation effect at the terminal is canceled out. In subsequent detection, the time-domain correlation waveforms at different PRACH repetition positions have the same shape, and after superposition, the correlation peaks overlap to obtain a merging gain, ensuring detection performance is the same as existing technologies. If the candidate offset parameter does not match the true value, the peak values ​​of the time-domain correlation waveforms at different PRACH repetition positions will be staggered during subsequent detection, and after superposition, no merging gain can be obtained, resulting in smaller correlation peaks. Therefore, this peak-based screening method can more accurately determine the target offset parameter corresponding to integer multiple offsets, reducing errors caused by improper offset parameter selection. Simultaneously, by canceling phase rotation processing, the signals from each repeated transmission are better aligned in the frequency domain, enhancing signal coherence, improving the reliability of residual time offset estimation, and further optimizing uplink synchronization performance.

[0088] It should be noted that when determining the target offset parameters, the above methods S201-S204 can be used, that is, traversing all candidate offset parameters; or the search range can be narrowed first (for example, by using heuristic algorithms, machine learning models, etc.), and then the target offset parameters can be determined from the narrowed search range.

[0089] In addition, in the process of determining the target offset parameter from multiple candidate offset parameters, besides using the methods described in S203-S204 above, i.e., comparing the peak values ​​of time-domain correlation waveforms, the target offset parameter can also be determined by statistical methods, such as using clustering to determine the target offset parameter, or using a Bayesian estimation model to determine the target offset parameter, etc.

[0090] The following describes a specific implementation method for determining the initial frequency domain received signal corresponding to the candidate offset parameters. Specifically, step S201 may include the following steps:

[0091] S301: If the candidate offset parameter If the value is not less than 0, then the initial frequency domain received signal corresponding to the candidate offset parameter is determined to be the first... The first reception corresponds to the initial frequency domain received signal until the second reception. The initial frequency domain received signal corresponding to the next reception;

[0092] S302: If the candidate offset parameter If the value is less than 0, then the initial frequency domain received signal corresponding to the candidate offset parameter is determined to be the initial frequency domain received signal from the first reception to the second reception. The first reception corresponds to the initial frequency domain received signal.

[0093] As one implementation method, the above-described S301 and S302 can be represented by the following formula:

[0094] ;

[0095] in, For the number of times received, , To receive the total number of times, For the first The first reception corresponds to the initial frequency domain received signal. This is the index of the frequency domain subcarrier, used to identify the specific location of the PRACH signal in the frequency domain. , The length of the initial frequency domain transmitted signal, Candidate offset parameters, .

[0096] It should be noted that S301 and S302 above correspond to two parallel situations, and their execution order is not limited.

[0097] In the above scheme, by clearly defining the initial frequency domain received signal range corresponding to different candidate offset parameters, it is ensured that all valid signals related to the current candidate parameters can be covered during the processing, avoiding signal omission or interference from invalid signals. This makes the evaluation of candidate offset parameters more comprehensive and accurate, thereby improving the effectiveness of the entire residual time offset estimation process.

[0098] The following describes a specific implementation method for determining the target frequency domain received signal corresponding to each initial frequency domain received signal. Specifically, S202 may include the following steps:

[0099] S401: For any repeated transmission, the product of the initial frequency domain received signal and the conjugate of the time delay sequence corresponding to the repeated transmission is determined as the target frequency domain received signal corresponding to the repeated transmission.

[0100] As one implementation method, the above-described S401 can be represented by the following formula:

[0101]

[0102] ;

[0103] in, For the first Secondary reception and candidate offset parameters The corresponding target frequency domain received signal, For the number of times received, , To receive the total number of times, For the first The first reception corresponds to the initial frequency domain received signal. This is the index of the frequency domain subcarrier, used to identify the specific location of the PRACH signal in the frequency domain. , The length of the initial frequency domain transmitted signal, It is a time-delay sequence.

[0104] In this embodiment, the time delay sequence is used to perform phase rotation processing on the initial frequency domain transmitted signal to obtain the target frequency domain transmitted signal. This embodiment does not specifically limit its implementation. For example, the time delay sequence can be generated based on a linear rule; or, it can be generated based on a quadratic function; or, a pseudo-random noise sequence can be used to generate the time delay sequence, etc. As one implementation, the time delay sequence can be represented by the following formula:

[0105] ;

[0106] in, It is a time-delay sequence. The index of the frequency domain subcarrier , The length of the initial frequency domain transmitted signal, For delay parameters, and , For the number of times received, , To receive the total number of times, For configuration parameters and .

[0107] In the above scheme, the phase rotation cancellation processing is achieved by multiplying the initial frequency domain received signal with the conjugate of the corresponding time delay sequence. This effectively eliminates the preset time delay effect introduced by the frequency domain phase rotation of the terminal transmitted signal, and makes the target frequency domain received signal of each repeated transmission maintain better consistency in the frequency domain.

