Frequency offset determination method and apparatus for signal, electronic device, and computer program product

Abstract

The application discloses a frequency offset determination method and device of a signal, electronic equipment and a computer program product. The method comprises the following steps: using a preset detection window to detect the signal power of a physical random access channel signal, wherein the physical random access channel signal is represented according to the Zadoff-Chu sequence; determining the maximum peak power and two secondary peak powers of the physical random access channel signal based on the preset detection window; determining the peak power ratio of the maximum peak power and the maximum secondary peak power; and analyzing the two secondary peak powers and the peak power ratio based on a preset rule to determine the frequency offset information of the physical random access channel signal. The application solves the technical problem that, in a non-terrestrial network (NTN) scene, due to the relatively serious Doppler effect, the frequency offset is relatively large, and the conventional frequency offset estimation method is not applicable.

Description

Technical Field

[0001] This invention relates to the field of communications, and more specifically, to a method, apparatus, electronic device, and computer program product for determining the frequency offset of a signal. Background Technology

[0002] The Physical Random Access Channel (PRACH) is used to complete uplink synchronization between the UE and the base station, and is the first uplink signal transmitted during the random access process. If there is relative motion between the UE and the base station, or due to non-idealities in the UE's devices, the PRACH signal received by the base station may have a frequency offset. If the base station can accurately estimate the PRACH signal frequency offset, it can use this estimate to compensate for the frequency offset of the received signal, thereby eliminating the impact of the frequency offset on the detection performance of the PRACH and subsequent PUSCH signals. Therefore, PRACH frequency offset estimation is of great significance.

[0003] In non-terrestrial network (NTN) scenarios, the relative motion between the UE and the base station is faster. The commonly used PRACHformat0 has a preamble sequence that does not repeat. Although the frequency offset can be estimated using conventional methods of calculating differential phase, it has limitations and is not applicable in many cases.

[0004] The conventional method for estimating frequency offset using differential phase requires two identical data points s(t) and s(t+T) spaced a certain time interval T, where s(t) = s(t+T). Assuming that the phase of the frequency offset Δf changes linearly with time at different moments, the data with frequency offset can be expressed as s(t)·e j2πΔft and s(t+T)·e j2πΔf(t+T) If the time interval T between these two repeated data points will not cause the phase difference due to the frequency offset to be greater than π or less than -π, then the frequency offset can be estimated using the following method:

[0005] First, calculate the conjugate product of two repeated data points at time interval T: prod conj =conj(s(t)·e j2 πΔft )·s(t+T)·e j2πΔf(t+T) =|s(t)| 2 ·e j2πΔfT Then, calculate the phase of the conjugate product, i.e., s(t)·e j2πΔft and s(t+T)·e j2πΔf(t+T) Phase difference: phase prod =atan(prod conj ) = 2πΔfT; Finally, calculate the frequency offset based on the phase difference:

[0006] For PRACH formats where the preamble is repeatedly transmitted, such as B4 and C2, the frequency offset can be estimated using the above method based on multiple repeated preamble sequences. However, format 0 does not have a repeated preamble, but the CP and the last segment of the preamble with the same length as the CP are identical. Therefore, the frequency offset can be estimated using the phase difference between corresponding samples of these two segments.

[0007] However, estimating frequency offset using the phase difference between the CP and the data at the end of the corresponding preamble can only be done in the time domain. The time domain signals of other channels such as PRACH and PUSCH transmitted in the same time domain are superimposed and cannot be distinguished. The frequency offset estimation using such multi-user time domain signals has a large error or is even incorrect.

[0008] Furthermore, if the PRACH signal power is low and the noise power is high, even if the base station receives only one PRACH signal and there is no interference, the frequency offset estimation result may still have a large error due to the influence of noise.

[0009] In addition, the sampling rate of the received signal in the time domain is relatively high, and the number of samples contained in the CP is relatively large. In order to ensure the accuracy of the frequency offset estimation result, it is usually necessary to use as many sample data as possible to calculate the mean of the conjugate product, then calculate the phase and calculate the frequency offset, so the amount of computation is large.

[0010] In the aforementioned non-terrestrial network (NTN) scenarios, the Doppler effect is severe, resulting in a large frequency offset that renders conventional frequency offset estimation methods inapplicable. Currently, no effective solution has been proposed. Summary of the Invention

[0011] This invention provides a method, apparatus, electronic device, and computer program product for determining the frequency offset of a signal, in order to at least solve the technical problem that conventional frequency offset estimation methods are not applicable in non-terrestrial network (NTN) scenarios due to the severe Doppler effect, which leads to a large frequency offset.

[0012] According to one aspect of the present invention, a method for determining the frequency offset of a signal is provided, comprising: detecting the signal power of a physical random access channel (PRAM) signal using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the PRAM signal, and the PRAM signal is represented according to a Zadov-Chu sequence; and determining, based on the preset detection window, the maximum peak power and two sub-peak powers of the PRAM signal, wherein the maximum peak power is the largest signal power determined in Cartesian coordinates based on the preset detection window, and the sub-peak powers are the largest signal power determined in Cartesian coordinates based on the preset detection window. In Cartesian coordinates, the signal power whose time interval between the maximum peak power and the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence; determine the peak power ratio of the maximum peak power and the maximum second-highest peak power, wherein the maximum second-highest peak power is the largest second-highest peak power; analyze the two second-highest peak powers and the peak power ratio based on preset rules to determine the frequency offset information of the physical random access channel signal, wherein the frequency offset information includes at least: frequency offset value and frequency offset direction, and the preset rules are used to at least represent the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two second-highest peak powers and the frequency offset direction.

[0013] Optionally, the frequency offset information of the physical random access channel signal is determined by analyzing the ratio of the two sub-peak powers and the peak power based on preset rules, including at least: determining the frequency offset direction as positive when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is greater than or equal to the root sequence length of the Zadov-Chu sequence. The frequency offset direction is determined to be negative when the first peak power is greater than the second peak power and the sequence length is half of the root sequence length of the Zadov-Chu sequence; or the frequency offset direction is determined to be negative when the cyclic shift step is greater than or equal to half of the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; wherein the cyclic shift step is the smallest positive integer with a remainder of 1 after being divided by the root sequence length, the first peak power is the second peak power whose time is later than the maximum peak power, and the second peak power is the second peak power whose time is earlier than the maximum peak power.

[0014] Optionally, determining the frequency offset information of the physical random access channel signal by analyzing the ratio of the two sub-peak powers and the peak power based on preset rules includes at least: among multiple preset power ratios recorded in a preset power ratio lookup table, querying the first preset power ratio less than or equal to the peak power ratio as the target power ratio in descending order of the preset power ratios; and querying the frequency offset value mapped to the target power ratio among multiple frequency offset values ​​recorded in the preset power ratio lookup table, wherein the preset power ratio lookup table is used to record multiple sets of frequency offset mapping relationships, and each set of frequency offset mapping relationships is used to represent the mapping between the preset power ratio and the frequency offset value.

[0015] Optionally, among the multiple preset power ratios recorded in the preset power ratio lookup table, the method further includes: determining half of the subcarrier spacing of the physical random access channel as the largest frequency offset value; dividing the largest frequency offset value according to a preset frequency offset granularity to obtain multiple preset frequency offset values; and using the preset power ratio lookup table to record the multiple preset frequency offset values ​​divided according to the frequency offset granularity, and the preset power ratio value corresponding to each frequency offset value.

