Signal frequency offset estimation method, device, apparatus and storage medium

Abstract

Embodiments of the present application provide a signal frequency offset estimation method, device, apparatus and storage medium, the signal frequency offset estimation method comprising: receiving one or more physical random access channel (PRACH) signals sent by a terminal; determining a maximum peak power of a target PRACH signal based on a preamble ID of the target PRACH signal in the one or more PRACH signals; and determining a first frequency offset estimation value of the target PRACH signal based on the maximum peak power of the target PRACH signal. Embodiments of the present application can avoid the defect that the frequency offset of the PRACH signal cannot be accurately estimated using the differential phase method due to the overlap between the multiple PRACH received signals, and effectively improve the accuracy of the frequency offset estimation of the received one or more PRACH signals.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a signal frequency offset estimation method, device, apparatus and storage medium. Background Technology

[0002] The Physical Random Access Channel (PRACH) is used for uplink synchronization between the User Equipment (UE) and network-side equipment. The PRACH signal is the first uplink signal transmitted during the random access process. If there is relative motion between the UE and the network-side equipment, or if the UE is a non-ideal device, the PRACH signal received by the network-side equipment may have a frequency offset. If the network-side equipment can accurately estimate the frequency offset of the PRACH signal, 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 Physical Uplink Shared Channel (PUSCH) signals. Therefore, frequency offset estimation of the PRACH signal is of great significance.

[0003] In existing technologies, the differential phase method is commonly used to estimate the frequency offset of received PRACH signals. However, for PRACH signals with non-repeating pilot (preamble) sequences, the frequency offset estimation method based on differential phase calculation is not applicable in many scenarios. Summary of the Invention

[0004] This application provides a signal frequency offset estimation method, device, apparatus, and storage medium in the field of communication technology to solve the problem that the existing PRACH signal frequency offset estimation method is not applicable in many scenarios, and realizes the estimation of the PRACH signal frequency offset.

[0005] In a first aspect, embodiments of this application provide a signal frequency offset estimation method, the method comprising:

[0006] Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0007] Based on the preambleID of the target PRACH signal among the one or more PRACH signals, the maximum peak power of the target PRACH signal is determined;

[0008] Based on the maximum peak power of the target PRACH signal, a first frequency offset estimate of the target PRACH signal is determined;

[0009] The maximum peak power is used to represent the received power of the PRACH signal.

[0010] Optionally, according to a signal frequency offset estimation method of one embodiment of this application, determining a first frequency offset estimate of the target PRACH signal based on the maximum peak power of the target PRACH signal includes:

[0011] Determine the absolute value of the first frequency offset estimate;

[0012] Determine the sign of the first frequency offset estimate.

[0013] Optionally, according to a signal frequency offset estimation method of one embodiment of this application, determining the absolute value of the first frequency offset estimate includes:

[0014] The first power of the maximum peak value is determined, the second power of the first peak value is determined, and the third power of the second peak value is determined, wherein the maximum peak value is the peak value with the largest power in the power response graph corresponding to the maximum peak value, and the first peak value and the second peak value are two maximum peak values ​​that are adjacent to the maximum peak value in the power response graph.

[0015] Determine a first ratio between the first power and the fourth power, wherein the fourth power is the larger of the second power and the third power;

[0016] Based on the first correspondence and the first ratio, the absolute value of the first frequency offset estimate of the target PRACH signal is determined;

[0017] Wherein, the first correspondence includes a correspondence between at least one second ratio and at least one second frequency offset estimate, one second ratio corresponds to one second frequency offset estimate, and different second ratios correspond to different second frequency offset estimates; the first ratio is one of the at least one second ratio, and the first frequency offset estimate is one of the at least one second frequency offset estimate.

[0018] Optionally, according to a signal frequency offset estimation method of one embodiment of this application, determining the first power of the maximum peak value includes:

[0019] The power of the PRACH signal diffused at the adjacent taps of the maximum peak and the power of the PRACH signal at the maximum peak are added together to obtain the first power of the maximum peak.

[0020] Optionally, according to a signal frequency offset estimation method of one embodiment of this application, determining the second power of the first peak includes:

[0021] The power of the PRACH signal diffused at the adjacent taps of the first peak and the power of the PRACH signal at the first peak are added together to obtain the second power of the first peak.

[0022] Optionally, according to a signal frequency offset estimation method of one embodiment of this application, determining the third power of the second peak includes:

[0023] The power of the PRACH signal diffused at the adjacent taps of the second peak and the power of the PRACH signal at the second peak are added together to obtain the third power of the second peak.

[0024] Optionally, according to a signal frequency offset estimation method of one embodiment of this application, determining the sign of the first frequency offset estimate includes:

[0025] Based on the power relationship between the first peak and the second peak, and the magnitude of q, the sign of the first frequency offset estimate is determined;

[0026] Wherein, q is the expression that satisfies (qu) mod L RA = 1, where u is the physical index of the root sequence, and L is the smallest positive integer. RA is the length of the root sequence.

[0027] Optionally, according to a signal frequency offset estimation method of one embodiment of this application, determining the sign of the first frequency offset estimate based on the power relationship between the first peak and the second peak, and the magnitude of q, includes at least one of the following:

[0028] When q is less than L RA In half of the cases, if the second power is determined to be less than the third power, then the sign of the first frequency offset estimate is determined to be positive; or

[0029] When q is less than L RA In half of the cases, if the second power is determined to be greater than the third power, then the sign of the first frequency offset estimate is determined to be negative; or

[0030] Where q is not less than L RA Half of, and less than L RA In the case where the second power is determined to be less than the third power, the sign of the first frequency offset estimate is determined to be negative; or

[0031] Where q is not less than L RA Half of, and less than L RAIn the case where the second power is determined to be greater than the third power, the sign of the first frequency offset estimate is determined to be positive.

[0032] Secondly, embodiments of this application also provide a network-side device, including a memory, a transceiver, and a processor, wherein:

[0033] A memory for storing computer programs; a transceiver for sending and receiving data under the control of the processor; and a processor for reading the computer programs from the memory and performing the following operations:

[0034] Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0035] Based on the preambleID of the target PRACH signal among the one or more PRACH signals, the maximum peak power of the target PRACH signal is determined;

[0036] Based on the maximum peak power of the target PRACH signal, a first frequency offset estimate of the target PRACH signal is determined;

[0037] The maximum peak power is used to represent the received power of the PRACH signal.

[0038] Optionally, according to a network-side device of one embodiment of this application, determining the absolute value of the first frequency offset estimate includes:

[0039] The first power of the maximum peak value is determined, the second power of the first peak value is determined, and the third power of the second peak value is determined, wherein the maximum peak value is the peak value with the largest power in the power response graph corresponding to the maximum peak value, and the first peak value and the second peak value are two maximum peak values ​​that are adjacent to the maximum peak value in the power response graph.

[0040] Determine a first ratio between the first power and the fourth power, wherein the fourth power is the larger of the second power and the third power;

[0041] Based on the first correspondence and the first ratio, the absolute value of the first frequency offset estimate of the target PRACH signal is determined;

[0042] Wherein, the first correspondence includes a correspondence between at least one second ratio and at least one second frequency offset estimate, one second ratio corresponds to one second frequency offset estimate, and different second ratios correspond to different second frequency offset estimates; the first ratio is one of the at least one second ratio, and the first frequency offset estimate is one of the at least one second frequency offset estimate.

[0043] Optionally, according to a network-side device of one embodiment of this application, determining the second power of the first peak includes:

[0044] The power of the PRACH signal diffused at the adjacent taps of the first peak and the power of the PRACH signal at the first peak are added together to obtain the second power of the first peak.

[0045] Optionally, according to a network-side device of one embodiment of this application, determining the first power of the maximum peak includes:

[0046] The power of the PRACH signal diffused at the adjacent taps of the maximum peak and the power of the PRACH signal at the maximum peak are added together to obtain the first power of the maximum peak.

[0047] Optionally, according to a network-side device of one embodiment of this application, determining the third power of the second peak includes:

[0048] The power of the PRACH signal diffused at the adjacent taps of the second peak and the power of the PRACH signal at the second peak are added together to obtain the third power of the second peak.

[0049] Optionally, according to a network-side device of one embodiment of this application, determining the sign of the first frequency offset estimate includes:

[0050] Based on the power relationship between the first peak and the second peak, and the magnitude of q, the sign of the first frequency offset estimate is determined;

[0051] Wherein, q is the expression that satisfies (qu) mod L RA = 1, where u is the physical index of the root sequence, and L is the smallest positive integer. RA is the length of the root sequence.