[0108] Furthermore, based on the above embodiments, S103 may specifically include the following steps:

[0109] S501: Perform residual time offset estimation on the initial frequency domain received signal to obtain a fractional offset, and determine an integer offset based on the subcarrier spacing corresponding to the initial frequency domain received signal and the target offset parameter.

[0110] S502: Determine the residual time offset based on the fractional offset and the integer offset.

[0111] For example, the residual time offset can be determined by the following formula:

[0112] ;

[0113] in, For residual time bias, The offset is a fraction of a factor. , The offset is an integer multiple. , The subcarrier spacing corresponding to the PRACH signal. This refers to the target offset parameter.

[0114] In the above scheme, the residual time offset is obtained by separately determining the fractional offset and the integer offset, and then combining the two. This fully utilizes the characteristics of different offset types for targeted estimation. Specifically, the estimation of the fractional offset can be achieved with high-precision calculation using sophisticated signal processing algorithms, while the integer offset is determined by combining the subcarrier spacing and the target offset parameter. Combining the two can improve the accuracy of residual time offset determination.

[0115] Furthermore, based on the above embodiments, the step of estimating the residual time offset of the initial frequency domain received signal in S501 may specifically include the following steps:

[0116] S601: Determine the initial frequency domain received signal corresponding to the target offset parameters.

[0117] S602: Perform residual time offset estimation on the initial frequency domain received signal corresponding to the target offset parameters.

[0118] In the above scheme, since the target offset parameter is the optimal parameter after screening, the estimation accuracy of the fractional offset can be improved by estimating based on its corresponding signal, and then combined with the integer offset to obtain a more accurate residual time offset.

[0119] The following describes a specific implementation of another method for determining residual time offset provided in this application. This method can be executed by a base station, or by components of the base station, such as the base station's processor, chip, chip system, or circuit, or by a logic module or software capable of implementing all or part of the base station's functions. The following description uses the method executed by a base station as an example, and the method specifically includes the following steps:

[0120] S701: Receives multiple initial time-domain received signals.

[0121] S702: Determine the target offset parameter corresponding to the integer multiple offset in the residual time offset of the initial time-domain received signal.

[0122] S703: Determine the residual time offset based on the initial time-domain received signal and the target offset parameters.

[0123] Specifically, in S701 above, multiple initial time-domain received signals correspond one-to-one with time-domain transmitted signals repeatedly sent by the terminal. As mentioned earlier, the terminal can transmit the same time-domain transmitted signal according to the number of repetitions configured by the network. This time-domain transmitted signal is a time-domain signal formed by mapping a frequency-domain signal generated by the terminal based on the subcarrier interval onto consecutive subcarriers. It should be noted that this application embodiment does not specifically limit the specific value of the number of repetitions or the specific generation method of the time-domain transmitted signal; those skilled in the art can make appropriate adjustments according to the actual situation.

[0124] Due to factors such as propagation attenuation, noise interference, and timing errors, the signal received by the base station is often inconsistent with the signal transmitted by the terminal. Therefore, the initial time-domain received signal in S701 refers to the time-domain signal received by the base station, which corresponds to the time-domain signal (i.e., the frequency-domain transmitted signal) transmitted by the terminal. In this embodiment, since the terminal transmits multiple time-domain transmitted signals, the base station also receives multiple initial time-domain received signals, and each initial time-domain received signal corresponds to a time-domain transmitted signal transmitted by the terminal in one transmission.

[0125] The base station receives the aforementioned time-domain transmitted signals according to its preset PRACH reception time-frequency positions. Specifically, the base station predefines specific positions of the PRACH signals in the time domain and frequency domain to form a PRACH resource pool, which is used to listen for and receive PRACH signals sent by the terminal.

[0126] It is understandable that, due to the residual time offset, the time-domain transmitted signal received by the base station according to the aforementioned PRACH receiving time-frequency position may be incomplete; that is, the initial time-domain received signal only includes a portion of the time-domain transmitted signal. Here, the aforementioned residual time offset represents the deviation between the actual time the base station receives the initial time-domain received signal and the time the base station expects to receive the initial time-domain received signal.

[0127] In other words, if the base station's preset PRACH reception time deviates significantly from the actual PRACH arrival time—for example, if this deviation exceeds the duration of a single PRACH signal (which is equal to the reciprocal of the PRACH subcarrier interval)—then the base station will miscount the PRACH repetition positions. For instance, suppose the frequency domain signal corresponding to the time-domain transmission signal sent by the terminal is... The initial frequency domain received signal corresponding to the initial time domain received signal received by the base station is: ,but ,in, For the number of times received, , To receive the total number of times, This is the index of the frequency domain subcarrier, used to identify the specific location of the PRACH signal in the frequency domain. , The length of the initial frequency domain transmitted signal.