[0016] Optionally, determining the frequency offset information of the physical random access channel signal by analyzing the ratio of the two sub-peak powers and the peak power based on preset rules includes at least: analyzing the peak power ratio using a preset frequency offset mapping model to obtain the frequency offset value, wherein the preset frequency offset mapping model is: |Δf| is the frequency offset value, peak ratio Let a be the peak power ratio. m Let m be the signal power corresponding to each signal data in the Zadov-Chu sequence of the physical random access channel signal, m be the arrangement position of each signal data in the Zadov-Chu sequence, and M be the arrangement position of the last signal data in the Zadov-Chu sequence, which is determined according to the root sequence length of the Zadov-Chu sequence.

[0017] Optionally, determining the maximum peak power and two sub-peak powers of the physical random access channel signal based on the preset detection window includes: when the physical random access channel signal is the Zadov-Chu sequence, analyzing the root sequence length of the Zadov-Chu sequence using a preset sequence analysis model to obtain the cyclic shift interval of the Zadov-Chu sequence, wherein the preset sequence analysis model is: du is the cyclic shift interval, L RALet q be the length of the root sequence and q be the cyclic shift step size, which is the smallest positive integer whose remainder is 1 when divided by the length of the root sequence. In the Cartesian coordinates based on the preset detection window, query the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval.

[0018] Optionally, after querying the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval in the Cartesian coordinates based on the preset detection window, the method further includes: querying the preset peak power and the tap power of the preset peak power in the Cartesian coordinates based on the preset detection window, wherein the preset peak power includes at least the maximum peak power and the second peak power, and the time interval between the tap power and the preset peak power is a preset interval; comparing the magnitude relationship between the tap power and the noise power threshold, wherein the noise power threshold is the product of the preset noise power and the preset noise power threshold; determining the correction power corresponding to the tap power according to the magnitude relationship between the tap power and the noise power threshold, wherein when the tap power is greater than the noise power threshold, the correction power is the difference between the tap power and the preset noise power, and when the tap power is not greater than the noise power threshold, the correction power is zero; and accumulating the correction power onto the preset peak power to obtain the corrected preset peak power.

[0019] According to another aspect of the present invention, a signal frequency offset determination apparatus is also provided, comprising: a detection module, configured to detect the signal power of a physical random access channel signal using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal, and the physical random access channel signal is represented according to a Zadov-Chu sequence; and a first determination module, configured to determine, based on the preset detection window, the maximum peak power and two sub-peak powers of the physical random access channel signal, wherein the maximum peak power is the largest signal power determined in Cartesian coordinates based on the preset detection window, and the sub-peak powers are the largest signal power determined in Cartesian coordinates based on the preset detection window. In Cartesian coordinates, the signal power whose time interval between the maximum peak power and the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence; a second determining module is used to determine the peak power ratio of the maximum peak power and the maximum second peak power, wherein the maximum second peak power is the largest second peak power; a third determining module is used to analyze the two second peak powers and the peak power ratio based on preset rules to determine the frequency offset information of the physical random access channel signal, wherein the frequency offset information includes at least: frequency offset value and frequency offset direction, and the preset rules are used to at least represent the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two second peak powers and the frequency offset direction.

[0020] According to another aspect of the present invention, an electronic device is also provided, including a memory and a processor, wherein the memory stores a computer program and the processor is configured to execute the frequency offset method of the above-mentioned signal through the computer program.

[0021] According to another aspect of the present invention, a computer program product is also provided, including computer instructions that, when executed by a processor, implement the steps of the frequency offset determination method for the above-described signal.

[0022] In this embodiment of the invention, for a physical random access channel signal represented according to the Zadov-Chu sequence, the true peak power of the signal is the maximum value of all peak powers, and it is located at the cyclic shift interval d. u The second-highest power at integer multiples of the frequency offset changes with frequency offset information, and this change follows a certain pattern. Using this pattern, the maximum peak power of the physical random access channel signal and the positional interval ±d from the maximum peak power can be calculated. uThe maximum second-highest peak power is obtained, and then frequency offset information is obtained by looking up tables or polynomial fitting based on the maximum peak power and the maximum second-highest peak power. This achieves the technical effect of frequency offset estimation in non-terrestrial network NTN scenarios, which is simple to implement and has low computational load. It also solves the technical problem that conventional frequency offset estimation methods are not applicable in non-terrestrial network NTN scenarios due to the large frequency offset caused by the severe Doppler effect. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0024] Figure 1 This is a flowchart of a method for determining the frequency offset of a signal according to an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the peak power distribution under frequency offset according to an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the peak power variation curves at three positions under different frequency offsets according to an embodiment of the present invention;

[0027] Figure 4 This is a true peak value and ±d according to an embodiment of the present invention. u A schematic diagram showing the curve of the ratio of the larger second-highest peak power to the frequency offset.

[0028] Figure 5a This is a schematic diagram of the correlation power with a frequency deviation of 100Hz according to an embodiment of the present invention;

[0029] Figure 5b This is a schematic diagram of the correlation power with a frequency deviation of 200Hz according to an embodiment of the present invention;

[0030] Figure 5c This is a schematic diagram of the correlation power with a frequency offset of 300Hz according to an embodiment of the present invention;

[0031] Figure 5d This is a schematic diagram of the correlation power with a frequency deviation of 400Hz according to an embodiment of the present invention;

[0032] Figure 5e This is a schematic diagram of the correlation power with a frequency deviation of 500Hz according to an embodiment of the present invention;

[0033] Figure 5f This is a schematic diagram of the correlation power with a frequency deviation of 600Hz according to an embodiment of the present invention;

[0034] Figure 6 This is a schematic diagram of a signal frequency offset determination device according to an embodiment of the present invention;

[0035] Figure 7 This is a structural block diagram of a computer terminal according to an embodiment of the present invention. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] According to an embodiment of the present invention, a method for determining the frequency offset of a signal is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0039] Figure 1 This is a flowchart of a method for determining the frequency offset of a signal according to an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes the following steps:

[0040] Step S102: Detect the signal power of the physical random access channel signal using a preset detection window. The preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal. The physical random access channel signal is represented according to the Zadov-Chu sequence.

[0041] Step S104: Based on a preset detection window, determine the maximum peak power and two sub-peak powers of the physical random access channel signal. The maximum peak power is the maximum signal power determined in the Cartesian coordinates based on the preset detection window, and the sub-peak powers are the signal powers in the Cartesian coordinates based on the preset detection window whose time interval with the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence.

[0042] Step S106: Determine the peak power ratio of the maximum peak power and the maximum second-highest peak power, wherein the maximum second-highest peak power is the largest second-highest peak power;

[0043] Step S108: Analyze the two sub-peak powers and the peak power ratio based on preset rules to determine the frequency offset information of the physical random access channel signal. The frequency offset information includes at least the frequency offset value and the frequency offset direction. The preset rules are used to represent at least the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two sub-peak powers and the frequency offset direction.

[0044] In this embodiment of the invention, for a physical random access channel signal represented according to the Zadov-Chu sequence, the true peak power of the signal is the maximum value of all peak powers, and it is located at the cyclic shift interval d. u The second-highest power at integer multiples of the frequency offset changes with frequency offset information, and this change follows a certain pattern. Using this pattern, the maximum peak power of the physical random access channel signal and the positional interval ±d from the maximum peak power can be calculated. u The maximum second-highest peak power is obtained, and then frequency offset information is obtained by looking up tables or polynomial fitting based on the maximum peak power and the maximum second-highest peak power. This achieves the technical effect of frequency offset estimation in non-terrestrial network NTN scenarios, which is simple to implement and has low computational load. It also solves the technical problem that conventional frequency offset estimation methods are not applicable in non-terrestrial network NTN scenarios due to the large frequency offset caused by the severe Doppler effect.

