CN115051771A - Cell search method, device, equipment and computer storage medium - Google Patents

Abstract

The embodiments of the present application disclose a cell search method, device, equipment, and computer storage medium, wherein the method includes: performing a cross-correlation operation on first PSS frequency domain data and a local PSS sequence to obtain a first correlation sequence; The PSS frequency domain data is the PSS frequency domain data after the interference is eliminated from the received time domain data; based on the preset first time offset value, the time offset compensation is performed on the first transformed sequence after the discrete transform of the first correlation sequence, respectively, to obtain the first correlation compensation sequence; the information of the target cell is determined based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data; the first SSS frequency domain data is the SSS after interference is eliminated in the received time domain data frequency domain data. In the above manner, the problem of low cell search efficiency can be solved.

Description

Cell search method, device, device and computer storage medium

technical field

The embodiments of the present application relate to, but are not limited to, the field of communications technologies, and in particular, relate to a cell search method, apparatus, device, and computer storage medium.

Background technique

In a communication network system, after a terminal device is powered on, it first starts an initial search to search for a serving cell for camping. After the terminal device successfully camps on a serving cell, it will start a neighbor cell search. The main purpose of the neighbor cell search is to search for the neighbor cells of the serving cell and prepare for operations such as cell reselection or cell handover. At present, the solution for cell search needs further study.

SUMMARY OF THE INVENTION

Embodiments of the present application provide a cell search method, apparatus, device, and computer storage medium.

In a first aspect, an embodiment of the present application provides a cell search method, including:

Cross-correlation operation is performed on the first PSS frequency domain data and the local PSS sequence to obtain a first correlation sequence; the first PSS frequency domain data is the PSS frequency domain data after interference is eliminated from the received time domain data;

Based on the preset first time offset value, respectively perform time offset compensation on the first transformation sequence obtained by discrete transformation of the first correlation sequence to obtain a first correlation compensation sequence;

Based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data, the information of the target cell is determined; the first SSS frequency domain data is the SSS after interference cancellation in the received time domain data frequency domain data.

In a second aspect, an embodiment of the present application provides a cell search device, including:

a processing module, configured to perform a cross-correlation operation on the first PSS frequency domain data and the local PSS sequence to obtain a first correlation sequence; the first PSS frequency domain data is the PSS frequency domain data after the received time domain data is interfered with;

a compensation module, configured to perform time offset compensation on the first transformation sequence obtained by discrete transformation of the first correlation sequence based on a preset first time offset value, to obtain a first correlation compensation sequence;

a determining module, configured to determine the information of the target cell based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data; the first SSS frequency domain data is one of the received time domain data SSS frequency domain data after interference removal.

In a third aspect, an embodiment of the present application provides a device, the device includes: a processor and a memory,

the memory stores a computer program executable on the processor,

When the processor executes the program, the method according to the first aspect is implemented.

In a fourth aspect, an embodiment of the present application provides a computer storage medium, where the computer storage medium stores a computer program, and when the computer program is executed by a processor, the method described in the first aspect is implemented.

In the embodiment of the present application, the cross-correlation operation is performed on the first PSS frequency domain data and the local PSS sequence to obtain the first correlation sequence; the first PSS frequency domain data is the PSS frequency domain data after the interference is eliminated from the received time domain data; here , since the interference is eliminated from the received time domain data, the PSS frequency domain data after the interference elimination, that is, the first PSS frequency domain data is obtained. In this way, the interference is eliminated, and the detected cell in the first PSS frequency domain data has The number is reduced, thereby improving the cell search performance. Further, based on the preset first time offset value, respectively perform time offset compensation on the first transformation sequence obtained by discrete transformation of the first correlation sequence to obtain the first correlation compensation sequence; in this way, in the frequency domain PSS detection stage, adopt The method of discrete transformation performs time offset value compensation on the transformation sequence of the first PSS frequency domain data to obtain the first correlation compensation sequence, that is, the present application adopts the method of discrete transformation to make time offset assumptions, which reduces the amount of computation and the complexity of implementation, The efficiency of cell search is improved. Finally, based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data, the information of the target cell is determined; the first SSS frequency domain data is the SSS frequency domain data after interference is eliminated in the received time domain data; In this way, in the process of determining the information of the target cell based on the aforementioned first correlation compensation sequence, the first SSS frequency domain data and the preset first time offset value, both cell search performance and cell search efficiency are achieved.