[0128] Understandably, since the base station pre-determines the key parameters of the terminal's repeated time-domain transmission signals (e.g., repetition count, repetition time interval, time-domain length of a single signal) through network configuration, the base station can determine a total reception window based on these key parameters. Within this total reception window, the base station receives signals according to the received time-frequency position and performs signal detection on the received signals: by performing correlation operations with the local reference sequence, it determines whether a valid signal exists at that position. When the number of valid signals detected by the base station within the total reception window equals the preset repetition count, it can be considered that the time-domain transmission signals repeatedly transmitted by the terminal have been received, and subsequent steps are executed.

[0129] In S702 above, as mentioned earlier, the residual time offset refers to the deviation between the time when the base station actually receives the initial time-domain received signal and the time when the base station expects to receive the initial time-domain received signal. It can include integer multiple offsets and fractional multiple offsets. Therefore, determining the residual time offset of the base station requires determining the fractional multiple offset, integer multiple offset, and the multiple of the integer multiple offset in the residual time offset.

[0130] The fractional offset can be obtained by estimating the residual time offset of the initial time-domain received signal; the integer offset can be determined according to the subcarrier spacing corresponding to the PRACH signal; the multiple of the integer offset is the target offset parameter in this embodiment, which can be obtained by executing S702.

[0131] It should be noted that the embodiments of this application do not impose specific limitations on the specific implementation methods for determining the above-mentioned target offset parameters, and those skilled in the art can make appropriate adjustments according to the actual situation. For example, the above-mentioned target offset parameters can be determined based on experience; or, the above-mentioned target offset parameters can be determined in advance through experiments; or, the above-mentioned target offset parameters can be determined using a deep learning model; or, the above-mentioned target offset parameters can be determined by filtering the maximum peak value of the temporally merged related waveforms, etc.

[0132] The specific implementation of S703 described above is similar to the specific implementation of S103 in the previous embodiments, and will not be described again here.

[0133] In the above scheme, by separating the integer multiple offset and the fractional multiple offset in the residual time offset, the target offset parameter corresponding to the integer multiple offset is first determined, and then the residual time offset is calculated by combining the initial time domain received signal. This takes into account both the impact of the integer multiple offset on signal synchronization and accurately calculates the fractional multiple offset. Thus, while ensuring the performance of PRACH detection and time offset estimation, the estimation range of the residual time offset in the prior art can be expanded, thereby effectively reducing the error of residual time offset estimation in the prior art.

[0134] The following describes a specific implementation method for determining target offset parameters provided by an embodiment of this application. In this implementation method, before transmitting a time-domain transmission signal, the terminal can first perform phase rotation processing on the initial frequency-domain transmission signal to obtain a target frequency-domain transmission signal, and then perform inverse Fourier transform on the target frequency-domain transmission signal to obtain a time-domain transmission signal. Correspondingly, the base station can perform phase rotation cancellation processing on the initial time-domain received signal to select the target candidate offset parameter that makes the peak value of the time-domain merged related waveform the largest from multiple candidate offset parameters, thereby determining the residual time offset.

[0135] It is understandable that performing phase rotation on a frequency domain signal is equivalent to performing a cyclic shift on a time domain signal; correspondingly, performing phase rotation cancellation on a frequency domain signal is equivalent to performing cyclic shift cancellation on a time domain signal. As one implementation method, phase rotation on the frequency domain signal can be achieved by multiplying it by a time delay sequence; alternatively, phase rotation cancellation on the frequency domain signal can be achieved by performing cyclic shift cancellation on the time domain signal.

[0136] At this point, the above-mentioned S702 may specifically include the following steps:

[0137] S801: For each candidate offset parameter, determine the initial time-domain received signal corresponding to that candidate offset parameter.

[0138] S802 performs phase-rotation cancellation processing on each initial time-domain received signal corresponding to the candidate offset parameter to obtain the target time-domain received signal corresponding to each initial time-domain received signal.

[0139] S803: Based on the multiple target time-domain received signals corresponding to the candidate offset parameter, perform residual time delay estimation to obtain the time-domain merging correlation waveform corresponding to the candidate offset parameter.

[0140] S804: Determine the candidate offset parameter with the largest peak value of the time-domain merged correlation waveform among multiple candidate offset parameters as the target offset parameter.