[0052] Optionally, according to a network-side device of one embodiment of this application, determining the sign of the first frequency offset estimate based on the power relationship between the first peak and the second peak, and the magnitude of q, includes at least one of the following:

[0053] When q is less than L RA In half of the cases, if the second power is determined to be less than the third power, then the sign of the first frequency offset estimate is determined to be positive; or

[0054] When q is less than L RA In half of the cases, if the second power is determined to be greater than the third power, then the sign of the first frequency offset estimate is determined to be negative; or

[0055] Where q is not less than L RA Half of, and less than L RA In the case where the second power is determined to be less than the third power, the sign of the first frequency offset estimate is determined to be negative; or

[0056] Where q is not less than L RA Half of, and less than L RA In the case where the second power is determined to be greater than the third power, the sign of the first frequency offset estimate is determined to be positive.

[0057] Thirdly, embodiments of this application also provide a signal frequency offset estimation device, comprising:

[0058] A receiving unit, used to receive one or more Physical Random Access Channel (PRACH) signals sent by a terminal;

[0059] The processing unit is configured to determine the maximum peak power of the target PRACH signal based on the preambleID of the target PRACH signal in the one or more PRACH signals;

[0060] An estimation unit is used to determine a first frequency offset estimate of the target PRACH signal based on the maximum peak power of the target PRACH signal;

[0061] The maximum peak power is used to represent the received power of the PRACH signal.

[0062] Fourthly, embodiments of this application also provide a processor-readable storage medium storing a computer program for causing the processor to perform the method described in the first aspect.

[0063] The signal frequency offset estimation method, device, apparatus, and storage medium provided in this application can effectively distinguish the maximum peak power of different PRACH signals based on different preamble IDs after receiving one or more PRACH signals. This avoids the defect that the differential phase method cannot accurately estimate the frequency offset of PRACH signals due to the overlap between multiple received PRACH signals. Furthermore, it determines the first frequency offset estimate of the target PRACH signal based on the maximum peak power of the target PRACH signal, effectively improving the accuracy of frequency offset estimation for one or more received PRACH signals. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0065] Figure 1 This is a schematic diagram of the PRACH structure of the communication system provided in the embodiments of this application;

[0066] Figure 2 This is one of the flowcharts illustrating the signal frequency offset estimation method provided in the embodiments of this application;

[0067] Figure 3 This is a second schematic flowchart of the signal frequency offset estimation method provided in the embodiments of this application;

[0068] Figure 4 This is the third flowchart illustrating the signal frequency offset estimation method provided in the embodiments of this application;

[0069] Figure 5 This is the fourth flowchart illustrating the signal frequency offset estimation method provided in the embodiments of this application;

[0070] Figure 6 This is a schematic diagram of the ratio-frequency offset curve and its piecewise approximation curve;

[0071] Figure 7 This is a schematic diagram of the network-side device provided in an embodiment of this application;

[0072] Figure 8 This is a schematic diagram of the signal frequency offset estimation device provided in the embodiments of this application. Detailed Implementation

[0073] In the embodiments of this application, the term "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following associated objects have an "or" relationship.

[0074] In the embodiments of this application, the term "multiple" refers to two or more, and other quantifiers are similar.

[0075] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0076] The technical solutions provided in this application can be applied to various systems, especially 5G systems. For example, applicable systems include Global System for Mobile Communication (GSM), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA) General Packet Radio Service (GPRS), Long Term Evolution (LTE), LTE Frequency Division Duplex (FDD), LTE Time Division Duplex (TDD), Long Term Evolution Advanced (LTE-A), Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), and 5G New Radio (NR). All of these systems include terminal equipment and network equipment. The systems may also include a core network component, such as Evolved Packet System (EPS) and 5G systems (5GS).

[0077] The terminal devices involved in the embodiments of this application can be devices that provide voice and / or data connectivity to users, handheld devices with wireless connectivity, or other processing devices connected to a wireless modem. The names of the terminal devices may differ in different systems; for example, in a 5G system, a terminal device can be called a terminal or User Equipment (UE). Wireless terminal devices can communicate with one or more core networks (CNs) via a Radio Access Network (RAN). Wireless terminal devices can be mobile terminal devices, such as mobile phones (or "cellular" phones) and computers with mobile terminal devices, for example, portable, pocket-sized, handheld, computer-embedded, or vehicle-mounted mobile devices that exchange voice and / or data with the RAN. Examples include Personal Communication Service (PCS) phones, cordless phones, Session Initiated Protocol (SIP) phones, Wireless Local Loop (WLL) stations, and Personal Digital Assistants (PDAs). Wireless terminal equipment can also be referred to as a system, subscriber unit, subscriber station, mobile station, mobile station, remote station, access point, remote terminal, access terminal, user terminal, user agent, or user device, but is not limited to these terms in the embodiments of this application.

[0078] To facilitate a clearer understanding of the various embodiments of this application, some relevant background knowledge will be introduced as follows.

[0079] Figure 1 This is a schematic diagram of the PRACH structure of the communication system provided in the embodiments of this application, as shown below. Figure 1 As shown, the Physical Random Access Channel (PRACH) signal of a communication system consists of three parts: a cyclic prefix (CP), a sequence, and a guard slot (GP). The slot lengths occupied by these three parts are T, respectively. CPT SEQ and T GP CP represents a copy of the last segment of data in the Sequence.

[0080] The format of the PRACH signal defined by the 5G NR system is shown in Tables 1 and 2 below:

[0081] Table 1. Preamble format for random access, L RA =839, Δf RA ∈{1.25,5}kHz.

[0082]

[0083] Table 2 Preamble format for random access, L RA =139, Δf RA =15.2 μ kHz, μ∈{0,1,2,3}

[0084]

[0085]

[0086] In Tables 1 and 2, L RA Δf is the length of the ZC root sequence; RA N is the subcarrier spacing; u The first factor represents the total length of the preamble sequence. If it is in the form of a product, the first factor represents the number of times the preamble is repeated, and the second factor is the length of the repeated preamble. The length of the CP in the preamble sequence; is the length of the preamble sequence GP.

[0087] For received PRACH signals with frequency offset, the conventional method is to estimate the frequency offset using the differential phase method. The principle of the differential phase method is:

[0088] Assuming that in a PRACH signal, two data points s(t) and s(t+T) are identical at a time interval T, i.e., s(t) = s(t+T), and that the phase of the frequency offset Δf varies linearly with time at different times, then the data with frequency offset can be represented as s(t)·e j2πΔft and s(t+T)·e j2πΔf(t+T) If the time interval T between these two repeated data points does 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:

[0089] First, calculate the conjugate product (prod) of two repeated data points at time interval T. conj :

[0090] prod conj =conj(s(t)·e j2πΔft )·s(t+T)·e j2πΔf(t+T) =|s(t)| 2 ·e j2πΔfT

[0091] Then calculate the phase of the conjugate product, i.e., s(t)·e j2πΔft and s(t+T)·e j2πΔf(t+T) phase difference prod :

[0092] phase prod =atan(prod conj )=2πΔfT

[0093] Finally, the frequency offset Δf is calculated based on the phase difference:

[0094]

[0095] As can be seen from Tables 1 and 2, except for the preamble sequences in format 0 and C0, the preamble sequences in the other 11 formats all have repetitions. The frequency offset of preamble sequences with multiple repetitions can be estimated using the method described above. The format 0 preamble has no repetitions, but a segment of data in the CP and Sequence is identical. Therefore, the phase difference between corresponding samples in these two segments can be used to estimate the frequency offset.

[0096] Frequency offset is estimated by using the phase difference between the CP and a portion of the data in the corresponding Sequence. In the same time domain scenario (occasion), when the terminal transmits time domain signals through other channels such as PRACH or PUSCH, the time domain signals are superimposed and cannot be distinguished. In such a scenario where multiple user time domain signals overlap, the frequency offset estimated by the differential phase method has a large error or is even incorrect.

[0097] On the other hand, if the PRACH signal power is low and the noise power is high, even if there is only one PRACH signal in the received signal of the network-side equipment and no signals from other channels interfere with this PRACH signal, the frequency offset estimation result of the PRACH signal may still have a large error due to the influence of noise.

[0098] Moreover, the sampling rate of the time-domain received signal is relatively high, and the CP contains a large number of samples. 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 conjugate product of repeated data, then calculate the mean of the conjugate products of multiple repeated data, and finally use the mean to calculate the phase, and then calculate the frequency offset. The entire calculation process involves a large amount of computation.

[0099] To overcome the above-mentioned deficiencies, embodiments of this application provide a signal frequency offset estimation method, device, setup, and storage medium. The signal frequency offset estimation method, device, setup, and storage medium provided in embodiments of this application will be described exemplarily below.

[0100] Figure 2 This is one of the flowcharts illustrating the signal frequency offset estimation method provided in the embodiments of this application, such as... Figure 2 As shown, this application provides a signal frequency offset estimation method, the execution subject of which can be a network-side device. The method includes the following steps 210-230:

[0101] Step 210: Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0102] Step 220: Determine the maximum peak power of the target PRACH signal based on the preamble ID of the target PRACH signal in the one or more PRACH signals;

[0103] Specifically, the terminal UE can send one or more PRACH signals to the network-side device, and the network-side device can receive one or more PRACH signals sent by the UE. When the UE sends PRACH signals, the UE may be in a moving state. When the UE moves at a high speed, the Doppler effect is more severe, and the one or more PRACH signals received by the network-side device will have a large frequency offset. Therefore, the network-side device can perform frequency offset estimation for each of the one or more PRACH signals.

