A kind of almanac auxiliary-based PSS coarse synchronization method, device and medium

Abstract

The present application relates to a kind of almanac auxiliary-based PSS coarse synchronization method, equipment and medium, wherein, method includes: obtaining almanac data or ephemeris information, and the position speed information of terminal device;Parameter extrapolation is calculated based on the almanac data, and the ephemeris data of required time is obtained, and the component of satellite speed in signal propagation direction is calculated in combination with the position speed information and the Doppler shift caused by satellite movement;According to the Doppler shift caused by satellite movement, the preset frequency offset range in PSS signal search process is calculated in combination with subcarrier spacing;Based on the preset frequency offset range, the detection process of synchronization signal block is carried out.The present application can reduce the complexity of PSS blind search link and time-frequency offset estimation.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a PSS coarse synchronization method, device and medium based on calendar assistance. Background Technology

[0002] The primary synchronization signal (PSS signal) is contained within the synchronization signal block (SSB). Terminals rely on the PSS of the SSB and the auxiliary synchronization signal (SSS signal) to achieve time-frequency synchronization during access. In traditional terrestrial 5G, terminals detect the SSB through blind search (time-frequency scanning). However, in satellite communication, this method is inefficient due to the following challenges: 1. In satellite communication systems, there is high-speed relative motion between the ground terminal and the satellite, leading to significant frequency offset. Low Earth orbit (LEO) satellites can have relative speeds up to 7 km / s, resulting in frequency offsets of ±720 kHz. SSBs have different periods, with the protocol supporting a maximum period of 5-160 ms. The rate of frequency offset variation varies depending on the satellite elevation angle. Always choosing the maximum period as the blind search duration is not optimal. 2. Satellite beams move rapidly, resulting in short coverage times. Some LEO satellites have less than 10 minutes of visible time, causing frequent cell handovers. From an energy-saving perspective, after powering on, the user terminal (UE) should first determine whether access is suitable based on information such as satellite coverage and beam pointing, rather than immediately starting a blind search for signals. 3. Wide-area coverage results in low SSB density (satellite beams are sparser than terrestrial macro stations). 4. Using a preset frequency offset to perform a blind search for the maximum period SSB signal involves a huge amount of computation. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a PSS coarse synchronization method, device, equipment and medium based on almanac assistance, which can reduce the complexity of PSS blind search and time-frequency offset estimation.

[0004] The technical solution adopted by this invention to solve its technical problem is: to provide a PSS coarse synchronization method based on calendar assistance, including the following steps:

[0005] Acquire almanac data or ephemeris information, as well as the location and speed information of the terminal device;

[0006] Based on the almanac data, parameter extrapolation calculations are performed to obtain the ephemeris data for the required time. The satellite velocity component in the signal propagation direction and the Doppler shift caused by the satellite motion are then calculated in combination with the position and velocity information.

[0007] Based on the Doppler frequency shift caused by the satellite motion, the preset frequency offset range during the PSS signal search process is calculated in combination with the subcarrier spacing;

[0008] The detection process for synchronization signal blocks is based on the preset frequency offset range.

[0009] The almanac data or ephemeris information is in any of the following forms:

[0010] The satellite almanac data was cached during the last shutdown or was pre-stored at the factory.

[0011] The ephemeris information updated during the previous access and the ephemeris information does not exceed the validity period;

[0012] Ephemeris information obtained by the terminal device with the help of the ground base station before initial access;

[0013] Satellite operators pre-distribute ephemeris information via satellite or terrestrial internet.

[0014] The step of extrapolating parameters based on the almanac data to obtain the ephemeris data for the required time specifically includes:

[0015] The satellite's position and velocity within its orbital plane at the required time are determined based on the almanac data.

[0016] Using a coordinate transformation matrix, the satellite's position and velocity in the orbital plane at the required time are transformed to ECEF coordinates, resulting in the satellite's ECEF coordinate values ​​and velocity vector in the ECEF coordinate system.

[0017] The determination of the satellite's position and velocity within its orbital plane at the desired time based on the almanac data specifically includes:

[0018] Calculate the extrapolated duration based on the required time and the almanac reference time;

[0019] The average angular velocity of the satellite is determined based on the semi-major axis of the satellite's orbit at the time referenced in the almanac.

[0020] Multiply the extrapolated duration and the average angular velocity of the satellite, and add the mean anomaly angle of the ephemeris reference time to obtain the mean anomaly angle of the desired time.

[0021] The off-center angle is obtained by iterative solution based on the mean anterior angle and the orbital eccentricity at the required time.