[0141] Specifically, in determining the residual time offset, since the base station does not know the magnitude of the integer multiple offset, it is necessary to select a candidate offset parameter from multiple candidate offset parameters as the target offset parameter. It should be noted that this application does not impose specific limitations on the specific values ​​of the candidate offset parameter; those skilled in the art can make appropriate adjustments based on actual circumstances. As one implementation method, ,in, Candidate offset parameters, The total number of times to send (i.e., the total number of times to receive), for example: when When the offset parameter can be -2, -1, 0, 1, or 2, the candidate offset parameter can be -2, -1, 0, 1, or 2.

[0142] It is understood that the candidate offset parameter should be an integer. A positive integer candidate offset parameter indicates a delay between the actual time the base station receives the initial time-domain received signal and the expected time. A negative integer candidate offset parameter indicates an advance between the actual time the base station receives the initial time-domain received signal and the expected time. A candidate offset parameter of 0 indicates that there is no integer multiple offset between the actual time the base station receives the initial time-domain received signal and the expected time.

[0143] As mentioned earlier, due to residual time offset, the time-domain transmitted signal received by the base station may be incomplete; that is, the initial time-domain received signal only includes a portion of the time-domain transmitted signal. In S801 above, since the residual time offset corresponding to each candidate offset parameter is different, the initial time-domain transmitted signal received by the base station is different for each candidate offset parameter. It can be understood that one candidate offset parameter can correspond to multiple initial time-domain received signals.

[0144] For example, suppose the initial frequency domain transmitted signal includes signal 1, signal 2, signal 3, signal 4, and signal 5, and the target frequency domain transmitted signal obtained after phase rotation processing includes signal 3, signal 4, signal 5, signal 1, and signal 2. Then: if the candidate offset parameter is -2, the initial frequency domain received signal received by the base station includes signal 5, signal 1, and signal 2; if the candidate offset parameter is -1, the initial frequency domain received signal received by the base station includes signal 3, signal 4, signal 5, signal 1, and signal 2; if the candidate offset parameter is -2, the initial frequency domain received signal received by the base station includes signal 4, signal 5, signal 1, and signal 2; if the candidate offset parameter is 0, the initial frequency domain received signal received by the base station includes signal 3, signal 4, signal 5, signal 1, and signal 2; if the candidate offset parameter is 1, the initial frequency domain received signal received by the base station includes signal 3, signal 4, signal 5, and signal 1; if the candidate offset parameter is 2, the initial frequency domain received signal received by the base station includes signal 3, signal 4, and signal 5.

[0145] In step S702 above, the target time-domain received signal corresponding to each initial time-domain received signal can be obtained by performing phase-rotation cancellation processing on each initial time-domain received signal corresponding to the candidate offset parameter. It is understood that one candidate offset parameter can also correspond to multiple target time-domain received signals.

[0146] It should be noted that the embodiments of this application do not specifically limit the specific implementation method for determining the target time-domain received signal, and those skilled in the art can make appropriate adjustments according to the actual situation. For example, if the terminal uses a time delay sequence to perform phase rotation processing on the initial frequency-domain transmitted signal, the base station can perform cyclic shift processing or linear shift processing on the initial time-domain received signal. Wherein, if cyclic shift processing is performed on the initial time-domain received signal, the length of the target time-domain received signal is fixed; if linear shift processing is performed on the initial time-domain received signal, the length of the target time-domain received signal changes with the candidate offset parameter, and the change law can be referred to the formula description in S501, that is, the number of truncated symbols is different.

[0147] In S803 above, residual delay estimation can be performed based on multiple target time-domain received signals corresponding to the candidate offset parameter, thereby obtaining the time-domain combining correlation waveform corresponding to the candidate offset parameter. It is understood that, compared with using all target time-domain received signals, the residual delay estimation method provided in this application embodiment can improve the accuracy of residual delay estimation.

[0148] In the above S804, during the process of traversing the candidate offset parameters, if the candidate offset parameters are consistent with the true values, the frequency domain phase rotation effect at the transmitting end is canceled out. In the subsequent detection process, the time domain correlation waveforms at different PRACH repetition positions have the same shape. After being superimposed, the correlation peaks overlap to obtain a merging gain, ensuring that the detection performance is the same as that of the prior art. If the candidate offset parameters are inconsistent with the true values, the peak values ​​of the time domain correlation waveforms at different PRACH repetition positions will be staggered in the subsequent detection process. After being superimposed, a merging gain cannot be obtained, and the correlation peaks are relatively small.

[0149] Based on the above results, by determining the candidate offset parameter with the largest peak value among multiple candidate offset parameters and their time-domain combined correlation waveforms as the target offset parameter, the optimal candidate offset parameter is found at the optimal detection decision time based on the magnitude of the correlation peak, thus also identifying the true residual time delay. Therefore, the embodiments of this application can expand the time offset estimation range of the prior art from... Increase to For example: in typical configurations of existing technical solutions In this scenario, the time bias estimation range is expanded by 23 times, significantly increasing the system's ability to resist large time biases.