[0104] Specifically, in order to overcome the defect of large or even incorrect frequency offset estimation in scenarios where multiple user time-domain signals overlap, it is possible to consider not performing frequency offset estimation in the time domain.

[0105] Specifically, since the peak power positions of PRACH signals with different preamble IDs are different, after the network-side equipment receives one or more PRACH signals sent by the UE, it can distinguish the maximum peak values ​​of PRACH signals with different preamble IDs, and can more conveniently estimate the frequency offset of each PRACH signal in one or more PRACH signals.

[0106] Optionally, the PRACH signal from which frequency offset estimation is performed in one or more PRACH signals can be referred to as the target PRACH signal;

[0107] Specifically, the maximum peak power is used to represent the received power of the target PRACH signal;

[0108] Optionally, the location of the peak power of the target PRACH signal can be determined based on the preambleID of the target PRACH signal, thereby obtaining the maximum peak power of the target PRACH signal;

[0109] Specifically, the maximum peak power of the target PRACH signal refers to the power of the power function of the target PRACH signal at a certain point, which is greater than or equal to the power at any other point near that point, wherein the power function is monotonically increasing to the left of that point and monotonically decreasing to the right of that point;

[0110] For example, when a network-side device receives two PRACH signals sent by a UE, it can perform autocorrelation sequence processing on the PRACH signals. After processing, it can determine that the maximum peak value included in one or more received PRACH signals is PK. a1 PK a2 PK a3 PK b1 PK b2 and PK b3 Among them, PK a1 PK a2 and PK a3 These are the three maximum peak values ​​of the PRACH signal with preambleID a, PK. b1 PK b2 and PK b3 These are the three maxima peaks of the PRACH signal with preambleID b. After distinguishing the maxima peaks of the PRACH signals with preambleIDs a and b, the PRACH signal with preambleID a can be determined as the target PRACH signal. Then, based on the preambleID of the target PRACH signal, the maxima peaks PK of the processed PRACH signal can be analyzed. a1 PK a2 PK a3 PK b1 PK b2 and PK b3 From the power, obtain the maximum peak power P of the target PRACH signal with preambleID a. a1 P a2 and P a3 ;

[0111] Step 230: Based on the maximum peak power of the target PRACH signal, determine the first frequency offset estimate of the target PRACH signal;

[0112] The maximum peak power is used to represent the received power of the PRACH signal.

[0113] Specifically, when determining the received power of the target PRACH signal, the received power of the PRACH signal can be represented by the maximum peak power of the PRACH signal. Furthermore, based on the correspondence between the maximum peak power of the target PRACH signal and the frequency offset, the first frequency offset estimate of the target PRACH signal can be determined.

[0114] For example, P can be obtained through calculation. a1 With P a2 The first ratio is used to find the correspondence between the first ratio and the absolute value of the frequency offset to determine the first frequency offset estimate, where P a1 For the maximum peak power, P a2 This is the second highest peak power.

[0115] Optionally, the network-side equipment can be a base station or a network node; this application embodiment does not limit this.

[0116] The signal frequency offset estimation method provided in this application can effectively distinguish the maximum peak power of different PRACH signals based on different preamble IDs after receiving one or more PRACH signals. This avoids the defect that the differential phase method cannot accurately estimate the frequency offset of PRACH signals due to the overlap between multiple received PRACH signals. Furthermore, it determines the first frequency offset estimate of the target PRACH signal based on the maximum peak power of the target PRACH signal, effectively improving the accuracy of frequency offset estimation for one or more received PRACH signals.

[0117] Optionally, based on the maximum peak power of the target PRACH signal, a first frequency offset estimate of the target PRACH signal is determined, including:

[0118] Determine the absolute value of the first frequency offset estimate;

[0119] Determine the sign of the first frequency offset estimate.

[0120] Specifically, when the UE sends the target PRACH signal to the network-side device, the Doppler effect will cause the frequency of the received PRACH signal to shift positively or negatively. Therefore, the absolute value of the first frequency offset estimate can be determined to characterize the magnitude of the frequency change; the sign of the first frequency offset estimate can be determined to characterize the positive or negative frequency offset.

[0121] For example, a UE can send a target PRACH signal to a network-side device. The frequency of the target PRACH signal is f1. When the UE sends the target PRACH signal to the network-side device, the UE moves towards the network-side device at a speed of v. Due to the Doppler effect on the target PRACH signal, the frequency of the target PRACH signal received by the network-side device can be f2. For the network-side device, it can estimate the absolute value of the frequency offset of the received target PRACH signal, such as Δf. At this time, the network-side device does not know whether the frequency f1 of the target PRACH signal sent by the UE is greater than f2 by Δf or less than f2 by Δf. Therefore, it can determine the sign of the frequency offset. For example, if the sign of Δf is positive, f2 is greater than f1 by Δf. When compensating for the frequency of the received PRACH signal, the frequency f2 should be subtracted from Δf.

[0122] The signal frequency offset estimation method provided in this application can more accurately estimate the frequency offset of the PRACH signal by determining the absolute value and sign of the estimated PRACH signal frequency offset, thus providing a reference value for subsequent frequency offset compensation of the received signal.

[0123] Optionally, determining the absolute value of the first frequency offset estimate includes:

[0124] The first power of the maximum peak is determined, the second power of the first peak is determined, and the third power of the second peak is determined. The maximum peak is the peak with the largest power in the power response graph corresponding to the maximum peak power. The first peak and the second peak are the two maximum peaks that are adjacent to the maximum peak in the power response graph.

[0125] Determine a first ratio between the first power and the fourth power, wherein the fourth power is the larger of the second power and the third power;

[0126] Based on the first correspondence and the first ratio, determine the absolute value of the first frequency offset estimate of the target PRACH signal;

[0127] The first correspondence includes a correspondence between at least one second ratio and at least one second frequency offset estimate, where one second ratio corresponds to one second frequency offset estimate, and different second ratios correspond to different second frequency offset estimates; the first ratio is one of at least one second ratio, and the first frequency offset estimate is one of at least one second frequency offset estimate.

[0128] Specifically, after determining the maximum peak power of the target PRACH signal, the maximum peak power in the power response graph corresponding to the maximum peak power can be determined as the maximum peak power, and the power corresponding to the maximum peak power is the first power.

[0129] Specifically, after determining the first power, the maximum peak value that is adjacent to the left of the maximum peak value can be determined as the first peak value, and the power of the first peak value is the second power.

[0130] Specifically, after determining the second power, the maximum peak value adjacent to the right of the maximum peak value can be determined as the second peak value, and the power of the second peak value is the third power.

[0131] Specifically, after determining the third power, the larger of the second and third power can be determined as the fourth power, and then the ratio between the first power and the fourth power can be determined as the first ratio.

[0132] Specifically, after determining the first ratio, since the frequency offset causes the maximum peak power of the received PRACH signal to disperse at equal intervals, with the power dissipating less the farther away from the maximum peak, there is a correspondence between the first ratio and the absolute value of the frequency offset under the influence of the frequency offset. Therefore, the absolute value of the first frequency offset estimate of the target PRACH signal can be determined based on the first correspondence and the first ratio. The first correspondence can be an expression, a table, or a piecewise function.

[0133] For example, the absolute value of the first frequency offset estimate of the target PRACH signal can be determined by an expression relating the first ratio to the absolute value of the frequency offset.

[0134] Specifically, when the absolute value of the PRACH signal frequency offset Δf0 is less than the subcarrier spacing Δf RA When the frequency is 1 / 2, the position of the maximum peak value is fixed and does not change with the frequency offset, but the first ratio between the first power and the fourth power will change with the frequency offset, and there is a corresponding relationship.

[0135] The power |R(m)| of the m-th tap in the correlation sequence 2 for:

[0136]

[0137] Among them, L RA For ZC sequence length, L is the length of the PRACH format0 sequence. RA =839; u is the physical index of the ZC root sequence, with a value range of 1 to 838; normalized frequency offset Δf = Δf0 / Δf RA Δf0 is the actual frequency offset, Δf RA The subcarrier spacing for PRACH is in Hz.

[0138] Taking the normalized frequency offset Δf in the range of -0.5 < Δf < 0.5 as an example, the maximum value of the correlated sequence power occurs at m = 0, that is, the first power p of the maximum peak value.real :

[0139]

[0140] In a power-related sequence, the theoretical formula for calculating the ratio of the first power to the fourth power is:

[0141]

[0142] Among them, P -du For the second power, P du It is the third power;

[0143] As can be seen from the above formula, the first ratio peak ratio It is a function of the normalized frequency offset Δf. From equation (3), we can deduce the expression for |Δf|, that is:

[0144]

[0145] Therefore, the first ratio can be input into formula (4) to calculate the corresponding |Δf|, and then according to |Δf0|=|Δf|*Δf RA The absolute value of the frequency offset, |Δf0|, is determined, which is the absolute value of the first frequency offset estimate.