[0022] The true anomaly angle is calculated based on the deviated anomaly angle and the orbital eccentricity, and the latitudinal argument is obtained by combining the perigee argument.

[0023] Calculate the orbital radius based on the aforementioned anomalous point angle, orbital eccentricity, and the semi-major axis of the satellite orbit;

[0024] Multiply the difference between the rate of change of the ascending node longitude and the Earth's rotational angular velocity by the extrapolated time, and add the ascending node longitude at the ephemeris reference time to obtain the rate of change of the ascending node longitude at the desired time.

[0025] The satellite's position within the orbital plane at the desired time is calculated based on the latitude argument and the orbital in-plane radius.

[0026] The satellite's velocity at the required time is calculated based on the latitude argument, the orbital radius, and the difference between the rate of change of longitude at the ascending node and the Earth's rotational angular velocity.

[0027] The component of the satellite velocity in the signal propagation direction is represented as: The Doppler frequency shift caused by the satellite motion is expressed as: ,in, Let $\frac{ ... This refers to the location information of the terminal device. These are the ECEF coordinates of the satellite. Let V be the velocity vector of the satellite in the ECEF coordinate system. The Doppler shift caused by satellite motion For downlink carrier frequency, It is the speed of light.

[0028] The preset frequency offset range during the PSS signal search process is expressed as follows: ,in, This is the preset frequency offset range during the PSS signal search process. The Doppler shift caused by satellite motion The subcarrier spacing.

[0029] The detection process for the synchronization signal block based on the preset frequency offset range specifically includes:

[0030] Based on the preset frequency offset range, a preset frequency offset is added to the three sets of local sequences to obtain multiple sets of local sequences with preset frequency offsets;

[0031] The received signal sequence is downsampled and filtered;

[0032] Calculate the sliding correlation values ​​between multiple sets of local sequences with preset frequency offsets and the downsampled and filtered signal sequences;

[0033] The integer multiple frequency offset and coarse time offset are obtained by using the sliding correlation value decision. The integer multiple frequency offset is the preset frequency offset of the local sequence corresponding to the effective sliding correlation value. The coarse time offset is the data offset of the data index corresponding to the peak value of the effective sliding correlation value converted to the original sampling rate.

[0034] The preset frequency offset is represented as: ,in, This is the preset frequency offset range during the PSS signal search process. For subcarrier spacing, It is a natural number.

[0035] The technical solution adopted by the present invention to solve its technical problem is: to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-mentioned calendar-assisted PSS coarse synchronization method.

[0036] The technical solution adopted by the present invention to solve its technical problem is: to provide a computer-readable storage medium on which a computer program is stored, wherein the computer program, when executed by a processor, implements the steps of the above-mentioned calendar-assisted PSS coarse synchronization method.

[0037] Beneficial effects

[0038] By adopting the above-mentioned technical solution, this invention has the following advantages and positive effects compared with the prior art: This invention uses almanac / ephemeris data and terminal position and velocity information to perform orbit extrapolation and Doppler frequency shift pre-calculation, eliminating the need for blind frequency offset search across the entire range during the initial access phase. This significantly reduces the computational complexity and workload of PSS coarse synchronization, improving synchronization efficiency. Furthermore, this invention dynamically limits the frequency offset search range based on predicted Doppler frequency shift and subcarrier spacing, replacing the traditional full-frequency domain scanning method, effectively shortening the synchronization signal block detection time, and adapting to scenarios with high-speed movement of low-orbit satellites, short beam coverage duration, and frequent cell handover. This invention can complete satellite position, velocity, and frequency offset prediction before access, reducing terminal invalid signal search and power consumption, and improving the initial access success rate and stability of satellite communication terminals in wide-area coverage and low SSB density scenarios. The entire process does not require waiting for synchronization to be completed before parsing the SIB to obtain high-precision ephemeris, achieving pre-synchronization assisted coarse synchronization. This breaks through the technical limitations of traditional satellite communication initial access time and frequency synchronization relying on blind search, and is compatible with various data acquisition methods such as pre-stored almanacs, cached ephemeris, and ground base station assistance, making it more applicable. Attached Figure Description

[0039] Figure 1 This is a flowchart of the PSS coarse synchronization method based on calendar assistance according to the first embodiment of the present invention. Detailed Implementation

[0040] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0041] The first embodiment of the present invention relates to a coarse synchronization method for PSS based on an almanac, such as... Figure 1 As shown, it includes the following steps:

[0042] Step 1: Obtain almanac data or ephemeris information, as well as the location and speed information of the terminal device.