[0045] In step S102 above, the physical random access channel signal can be a random access preamble sequence sent on the physical random access channel PRACH, also known as a preamble. This preamble is mainly used to help the base station detect and synchronize transmission requests from users.

[0046] Alternatively, the preamble of PRACH has two main lengths (i.e., root sequence length): L RA =839 and L RA =139, which are applicable to different scenarios and parameter settings.

[0047] Optionally, the PRACH preamble typically uses the Zadoff-Chu sequence (also known as the ZC sequence), which has good autocorrelation and cross-correlation, making it suitable for uplink synchronization. The ZC sequence generates multiple sequences through cyclic shifting, and the specific length and type are informed to the UE (User Equipment) by the base station through the RRC parameter PRACH Configuration Index.

[0048] As an optional implementation, when multiple PRACHs are received simultaneously, the frequency offset information of each PRACH can be estimated by using different Preamble IDs.

[0049] In step S102 above, the preset detection window can represent the relationship between signal power and time of the received physical random access channel signal using Cartesian coordinates, which facilitates the subsequent determination of the maximum peak power and two sub-peak power of the physical random access channel signal in Cartesian coordinates.

[0050] In step S104 above, the maximum peak power can be the maximum signal power queried in the Cartesian coordinates of a preset detection window.

[0051] In step S104 above, the secondary peak power can be the two signal powers retrieved from both sides of the maximum peak power in a Cartesian coordinate system based on a preset detection window, according to a cyclic shift interval.

[0052] In step S104 above, the cyclic shift interval can be expressed as ±d. u , where d u The second-highest peak power in the positive direction of the maximum peak power in the Cartesian coordinate system is denoted as the first peak power; -d u The second peak power is the power in the negative direction of the maximum peak power in the Cartesian coordinate system.

[0053] Optionally, the cyclic shift interval can be determined based on the cyclic shift step size, which is the smallest positive integer whose remainder is 1 after being divided by the root sequence length of the physical random access channel signal. When the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence, the cyclic shift interval is the cyclic shift step size. When the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence, the cyclic shift interval is the difference between half the root sequence length of the Zadov-Chu sequence and the cyclic shift step size, thereby ensuring that the cyclic shift interval is less than half the root sequence length of the Zadov-Chu sequence.

[0054] In step S106 above, the peak power ratio is the largest of the two secondary peak powers determined based on the maximum peak power.

[0055] In step S108 above, the frequency offset information of the physical random access channel signal is represented by the frequency offset value and the frequency offset direction. The preset rules include at least: a first rule for determining the frequency offset value and a second rule for determining the frequency offset direction.

[0056] Optionally, the first rule is used to represent the mapping relationship between the peak power ratio and the frequency offset. The first rule can be a pre-determined preset power ratio lookup table or a preset frequency offset mapping model obtained in advance through polynomial fitting.

[0057] Optionally, the second rule represents the mapping relationship between the magnitude of the two sub-peak powers and the frequency offset direction.

[0058] As an optional embodiment, the frequency offset information of the physical random access channel signal is determined by analyzing the ratio of two sub-peak powers and the peak power based on preset rules. This includes at least the following: determining the frequency offset direction as positive when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power. The cyclic shift step size is the smallest positive integer whose remainder after dividing by the root sequence length is 1, the first peak power is the sub-peak power whose time is later than the maximum peak power, and the second peak power is the sub-peak power whose time is earlier than the maximum peak power.

[0059] In the above embodiments of this application, the first peak power and the second peak power are determined according to the cyclic shift interval, which is determined according to the cyclic shift step size. The relationship between the cyclic shift step size and half the root sequence length of the Zadov-Chu sequence, as well as the relationship between the first peak power and the second peak power, enables the determination of the frequency offset direction.

[0060] As an optional embodiment, the frequency offset information of the physical random access channel signal is determined by analyzing the ratio of two sub-peak powers and the peak power based on preset rules. This further includes: in a Cartesian coordinate system determined based on a preset detection window, if the position corresponding to the maximum sub-peak power is equal to -q of the position corresponding to the maximum peak power (i.e., the position corresponding to the maximum sub-peak power is in the negative direction of the position corresponding to the maximum peak power, and the interval between the positions corresponding to the maximum sub-peak power and the position corresponding to the maximum peak power conforms to a cyclic shift step), then the frequency offset direction is negative; if the position corresponding to the maximum sub-peak power is equal to +q of the position corresponding to the maximum peak power (i.e., the position corresponding to the maximum sub-peak power is in the positive direction of the position corresponding to the maximum peak power, and the interval between the positions corresponding to the maximum sub-peak power and the position corresponding to the maximum peak power conforms to a cyclic shift step), then the frequency offset direction is positive.

[0061] As an optional embodiment, the frequency offset information of the physical random access channel signal is determined by analyzing two sub-peak powers and the peak power ratio based on preset rules. This includes at least: among multiple preset power ratios recorded in a preset power ratio lookup table, the first preset power ratio less than or equal to the peak power ratio is selected as the target power ratio in descending order of preset power ratios; among multiple frequency offset values ​​recorded in the preset power ratio lookup table, the frequency offset value mapped to the target power ratio is selected. The preset power ratio lookup table is used to record multiple sets of frequency offset mapping relationships, and each set of frequency offset mapping relationships is used to represent the mapping between the preset power ratio and the frequency offset value.

[0062] In the above embodiments of this application, the frequency offset value of the physical random access channel signal can be obtained by looking up a preset power ratio lookup table. The preset power ratio lookup table records multiple sets of predetermined frequency offset mapping relationships. Each set of frequency offset mapping relationships is used to represent the mapping between the preset power ratio and the frequency offset value. Then, based on the peak power ratio of the physical random access channel signal, the first preset power ratio less than or equal to the peak power ratio can be looked up in the preset power ratio lookup table in descending order of preset power ratio. This first preset power ratio is then used as the target power ratio, and the frequency offset value mapped to the target power ratio is looked up, thereby determining the frequency offset value.

[0063] As an optional embodiment, the determination of the frequency offset information of the physical random access channel signal based on the analysis of two sub-peak powers and the peak power ratio according to preset rules further includes: among multiple preset power ratios recorded in a preset power ratio lookup table, in descending order of preset power ratios, querying the first preset power ratio less than or equal to the peak power ratio as the first power ratio, and querying the first preset power ratio greater than the peak power ratio as the second power ratio; among multiple frequency offset values ​​recorded in the preset power ratio lookup table, querying the first frequency offset value mapped by the first power ratio, and the second frequency offset value mapped by the second power ratio, wherein the preset power ratio lookup table is used to record multiple sets of frequency offset mapping relationships, and each set of frequency offset mapping relationships is used to represent the mapping between preset power ratios and frequency offset values; and determining the average value of the first frequency offset value and the second frequency offset value as the frequency offset value of the physical random access channel signal.

[0064] In the above embodiments of this application, by querying a preset power ratio lookup table, a first frequency deviation value corresponding to a first preset power ratio less than or equal to the peak power ratio is determined, and a second frequency deviation value corresponding to a first preset power ratio greater than the peak power ratio is determined, and the frequency deviation value is determined based on the average of the first frequency deviation value and the second frequency deviation value.

[0065] As an optional embodiment, among the multiple preset power ratios recorded in the preset power ratio lookup table, before the first preset power ratio less than or equal to the peak power ratio is selected as the target power ratio, the method further includes: determining half of the subcarrier spacing of the physical random access channel as the maximum frequency offset value; dividing the maximum frequency offset value according to a preset frequency offset granularity to obtain multiple preset frequency offset values; and using the preset power ratio lookup table to record the multiple preset frequency offset values ​​divided according to the frequency offset granularity, and the preset power ratio corresponding to each frequency offset value.