[0146] For example, the absolute value of the first frequency offset estimate of the target PRACH signal can be determined by using a pre-stored table between the first ratio and the absolute value of the frequency offset;

[0147] Specifically, the format0 subcarrier spacing can be Δf RA =1250Hz, with the upper limit of the normalized frequency offset set to 0.5, correspondingly, the absolute value of the frequency offset |Δf0| ranges from 0 to 0.5*Δf RA The value range is 0 to 0.5*Δf RA Sampling is performed uniformly at certain intervals, for example, at 10Hz intervals. The normalized frequency offset |Δf| of the independent variable then takes the value Δf = 0.008 * k (where k = 1, ..., 62). Substituting these |Δf| values ​​into formula (3), the corresponding first ratio peak is obtained through calculation. ratio After obtaining the first ratio peak ratio Then, for all values ​​of |Δf|, the absolute value of the corresponding frequency offset |Δf0| = 10k, and their corresponding first ratio peak, ratio Stored as a two-dimensional table, as shown in Table 3 below:

[0148] Table 3. Comparison of the absolute value of frequency deviation with the first ratio, Δf RA =1.25kHz.

[0149]

[0150]

[0151] For example, the absolute value of the first frequency offset estimate of the target PRACH signal can be determined by a piecewise function between the first ratio and the absolute value of the frequency offset;

[0152] Specifically, based on a pre-stored table, a set of |Δf| values ​​and their corresponding first ratio peak can be obtained. ratio To ensure calculation accuracy, the sampling interval of |Δf| can be as small as possible, and then the first ratio peak is used. ratio That is, the ratio of the maximum peak power to the second largest peak power, represented on the horizontal axis, with the first ratio being peak. ratio The corresponding |Δf| value, i.e., the normalized frequency offset, is used as the ordinate. Plot the corresponding points on the coordinate system, then connect adjacent points to obtain a line graph. Next, fit a piecewise function to this line graph to finally obtain the curve of the first ratio versus the normalized frequency offset. The piecewise function can be as follows:

[0153]

[0154] The signal frequency offset estimation method provided in this application can avoid the defect that the differential phase method cannot accurately estimate the frequency offset of the PRACH signal due to the overlap between multiple PRACH received signals, and effectively improve the accuracy of frequency offset estimation for one or more received PRACH signals. At the same time, the frequency offset is estimated based on the first ratio between the maximum peak power and the fourth power to determine the first frequency offset estimate of the target PRACH signal, which to some extent offsets the influence of noise on the frequency offset estimation. Moreover, the absolute value of the frequency offset is determined by an expression, table or piecewise function, without the need to calculate the differential phase of multiple sampling points, which is simple to implement and has a small computational load.

[0155] Optionally, determining the first power of the maximum peak value includes:

[0156] The power of the PRACH signal diffused at the adjacent taps of the maximum peak and the power of the PRACH signal at the maximum peak are added together to obtain the first power of the maximum peak.

[0157] Specifically, when calculating the first power of the maximum peak, in order to eliminate the power diffusion effect caused by time delay, the power diffused on the adjacent taps of the maximum peak can be accumulated to the power of the maximum peak to obtain a more accurate first power of the maximum peak.

[0158] The signal frequency offset estimation method provided in this application calculates the first power of the maximum peak value by adding the power diffused on the left and right adjacent taps to the corresponding maximum peak power, which can eliminate the power diffusion effect caused by time delay to a certain extent.

[0159] Optionally, determining the second power of the first peak includes:

[0160] The power of the PRACH signal diffused at the adjacent taps of the first peak is added to the power of the PRACH signal at the first peak to obtain the second power of the first peak.

[0161] Specifically, when calculating the second power of the first peak, in order to eliminate the power dispersion effect caused by the time delay, the power dispersed on the adjacent taps of the first peak can be accumulated to the power of the first peak to obtain a more accurate second power of the first peak.

[0162] The signal frequency offset estimation method provided in this application calculates the second power of the first peak by adding the power diffused on the left and right adjacent taps to the second power of the corresponding first peak, which can eliminate the power diffusion effect caused by time delay to a certain extent.

[0163] Optionally, determining the third power of the second peak includes:

[0164] The power of the PRACH signal diffused at the adjacent tap of the second peak and the power of the PRACH signal on the second peak are added together to obtain the third power of the second peak.

[0165] Specifically, when calculating the third power of the second peak, in order to eliminate the power diffusion effect caused by the time delay, the power diffused at the adjacent taps of the second peak can be added to the power of the second peak to obtain a more accurate third power of the second peak.

[0166] The signal frequency offset estimation method provided in this application calculates the third power of the second peak by adding the useful power dispersed on the left and right adjacent taps to the third power of the second peak, which can eliminate the power dispersion effect caused by time delay to a certain extent.

[0167] Optionally, determining the sign of the first frequency offset estimate includes:

[0168] Based on the power relationship between the first and second peak values, and the magnitude of q, the sign of the first frequency offset estimate is determined;

[0169] Where q is the expression that satisfies (qu) mod L RA = 1, the smallest positive integer, u is the physical index of the root sequence, L RA is the length of the root sequence.

[0170] Specifically, at higher UE movement speeds, the Doppler effect is more pronounced, resulting in significant frequency shifts. The preamble of the PRACH sequence is a Zadoff-Chu sequence, and this frequency shift causes the correlated peak power of the ZC sequence to deviate by d... u The power is a multiple of the equal-distance dispersion, and the power dispersed decreases with increasing distance from the maximum peak value. Where d u It can be calculated from the physical index u of the ZC root sequence. The specific calculation method is as follows:

[0171] First find the condition that satisfies (qu) mod L. RA Find the smallest positive integer q that equals 1, and then calculate d according to the following formula. u ,

[0172]

[0173] Where, d u The value is the interval between the maximum peak and the adjacent maximum peak, -d u The corresponding peak value is the first peak value, d u The corresponding peak is the second peak, u is the physical index of the root sequence, and L RA The length of the root sequence;

[0174] Specifically, when the absolute value of the PRACH signal frequency offset Δf is less than the subcarrier spacing Δf RA At 1 / 2, the location of the maximum peak value does not change with frequency offset and remains fixed, but the maximum peak power is located at an integer multiple of d. u The sub-peak power at a given location changes with frequency offset, and follows a certain pattern. When the frequency offset is positive, the power at the interval d from the maximum peak position... u The second peak at that point is greater than the interval -d. u The first peak at the point, when the frequency offset is negative, d u The second peak at that point is less than -d u The first peak value at that point can be used to determine the sign of the frequency offset based on this pattern;

[0175] For example, when Δf > 0, the second largest peak occurs at m = q, where m is the position of the m-th tap, i.e.:

[0176]

[0177] Where Δf is the normalized frequency offset Δf = Δf0 / Δf RA The value range is 0 < |Δf| < 0.5; Δf0 is the actual frequency offset, Δf RA P represents the subcarrier spacing of PRACH, all in Hz; qLet R(q) be the power of the q-th tap, and R(q) be the signal function of the q-th tap.

[0178] When Δf < 0, the second largest peak occurs at m = L. RA At the -q position, that is:

[0179]

[0180] Where, p -q For the Lth RA -q taps power, R(L RA -q) is the Lth RA -q tap signal functions;

[0181] According to d u The relationship with q can be obtained as follows:

[0182]

[0183] Therefore, the sign of the first frequency offset estimate can be determined based on the power relationship between the first and second peak values, and the magnitude of q.

[0184] The signal frequency offset estimation method provided in this application, based on determining the positions of the second largest peak and the largest peak, and by judging the power relationship between the first peak and the second peak, as well as the value of q, can determine the sign of the first frequency offset estimate, providing a basis for judging the positive or negative sign of the frequency offset.

[0185] Optionally, based on the power relationship between the first peak and the second peak, and the magnitude of q, the sign of the first frequency offset estimate is determined, including at least one of the following:

[0186] When q is less than L RA In half of the cases, if the second power is determined to be less than the third power, then the sign of the first frequency offset estimate is determined to be positive; or

[0187] When q is less than L RA In half of the cases, if the second power is determined to be greater than the third power, then the sign of the first frequency offset estimate is determined to be negative; or

[0188] When q is not less than L RA Half of L, and less than L RA In the case where the second power is determined to be less than the third power, the sign of the first frequency offset estimate is determined to be negative; or

[0189] When q is not less than L RA Half of L, and less than L RA In the case where the second power is determined to be greater than the third power, the sign of the first frequency offset estimate is determined to be positive.

[0190] Specifically, when q is less than L RA In half of the cases, if the second power is less than the third power, the sign of the first frequency offset estimate can be determined to be positive; if the second power is greater than the third power, the sign of the first frequency offset estimate can be determined to be negative.