[0043] The methods for obtaining almanac data or ephemeris information in this step include, but are not limited to: 1. Satellite almanac data cached during the last power-off or pre-stored at the factory. 2. Ephemeris data updated during the previous access that does not exceed the validity period. 3. In satellite-terrestrial fusion scenarios, the UE obtains ephemeris data using a ground base station before initial access and then switches to satellite mode. 4. Satellite operators pre-distribute ephemeris data through other links (such as broadcast satellites and terrestrial internet). 5. In future technological evolution, the UE can obtain valid ephemeris data before access. The methods for obtaining the location and velocity information of the terminal device include, but are not limited to: 1. Using a terminal with GNSS capabilities to obtain location and velocity using GNSS positioning capabilities. 2. Terminal devices without GNSS capabilities can obtain their own location and velocity information through ground base station assistance or by extrapolating from historical locations.

[0044] Step 2: Based on the almanac data, perform parameter extrapolation calculations to obtain the ephemeris data for the required time, and combine the position and velocity information to calculate the satellite velocity component in the signal propagation direction and the Doppler shift caused by the satellite motion.

[0045] This step first determines the satellite's position and velocity within its orbital plane at the desired time based on the almanac data. Then, using a coordinate transformation matrix, the satellite's position and velocity within its orbital plane at the desired time are converted to ECEF coordinates, yielding the satellite's ECEF coordinate values ​​and velocity vector in the ECEF coordinate system. This is achieved using the orbital root data from the almanac or ephemeris. Rate of change of longitude of the ascending node Extrapolate to the required time ephemeris data The coordinates and velocity vectors of the ECEF satellite are obtained by performing coordinate transformation. For reference in the almanac, Indicates the semi-major axis of the satellite orbit. It is the orbital eccentricity. For the track inclination angle, Longitude of the ascending node Perimeter argument It is the angle closest to the point.

[0046] Specifically

[0047] First, based on the required time Reference time in calendar Calculate extrapolation duration ,Right now ;

[0048] Next, based on the semi-major axis of the satellite orbit at the time referenced in the almanac. Determine the average angular velocity of the satellite ,Right now , The gravitational constant of Earth;

[0049] Then, based on the extrapolation duration... Satellite mean angular velocity The approximate angle of the time referenced in the almanac Calculate the mean anterior angle at the required time. ,Right now ;

[0050] Then based on the mean anterior angle at the required time and orbital eccentricity The approach angle is obtained through iterative solution. ,Right now ;

[0051] Then, based on the aforementioned near point angle and orbital eccentricity Calculate the true anterior angle ,Right now And combined with perigee argument Obtain the latitudinal argument ,Right now .

[0052] According to the near point angle eccentricity of orbit and the semi-major axis of the satellite orbit Calculate the inner radius of the orbital plane ,Right now ;

[0053] Based on the rate of change of longitude of the ascending node Earth's rotational angular velocity Extrapolation duration And the longitude of the ascending node at the time of reference in the almanac. Calculate the rate of change of longitude of the ascending node at the required time. ,Right now ;

[0054] According to the latitude angle and the inner radius of the orbital plane Calculate the satellite's position within its orbital plane at the desired time. ,Right now ;

[0055] The position of the satellite in the orbital plane at the desired time is determined using a coordinate transformation matrix. Convert to ECEF coordinates to obtain ECEF satellite coordinates. .

[0056] According to the latitude angle The inner radius of the track surface and the rate of change of longitude of the ascending node With the Earth's rotational angular velocity The difference is used to calculate the satellite's velocity at the required time. ,Right now:

[0057] ;

[0058] The satellite's speed at the required time Velocity vector transformed to ECEF coordinate system .

[0059] Assume the terminal device obtains its own location using the positioning system as follows: The component of the satellite's velocity in the direction of signal propagation is Doppler effect caused by satellite motion Represented as: ,in, For downlink carrier frequency, It is the speed of light.

[0060] Step 3: Based on the Doppler frequency shift caused by the satellite motion, and combined with the subcarrier spacing, calculate the preset frequency offset range during the PSS signal search process. The preset frequency offset range during the PSS signal search process in this step is expressed as follows: ,in, This is the preset frequency offset range during the PSS signal search process. The subcarrier spacing.

[0061] Step 4: Detect the synchronization signal block based on the preset frequency offset range. The specific process of this step is as follows:

[0062] First, based on the preset frequency offset range A preset frequency offset is added to the three sets of local sequences to obtain three sets of local sequences with preset frequency offsets. The preset frequency offset is represented as follows: , It is a natural number, and it is recommended to take the value 1.