[0066] In the above embodiments of this application, a preset power ratio lookup table records multiple sets of frequency offset mapping relationships that can be recorded in advance. Each set of frequency offset mapping relationships is used to represent the mapping between the preset power ratio and the frequency offset value. The range of frequency offset values ​​recorded in the preset power ratio lookup table can be determined based on half of the subcarrier spacing of the physical random access channel signal. That is, the maximum frequency offset value is half of the subcarrier spacing of the physical random access channel signal. By dividing the maximum frequency offset value according to the preset frequency offset granularity, multiple frequency offset values ​​can be obtained. A corresponding preset power ratio is added to each frequency offset value to obtain multiple sets of frequency offset mapping relationships, thereby realizing the determination of the preset power ratio lookup table records.

[0067] Optionally, the subcarrier spacing of the physical random access channel signal can be 1.25 kHz.

[0068] Optionally, the frequency offset granularity can be 10Hz.

[0069] As an optional embodiment, determining the frequency offset information of the physical random access channel signal by analyzing the two sub-peak powers and the peak power ratio based on preset rules includes at least: analyzing the peak power ratio using a preset frequency offset mapping model to obtain the frequency offset value, wherein the preset frequency offset mapping model is: |Δf| is the frequency offset value, peak ratio a is the peak power ratio. m Let m be the signal power corresponding to each signal data in the Zadov-Chu sequence of the physical random access channel signal, m be the arrangement position of each signal data in the Zadov-Chu sequence, and M be the arrangement position of the last signal data in the Zadov-Chu sequence, which is determined according to the root sequence length of the Zadov-Chu sequence.

[0070] In the above embodiments of this application, the preset frequency offset mapping model is obtained in advance through polynomial fitting and is used to represent the mapping relationship between the peak power ratio and the frequency offset value. After determining the peak power ratio, the frequency offset value corresponding to the peak power ratio can be obtained by analysis based on the preset frequency offset mapping model, thereby realizing the determination of the frequency offset value.

[0071] As an optional embodiment, determining the maximum peak power and two sub-peak powers of the physical random access channel signal based on a preset detection window includes: when the physical random access channel signal is a Zadov-Chu sequence, analyzing the root sequence length of the Zadov-Chu sequence using a preset sequence analysis model to obtain the cyclic shift interval of the Zadov-Chu sequence, wherein the preset sequence analysis model is: du is the cyclic shift interval, L RA q is the root sequence length, and q is the cyclic shift step size, which is the smallest positive integer whose remainder is 1 when divided by the root sequence length. In the Cartesian coordinates based on the preset detection window, query the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval.

[0072] In the above embodiments of this application, the cyclic shift interval can be determined based on the cyclic shift step size, which is the smallest positive integer whose remainder is 1 after being divided by the root sequence length of the physical random access channel signal. When the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence, the cyclic shift interval is the cyclic shift step size; when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence, the cyclic shift interval is the difference between half the root sequence length of the Zadov-Chu sequence and the cyclic shift step size, thereby ensuring that the cyclic shift interval is less than half the root sequence length of the Zadov-Chu sequence.

[0073] As an optional embodiment, after querying the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval in the Cartesian coordinates based on the preset detection window, the method further includes: querying the preset peak power and the tap power of the preset peak power in the Cartesian coordinates based on the preset detection window, wherein the preset peak power includes at least the maximum peak power and the second peak power, and the time interval between the tap power and the preset peak power is a preset interval; comparing the magnitude relationship between the tap power and the noise power threshold, wherein the noise power threshold is the product of the preset noise power and the preset noise power threshold; determining the correction power corresponding to the tap power according to the magnitude relationship between the tap power and the noise power threshold, wherein when the tap power is greater than the noise power threshold, the correction power is the difference between the tap power and the preset noise power, and when the tap power is not greater than the noise power threshold, the correction power is zero; and accumulating the correction power to the preset peak power to obtain the corrected preset peak power.

[0074] In the above embodiments of this application, when the maximum peak power and the second-highest peak power are determined, the larger tap power adjacent to the preset peak power can be added to the preset peak power, which can eliminate the power diffusion effect caused by time delay.

[0075] The present invention also provides a preferred embodiment, which provides a frequency offset estimation method applicable to NTN scenarios. This method can perform frequency offset estimation in non-terrestrial network NTN scenarios, where the Doppler effect is severe and causes a large frequency offset.

[0076] In satellite communication scenarios (i.e., non-terrestrial network NTN scenarios), the Doppler effect is significant, resulting in substantial frequency shifts. The preamble of the Physical Random Access Channel (PRACH) is a Zadoff-Chu sequence, and frequency shifts cause the correlated peak power of the ZC sequence to vary with the cyclic shift interval d of the ZC sequence. u The power is dispersed at intervals that are multiples of the maximum peak value. The further away from the maximum peak value, the smaller the power of the dispersion.

[0077] Optionally, the cyclic shift interval d of the ZC sequence u It can be calculated from the root sequence physical index (i.e., the root index) u of the ZC sequence, as follows:

[0078] Find the satisfaction (q) u )modL RA Find the smallest positive integer q that equals 1, and then calculate the cyclic shift interval d of the ZC sequence according to the following formula. u :

[0079]

[0080] Where u is the root index, L RA Let L be the root sequence length of the ZC sequence. For format0, L RA =839, where q is a specific cyclic shift step size. If the value of q is between 0 and L... RA If the value is between 2 and 1, then q is used directly as the cyclic shift interval d. u If the value of q is greater than or equal to L RA Then use L RA -q is used as the cyclic shift interval d u .

[0081] Figure 2 This is a schematic diagram of the peak power distribution under frequency offset according to an embodiment of the present invention, as shown below. Figure 2 The figure shows the correlated power at a frequency deviation of 375Hz, where u = 95 and d u =53. We can see that besides the maximum peak at position 1, two larger secondary peaks also appear simultaneously at positions 54 and 787. If the frequency offset is 0, there will only be one maximum peak at position 1, and no secondary peaks will appear at other positions. Therefore, position 1 is taken as the true peak position. The interval between the positions of the two secondary peaks and the true peak position is equal to d. u , that is, 54=1+du, 787=mod(1-du-1,L RA )+1.

[0082] It should be noted that when the absolute value of the frequency offset Δf is less than the subcarrier spacing Δf RA In the case of 1 / 2, the true peak position remains unchanged, and the power of the true peak is the maximum value of all peak powers. Therefore, the power of this true peak is the maximum peak power, and the power of the other peaks is the next highest peak power. And the power located at integer multiples of d... u The subpeak power at a given frequency will change with frequency offset, and the change in subpeak power follows a certain pattern.

[0083] Figure 3 This is a schematic diagram of the peak power variation curves at three positions under different frequency offsets according to an embodiment of the present invention, as shown below. Figure 3 As shown, the true peak (i.e., the maximum peak) is located at 0 and ±d. u The curve showing the variation of the second-peak power with frequency offset at a certain point, from Figure 3 As can be seen from this, when the frequency offset is positive, d u The second peak value at that point must be greater than -d. u The second peak value at the point; when the frequency offset is negative, d u The second peak value at that point should be less than -d. uThe second-highest value at point d. This pattern can be used to determine the sign of the frequency offset, and the magnitude of the frequency offset can be roughly estimated based on the ratio of the peak power of the larger second-highest value to the peak power of the true peak value. For example, when the normalized frequency offset is 0.5, at point d... u The ratio of the peak power at the current location to the peak power at the actual location is 1.