Description of drawings

The drawings described herein are used to provide further understanding of the present application and constitute a part of the present application. The schematic embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation of the present application.

1 is a schematic diagram of an application scenario of an embodiment of the present application;

FIG. 2 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 3 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 4 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 5 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 6 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

Fig. 7 is a kind of implementation flow diagram of obtaining the candidate peak value of PSS by assuming the time offset by FFT provided by the embodiment of the present application;

FIG. 8 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 9 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 10 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 11 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

12 is a schematic diagram of the principle that a device searches for multiple co-frequency cells according to an embodiment of the present application;

FIG. 13 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 14 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 15 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application;

FIG. 16 is a schematic diagram of the composition and structure of a cell search apparatus according to an embodiment of the present application;

FIG. 17 is a schematic structural diagram of a device provided by an embodiment of the present application.

Detailed ways

The technical solutions of the present application will be specifically described in detail below with reference to the accompanying drawings. The following specific embodiments may be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

It should be noted that: in the examples of this application, "first", "second", etc. are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

In addition, the technical solutions described in the embodiments of the present application may be combined arbitrarily unless there is a conflict. In the description of the present application, "plurality" means two or more, unless otherwise expressly and specifically defined.

FIG. 1 is a schematic diagram of an application scenario of an embodiment of the present application.

As shown in FIG. 1 , the communication system 100 may include a first device 110 and a second device 120 . Here, the first device includes but is not limited to a terminal device and a chip, and the second device may be a network device. The second device 120 may communicate with the first device 110 through an air interface. Multi-service transmission is supported between the first device 110 and the second device 120 .

It should be understood that the embodiment of the present application only uses the communication system 100 for exemplary description, but the embodiment of the present application is not limited thereto. That is to say, the technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Long Term Evolution (Long Term Evolution, LTE) system, LTE Time Division Duplex (Time Division Duplex, TDD), Universal Mobile Communication System (Universal Mobile Telecommunication System (UMTS), Internet of Things (IoT) system, Narrow Band Internet of Things (NB-IoT) system, Enhanced Machine-Type Communications (eMTC) system, 5G A communication system (also called a New Radio (NR) communication system), or a future communication system (eg, 6G, 7G communication system), and the like.

In the communication system 100 shown in FIG. 1 , the second device 120 may be an access network device that communicates with the first device 110 . The access network device may provide communication coverage for a specific geographic area, and may communicate with the first device 110 located within the coverage area. The second device 120 in this embodiment of the present application may include an access network device and/or a core network device.

FIG. 1 exemplarily shows a base station and a first device. Optionally, the wireless communication system 100 may include multiple base station devices and the coverage of each base station may include other numbers of first devices. This application The embodiment does not limit this.

It should be noted that FIG. 1 only illustrates a system to which the present application applies in the form of an example. Of course, the methods shown in the embodiments of the present application may also be applied to other systems. Furthermore, the terms "system" and "network" are often used interchangeably herein. The term "and/or" in this article is only an association relationship to describe the associated objects, indicating that there can be three kinds of relationships, for example, A and/or B, it can mean that A exists alone, A and B exist at the same time, and A and B exist independently B these three cases. In addition, the character "/" in this document generally indicates that the related objects are an "or" relationship. It should also be understood that the "instruction" mentioned in the embodiments of this application may be a direct instruction, an indirect instruction, or an associated relationship. For example, if A indicates B, it can indicate that A directly indicates B, for example, B can be obtained through A; it can also indicate that A indicates B indirectly, such as A indicates C, and B can be obtained through C; it can also indicate that there is an association between A and B relation. It should also be understood that the "correspondence" mentioned in the embodiments of the present application may indicate that there is a direct or indirect corresponding relationship between the two, or may indicate that there is an associated relationship between the two, or may indicate and be indicated , configuration and configuration, etc. It should also be understood that the "predefinition", "protocol agreement", "predetermination" or "predefined rule" mentioned in the embodiments of the present application may be implemented by the device (for example, including the first device and the second device) It is implemented by pre-preserving corresponding codes, forms or other means that can be used to indicate relevant information in the system, and this application does not limit its specific implementation means. For example, predefined may refer to the definition in the protocol. It should also be understood that, in the embodiments of the present application, the “protocol” may refer to a standard protocol in the communication field, for example, may include the LTE protocol, the NR protocol, and related protocols applied in future communication systems, which are not limited in this application. .