[0150] As can be seen, the method for determining the residual time offset in this embodiment differs from that in the previous embodiment only in that the method for determining the residual time offset in this embodiment cancels the frequency domain phase rotation effect of the transmitter in the time domain, while the method for determining the residual time offset in the previous embodiment cancels the frequency domain phase rotation effect of the transmitter in the frequency domain.

[0151] In the above scheme, during the process of traversing candidate offset parameters, if the candidate offset parameter matches the true value, the phase rotation effect at the terminal is canceled out. In subsequent detection, the time-domain correlation waveforms at different PRACH repetition positions have the same shape, and after superposition, the correlation peaks overlap to obtain a merging gain, ensuring detection performance is the same as existing technologies. If the candidate offset parameter does not match the true value, the peak values ​​of the time-domain correlation waveforms at different PRACH repetition positions will be staggered during subsequent detection, and after superposition, no merging gain can be obtained, resulting in smaller correlation peaks. Therefore, this peak-based screening method can more accurately determine the target offset parameter corresponding to integer multiple offsets, reducing errors caused by improper offset parameter selection. Simultaneously, by canceling phase rotation processing, the signals from each repeated transmission are better aligned in the frequency domain, enhancing signal coherence, improving the reliability of residual time offset estimation, and further optimizing uplink synchronization performance.

[0152] It should be noted that when determining the target offset parameters, the above methods S201-S204 can be used, that is, traversing all candidate offset parameters; or the search range can be narrowed first (for example, by using heuristic algorithms, machine learning models, etc.), and then the target offset parameters can be determined from the narrowed search range.

[0153] In addition, in the process of determining the target offset parameter from multiple candidate offset parameters, besides using the methods described in S803-S804 above, i.e., comparing the peak values ​​of time-domain correlation waveforms, the target offset parameter can also be determined by statistical methods, such as using clustering to determine the target offset parameter, or using a Bayesian estimation model to determine the target offset parameter, etc.

[0154] Please refer to Figure 2 , Figure 2 This application provides a flowchart of a method for determining a time-domain transmitted signal. This method can be executed by a terminal, or by components of the terminal, such as the terminal's processor, chip, chip system, or circuitry. It can also be implemented by a logic module or software capable of performing all or part of the terminal's functions. The following description uses the method executed by a terminal as an example. Specifically, this method may include the following steps:

[0155] S901: Acquire the initial frequency domain transmission signal.

[0156] S902: For any repeated transmission, perform phase rotation processing on the initial frequency domain transmission signal corresponding to that repeated transmission to obtain the target frequency domain transmission signal corresponding to that repeated transmission.

[0157] S903: Generate a time-domain transmission signal corresponding to the repeated transmission based on the target frequency-domain transmission signal, and transmit the time-domain transmission signal in the repeated transmission.

[0158] Specifically, in S901 above, the terminal determines the predetermined subcarrier frequency of PRACH based on the system information broadcast by the base station; based on the subcarrier interval, the terminal generates a frequency domain signal of the PRACH preamble sequence and maps it onto consecutive subcarriers to form an initial frequency domain transmission signal.

[0159] In S902 above, the terminal transmits the same initial frequency domain transmission signal the number of repetitions configured by the network. For any repetition, the initial frequency domain transmission signal can be phase-rotated to the corresponding repetition to obtain the target frequency domain transmission signal corresponding to that repetition.

[0160] This application does not limit the specific implementation method for determining the target frequency domain transmission signal, and those skilled in the art can make appropriate adjustments according to the actual situation. For example, a time delay sequence can be used to perform phase rotation processing on the initial frequency domain transmission signal.

[0161] As one implementation method, the terminal can perform cyclic delay shifting processing on PRACH signals at different repetitive transmission positions according to a given rule, so that the delay values ​​at different repetitive transmission positions are different.

[0162] In the above scheme, the terminal generates the target frequency domain transmission signal by performing phase rotation processing on the initial frequency domain transmission signal, and then converts it into a time domain transmission signal for repeated transmission. This allows the base station to find the optimal target offset parameter by canceling the phase rotation effect after receiving the time domain transmission signal. This expands the estimation range of residual time offset in the prior art while ensuring the performance of PRACH detection and time offset estimation, thereby effectively reducing the error of residual time offset estimation in the prior art.

[0163] The specific implementation method for determining the target frequency domain transmission signal is described below. The above-mentioned S702 may specifically include the following steps:

[0164] S1001: Generate the time delay sequence corresponding to this repeated transmission based on the time delay parameters corresponding to this repeated transmission and the length of the initial frequency domain transmitted signal.

[0165] S1002: The product between the initial frequency domain transmitted signal and the time delay sequence is determined as the target frequency domain transmitted signal.