[0191] Specifically, when q is not less than L RA Half of L, and less than L RA In the case where the second power is less than the third power, the sign of the first frequency offset estimate can be determined to be negative; if the second power is greater than the third power, the sign of the first frequency offset estimate can be determined to be positive.

[0192] For example, when Δf>0, p can be calculated according to formula (7). q ;

[0193] When Δf < 0, p can be calculated according to formula (8). -q ;

[0194] Combining formulas (9) and (10), we can obtain:

[0195] When q is less than L RA When half of it, if Then it can be determined that the sign of the first frequency offset estimate is positive; if Then it can be determined that the sign of the first frequency offset estimate is negative;

[0196] When q is not less than L RA Half of L, and less than L RA At that time, if Then it can be determined that the sign of the first frequency offset estimate is negative; if Then it can be determined that the sign of the first frequency offset estimate is positive.

[0197] The signal frequency offset estimation method provided in this application determines the sign of the first frequency offset estimate by judging the power relationship between the first peak and the second peak, as well as the magnitude of q.

[0198] Figure 3 This is a second schematic flowchart of the signal frequency offset estimation method provided in the embodiments of this application, as shown below. Figure 3 As shown, this application provides a signal frequency offset estimation method, the execution subject of which can be a network-side device. The method includes the following steps 310-340:

[0199] Step 310: Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0200] Step 320: Based on the preambleID of the target PRACH signal, determine the maximum peak value of the target PRACH signal and the two secondary peak values ​​adjacent to the maximum peak value;

[0201] Specifically, the position of the maximum peak of the target PRACH signal can be determined based on the preambleID of the target PRACH signal, and then the two secondary peaks adjacent to the maximum peak can be determined.

[0202] Step 330: Based on the expression corresponding to the absolute value of the first ratio and the frequency offset, determine the absolute value of the first frequency offset estimate of the target PRACH signal;

[0203] Specifically, after determining the maximum peak value and two secondary peak values, the corresponding first power, second power and third power can be determined, and then the larger of the second power and third power can be obtained as the fourth power, and then the ratio of the first power to the fourth power can be obtained as the first ratio.

[0204] Specifically, in order to eliminate the power dispersion effect caused by time delay when calculating power, the power dispersed on the adjacent taps of the peak can be added to the power of the peak to obtain a more accurate power.

[0205] Specifically, after determining the first ratio, the absolute value of the first frequency offset estimate of the target PRACH signal can be determined based on the expression corresponding to the first ratio and the absolute value of the frequency offset.

[0206] For example, when the absolute value of the PRACH signal frequency offset Δf0 is less than the subcarrier spacing Δf RA When the frequency is 1 / 2, the position of the maximum peak value is fixed and does not change with the frequency offset, but the first ratio between the first power and the fourth power will change with the frequency offset, and there is a corresponding relationship.

[0207] Specifically, the first ratio can be input into formula (4) to calculate the corresponding |Δf|, and then according to |Δf0|=|Δf|*Δf RA The absolute value of the frequency offset, |Δf0|, is determined, which is the absolute value of the first frequency offset estimate.

[0208] Step 340: Determine the sign of the first frequency offset estimate;

[0209] Specifically, d can be calculated according to formula (6). u Then, the sign of the first frequency offset estimate is determined by combining Δf;

[0210] For example, when Δf>0, p can be calculated according to formula (7). q ;

[0211] When Δf < 0, p can be calculated according to formula (8). -q ;

[0212] Combining formulas (9) and (10), we can obtain:

[0213] When q is less than L RA When half of it, if Then the sign of the first frequency offset estimate is determined to be positive; if Then the sign of the first frequency offset estimate is determined to be negative;

[0214] When q is not less than L RA Half of L, and less than L RA At that time, if Then the sign of the first frequency offset estimate is determined to be negative; if Then the sign of the first frequency offset estimate is determined to be positive.

[0215] The signal frequency offset estimation method provided in this application can avoid the defect that the differential phase method cannot accurately estimate the frequency offset of the PRACH signal due to the overlap between multiple PRACH received signals, effectively improving the accuracy of frequency offset estimation for one or more received PRACH signals; at the same time, the frequency offset is estimated based on the first ratio between the maximum peak power and the fourth power to determine the first frequency offset estimate of the target PRACH signal, which to some extent offsets the influence of noise on the frequency offset estimation; and the corresponding frequency offset estimate can be quickly calculated through the expression without calculating the differential phase of multiple sampling points, making the implementation simple and computationally intensive.

[0216] Figure 4 This is the third flowchart illustrating the signal frequency offset estimation method provided in the embodiments of this application, as shown below. Figure 4 As shown, this application provides a signal frequency offset estimation method, the execution subject of which can be a network-side device. The method includes the following steps 410-440:

[0217] Step 410: Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0218] Step 420: Based on the preambleID of the target PRACH signal, determine the maximum peak value of the target PRACH signal and the two secondary peak values ​​adjacent to the maximum peak value;

[0219] Specifically, the position of the maximum peak of the target PRACH signal can be determined based on the preambleID of the target PRACH signal, and then the two secondary peaks adjacent to the maximum peak can be determined.

[0220] Step 430: Based on the pre-stored table, determine the absolute value of the first frequency offset estimate of the target PRACH signal;

[0221] Specifically, after determining the maximum peak value and two secondary peak values, the corresponding first power, second power and third power can be determined, and then the larger of the second power and third power can be obtained as the fourth power, and then the ratio of the first power to the fourth power can be obtained as the first ratio.

[0222] Specifically, in order to eliminate the power dispersion effect caused by time delay when calculating power, the power dispersed on the adjacent taps of the peak can be added to the power of the peak to obtain a more accurate power.

[0223] Specifically, after determining the first ratio, the absolute value of the first frequency offset estimate of the target PRACH signal can be determined based on Table 3;

[0224] Specifically, determining the absolute value of the frequency offset may include steps 431-434:

[0225] Step 431: Determine the locations of the maximum and second-highest peak values;

[0226] Specifically, among the maxima, the peak with the highest power can be searched as the maximum peak, and the position of the maximum peak can be denoted as index0, with a distance of ±d from the position of the maximum peak. u The positions of the two secondary peaks are as follows:

[0227]

[0228] Step 432: Determine the first power and the fourth power;

[0229] Specifically, the power of the maximum peak and the two adjacent secondary peaks can be obtained by measuring the power of the maximum peak. The first power of the maximum peak is denoted as P. real Distance from the maximum peak position ±d u The power of the two sub-peak values ​​are P du and P -du ;

[0230] Step 433: Calculate the first ratio between the first power and the fourth power;

[0231] Specifically, the first ratio peak can be calculated using formula (3). ratio ;

[0232] Step 434: Obtain an estimate of the absolute value of the frequency offset;

[0233] Specifically, the calculated peak ratioCompare each value with the first value in the table, starting from the first one, and find the values ​​in the table that are less than the peak. ratio The index of the first pre-stored ratio is used to output the absolute value of the frequency offset, |Δf|. The data stored in the table is 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:

[0234]

[0235] After calculating |Δf|, we can use the formula |Δf0|=|Δf|*Δf RA The absolute value of the frequency offset, |Δf0|, is determined, which is the absolute value of the first frequency offset estimate.

[0236] Step 440: Determine the sign of the first frequency offset estimate.

[0237] Specifically, d can be calculated according to formula (6). u Then, the sign of the first frequency offset estimate is determined by combining Δf;

[0238] For example, when Δf>0, p can be calculated according to formula (7). q ;

[0239] When Δf < 0, p can be calculated according to formula (8). -q ;

[0240] Combining formulas (9) and (10), we can obtain:

[0241] When q is less than L RA When half of it, if Then it can be determined that the sign of the first frequency offset estimate is positive; if Then it can be determined that the sign of the first frequency offset estimate is negative;

[0242] When q is not less than L RA Half of L, and less than L RA At that time, if Then it can be determined that the sign of the first frequency offset estimate is negative; if Then it can be determined that the sign of the first frequency offset estimate is positive.

[0243] The signal frequency offset estimation method provided in this application can avoid the defect that the differential phase method cannot accurately estimate the frequency offset of the PRACH signal due to the overlap between multiple PRACH received signals, effectively improving the accuracy of frequency offset estimation for one or more received PRACH signals. At the same time, the frequency offset is estimated based on the first ratio between the maximum peak power and the fourth power to determine the first frequency offset estimate of the target PRACH signal, which to some extent offsets the influence of noise on the frequency offset estimation. Moreover, the corresponding frequency offset estimate can be quickly determined through a pre-stored table, without the need to calculate the differential phase of multiple sampling points, making the implementation simple and computationally intensive.

[0244] Figure 5 This is the fourth flowchart illustrating the signal frequency offset estimation method provided in the embodiments of this application, as shown below. Figure 5 As shown, this application provides a signal frequency offset estimation method, the execution subject of which can be a network-side device, and the method includes the following steps 510-540.