[0063] Next, the received signal sequence is downsampled and filtered;

[0064] Then, the sliding correlation values ​​between the three sets of local sequences with preset frequency offsets and the downsampled and filtered signal sequences are calculated using the correlation detection method. The correlation calculation method is as follows: , .in, This represents the length of the local sequence after downsampling. This represents the nth local sequence. Indicates the received signal sequence from the index Start extracting length For the sequence. This indicates the total length of the received sequence after downsampling in the buffer.

[0065] Finally, the integer multiple frequency offset and coarse time offset are obtained using the sliding correlation value decision. The integer multiple frequency offset is the preset frequency offset of the local sequence corresponding to the valid sliding correlation value; the coarse time offset is the data offset calculated from the data index corresponding to the peak value of the valid sliding correlation value to the original sampling rate, and the refraction method is as follows: ,in, For coarse, biased. For the data index corresponding to the peak value of the effective sliding correlation value, To reduce the sampling factor, when making a sliding correlation value decision, you can choose a decision scheme where the maximum correlation value is valid or the peak-to-average ratio is greater than a preset threshold.

[0066] The present invention will be further illustrated by a specific embodiment below.

[0067] In this embodiment, upon powering on, the satellite terminal first initiates a cell search process, detecting SSB signals broadcast by the satellite base station at different frequency points. According to this implementation, the terminal first obtains long-term ephemeris data of the satellite using locally cached satellite ephemeris information. Then, it obtains its own position and velocity information based on its GNSS positioning capabilities. Next, the terminal predicts the frequency offset based on the ephemeris extrapolation scheme of this embodiment, assuming a predicted frequency offset of 452 kHz. Since the current SSB subcarrier spacing searched by the UE is 120 kHz, it can be determined that the approximate integer multiple frequency offset is 3 to 5 times the SCS. At this point, the UE can add frequency offsets of 360 kHz, 480 kHz, and 600 kHz to the three sets of local PSS sequences, respectively, resulting in nine sets of local sequences. To further reduce the computational load of the coarse search, the UE first downsamples the received signal, assuming a downsampling factor of 8 times, obtaining the downsampled signal. Then, the nine sets of local sequences are subjected to sliding correlation with the downsampled signal to obtain correlation values. The maximum correlation value (i.e., the maximum peak value) is: The local sequence with the maximum peak value has a preset frequency offset of 480kHz and a mean of [missing value]. The data index for the mean is 539 (counting from 1). Finally, the peak-to-average ratio is used. The decision threshold is compared and can be optimally configured based on the false alarm probability. If the peak-to-average power ratio (PAPR) is greater than the decision threshold, a set of SSB signals is considered to have been detected. The corresponding integer multiple of the frequency offset is 480 kHz, which corresponds to a coarse time offset of the original sampling rate. .

[0068] It is easy to see that this invention uses almanac / ephemeris data and terminal position and velocity information to perform orbit extrapolation and Doppler frequency shift pre-calculation, eliminating the need for blind frequency offset search across the entire range during the initial access phase. This significantly reduces the computational complexity and workload of PSS coarse synchronization, improving synchronization efficiency. Furthermore, this invention dynamically limits the frequency offset search range based on predicted Doppler frequency shift and subcarrier spacing, replacing the traditional full-frequency domain scanning method. This effectively shortens the synchronization signal block detection time and is suitable for scenarios with high-speed movement of low-Earth orbit satellites, short beam coverage duration, and frequent cell handover. This invention can complete satellite position, velocity, and frequency offset prediction before access, reducing terminal invalid signal search and power consumption. It improves the initial access success rate and stability of satellite communication terminals in wide-area coverage and low SSB density scenarios. The entire process does not require waiting for synchronization to be completed before parsing the SIB to obtain high-precision ephemeris, achieving pre-synchronization assisted coarse synchronization. This breaks through the technical limitations of traditional satellite communication initial access time and frequency synchronization relying on blind search. It is compatible with various data acquisition methods such as pre-stored almanacs, cached ephemeris, and ground base station assistance, making it more versatile.

[0069] The second embodiment of the present invention relates to an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the calendar-assisted PSS coarse synchronization method of the first embodiment.

[0070] The third embodiment of the present invention relates to a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the calendar-assisted PSS coarse synchronization method of the first embodiment.

[0071] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0072] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0073] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction methods implemented in a process. Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0074] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0075] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A coarse synchronization method for PSS based on calendar assistance, characterized in that, Includes the following steps: Acquire almanac data or ephemeris information, as well as the location and speed information of the terminal device; Based on the almanac data, parameter extrapolation calculations are performed to obtain the ephemeris data for the required time. The satellite velocity component in the signal propagation direction and the Doppler shift caused by the satellite motion are then calculated in combination with the position and velocity information. Based on the Doppler frequency shift caused by the satellite motion, the preset frequency offset range during the PSS signal search process is calculated in combination with the subcarrier spacing; The detection process for synchronization signal blocks is based on the preset frequency offset range.