[0166] Specifically, in S1001 above, the time delay sequence is used to perform phase rotation processing on the initial frequency domain transmission signal to obtain the target frequency domain transmission signal. This application embodiment does not specifically limit its implementation. As one implementation, the time delay sequence can be represented by the following formula:

[0167] ;

[0168] Among them, among them, It is a time-delay sequence. The index of the frequency domain subcarrier and , The length of the initial frequency domain transmitted signal, For delay parameters, and , For the number of times received, , To receive the total number of times, For configuration parameters and .

[0169] The above formula can guarantee that as long as the candidate offset parameter is not equal to the actual offset parameter, the temporal correlation peaks at different PRACH repetition positions will be staggered, thereby ensuring that the embodiments of this application can achieve optimal decision performance.

[0170] In S1002 above, the target frequency domain transmitted signal can be determined using the following formula:

[0171] ;

[0172] in, To transmit signals in the target frequency domain, For the initial frequency domain transmitted signal, It is a time-delay sequence. , To receive the total number of times, This is the index of the frequency domain subcarrier, used to identify the specific location of the PRACH signal in the frequency domain. , The length of the initial frequency domain transmitted signal.

[0173] The above formula can be used to... Adding repeated PRACH transmission signals The delay of each PRACH sampling point (the measurable delay range of a single PRACH signal is...) (1 PRACH sampling point).

[0174] In the above scheme, phase rotation processing is achieved by multiplying the initial frequency domain transmitted signal with the time delay sequence. This allows the base station to cancel the phase rotation processing by multiplying the initial frequency domain received signal with the conjugate of the corresponding time delay sequence. This effectively eliminates the preset time delay effect introduced by the frequency domain phase rotation of the terminal transmitted signal, and makes the target frequency domain received signal of each repeated transmission maintain better consistency in the frequency domain.

[0175] Please refer to Figure 3 , Figure 3 This application provides a structural block diagram of an electronic device 1100, comprising at least one processor 1101, at least one communication interface 1102, at least one memory 1103, and at least one communication bus 1104. The communication bus 1104 enables direct communication between these components, the communication interface 1102 facilitates signaling or data communication with other node devices, and the memory 1103 stores machine-readable instructions executable by the processor 1101. When the electronic device 1100 is running, the processor 1101 communicates with the memory 1103 via the communication bus 1104. When the machine-readable instructions are invoked by the processor 1101, the aforementioned method for determining residual time offset or method for determining time-domain transmitted signals is executed.

[0176] As one implementation method, the aforementioned electronic device 1100 can be a terminal, and different terminals can be interconnected via wired or wireless means. Terminals can be widely used in various scenarios, such as Near Field Communication (NFC) device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, and smart cities.

[0177] The terminal may also be referred to as a mobile station (MS), terminal, or terminal equipment, and may include a subscriber unit, cellular phone, smartphone, wireless data card, personal digital assistant (PDA) computer, tablet computer, handheld modem, laptop computer, cordless phone, wireless local loop (WLL) station, machine type communication (MTC) terminal, etc. For ease of description, all devices mentioned above are referred to as terminals in all embodiments of this application.

[0178] The aforementioned terminal may further include an antenna and a transceiver. The transceiver modulates (e.g., analog-to-digital conversion, filtering, amplification, and up-conversion) the output sample and generates an uplink signal, which is transmitted to the network device via the antenna. On the downlink, the antenna receives the downlink signal transmitted by the network device, and the transceiver modulates (e.g., filtering, amplification, down-conversion, and digitization) the signal received from the antenna and provides input sampling. The processor 1101 is used to execute the residual time offset determination method or the time-domain transmitted signal determination method described in the above embodiments. The embodiments of this application do not limit the specific technology or specific device form used in the terminal.

[0179] In another implementation, the aforementioned electronic device 1100 can be a base station, and the terminal can connect to the base station wirelessly. The base station can also connect to or transmit information with Evolved Universal Terrestrial Radio Access (E-UTRA), New Radio (NR), and future radio access systems or WiFi systems as defined in the 3rd Generation Partnership Project (3GPP). The base station can also connect to devices from two or more of the aforementioned different radio access systems. The base station can also connect to an Open Radio Access Network (O-RAN).

[0180] Base stations may be configured with modules for implementing base station functions. These modules can perform the functions of the following devices: base station, evolved NodeB (eNodeB or eNB), transmission reception point (TRP), next-generation NodeB (gNB) in 5th generation (5G) mobile communication systems, next-generation base station in 6th generation (6G) mobile communication systems, base station in future mobile communication systems, or access node in WiFi systems.