[0084] Figure 4 This is a true peak value and ±d according to an embodiment of the present invention. u A schematic diagram showing the ratio of the larger second-highest peak power to the frequency offset, as shown in the figure. Figure 4 As shown, the true peak power (i.e., the maximum peak power) and ±d u The curve showing the ratio of the larger subpeak power to the frequency offset, where the normalized frequency offset on the horizontal axis is equal to the frequency offset Δf divided by the subcarrier spacing Δf. RA .

[0085] As an optional example, determining the frequency offset includes the following steps:

[0086] Step S201: Search for the maximum correlation peak and determine the location and distance ±d of the maximum peak. u The positions of the two secondary peaks.

[0087] Optionally, the position of the maximum peak is denoted as index0, and the distance from the position of the maximum peak is ±d. u The positions of the two secondary peaks are as follows:

[0088] Step S202: Calculate the peak power of the maximum peak and the two sub-peaks.

[0089] Figure 5a This is a schematic diagram of the correlation power with a frequency deviation of 100Hz according to an embodiment of the present invention. Figure 5b This is a schematic diagram of the correlation power with a frequency offset of 200Hz according to an embodiment of the present invention. Figure 5c This is a schematic diagram of the correlation power with a frequency offset of 300Hz according to an embodiment of the present invention. Figure 5d This is a schematic diagram of the correlation power with a frequency offset of 400Hz according to an embodiment of the present invention. Figure 5e This is a schematic diagram of the correlation power with a frequency deviation of 500Hz according to an embodiment of the present invention. Figure 5f This is a schematic diagram of the correlated power with a frequency offset of 600Hz according to an embodiment of the present invention, as shown below. Figures 5a to 5f As shown, the relevant power includes: the maximum peak power and the second-highest peak power, where the maximum peak power is the peak power at the actual location, denoted as P. real The second peak power is divided into: d u Peak power at -du The peak power at each point is denoted as P. du and P -du Time delay causes power dispersion, dispersing the peak power (i.e., the maximum peak power) and the second-highest peak power at the actual location to the left and right adjacent taps, as follows: Figures 5a to 5f As shown, the frequency deviations are 100Hz to 600Hz (d u =15) related power graph. Therefore, to ensure P real P du and P -du The accuracy of these three peak power calculations requires the useful power diffused from the adjacent taps to the left and right to be added to the peak power. Simultaneously, to prevent noise power from being added, a noise power threshold (TH) can be set. noise Only greater than P noise ·TH noise The power of adjacent taps will be added to the peak power, and the noise power can be subtracted by half before accumulation. noise This represents noise power.

[0090] Optionally, the adjacent tap positions to the left and right of the peak can be selected as left 1 and right 2, with d u The second peak power P at the location du For example, the calculation formula is:

[0091] P du =P du-1 +P du +P du+1 +P du+2 ;

[0092] in,

[0093] Step S203: Calculate the ratio of the maximum peak power to the larger second-highest peak power, i.e., the peak power ratio. ratio =P real / max(P du ,P -du ), where peak ratio P is the peak power ratio. real For the maximum peak power, P du For d u The second peak power at P -du -d u The second-peak power at that location.

[0094] Step S204: Obtain an estimate of the absolute value of the frequency offset.

[0095] Optionally, the ratio of the maximum peak power to the next largest peak power is peak. ratioThe absolute value of the frequency offset can be obtained by methods such as table lookup or polynomial fitting.

[0096] Table 1 shows a comparison table of frequency deviation and peak power ratios. Figure 4 The frequency offset and peak power ratio corresponding to each point in the curve are stored in a two-dimensional table. To ensure the accuracy of frequency offset estimation, the granularity of the pre-stored frequency offset in the table can be set to a smaller value. As shown in Table 1, the frequency offset granularity is 10Hz, and each frequency offset corresponds to a peak power ratio. ratio The PRACHformat0 subcarrier spacing is 1250Hz, and the maximum normalized frequency offset of 0.5 corresponds to a maximum frequency offset of 625Hz. Therefore, there are a total of 124 values ​​in the table.

[0097] Table 1

[0098]

[0099]

[0100]

[0101] As an optional implementation, the calculated peak power ratio (peak_ratio) is compared sequentially with the peak power ratios in the table, starting from the first one, to find the values ​​in the table that are less than the peak power ratio (peak_ratio). ratio The index of the first pre-stored peak power ratio is used to output the absolute value of frequency offset |Δf|.

[0102] Optionally, the data stored in the table can be represented as a matrix table with dimensions N*2, where N is the number of frequency offset values. Then, |Δf| is calculated using the following formula:

[0103]

[0104] As an optional embodiment, Figure 4 The curve shown can be fitted to a polynomial, namely:

[0105] Optionally, the calculated peak power ratio peak_ratio can be substituted into the polynomial above to obtain the absolute value of frequency offset |Δf|.

[0106] Optionally, the sign of the frequency offset direction needs to be determined by comparing ±d. u The magnitudes of the two secondary peak powers at point q are used to determine this, specifically as follows: when 0 ≤ q <L RA When / 2, if P du >P -du If the frequency deviation is positive, then the direction is positive; otherwise, it is negative. RA / 2≤q <LRA When, if P du >P -du If the frequency deviation is positive, then the direction of the frequency deviation is negative; otherwise, it is positive.

[0107] According to an embodiment of the present invention, a signal frequency offset determination device embodiment is also provided. It should be noted that the signal frequency offset determination device can be used to execute the signal frequency offset determination method in the embodiments of the present invention, and the signal frequency offset determination method in the embodiments of the present invention can be executed in the signal frequency offset determination device.

[0108] Figure 6 This is a schematic diagram of a signal frequency offset determination device according to an embodiment of the present invention, as shown below. Figure 6 As shown, the device may include: a detection module 62, used to detect the signal power of the physical random access channel signal using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal, and the physical random access channel signal is represented according to the Zadov-Chu sequence; and a first determination module 64, used to determine the maximum peak power and two sub-peak powers of the physical random access channel signal based on the preset detection window, wherein the maximum peak power is the maximum signal power determined in the Cartesian coordinates based on the preset detection window, and the sub-peak powers are the maximum signal power determined in the Cartesian coordinates based on the preset detection window. The signal power whose time interval between the maximum peak power and the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence; the second determining module 66 is used to determine the peak power ratio of the maximum peak power and the maximum second peak power, wherein the maximum second peak power is the largest second peak power; the third determining module 68 is used to analyze the two second peak powers and the peak power ratio based on preset rules to determine the frequency offset information of the physical random access channel signal, wherein the frequency offset information includes at least: frequency offset value and frequency offset direction, and the preset rules are used to represent at least the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two second peak powers and the frequency offset direction.

[0109] It should be noted that the detection module 62 in this embodiment can be used to execute step S102 in this application embodiment, the first determining module 64 in this embodiment can be used to execute step S104 in this application embodiment, the second determining module 66 in this embodiment can be used to execute step S106 in this application embodiment, and the third determining module 68 in this embodiment can be used to execute step S108 in this application embodiment. The examples and application scenarios implemented by the above modules and corresponding steps are the same, but are not limited to the content disclosed in the above embodiments.

[0110] In this embodiment of the invention, for a physical random access channel signal represented according to the Zadov-Chu sequence, the true peak power of the signal is the maximum value of all peak powers, and it is located at the cyclic shift interval d.u The second-highest power at integer multiples of the frequency offset changes with frequency offset information, and this change follows a certain pattern. Using this pattern, the maximum peak power of the physical random access channel signal, and the positional interval ±d between the maximum peak power and the second-highest power, can be calculated. u The maximum second-highest peak power is obtained, and then frequency offset information is obtained by looking up tables or polynomial fitting based on the maximum peak power and the maximum second-highest peak power. This achieves the technical effect of frequency offset estimation in non-terrestrial network NTN scenarios, which is simple to implement and has low computational load. It also solves the technical problem that conventional frequency offset estimation methods are not applicable in non-terrestrial network NTN scenarios due to the large frequency offset caused by the severe Doppler effect.