[0245] Step 510: Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0246] Step 520: Based on the preambleID of the target PRACH signal, determine the maximum peak value of the target PRACH signal and the two secondary peak values ​​adjacent to the maximum peak value;

[0247] Specifically, the position of the maximum peak of the target PRACH signal can be determined based on the preambleID of the target PRACH signal, and then the two secondary peaks adjacent to the maximum peak can be determined.

[0248] Step 530: Based on the piecewise function corresponding to the absolute value of the first ratio and the frequency offset, determine the absolute value of the first frequency offset estimate of the target PRACH signal;

[0249] Specifically, after determining the maximum peak value and two secondary peak values, the corresponding first power, second power and third power can be determined, and then the larger of the second power and third power can be obtained as the fourth power, and then the ratio of the first power to the fourth power can be obtained as the first ratio.

[0250] Specifically, in order to eliminate the power dispersion effect caused by time delay when calculating power, the power dispersed on the adjacent taps of the peak can be added to the power of the peak to obtain a more accurate power.

[0251] Specifically, after determining the first ratio, the absolute value of the first frequency offset estimate of the target PRACH signal can be determined based on the piecewise function corresponding to the absolute value of the first ratio and the absolute value of the frequency offset.

[0252] For example, after obtaining formula (3), the normalized frequency offset |Δf| can be deduced from formula (3) to be the first ratio peak. ratio The functional expression of is formula (4);

[0253] Specifically, after deriving formula (4), the function expression can be fitted as a piecewise function, including steps 531-533:

[0254] Step 531: Calculate the normalized frequency offset;

[0255] Specifically, the coefficients of each piecewise function and the corresponding interval of the first ratio can be stored. The first ratio is substituted into the piecewise function expression of the corresponding interval to calculate the normalized frequency offset |Δf|.

[0256] Step 532: Determine the absolute value of the frequency offset;

[0257] Specifically, after calculating the normalized frequency offset |Δf|, we can use the formula |Δf0|=|Δf|*Δf RA Calculate the absolute value of the frequency offset |Δf0|;

[0258] Step 533: Fit a piecewise function;

[0259] Specifically, piecewise function fitting can be performed using formula (5). Figure 6 This is a schematic diagram of the ratio-frequency offset curve and its piecewise approximation curve, such as... Figure 6 As shown, with the first ratio peak ratio That is, the ratio of the maximum peak power to the second largest peak power, represented on the horizontal axis, with the first ratio being peak. ratio The corresponding |Δf| value, i.e. the normalized frequency offset, is used as the vertical axis. Plotting the fitted curve and the theoretical curve on the same coordinate system shows that the piecewise function fitted curve has a good fit with the theoretical curve.

[0260] Specifically, after obtaining the fitted curve, the normalized frequency offset can be obtained based on the abscissa of the first ratio on the curve, and then based on |Δf0|=|Δf|*Δf RA The absolute value of the frequency offset, |Δf0|, is determined to be the absolute value of the first frequency offset estimate.

[0261] 540. Determine the sign of the first frequency offset estimate.

[0262] Specifically, d can be calculated according to formula (6). u Then, the sign of the first frequency offset estimate is determined by combining Δf;

[0263] For example, when Δf>0, p can be calculated according to formula (7). q ;

[0264] When Δf < 0, p can be calculated according to formula (8). -q ;

[0265] Combining formulas (9) and (10), we can obtain:

[0266] When q is less than L RA When it is half, if Then it can be determined that the sign of the first frequency offset estimate is positive; if Then it can be determined that the sign of the first frequency offset estimate is negative;

[0267] When q is not less than L RA Half of L, and less than L RA At that time, if Then it can be determined that the sign of the first frequency offset estimate is negative; if Then it can be determined that the sign of the first frequency offset estimate is positive.

[0268] The signal frequency offset estimation method provided in this application determines the absolute value of the first frequency offset estimate by determining a first ratio between the first power and the fourth power, and based on the correspondence between the first ratio and the absolute value of the first frequency offset estimate. This avoids the drawback of the differential phase method being unsuitable in scenarios where multiple PRACH signals overlap and cannot be distinguished in a time-domain channel. Furthermore, estimating the frequency offset based on the first ratio between the maximum peak power and the fourth power partially offsets the influence of noise on the frequency offset estimation. Moreover, by using a piecewise function fitting curve method, the corresponding frequency offset estimate can be quickly determined without calculating the differential phase of multiple sampling points, resulting in a simple implementation and low computational load.

[0269] This application provides a signal frequency offset estimation method and apparatus to address the problem that the differential phase method is inapplicable when multiple PRACH signals overlap and cannot be distinguished in a time-domain channel. The method and apparatus are based on the same concept and, since they solve similar problems, their implementations can be referenced interchangeably; repeated details will not be elaborated further.

[0270] Figure 7 This is a schematic diagram of the network-side device provided in the embodiments of this application, such as... Figure 7 As shown, the network-side device includes a memory 710, a transceiver 720, and a processor 730.

[0271] Wherein: memory 710 is used to store computer programs; transceiver 720 is used to send and receive data under the control of processor 730; processor 730 is used to read the computer program in memory 710 and perform the following operations:

[0272] Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0273] The maximum peak power of the target PRACH signal is determined based on the preambleID of the target PRACH signal among one or more PRACH signals.

[0274] Based on the maximum peak power of the target PRACH signal, determine the first frequency offset estimate of the target PRACH signal;

[0275] The maximum peak power is used to represent the received power of the PRACH signal.

[0276] Specifically, the transceiver 720 is used to receive and send data under the control of the processor 730.

[0277] Among them, Figure 7 In this context, the bus architecture can include any number of interconnected buses and bridges, specifically linking various circuits together, represented by one or more processors (processor 730) and memory (memory 710). The bus architecture can also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. The bus interface provides an interface. The transceiver 720 can be multiple elements, including transmitters and receivers, providing a unit for communicating with various other devices over transmission media, including wireless channels, wired channels, optical fibers, etc. The processor 730 is responsible for managing the bus architecture and general processing, and the memory 710 can store data used by the processor 730 during operation.

[0278] The processor 730 can be a central processing unit (CPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor can also adopt a multi-core architecture.

[0279] The network-side device provided in this application embodiment, after receiving one or more PRACH signals, can effectively distinguish the maximum peak power of different PRACH signals based on different preamble IDs. This avoids the defect that the differential phase method cannot accurately estimate the frequency offset of PRACH signals due to the overlap between multiple received PRACH signals. Based on the maximum peak power of the target PRACH signal, the first frequency offset estimate of the target PRACH signal is determined, effectively improving the accuracy of frequency offset estimation for one or more received PRACH signals.

[0280] Optionally, the processor 730 is also used for:

[0281] Determine the absolute value of the first frequency offset estimate;

[0282] Determine the sign of the first frequency offset estimate.

[0283] Optionally, the processor 730 is also used for:

[0284] The first power of the maximum peak is determined, the second power of the first peak is determined, and the third power of the second peak is determined. The maximum peak is the peak with the largest power in the power response graph corresponding to the maximum peak power. The first peak and the second peak are the two maximum peaks that are adjacent to the maximum peak in the power response graph.

[0285] Determine a first ratio between the first power and the fourth power, wherein the fourth power is the larger of the second power and the third power;

[0286] Based on the first correspondence and the first ratio, determine the absolute value of the first frequency offset estimate of the target PRACH signal;

[0287] The first correspondence includes a correspondence between at least one second ratio and at least one second frequency offset estimate, where one second ratio corresponds to one second frequency offset estimate, and different second ratios correspond to different second frequency offset estimates; the first ratio is one of at least one second ratio, and the first frequency offset estimate is one of at least one second frequency offset estimate.

[0288] Optionally, the processor 730 is also used for:

[0289] The power of the PRACH signal diffused at the adjacent taps of the maximum peak and the power of the PRACH signal at the maximum peak are added together to obtain the first power of the maximum peak.

[0290] Optionally, the processor 730 is also used for:

[0291] The power of the PRACH signal diffused at the adjacent taps of the first peak is added to the power of the PRACH signal at the first peak to obtain the second power of the first peak.

[0292] Optionally, the processor 730 is also used for:

[0293] The power of the PRACH signal diffused at the adjacent tap of the second peak and the power of the PRACH signal on the second peak are added together to obtain the third power of the second peak.

[0294] Optionally, the processor 730 is also used for:

[0295] Based on the power relationship between the first and second peak values, and the magnitude of q, the sign of the first frequency offset estimate is determined;

[0296] Where q is the expression that satisfies (qu) mod L RA = 1, the smallest positive integer, u is the physical index of the root sequence, L RA is the length of the root sequence.