[0181] The aforementioned base station may also include an antenna and a transceiver. In the uplink, the uplink signal from the terminal is received via the antenna, mediated by the transceiver, and further processed by the processor 1101 to recover the signaling information sent by the terminal; in the downlink, the signaling message is processed by the processor 1101, mediated by the transceiver to generate a downlink signal, and transmitted to the terminal via the antenna. The processor 1101 is also used to execute the residual time offset determination method or the time-domain transmitted signal determination method as described in the above embodiments. The base station may include a macro base station, a micro base station or an indoor station, or a relay node or a source base station.

[0182] It is understood that the above only describes a simplified design of the base station. In practical applications, the base station may include any number of transmitters, receivers, processors, controllers, memory, communication units, etc., and all base stations that can implement this application are within the protection scope of this application.

[0183] The processor 1101 comprises one or more, and can be an integrated circuit chip with signal processing capabilities. The processor 1101 can be a general-purpose processor, including a Central Processing Unit (CPU), a Microcontroller Unit (MCU), a Network Processor (NP), or other conventional processors; it can also be a special-purpose processor, including a Neural-network Processing Unit (NPU), a Graphics Processing Unit (GPU), a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. Furthermore, when there are multiple processors 1101, some can be general-purpose processors, and others can be special-purpose processors.

[0184] The memory 1103 includes one or more, which may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0185] This application also provides a computer-readable storage medium that stores computer program instructions. When the computer program instructions are executed by a computer, the computer performs various functions or steps in the above-described methods for determining residual time offset or determining time-domain transmitted signals.

[0186] This application also provides a computer program product that, when run on a computer, causes the computer to execute the various functions or steps in the above-described methods for determining residual time offset or determining time-domain transmitted signals.

[0187] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0188] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0189] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0190] It should be noted that if the function is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0191] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0192] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method of determining residual time offset, characterized by, Applied to a base station, comprising: Receiving a plurality of initial time domain received signals, and determining a corresponding initial frequency domain received signal according to each initial time domain received signal, wherein the plurality of initial time domain received signals correspond one by one to time domain transmitted signals repeatedly transmitted by a terminal multiple times, the time domain transmitted signal is obtained by inverse Fourier transform on a target frequency domain transmitted signal, and the target frequency domain transmitted signal is obtained by phase rotation processing on an initial frequency domain transmitted signal; Determining a target offset parameter corresponding to an integer multiple offset in a residual time offset of the initial time domain received signal, wherein the residual time offset represents a deviation between an actual time of receiving the initial time domain received signal and an expected time of receiving the initial time domain received signal, and the residual time offset includes the integer multiple offset and a decimal multiple offset; Determining the residual time offset according to the initial frequency domain received signal and the target offset parameter; The determination of the residual time offset according to the initial frequency domain received signal and the target offset parameter comprises: Residual time offset estimation is performed on the initial frequency domain received signal to obtain the decimal multiple offset, and the integer multiple offset is determined according to a subcarrier interval corresponding to the initial frequency domain received signal and the target offset parameter; The residual time offset is determined according to the decimal multiple offset and the integer multiple offset; Wherein, the residual time offset is determined by the following formula: ； wherein, is a residual timing offset, is a fractional offset, , is an integer offset, , is a subcarrier spacing corresponding to the PRACH signal, is a target offset parameter.

2. The method for determining the residual time offset according to claim 1, wherein, The determination of the target offset parameter corresponding to the integer multiple offset in the residual time offset of the initial time domain received signal comprises: For each candidate offset parameter, an initial frequency domain received signal corresponding to the candidate offset parameter is determined; Each initial frequency domain received signal corresponding to the candidate offset parameter is subjected to cancellation phase rotation processing to obtain a target frequency domain received signal corresponding to each initial frequency domain received signal; Residual time delay estimation is performed on a plurality of target frequency domain received signals corresponding to the candidate offset parameter to obtain a time domain combined correlation waveform corresponding to the candidate offset parameter; A candidate offset parameter with a maximum peak value of the time domain combined correlation waveform in a plurality of candidate offset parameters is determined as the target offset parameter.

3. A method of determining residual time offset according to claim 2, characterized in that, The determination of the initial frequency domain received signal corresponding to the candidate offset parameter comprises: If the candidate offset parameter If the value is not less than 0, then the initial frequency domain received signal corresponding to the candidate offset parameter is determined to be the first... The first reception corresponds to the initial frequency domain received signal until the second reception. The initial frequency domain received signal corresponding to the next reception, wherein... To receive the total number of times, ; If the candidate offset parameter is less than 0, it is determined that the initial frequency domain received signal corresponding to the candidate offset parameter is the initial frequency domain received signal corresponding to the first reception to the initial frequency domain received signal corresponding to the nth reception. is less than 0, it is determined that the initial frequency domain received signal corresponding to the candidate offset parameter is the initial frequency domain received signal corresponding to the first reception to the initial frequency domain received signal corresponding to the nth reception.