[0111] As an optional embodiment, the third determining module includes at least: a first determining unit, configured to determine the frequency offset direction as positive when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or a second determining unit, configured to determine the frequency offset direction as negative when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; or a third determining unit, configured to determine the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or a fourth determining unit, configured to determine the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; wherein the cyclic shift step size is the smallest positive integer with a remainder of 1 after being divided by the root sequence length, the first peak power is the second peak power whose time is later than the maximum peak power, and the second peak power is the second peak power whose time is earlier than the maximum peak power.

[0112] As an optional embodiment, the third determining module includes at least: a first query unit, configured to query, in descending order of preset power ratios recorded in a preset power ratio lookup table, the first preset power ratio less than or equal to the peak power ratio as the target power ratio; and a second query unit, configured to query, in descending order of frequency offsets recorded in the preset power ratio lookup table, the frequency offset value mapped to the target power ratio. The preset power ratio lookup table records multiple sets of frequency offset mapping relationships, each set representing the mapping between the preset power ratio and the frequency offset value.

[0113] As an optional embodiment, the device further includes: a first determining submodule, configured to determine half of the subcarrier spacing of the physical random access channel as the maximum frequency offset value before querying the first preset power ratio less than or equal to the peak power ratio as the target power ratio from among multiple preset power ratios recorded in a preset power ratio lookup table in descending order of preset power ratios; a dividing submodule, configured to divide the maximum frequency offset value according to a preset frequency offset granularity to obtain multiple preset frequency offset values; and a recording submodule, configured to record the multiple preset frequency offset values ​​divided according to the frequency offset granularity and the preset power ratio value corresponding to each frequency offset value using the preset power ratio lookup table.

[0114] As an optional embodiment, the third determining module includes at least: a first analysis unit, used to analyze the peak power ratio using a preset frequency offset mapping model to obtain a frequency offset value, wherein the preset frequency offset mapping model is: |Δf| is the frequency offset value, peak ratio a is the peak power ratio. m Let m be the signal power corresponding to each signal data in the Zadov-Chu sequence of the physical random access channel signal, m be the arrangement position of each signal data in the Zadov-Chu sequence, and M be the arrangement position of the last signal data in the Zadov-Chu sequence, which is determined according to the root sequence length of the Zadov-Chu sequence.

[0115] As an optional embodiment, the first determining module includes: a second analysis unit, configured to analyze the root sequence length of the Zadov-Chu sequence using a preset sequence analysis model when the physical random access channel signal is a Zadov-Chu sequence, and obtain the cyclic shift interval of the Zadov-Chu sequence, wherein the preset sequence analysis model is: du is the cyclic shift interval, L RA q is the root sequence length, and q is the cyclic shift step size, which is the smallest positive integer whose remainder is 1 after being divided by the root sequence length; the third query unit is used to query the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval in the Cartesian coordinates based on the preset detection window.

[0116] As an optional embodiment, the device further includes: a query submodule, configured to query the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval in a Cartesian coordinate plane based on a preset detection window, and then query a preset peak power and a tap power of the preset peak power in a Cartesian coordinate plane based on the preset detection window, wherein the preset peak power includes at least the maximum peak power and the second peak power, and the time interval between the tap power and the preset peak power is a preset interval; a comparison submodule, configured to compare the magnitude relationship between the tap power and a noise power threshold, wherein the noise power threshold is the product of a preset noise power and a preset noise power threshold; a second determination submodule, configured to determine the correction power corresponding to the tap power based on the magnitude relationship between the tap power and the noise power threshold, wherein when the tap power is greater than the noise power threshold, the correction power is the difference between the tap power and the preset noise power, and when the tap power is not greater than the noise power threshold, the correction power is zero; and an accumulation submodule, configured to accumulate the correction power onto the preset peak power to obtain the corrected preset peak power.

[0117] Embodiments of the present invention can provide an electronic device, which can be a computer terminal, and the computer terminal can be any one of a group of computer terminal devices. Optionally, in this embodiment, the computer terminal can also be replaced by a mobile terminal or other terminal device.

[0118] Optionally, in this embodiment, the computer terminal may be located in at least one of a plurality of network devices in a computer network.

[0119] In this embodiment, the computer terminal described above can execute the program code for the following steps in the signal frequency offset determination method: detecting the signal power of the physical random access channel signal using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal, and the physical random access channel signal is represented according to the Zadov-Chu sequence; based on the preset detection window, determining the maximum peak power and two sub-peak powers of the physical random access channel signal, wherein the maximum peak power is the maximum signal power determined in Cartesian coordinates based on the preset detection window, and the sub-peak powers are the maximum signal power determined in Cartesian coordinates based on the preset detection window. In the Cartesian coordinates of the preset detection window, the signal power whose time interval between the maximum peak power and the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence is determined; the peak power ratio of the maximum peak power and the maximum second-highest peak power is determined, wherein the maximum second-highest peak power is the largest second-highest peak power; based on preset rules, the two second-highest peak powers and the peak power ratio are analyzed to determine the frequency offset information of the physical random access channel signal, wherein the frequency offset information includes at least: frequency offset value and frequency offset direction, and the preset rules are used to represent at least the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two second-highest peak powers and the frequency offset direction.

[0120] Figure 7 This is a structural block diagram of a computer terminal according to an embodiment of the present invention, such as... Figure 7 As shown, the computer terminal 70 may include one or more (only one is shown in the figure) processors 72 and memory 74.

[0121] The memory can be used to store software programs and modules, such as the program instructions / modules corresponding to the signal frequency offset determination method and apparatus in this embodiment of the invention. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory, thereby realizing the aforementioned signal frequency offset determination method. The memory may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory may further include memory remotely located relative to the processor, and these remote memories can be connected to the terminal 70 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0122] The processor can invoke information and application programs stored in the memory via a transmission device to perform the following steps: Detecting the signal power of the physical random access channel signal using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal, and the physical random access channel signal is represented according to the Zadov-Chu sequence; Based on the preset detection window, determining the maximum peak power and two sub-peak powers of the physical random access channel signal, wherein the maximum peak power is the maximum signal power determined in Cartesian coordinates based on the preset detection window, and the sub-peak powers are the signal powers whose time interval with the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence in Cartesian coordinates based on the preset detection window; Determining the peak power ratio of the maximum peak power and the maximum sub-peak power, wherein the maximum sub-peak power is the largest sub-peak power; Analyzing the two sub-peak powers and the peak power ratio based on preset rules to determine the frequency offset information of the physical random access channel signal, wherein the frequency offset information includes at least: a frequency offset value and a frequency offset direction, and the preset rules are used to represent at least the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two sub-peak powers and the frequency offset direction.

[0123] Optionally, the processor may also execute program code with the following steps: determining the frequency offset direction as positive when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; wherein the cyclic shift step size is the smallest positive integer with a remainder of 1 after being divided by the root sequence length, the first peak power is the second peak power whose time is later than the maximum peak power, and the second peak power is the second peak power whose time is earlier than the maximum peak power.