然后进行辅同步信号(Secondary Synchronization Signal，SSS)序列检测，得到物理小区识别组(Physical Layer Cell Identity group)，进而得到小区的信息，其中，物理小区识别组也称NID1或

然而，在同频小区干扰的情况下，如何有效消除干扰小区的数据完成目标小区搜索。In the communication system, the terminal equipment needs to obtain time and frequency synchronization with the cell through the cell search phase, and search for the cell ID, so as to realize the communication with the network equipment. For example, performing correlation detection on the primary synchronization signal (Primary Synchronization Signal, PSS) sequence based on the received signal data in the cell search phase, to obtain at least one of the following: time offset, identity within the group, timing information, etc., Among them, the intra-group identifier is also called NID2 or

Then perform secondary synchronization signal (Secondary Synchronization Signal, SSS) sequence detection to obtain a physical cell identification group (Physical Layer Cell Identity group), and then obtain cell information, wherein the physical cell identification group is also called NID1 or NID1 or

However, in the case of intra-frequency cell interference, how to effectively eliminate the data of the interfering cell to complete the target cell search.

The technical solution of cell search based on cell signal interference cancellation in the related art is either based on time-domain interference cancellation. Specifically, after receiving the total time-domain data based on the target frequency band, the synchronization signal channel is estimated based on the time-domain data of the interfering cell. , and reconstruct the signal of the known interfering cell, and then cancel the interfering signal from the total received data. Then, the conventional target cell PSS and SSS detection is performed on the signal after interference cancellation to obtain cell information. Either based on frequency domain interference cancellation, specifically, based on the known interference cell signal PSS and SSS positions, take the data and do Fast Fourier Transform (FFT), and reconstruct the interference cell signal in the frequency domain, and then analyze the interference. The eliminated frequency domain signal is subjected to PSS and SSS frequency domain detection of the target cell, and finally cell information is obtained.

It should be noted that although the scheme for determining the target cell based on frequency domain interference cancellation is simpler to implement, and the amount of data and computation is relatively small, compared with the scheme for determining the target cell based on time domain interference cancellation, no matter whether it is determined based on time domain interference cancellation The solution of the target cell or the solution of determining the target cell based on interference cancellation in the frequency domain needs to reconstruct the interference signal, and has higher requirements on the processing of time offset.

In the related art, when performing PSS detection, the time offset processing process is: after receiving data other than the interfering cell, different time offset assumptions are made on the PSS frequency domain data in the data, and time offset assumptions are added to the data. The PSS frequency-domain data obtained are correlated in the frequency domain to obtain the correlation result after time offset compensation; wherein, the correlation result x ₁ (k) after time offset compensation can be realized by the following formula (1):

表示时偏值；k表示PSS序列第几个点，x(k)表示第k个PSS相关结果，N表示第一PSS频域数据的序列长度，L表示时偏值。where x ₁ (k) represents the correlation result after time offset compensation, xccor(k) represents the frequency domain correlation result between the first PSS frequency domain data and the local PSS sequence,

represents the time offset value; k represents the number of points in the PSS sequence, x(k) represents the kth PSS correlation result, N represents the sequence length of the first PSS frequency domain data, and L represents the time offset value.

Further, the correlation result after time offset compensation needs to be normalized and antenna combining operation, so the correlation result after time offset compensation x ₁ (k) is accumulated to obtain the accumulated result Y, as shown in the following formula (2),

Among them, M is the total number of time offset values.

Finally, based on the square of the accumulated result, the time offset used for time offset compensation for the SSS signal is estimated, and then the time offset compensation is performed on the SSS signal and frequency domain correlation processing is performed to determine the information of the target cell. However, in the process of time offset compensation for PSS frequency domain data, if there are multiple such as S time offset values L, S is an integer greater than or equal to 2, and S multiplications need to be performed according to the above formula (1). , according to the above formula (2), N×S square sums need to be performed; that is, the method for compensating the time offset value of PSS frequency domain data in the related art has the computational complexity of S multiplications and N×S times. sum of square. Obviously, this method at least has the problem of a large amount of computation, resulting in low cell search efficiency.

FIG. 2 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application. As shown in FIG. 2 , the method may be applied to a device, and the device may be a chip or a Terminal equipment. Here, the terminal equipment is used as the execution subject for description, and the method includes:

Step 201: Perform a cross-correlation operation on the first PSS frequency domain data and the local PSS sequence to obtain a first correlation sequence.