[0297] Optionally, the processor 730 is also used for:

[0298] Determine the sign of the first frequency offset estimate, including at least one of the following:

[0299] When q is less than L RA In half of the cases, if we judge d u If the sign is positive, then the sign of the first frequency offset estimate is determined to be positive; or

[0300] When q is less than L RA In half of the cases, if we judge d u If the sign of the first frequency offset estimate is negative, then the sign of the first frequency offset estimate is determined to be negative; or

[0301] When q is not less than L RA Half of L, and less than L RA In the case of judging d u If the sign is positive, then the sign of the first frequency offset estimate is determined to be negative; or

[0302] When q is not less than L RA Half of L, and less than L RA In the case of judging d u If the sign of the first frequency offset estimate is negative, then the sign of the first frequency offset estimate is positive.

[0303] The network-side device provided in this application embodiment, after receiving one or more PRACH signals, can effectively distinguish the maximum peak power of different PRACH signals based on different preamble IDs. This avoids the defect that the differential phase method cannot accurately estimate the frequency offset of PRACH signals due to the overlap between multiple received PRACH signals. Based on the maximum peak power of the target PRACH signal, the first frequency offset estimate of the target PRACH signal is determined, effectively improving the accuracy of frequency offset estimation for one or more received PRACH signals.

[0304] It should be noted that the network-side device provided in this application embodiment can implement all the method steps implemented by the method embodiment with the network-side device as the execution subject, and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.

[0305] Figure 8 This is a schematic diagram of the signal frequency offset estimation device provided in the embodiments of this application, as shown below. Figure 8 As shown, the signal frequency offset estimation device includes: a receiving unit 810, a processing unit 820, and an estimation unit 830.

[0306] Wherein: the receiving unit 810 is used to receive one or more Physical Random Access Channel (PRACH) signals sent by the terminal;

[0307] The processing unit 820 is used to determine the maximum peak power of the target PRACH signal based on the preambleID of the target PRACH signal in one or more PRACH signals;

[0308] The estimation unit 830 is used to determine a first frequency offset estimate of the target PRACH signal based on the maximum peak power of the target PRACH signal;

[0309] The maximum peak power is used to represent the received power of the PRACH signal.

[0310] Specifically, the signal frequency offset estimation device can receive one or more Physical Random Access Channel (PRACH) signals sent by the terminal through the receiving unit 810; then the processing unit 820 can determine the maximum peak power of the target PRACH signal based on the preambleID of the target PRACH signal in one or more PRACH signals; finally, the estimation unit 830 can determine the first frequency offset estimate of the target PRACH signal based on the maximum peak power of the target PRACH signal.

[0311] The signal frequency offset estimation device provided in this application embodiment can effectively distinguish the maximum peak power of different PRACH signals based on different preamble IDs after receiving one or more PRACH signals. This avoids the defect that the differential phase method cannot accurately estimate the frequency offset of PRACH signals due to the overlap between multiple received PRACH signals. Based on the maximum peak power of the target PRACH signal, the first frequency offset estimate of the target PRACH signal is determined, which effectively improves the accuracy of frequency offset estimation for one or more received PRACH signals.

[0312] Optionally, the processing unit 820 is also used for:

[0313] Determine the absolute value of the first frequency offset estimate;

[0314] Determine the sign of the first frequency offset estimate.

[0315] Optionally, the processing unit 820 is also used for:

[0316] The first power of the maximum peak is determined, the second power of the first peak is determined, and the third power of the second peak is determined. The maximum peak is the peak with the largest power in the power response graph corresponding to the maximum peak power. The first peak and the second peak are the two maximum peaks that are adjacent to the maximum peak in the power response graph.

[0317] Determine a first ratio between the first power and the fourth power, wherein the fourth power is the larger of the second power and the third power;

[0318] Based on the first correspondence and the first ratio, determine the absolute value of the first frequency offset estimate of the target PRACH signal;

[0319] The first correspondence includes a correspondence between at least one second ratio and at least one second frequency offset estimate, where one second ratio corresponds to one second frequency offset estimate, and different second ratios correspond to different second frequency offset estimates; the first ratio is one of at least one second ratio, and the first frequency offset estimate is one of at least one second frequency offset estimate.

[0320] Optionally, the processing unit 820 is also used for:

[0321] The power of the PRACH signal diffused at the adjacent taps of the maximum peak and the power of the PRACH signal at the maximum peak are added together to obtain the first power of the maximum peak.

[0322] Optionally, the processing unit 820 is also used for:

[0323] The power of the PRACH signal diffused at the adjacent taps of the first peak is added to the power of the PRACH signal at the first peak to obtain the second power of the first peak.

[0324] Optionally, the processing unit 820 is also used for:

[0325] The power of the PRACH signal diffused at the adjacent tap of the second peak and the power of the PRACH signal on the second peak are added together to obtain the third power of the second peak.

[0326] Optionally, the processing unit 820 is also used for:

[0327] Based on the power relationship between the first and second peak values, and the magnitude of q, the sign of the first frequency offset estimate is determined;

[0328] Where q is the expression that satisfies (qu) mod L RA = 1, the smallest positive integer, u is the physical index of the root sequence, L RA is the length of the root sequence.

[0329] Optionally, the processing unit 820 is also used for:

[0330] Determine the sign of the first frequency offset estimate, including at least one of the following:

[0331] When q is less than L RA In half of the cases, if we judge d u If the sign is positive, then the sign of the first frequency offset estimate is determined to be positive; or

[0332] When q is less than L RA In half of the cases, if we judge d u If the sign of the first frequency offset estimate is negative, then the sign of the first frequency offset estimate is determined to be negative; or

[0333] When q is not less than L RA Half of L, and less than L RA In the case of judging d u If the sign is positive, then the sign of the first frequency offset estimate is determined to be negative; or

[0334] When q is not less than L RA Half of L, and less than L RA In the case of judging d u If the sign of the first frequency offset estimate is negative, then the sign of the first frequency offset estimate is positive.

[0335] The signal frequency offset estimation device provided in this application embodiment can effectively distinguish the maximum peak power of different PRACH signals based on different preamble IDs after receiving one or more PRACH signals. This avoids the defect that the differential phase method cannot accurately estimate the frequency offset of PRACH signals due to the overlap between multiple received PRACH signals. Based on the maximum peak power of the target PRACH signal, the first frequency offset estimate of the target PRACH signal is determined, which effectively improves the accuracy of frequency offset estimation for one or more received PRACH signals.

[0336] It should be noted that the signal frequency offset estimation device provided in this embodiment of the invention can implement all the method steps implemented by the method embodiment in which the execution subject is a network-side device, and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.

[0337] It should be noted that the division of units in the embodiments of this application is illustrative and only represents one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional units in the various embodiments of this application 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 units described above can be implemented in hardware or as software functional units.

[0338] 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 processor-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or 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 storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0339] On the other hand, embodiments of this application also provide a processor-readable storage medium storing a computer program for causing a processor to execute the methods provided in the above embodiments, including:

[0340] Receive one or more Physical Random Access Channel (PRACH) signals sent by the receiving terminal;

[0341] The maximum peak power of the target PRACH signal is determined based on the preambleID of the target PRACH signal among one or more PRACH signals.

[0342] Based on the maximum peak power of the target PRACH signal, determine the first frequency offset estimate of the target PRACH signal;

[0343] The maximum peak power is used to represent the received power of the PRACH signal.

[0344] Processor-readable storage media can be any available medium or data storage device that the processor can access, including but not limited to magnetic storage (e.g., floppy disks, hard disks, magnetic tapes, magneto-optical disks (MOs), etc.), optical storage (e.g., CDs, DVDs, BDs, HVDs, etc.), and semiconductor storage (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND flash), solid-state drives (SSDs)).

[0345] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0346] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0347] These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means, which are implemented in a process Figure 1One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0348] These processors can execute instructions that can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable device for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0349] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method of signal frequency offset estimation, the method comprising: The method comprises: receiving one or more physical random access channel (PRACH) signals sent by a terminal; determining a maximum peak power of a target PRACH signal among the one or more PRACH signals based on a preamble ID of the target PRACH signal; determining a first frequency offset estimation value of the target PRACH signal based on the maximum peak power of the target PRACH signal; wherein the maximum peak power represents a received power of the PRACH signal; the determining of the first frequency offset estimation value based on the maximum peak power of the target PRACH signal comprises: determining an absolute value of the first frequency offset estimation value; determining a sign of the first frequency offset estimation value; the determining of the absolute value of the first frequency offset estimation value comprises: determining a first power of a maximum peak, a second power of a first secondary peak, and a third power of a second secondary peak, wherein the maximum peak is a peak with the maximum power in a power response graph corresponding to the maximum peak power, the first secondary peak and the second secondary peak are two peaks adjacent to the left and right of the maximum peak in the power response graph, respectively; determining a first ratio between the first power and a fourth power, wherein the fourth power is a larger one of the second power and the third power; determining the absolute value of the first frequency offset estimation value of the target PRACH signal based on a first correspondence relationship and the first ratio; wherein the first correspondence relationship comprises a correspondence relationship between at least one second ratio and at least one second frequency offset estimation value, one second ratio corresponds to one second frequency offset estimation value, and different second ratios correspond to different second frequency offset estimation values; the first ratio is one of the at least one second ratio, and the first frequency offset estimation value is one of the at least one second frequency offset estimation value; the first correspondence relationship is determined based on the following formula: ； wherein denotes the normalized frequency offset, is the root sequence length, denotes the first ratio, the normalized frequency offset , the PRACH signal frequency offset has an absolute value less than half the subcarrier spacing .