4. The method of determining residual timing offset according to claim 2, characterized in that, The cancellation phase rotation processing of each initial frequency domain received signal corresponding to the candidate offset parameter to obtain a target frequency domain received signal corresponding to each initial frequency domain received signal comprises: For an initial frequency domain received signal corresponding to each repeated transmission, a product between the initial frequency domain received signal and a conjugate of a time delay sequence corresponding to the repeated transmission is determined as the target frequency domain received signal corresponding to the repeated transmission, wherein the time delay sequence is used for phase rotation processing on the initial frequency domain transmitted signal to obtain the target frequency domain transmitted signal.

5. The method of determining residual timing offset according to claim 1, characterized in that, The residual time offset estimation on the initial frequency domain received signal comprises: Determining an initial frequency domain received signal corresponding to the target offset parameter; Residual time offset estimation is performed on the initial frequency domain received signal corresponding to the target offset parameter.

6. A method of determining a residual time offset, characterized by Applied to a base station, comprising: receiving a plurality of initial time domain received signals, wherein the plurality of initial time domain received signals correspond to time domain transmission signals repeatedly transmitted by a terminal, the time domain transmission signals are obtained by inverse Fourier transform on target frequency domain transmission signals, and the target frequency domain transmission signals are obtained by phase rotation processing on initial frequency domain transmission signals; determining a target offset parameter corresponding to an integer multiple offset in a residual time offset of the initial time domain received signals, wherein the residual time offset represents a deviation between an actual time of receiving the initial time domain received signals and an expected time of receiving the initial time domain received signals, and the residual time offset includes the integer multiple offset and a decimal multiple offset; determining the residual time offset according to the initial time domain received signals and the target offset parameter; the determining the residual time offset according to the initial time domain received signals and the target offset parameter includes: performing residual time offset estimation on the initial time domain received signals to obtain the decimal multiple offset, and determining the integer multiple offset according to a subcarrier interval corresponding to the initial time domain received signals and the target offset parameter; determining the residual time offset according to the decimal multiple offset and the integer multiple offset; wherein the residual time offset is determined by the following formula: ； wherein, is a residual timing offset, is a fractional offset, , is an integer offset, , is a subcarrier spacing corresponding to the PRACH signal, is a target offset parameter.

7. The method of claim 6, wherein the determining a target offset parameter corresponding to an integer multiple offset in a residual time offset of the initial time domain received signals includes: for each candidate offset parameter, determining the initial time domain received signals corresponding to the candidate offset parameter; performing cancellation phase rotation processing on each initial time domain received signal corresponding to the candidate offset parameter to obtain a target time domain received signal corresponding to each initial time domain received signal; performing residual time delay estimation on a plurality of target time domain received signals corresponding to the candidate offset parameter to obtain a time domain combined correlation waveform corresponding to the candidate offset parameter; determining a candidate offset parameter with a maximum peak value of the time domain combined correlation waveform in a plurality of candidate offset parameters as the target offset parameter. applied to a terminal, including:

8. A method of determining a time-domain transmit signal, characterized by obtaining an initial frequency domain transmission signal; for any repeated transmission, performing phase rotation processing on the initial frequency domain transmission signal corresponding to the repeated transmission to obtain a target frequency domain transmission signal corresponding to the repeated transmission; generating a time domain transmission signal corresponding to the repeated transmission according to the target frequency domain transmission signal, and transmitting the time domain transmission signal in the repeated transmission; the performing phase rotation processing on the initial frequency domain transmission signal corresponding to the repeated transmission includes: generating a time delay sequence corresponding to the repeated transmission according to a time delay parameter corresponding to the repeated transmission and a length of the initial frequency domain transmission signal; determining a product between the initial frequency domain transmission signal and the time delay sequence as the target frequency domain transmission signal; the generating the time delay sequence corresponding to the repeated transmission according to the time delay parameter corresponding to the repeated transmission and the length of the initial frequency domain transmission signal includes: determining the time delay sequence by the following formula: ​ ； wherein is the time delay sequence, is the index of the frequency domain subcarrier and , is the length of the initial frequency domain transmit signal, is the time delay parameter, and , is the number of receptions, , is the total number of receptions, is the configuration parameter and .

9. A computer program product, characterised in that, comprising computer program instructions, which, when read and executed by a processor, perform the method of any one of claims 1-8.

10. An electronic device, comprising: comprising: a processor, a memory and a bus; the processor and the memory communicate with each other through the bus; the memory stores computer program instructions executable by the processor, and the processor invoking the computer program instructions can perform the method of any one of claims 1-8.

11. A computer readable storage medium, characterized in that, The computer readable storage medium stores computer program instructions, which, when executed by a computer, cause the computer to perform the method of any one of claims 1-8.

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