Wherein, the first PSS frequency domain data is PSS frequency domain data after interference is eliminated from the received time domain data.

In the embodiment of the present application, the time domain data is signal data of at least two cells in the same frequency band received within the search range after the terminal device resides in a serving cell. It should be noted that, after camping on a serving cell, the terminal device regards the serving cell as a known cell, and starts a neighbor cell search, so that the terminal device can reselection for the next serving cell, that is, the target cell, in the process of moving. Or switch to prepare.

Here, due to the limitation of spectrum resources and the requirement of high bandwidth of LTE, the communication system uses the same-frequency networking mode to improve the utilization rate of spectrum resources. Exemplarily, in a given coverage area, there are many cells using the same set of frequencies, and these cells are called co-frequency cells. Interference between cells on the same frequency is called interference on the same frequency. When searching for a cell, it is necessary to eliminate the data of the interfering cells on the same frequency.

In the case of a low signal-to-noise ratio, when there are multiple co-frequency cells within the search range of the terminal equipment, the serving cell (known cell) where the terminal equipment resides will interfere with the search for the signal of the target cell (neighboring cell). Affect the cell search and cause the search to fail; at this time, it is necessary to reconstruct and eliminate the signal of the known cell to reduce the influence of the interference signal, so as to achieve the purpose of searching for the target cell.

In the embodiment of the present application, the first PSS frequency domain data is PSS frequency domain data after interference is eliminated from the received time domain data. Exemplarily, after the terminal equipment resides in a serving cell, the serving cell is regarded as a known cell, and the PSS frequency domain data of the known cell is reconstructed according to the position and time information of the known cell, and further, the PSS frequency domain data of the known cell is reconstructed from the time domain data. The PSS frequency domain data of the reconstructed known cell is eliminated from the transformed hybrid PSS frequency domain data to obtain the first PSS frequency domain data.

In the embodiment of the present application, the local PSS sequence is a locally generated PSS sequence specified by the protocol, and each local PSS sequence corresponds to an intra-group identifier NID2 respectively. Optionally, the intra-group identifier NID2 may be 0, 1, or 2. It should be noted that the local PSS sequence is essentially formed by cyclic shift of the same sequence, and the local PSS sequence can be obtained in advance and stored in the terminal device.

Here, the cross-correlation operation refers to an operation that analyzes two or more correlated variable elements to measure the degree of correlation between two variable elements. In the embodiment of the present invention, a cross-correlation operation is performed on the two sequences, that is, an operation of calculating the degree of closeness between the two sequences.

Optionally, performing a cross-correlation operation on the first PSS frequency domain data and the local PSS sequence to obtain the first correlation sequence may include: performing a cross-correlation operation on the first PSS frequency domain data and each local PSS sequence in the multiple local PSS sequences respectively. A cross-correlation operation is performed between them to obtain a first correlation sequence corresponding to each local PSS sequence.

Optionally, performing a cross-correlation operation on the first PSS frequency domain data and the local PSS sequence to obtain a first correlation sequence, may also include: performing a frequency domain conjugate point product on the first PSS frequency domain data and the local PSS sequence to obtain The first correlation sequence.

Step 202: Based on the preset first time offset value, respectively perform time offset compensation on the first transformation sequence obtained by discrete transformation of the first correlation sequence to obtain a first correlation compensation sequence.

In the embodiment of the present application, the first time offset value is used to perform time offset compensation on the first transformation sequence, and the first transformation sequence is a sequence obtained by the discrete transformation of the first correlation sequence; the first time offset value is a pre-estimated other The value by which the position signal differs between a cell and a known cell for the terminal device.

Optionally, the first time offset value is less than or equal to half of the cyclic prefix in the time domain data. In this way, it is guaranteed that the complete first PSS frequency domain data and the complete first SSS frequency domain data can be obtained. It should be noted that the cyclic prefix (CyclicPrefix, CP) is formed by moving the signal at the end of the orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing, OFDM) symbol to the head. The purpose of the cyclic prefix is to ensure complete information. At the same time, the cyclic prefix can realize time pre-estimation and frequency synchronization. Therefore, in this solution, the cyclic prefix is used to estimate the time offset between the target cell and the current serving cell of the terminal equipment in advance, that is, the preset first time offset value.

Optionally, the preset number of first time offset values is related to the network standard of the serving cell where the terminal device resides, and serving cells of different network standards correspond to different numbers of first time offset values.