2. The method of signal frequency offset estimation according to claim 1, characterized in that, the determining of the first power of the maximum peak comprises: accumulating the power of the PRACH signal diffused on adjacent taps of the maximum peak and the power of the PRACH signal on the maximum peak to obtain the first power of the maximum peak.

3. The method of signal frequency offset estimation according to claim 1, wherein, the determining of the second power of the first secondary peak comprises: accumulating the power of the PRACH signal diffused on adjacent taps of the first secondary peak and the power of the PRACH signal on the first secondary peak to obtain the second power of the first secondary peak.

4. The method of signal frequency offset estimation according to claim 1, wherein, the determining of the third power of the second secondary peak comprises: accumulating the power of the PRACH signal diffused on adjacent taps of the second secondary peak and the power of the PRACH signal on the second secondary peak to obtain the third power of the second secondary peak.

5. The method of signal frequency offset estimation according to claim 1, wherein, the determining of the sign of the first frequency offset estimation value comprises: determining the sign of the first frequency offset estimation value based on a power size relationship between the first secondary peak and the second secondary peak and a size of q; Wherein the To meet The u is a root sequence physical index, and the is a root sequence length.

6. The method of signal frequency offset estimation according to claim 5, wherein, The determining the sign of the first frequency offset estimation value based on the power size relationship between the first peak value and the second peak value and the size of q comprises at least one of the following: In the case that the first power is less than half of the second power, if it is judged that the second power is less than the third power, it is determined that the sign of the first frequency offset estimation value is positive; or In the case that the first power is less than half of the second power, if it is judged that the second power is less than the third power, it is determined that the sign of the first frequency offset estimation value is positive; or In the case that In the Smaller than the In half of the cases, if the second power is determined to be greater than the third power, then the sign of the first frequency offset estimate is determined to be negative; or In the Not less than the Half of, and less than the In the case where the second power is determined to be less than the third power, the sign of the first frequency offset estimate is determined to be negative; or In the Not less than the Half of, and less than the In the case where it is determined that the second power is greater than the third power, the sign of the first frequency offset estimate is determined to be positive. The maximum peak value is the maximum peak value in the power response graph corresponding to the maximum peak value, the first peak value and the second peak value are two maximum peak values adjacent to the left and right of the maximum peak value in the power response graph. 7.A network side device, comprising a memory, a transceiver, a processor; characterized in that, The memory is configured to store a computer program; the transceiver is configured to transceive data under the control of the processor; the processor is configured to read the computer program in the memory and perform the following operations: Receiving one or more physical random access channel (PRACH) signals sent by a terminal; Determining a maximum peak value power of a target PRACH signal among the one or more PRACH signals; Determining a first frequency offset estimation value of the target PRACH signal based on the maximum peak value power of the target PRACH signal; The maximum peak value power is used to represent the received power of the PRACH signal; The determining the first frequency offset estimation value of the target PRACH signal based on the maximum peak value power of the target PRACH signal comprises: Determining an absolute value of the first frequency offset estimation value; Determining a sign of the first frequency offset estimation value; The determining the absolute value of the first frequency offset estimation value comprises: Determining a first power of a maximum peak value, a second power of a first peak value, and a third power of a second peak value, wherein the maximum peak value is a peak value with the maximum power in a power response graph corresponding to the maximum peak value, and the first peak value and the second peak value are two maximum peak values adjacent to the left and right of the maximum peak value in the power response graph; Determining a first ratio between the first power and a fourth power, wherein the fourth power is a larger one of the second power and the third power; Determining an absolute value of the first frequency offset estimation value of the target PRACH signal based on a first corresponding relationship and the first ratio; The first corresponding relationship comprises a corresponding relationship between at least one second ratio and at least one second frequency offset estimation value, one second ratio corresponds to one second frequency offset estimation value, and different second ratios correspond to different second frequency offset estimation values; the first ratio is one of the at least one second ratio, and the first frequency offset estimation value is one of the at least one second frequency offset estimation value; The first corresponding relationship is determined based on the following formula: ； wherein denotes the normalized frequency offset, is the root sequence length, denotes the first ratio, the normalized frequency offset , the PRACH signal frequency offset is smaller than the subcarrier spacing is smaller than 1 / 2.

8. The network-side device of claim 7, wherein, The determining the first power of the maximum peak value comprises: The first power of the maximum peak value is obtained by accumulating the power of the PRACH signal diffused on the adjacent taps of the maximum peak value and the power of the PRACH signal on the maximum peak value.

9. The network-side device of claim 7, wherein, The determining the third power of the second peak value comprises: The third power of the second peak value is obtained by accumulating the power of the PRACH signal diffused on the adjacent taps of the second peak value and the power of the PRACH signal on the second peak value.

10. The network-side device of claim 7, wherein, The determining the second power of the first peak value comprises: accumulate power of the PRACH signal diffused on a tap adjacent to the first peak and power of the PRACH signal on the first peak to obtain a second power of the first peak.

11. The network-side device of claim 7, wherein, The determining the sign of the first frequency offset estimation value comprises: determining the sign of the first frequency offset estimation value based on a power size relationship between the first peak and the second peak and a size of q; Wherein the To meet The u is a root sequence physical index, and the The root sequence length.

12. The network-side device of claim 11, wherein, The determining the sign of the first frequency offset estimation value based on the power size relationship between the first peak and the second peak and the size of q comprises at least one of: In the case that the first power is less than half of the second power, if it is judged that the second power is less than the third power, it is determined that the sign of the first frequency offset estimation value is positive; or In the case that the first power is less than half of the second power, if it is judged that the second power is less than the third power, it is determined that the sign of the first frequency offset estimation value is positive; or In the case that In the case that the first power is less than half of the second power, if it is judged that the second power is greater than the third power, it is determined that the sign of the first frequency offset estimation value is negative; or In the case that the first power is less than half of the second power, if it is judged that the second power is greater than the third power, it is determined that the sign of the first frequency offset estimation value is negative; or In the case that In the Not less than the Half of, and less than the In the case where the second power is determined to be less than the third power, the sign of the first frequency offset estimate is determined to be negative; or In the Not less than the Half of, and less than the In the case where it is determined that the second power is greater than the third power, the sign of the first frequency offset estimate is determined to be positive. Wherein, a maximum peak adjacent to the left of the maximum peak is the first peak, and a maximum peak adjacent to the right of the maximum peak is the second peak.

13. A signal frequency offset estimation apparatus, characterized by comprising: Comprise: A receiving unit is configured to receive one or more physical random access channel (PRACH) signals sent by a terminal. A processing unit is configured to determine a maximum peak power of a target PRACH signal based on a preamble ID of the target PRACH signal in the one or more PRACH signals. An estimation unit is configured to determine a first frequency offset estimation value of the target PRACH signal based on the maximum peak power of the target PRACH signal. The maximum peak power is used to represent a received power of the PRACH signal. The determining the first frequency offset estimation value of the target PRACH signal based on the maximum peak power of the target PRACH signal comprises: determining an absolute value of the first frequency offset estimation value; determining a sign of the first frequency offset estimation value; The determining the absolute value of the first frequency offset estimation value comprises: determining a first power of a maximum peak, determining a second power of a first peak, and determining a third power of a second peak, wherein the maximum peak is a peak with the maximum power in a power response graph corresponding to the maximum peak power, the first peak and the second peak are two maximum peaks adjacent to the left and right of the maximum peak in the power response graph, respectively; determining a first ratio between the first power and a fourth power, wherein the fourth power is a larger one of the second power and the third power; determining an absolute value of the first frequency offset estimation value of the target PRACH signal based on a first corresponding relationship and the first ratio; The first corresponding relationship comprises a corresponding relationship between at least one second ratio and at least one second frequency offset estimation value, one second ratio corresponds to one second frequency offset estimation value, and different second ratios correspond to different second frequency offset estimation values; the first ratio is one of the at least one second ratio, and the first frequency offset estimation value is one of the at least one second frequency offset estimation value; The first corresponding relationship is determined based on the following formula: ； wherein denotes a normalized frequency offset, is a root sequence length, denotes a first ratio, the normalized frequency offset , the PRACH signal frequency offset has an absolute value less than a subcarrier spacing of 1 / 2.

14. A processor-readable storage medium, characterized in that, The processor readable storage medium stores a computer program, and the computer program is used to make the processor execute the method in any one of claims 1 to 6.

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