[0124] Optionally, the processor may also execute program code that performs the following steps: among multiple preset power ratios recorded in the preset power ratio lookup table, the first preset power ratio less than or equal to the peak power ratio is selected as the target power ratio in descending order of preset power ratios; among multiple frequency offset values ​​recorded in the preset power ratio lookup table, the frequency offset value mapped to the target power ratio is selected, wherein the preset power ratio lookup table is used to record multiple sets of frequency offset mapping relationships, and each set of frequency offset mapping relationships is used to represent the mapping between the preset power ratio and the frequency offset value.

[0125] Optionally, the processor may also execute program code that performs the following steps: determining half of the subcarrier spacing of the physical random access channel as the maximum frequency offset value; dividing the maximum frequency offset value according to a preset frequency offset granularity to obtain multiple preset frequency offset values; and using a preset power ratio lookup table to record the multiple preset frequency offset values ​​divided according to the frequency offset granularity and the preset power ratio corresponding to each frequency offset value.

[0126] Optionally, the processor may also execute program code that performs the following steps: analyzes the peak power ratio using a preset frequency offset mapping model to obtain the frequency offset value, wherein the preset frequency offset mapping model is: |Δf| is the frequency offset value, peak ratio a is the peak power ratio. m Let m be the signal power corresponding to each signal data in the Zadov-Chu sequence of the physical random access channel signal, m be the arrangement position of each signal data in the Zadov-Chu sequence, and M be the arrangement position of the last signal data in the Zadov-Chu sequence, which is determined according to the root sequence length of the Zadov-Chu sequence.

[0127] Optionally, the processor may also execute program code for the following steps: When the physical random access channel signal is a Zadov-Chu sequence, analyze the root sequence length of the Zadov-Chu sequence using a preset sequence analysis model to obtain the cyclic shift interval of the Zadov-Chu sequence, wherein the preset sequence analysis model is: du is the cyclic shift interval, L RA q is the root sequence length, and q is the cyclic shift step size, which is the smallest positive integer whose remainder is 1 when divided by the root sequence length. In the Cartesian coordinates based on the preset detection window, query the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval.

[0128] Optionally, the processor may also execute program code for the following steps: In a Cartesian coordinate system based on a preset detection window, query a preset peak power and a tap power of the preset peak power, wherein the preset peak power includes at least a maximum peak power and a second-highest peak power, and the time interval between the tap power and the preset peak power is a preset interval; compare the magnitude of the tap power with a noise power threshold, wherein the noise power threshold is the product of a preset noise power and a preset noise power threshold; determine the correction power corresponding to the tap power based on the magnitude of the tap power and the noise power threshold, wherein if the tap power is greater than the noise power threshold, the correction power is the difference between the tap power and the preset noise power, and if the tap power is not greater than the noise power threshold, the correction power is zero; accumulate the correction power onto the preset peak power to obtain the corrected preset peak power.

[0129] Those skilled in the art will understand that Figure 7 The structure shown is for illustrative purposes only. The computer terminal can also be a smartphone (such as an Android phone, an iOS phone, etc.), a tablet computer, a mobile internet device (MID), a PAD, and other terminal devices. Figure 7 This does not limit the structure of the aforementioned electronic device. For example, the computer terminal 7 may also include components that are more... Figure 7 The more or fewer components shown (such as network interfaces, display devices, etc.), or having the same Figure 7 The different configurations shown.

[0130] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a computer program instructing the hardware related to the terminal device. The computer program can be stored in a non-volatile medium, which may include: flash drive, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, etc.

[0131] Embodiments of the present invention also provide a non-volatile storage medium. Optionally, in this embodiment, the aforementioned non-volatile storage medium can be used to store the program code executed by the frequency offset determination method for the signal provided in the above embodiments.

[0132] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a group of computer terminals in a computer network, or in any mobile terminal in a group of mobile terminals.

[0133] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: detecting the signal power of the physical random access channel signal using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal, and the physical random access channel signal is represented according to the Zadov-Chu sequence; based on the preset detection window, determining the maximum peak power and two sub-peak powers of the physical random access channel signal, wherein the maximum peak power is the maximum signal power determined in Cartesian coordinates based on the preset detection window, and the sub-peak powers are... Based on the Cartesian coordinates of the preset detection window, the signal power whose time interval between the maximum peak power and the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence is determined; the peak power ratio of the maximum peak power and the maximum second-highest peak power is determined, wherein the maximum second-highest peak power is the largest second-highest peak power; based on the preset rules, the two second-highest peak powers and the peak power ratio are analyzed to determine the frequency offset information of the physical random access channel signal, wherein the frequency offset information includes at least: frequency offset value and frequency offset direction, and the preset rules are used to represent at least the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two second-highest peak powers and the frequency offset direction.

[0134] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: determining the frequency offset direction as positive when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is greater than the second peak power; or determining the frequency offset direction as negative when the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence and the first peak power is less than the second peak power; wherein the cyclic shift step size is the smallest positive integer with a remainder of 1 after being divided by the root sequence length, the first peak power is the second peak power that is later than the maximum peak power, and the second peak power is the second peak power that is earlier than the maximum peak power.

[0135] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: among a plurality of preset power ratios recorded in a preset power ratio lookup table, the first preset power ratio less than or equal to the peak power ratio is selected as the target power ratio in descending order of the preset power ratios; among a plurality of frequency offset values ​​recorded in the preset power ratio lookup table, the frequency offset value mapped to the target power ratio is selected, wherein the preset power ratio lookup table is used to record multiple sets of frequency offset mapping relationships, and each set of frequency offset mapping relationships is used to represent the mapping between the preset power ratio and the frequency offset value.

[0136] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: determining half of the subcarrier spacing of the physical random access channel as the maximum frequency offset value; dividing the maximum frequency offset value according to a preset frequency offset granularity to obtain multiple preset frequency offset values; and using a preset power ratio lookup table to record the multiple preset frequency offset values ​​divided according to the frequency offset granularity and the preset power ratio corresponding to each frequency offset value.

[0137] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: analyzing the peak power ratio using a preset frequency offset mapping model to obtain the frequency offset value, wherein the preset frequency offset mapping model is: |Δf| is the frequency offset value, peak ratio a is the peak power ratio. m Let m be the signal power corresponding to each signal data in the Zadov-Chu sequence of the physical random access channel signal, m be the arrangement position of each signal data in the Zadov-Chu sequence, and M be the arrangement position of the last signal data in the Zadov-Chu sequence, which is determined according to the root sequence length of the Zadov-Chu sequence.

[0138] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: when the physical random access channel signal is a Zadov-Chu sequence, the root sequence length of the Zadov-Chu sequence is analyzed using a preset sequence analysis model to obtain the cyclic shift interval of the Zadov-Chu sequence, wherein the preset sequence analysis model is: du is the cyclic shift interval, L RA q is the root sequence length, and q is the cyclic shift step size, which is the smallest positive integer whose remainder is 1 when divided by the root sequence length. In the Cartesian coordinates based on the preset detection window, query the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval.

[0139] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: querying a preset peak power and a tap power of the preset peak power in a Cartesian coordinate system based on a preset detection window, wherein the preset peak power includes at least a maximum peak power and a second-highest peak power, and the time interval between the tap power and the preset peak power is a preset interval; comparing the magnitude of the tap power with a noise power threshold, wherein the noise power threshold is the product of a preset noise power and a preset noise power threshold; determining a correction power corresponding to the tap power based on the magnitude of the tap power and the noise power threshold, wherein when the tap power is greater than the noise power threshold, the correction power is the difference between the tap power and the preset noise power, and when the tap power is not greater than the noise power threshold, the correction power is zero; and accumulating the correction power onto the preset peak power to obtain the corrected preset peak power.

[0140] Embodiments of the present invention also provide a computer program product, including a computer program. Optionally, in this embodiment, when the computer program is executed by a processor, it implements the steps of the signal frequency offset determination method provided in the above embodiments.