Optionally, the number of the first time offset values is related to the priority of the network standard of the cell where the terminal device resides; here, the number of the first time offset value is related to the priority of the network standard of the cell where the terminal device resides. proportional. Exemplarily, if the cell where the terminal device resides is an NR network cell, the number of the first time offset values belongs to the first range, and the first range may be [10, 15]; if the cell where the terminal device resides is LTE In the network cell, the number of the first time offset value belongs to the second range, and the second range can be [7, 10], and the priority of the network standard of the NR network is higher than the priority of the network standard of the LTE network; of course, if the terminal The cell where the device resides may also be another network cell, which is not specifically limited in this application.

It should be noted that, since the first correlation compensation sequence is obtained by performing time offset compensation on the first transformation sequence based on the preset first time offset value, the first transformation sequence is the sequence obtained by the discrete transformation of the first correlation sequence, And the first correlation sequence is the result of the cross-correlation operation between the first PSS frequency domain data and each local PSS sequence, so for the first time offset value, each first correlation compensation sequence corresponds to a unique local PSS sequence and a unique No. 1 PSS sequence. Temporary bias.

Optionally, the discrete transform may be a Fourier transform (Fourier Transform, FT).

Optionally, the discrete transform may also be a Fast Fourier Transform (Fast Fourier Transform, FFT).

Optionally, the discrete transform may also be a discrete Fourier transform (Discrete Fourier Transform, DFT). Exemplarily, the operation principle of discrete Fourier transform is as follows: formula (3):

Among them, X(k) represents the sequence after the DFT transformation, x(n) is the transformed sequence, N represents the length of the DFT transformation, n represents the sequence number of the sequence sample, and k is the independent variable of the spectrum.

Optionally, the first transformation sequence is obtained by discretely transforming the first correlation sequence, which can be completed by using the FPGA-based fast Fourier transform IP core in the terminal device, that is, using the FPGA-based fast Fourier transform FFT of the terminal device. The IP core completes the Fourier transform calculation of the first correlation sequence to obtain the first transform sequence. In this way, using the pre-designed FFT IP core, the implementation is simple, and the operation efficiency is greatly improved.

In an implementation scenario, taking the discrete transform to discrete Fourier transform as an example, after the first PSS frequency domain data and the local PSS sequence are cross-correlated to obtain the first correlation sequence xccor(n), the first correlation The sequence xccor(n) is subjected to discrete Fourier transform to obtain the first transformation sequence X ₂ (k); after that, based on the preset first time offset value, the first transformation sequence X ₂ (k) is respectively subjected to time offset compensation , the first correlation compensation sequence is obtained. Here, the first transformation sequence X ₂ (k) can be obtained by the following formula (4):

Wherein, X ₂ (k) represents the first transform sequence, and xccor(k) represents the frequency-domain correlation result between the first PSS frequency-domain data and the local PSS sequence.

Step 203: Determine the information of the target cell based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data.

Wherein, the first SSS frequency domain data is SSS frequency domain data after interference has been eliminated from the received time domain data.

In this embodiment of the present application, determining the information of the target cell at least includes determining the physical cell identifier (Physical Cell Identifier, PCI) and frame synchronization position of the target cell.

In the embodiment of the present application, the first SSS frequency-domain data is the SSS frequency-domain data after interference is eliminated from the received time-domain data. Exemplarily, after the terminal equipment resides in a serving cell, the serving cell is regarded as a known cell, and the SSS frequency domain data of the known cell is reconstructed according to the location and time information of the known cell; further, from the time domain data The reconstructed SSS frequency domain data of the known cell is eliminated from the transformed hybrid SSS frequency domain data to obtain first SSS frequency domain data.

Here, there is a fixed positional relationship between the PSS and the SSS of the primary and secondary synchronization signals corresponding to the communication mode, and the terminal device can determine the first SSS frequency domain through the frequency domain position of the first PSS frequency domain data and the positional relationship of the primary and secondary synchronization signals. The frequency domain location of the data. The communication modes include TDD mode and frequency division duplex FDD mode. Further, the fixed position relationship of the primary and secondary synchronization signals includes but is not limited to: in the FDD mode, the difference between the primary synchronization signal and the secondary synchronization signal is one OFDM symbol; in the TDD mode, the difference between the primary synchronization signal and the secondary synchronization signal is Three OFDM symbols.