2. The PSS coarse synchronization method based on calendar assistance according to claim 1, characterized in that, The almanac data or ephemeris information is in any of the following forms: The satellite almanac data was cached during the last shutdown or was pre-stored at the factory. The ephemeris information updated during the previous access and the ephemeris information does not exceed the validity period; Ephemeris information obtained by the terminal device with the help of the ground base station before initial access; Satellite operators pre-distribute ephemeris information via satellite or terrestrial internet.

3. The PSS coarse synchronization method based on calendar assistance according to claim 1, characterized in that, The step of extrapolating parameters based on the almanac data to obtain the ephemeris data for the required time specifically includes: The satellite's position and velocity within its orbital plane at the required time are determined based on the almanac data. Using a coordinate transformation matrix, the satellite's position and velocity in the orbital plane at the required time are transformed to ECEF coordinates, resulting in the satellite's ECEF coordinate values ​​and velocity vector in the ECEF coordinate system.

4. The PSS coarse synchronization method based on calendar assistance according to claim 3, characterized in that, The determination of the satellite's position and velocity within its orbital plane at the desired time based on the almanac data specifically includes: Calculate the extrapolated duration based on the required time and the almanac reference time; The average angular velocity of the satellite is determined based on the semi-major axis of the satellite's orbit at the time referenced in the almanac. Multiply the extrapolated duration and the average angular velocity of the satellite, and add the mean anomaly angle of the ephemeris reference time to obtain the mean anomaly angle of the desired time. The off-center angle is obtained by iterative solution based on the mean anterior angle and the orbital eccentricity at the required time. The true anomaly angle is calculated based on the deviated anomaly angle and the orbital eccentricity, and the latitudinal argument is obtained by combining the perigee argument. Calculate the orbital radius based on the aforementioned anomalous point angle, orbital eccentricity, and the semi-major axis of the satellite orbit; Multiply the difference between the rate of change of the ascending node longitude and the Earth's rotational angular velocity by the extrapolated time, and add the ascending node longitude at the ephemeris reference time to obtain the rate of change of the ascending node longitude at the desired time. The satellite's position within the orbital plane at the desired time is calculated based on the latitude argument and the orbital in-plane radius. The satellite's velocity at the required time is calculated based on the latitude argument, the orbital radius, and the difference between the rate of change of longitude at the ascending node and the Earth's rotational angular velocity.

5. The PSS coarse synchronization method based on calendar assistance according to claim 1, characterized in that, The component of the satellite velocity in the signal propagation direction is represented as: The Doppler frequency shift caused by the satellite motion is expressed as: ,in, Let $\frac{ ... This refers to the location information of the terminal device. These are the ECEF coordinates of the satellite. Let V be the velocity vector of the satellite in the ECEF coordinate system. The Doppler shift caused by satellite motion For downlink carrier frequency, It is the speed of light.

6. The PSS coarse synchronization method based on calendar assistance according to claim 1, characterized in that, The preset frequency offset range during the PSS signal search process is expressed as follows: ,in, This is the preset frequency offset range during the PSS signal search process. The Doppler shift caused by satellite motion The subcarrier spacing.

7. The PSS coarse synchronization method based on calendar assistance according to claim 1, characterized in that, The detection process for the synchronization signal block based on the preset frequency offset range specifically includes: Based on the preset frequency offset range, a preset frequency offset is added to the three sets of local sequences to obtain multiple sets of local sequences with preset frequency offsets; The received signal sequence is downsampled and filtered; Calculate the sliding correlation values ​​between multiple sets of local sequences with preset frequency offsets and the downsampled and filtered signal sequences; The integer multiple frequency offset and coarse time offset are obtained by using the sliding correlation value decision. The integer multiple frequency offset is the preset frequency offset of the local sequence corresponding to the effective sliding correlation value. The coarse time offset is the data offset of the data index corresponding to the peak value of the effective sliding correlation value converted to the original sampling rate.

8. The PSS coarse synchronization method based on calendar assistance according to claim 7, characterized in that, The preset frequency offset is represented as: ,in, This is the preset frequency offset range during the PSS signal search process. For subcarrier spacing, It is a natural number.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the calendar-assisted PSS coarse synchronization method as described in any one of claims 1-8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the calendar-assisted PSS coarse synchronization method as described in any one of claims 1-8.

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