[0141] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0142] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0143] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0144] 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 units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0145] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0146] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a non-volatile storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a non-volatile 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 the present invention. The aforementioned non-volatile storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0147] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for determining the frequency offset of a signal, characterized in that, include: The signal power of the physical random access channel signal is detected using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal, and the physical random access channel signal is represented according to the Zadov-Chu sequence; Based on the preset detection window, the maximum peak power and two sub-peak powers of the physical random access channel signal are determined, wherein the maximum peak power is the largest signal power determined in the Cartesian coordinates based on the preset detection window, and the sub-peak powers are the signal powers in the Cartesian coordinates based on the preset detection window whose time interval with the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence. Determine the peak power ratio of the maximum peak power and the maximum second-highest peak power, wherein the maximum second-highest peak power is the largest of the second-highest peak power; Based on preset rules, the frequency offset information of the physical random access channel signal is determined by analyzing the ratio of the two sub-peak powers and the peak power. Specifically, a preset frequency offset mapping model is used to analyze the peak power ratio to obtain the frequency offset value. The preset frequency offset mapping model is as follows: , The frequency offset value is... The peak power ratio is... Let m be the signal power corresponding to each signal data in the Zadov-Chu sequence of the physical random access channel signal, m be the arrangement position of each signal data in the Zadov-Chu sequence, and M be the arrangement position of the last signal data in the Zadov-Chu sequence, determined according to the root sequence length of the Zadov-Chu sequence; the frequency offset information includes at least: frequency offset value and frequency offset direction, and the preset rule is used to at least represent the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two secondary peak powers and the frequency offset direction.

2. The method according to claim 1, characterized in that, Based on preset rules, the frequency offset information of the physical random access channel signal is determined by analyzing the ratio of the two sub-peak powers and the peak power, including at least: If the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence, and the first peak power is greater than the second peak power, the frequency offset direction is determined to be positive; or If the cyclic shift step size is less than half the root sequence length of the Zadov-Chu sequence, and the first peak power is less than the second peak power, the frequency offset direction is determined to be negative; or If the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence, and the first peak power is greater than the second peak power, the frequency offset direction is determined to be negative; or If the cyclic shift step size is greater than or equal to half the root sequence length of the Zadov-Chu sequence, and the first peak power is less than the second peak power, the frequency offset direction is determined to be negative. Wherein, the cyclic shift step size is the smallest positive integer with a remainder of 1 after being divided by the root sequence length, the first peak power is the second peak power whose time is later than the maximum peak power, and the second peak power is the second peak power whose time is earlier than the maximum peak power.

3. The method according to claim 1, characterized in that, Based on preset rules, the frequency offset information of the physical random access channel signal is determined by analyzing the ratio of the two sub-peak powers and the peak power, including at least: Among the multiple preset power ratios recorded in the preset power ratio lookup table, the first preset power ratio less than or equal to the peak power ratio is selected as the target power ratio, following the order of the preset power ratios from largest to smallest. Among the multiple frequency offset values ​​recorded in the preset power ratio lookup table, the frequency offset value mapped to the target power ratio is queried. The preset power ratio lookup table is used to record multiple sets of frequency offset mapping relationships, and each set of frequency offset mapping relationships is used to represent the mapping between the preset power ratio and the frequency offset value.

4. The method according to claim 3, characterized in that, Among the multiple preset power ratios recorded in the preset power ratio lookup table, the method further includes, in descending order of the preset power ratios, searching for the first preset power ratio less than or equal to the peak power ratio before the target power ratio, the method also includes: The maximum frequency offset value is determined by half of the subcarrier spacing of the physical random access channel; The largest frequency offset value is divided according to a preset frequency offset granularity to obtain multiple preset frequency offset values; The preset power ratio lookup table is used to record multiple preset frequency deviation values ​​divided according to the frequency deviation granularity, and the preset power ratio value corresponding to each frequency deviation value.

5. The method according to claim 1, characterized in that, Based on the preset detection window, determining the maximum peak power and two sub-peak powers of the physical random access channel signal includes: When the physical random access channel signal is the Zadov-Chu sequence, the root sequence length of the Zadov-Chu sequence is analyzed using a preset sequence analysis model to obtain the cyclic shift interval of the Zadov-Chu sequence. The preset sequence analysis model is as follows: , The cyclic shift interval is... Let q be the length of the root sequence, and q be the cyclic shift step size, which is the smallest positive integer whose remainder when divided by the length of the root sequence is 1. In the Cartesian coordinates based on the preset detection window, query the maximum peak power and the second peak power whose time interval with the maximum peak power conforms to the cyclic shift interval.

6. The method according to claim 1, characterized in that, After querying the maximum peak power and the second-highest peak power whose time interval with the maximum peak power conforms to the cyclic shift interval in the Cartesian coordinates based on the preset detection window, the method further includes: In the Cartesian coordinates of the plane based on the preset detection window, query the preset peak power and the tap power of the preset peak power, wherein the preset peak power includes at least the maximum peak power and the second-highest peak power, and the time interval between the tap power and the preset peak power is a preset interval; Compare the relationship between the tap power and the noise power threshold, wherein the noise power threshold is the product of a preset noise power and a preset noise power threshold. Based on the relationship between the tap power and the noise power threshold, a correction power corresponding to the tap power is determined. Wherein, when the tap power is greater than the noise power threshold, the correction power is the difference between the tap power and the preset noise power; when the tap power is not greater than the noise power threshold, the correction power is zero. The corrected power is added to the preset peak power to obtain the corrected preset peak power.

7. A device for determining the frequency offset of a signal, characterized in that, include: The detection module is used to detect the signal power of the physical random access channel signal using a preset detection window, wherein the preset detection window uses Cartesian coordinates to represent the relationship between the signal power and time of the physical random access channel signal, and the physical random access channel signal is represented according to the Zadov-Chu sequence; The first determining module is used to determine the maximum peak power and two sub-peak powers of the physical random access channel signal based on the preset detection window, wherein the maximum peak power is the largest signal power determined in the Cartesian coordinates based on the preset detection window, and the sub-peak powers are the signal powers in the Cartesian coordinates based on the preset detection window whose time interval with the maximum peak power conforms to the cyclic shift interval of the Zadov-Chu sequence. The second determining module is used to determine the peak power ratio of the maximum peak power and the maximum second peak power, wherein the maximum second peak power is the largest of the second peak power; The third determining module is used to analyze the ratio of the two sub-peak powers and the peak power based on preset rules to determine the frequency offset information of the physical random access channel signal. Specifically, a preset frequency offset mapping model is used to analyze the peak power ratio to obtain the frequency offset value. The preset frequency offset mapping model is as follows: , The frequency offset value is... The peak power ratio is... Let m be the signal power corresponding to each signal data in the Zadov-Chu sequence of the physical random access channel signal, m be the arrangement position of each signal data in the Zadov-Chu sequence, and M be the arrangement position of the last signal data in the Zadov-Chu sequence, determined according to the root sequence length of the Zadov-Chu sequence; the frequency offset information includes at least: frequency offset value and frequency offset direction, and the preset rule is used to at least represent the mapping relationship between the peak power ratio and the frequency offset value, and the mapping relationship between the magnitude of the two secondary peak powers and the frequency offset direction.

8. An electronic device comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is configured to execute the frequency offset determination method for the signal according to any one of claims 1 to 6 through the computer program.

9. A computer program product comprising computer instructions, characterized in that, When the computer instructions are executed by the processor, they implement the steps of the frequency offset determination method for the signal according to any one of claims 1 to 6.

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