In the embodiment of the present application, based on the preset first time offset value, the time offset compensation is performed on the first transformation sequence after the discrete transformation of the first correlation sequence, and the first correlation compensation sequence is obtained, based on the first correlation compensation sequence. The information of the target cell is determined by the correlation compensation sequence, a plurality of preset first time offset values and the first SSS frequency domain data.

In the embodiment of the present application, the cross-correlation operation is performed on the first PSS frequency domain data and the local PSS sequence to obtain the first correlation sequence; the first PSS frequency domain data is the PSS frequency domain data after the interference is eliminated from the received time domain data; here , since the interference is eliminated from the received time domain data, the PSS frequency domain data after the interference elimination, that is, the first PSS frequency domain data is obtained. In this way, the interference is eliminated, and the detected cell in the first PSS frequency domain data has The number is reduced, thereby improving the cell search performance. Further, based on the preset first time offset value, respectively perform time offset compensation on the first transformation sequence obtained by discrete transformation of the first correlation sequence to obtain the first correlation compensation sequence; in this way, in the frequency domain PSS detection stage, adopt The method of discrete transformation performs time offset value compensation on the transformation sequence of the first PSS frequency domain data to obtain the first correlation compensation sequence, that is, the present application adopts the method of discrete transformation to make time offset assumptions, which reduces the amount of computation and the complexity of implementation, The efficiency of cell search is improved. Finally, based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data, the information of the target cell is determined; the first SSS frequency domain data is the SSS frequency domain data after interference is eliminated in the received time domain data; In this way, in the process of determining the information of the target cell based on the aforementioned first correlation compensation sequence, the first SSS frequency domain data and the preset first time offset value, both cell search performance and cell search efficiency are achieved.

FIG. 3 is a schematic diagram of an implementation flowchart of an optional cell search method provided by an embodiment of the present application. As shown in FIG. 3 , the method may be applied to a device, and the device may be a chip or a Terminal equipment. Here, the terminal equipment is used as the execution subject for description, and the method includes:

Step 301: Perform a cross-correlation operation on the first PSS frequency domain data and the local PSS sequence to obtain a first correlation sequence.

Wherein, the first PSS frequency domain data is PSS frequency domain data after interference is eliminated from the received time domain data.

Step 302: Perform discrete transformation on the first correlation sequence to obtain a first transformed sequence.

Step 303: From the first transformation sequence, determine the first correlation compensation sequence corresponding to the offset of the first time offset value, so as to complete the time offset compensation.

Here, since there are multiple local PSS sequences, there are also multiple first transformation sequences that perform discrete transformation on the first correlation sequence. From each transformation sequence, determine each corresponding offset value of the first time offset The correlation compensation sequence is obtained, and then a plurality of correlation compensation sequences are obtained, so as to complete the time offset compensation. In this way, each sampling point in the first transformation sequence after discrete transformation is shifted by the first time offset value to obtain the first correlation compensation sequence. The discrete value of the corresponding position when the temporary offset value is used, so that the time for detecting the synchronization signal can be reduced, so that the target cell can be quickly searched, and the cell search efficiency can be further improved.

Here, taking discrete transformation into discrete Fourier transform as an example, after obtaining the first transformation sequence X ₂ (k), from each first transformation sequence X ₂ (k), determine the offset first time offset value L The first correlation compensation sequence corresponding to the time is obtained, and a plurality of first correlation compensation sequences are obtained to complete the time offset compensation.

Y1=X ₂ (kL)

Wherein, Y1 represents a plurality of first correlation compensation sequences, and L represents a first time offset value.

Step 304: Determine a second time offset value based on the first time offset value and the first correlation compensation sequence.

In this embodiment of the present application, the second time offset value may be used to perform time offset compensation on the second correlation sequence obtained after the cross-correlation operation is performed between the first SSS frequency domain data and the local SSS sequence; of course, the second time offset value may also be used The present application does not make a specific limitation on performing time offset compensation on the second correlation sequence that has undergone Fourier transform.

Step 305: Based on the second time offset value, perform time offset compensation on the second correlation sequence obtained by performing the cross-correlation operation between the first SSS frequency domain data and the local SSS sequence, to obtain a second correlation compensation sequence.

Wherein, the first SSS frequency domain data is SSS frequency domain data after interference has been eliminated from the received time domain data.

In the embodiment of the present application, the local SSS sequence is a locally generated SSS sequence specified by the protocol, and each local SSS sequence corresponds to a group ID identifier NID1 respectively. Optionally, in the LTE network, there are 168 group ID identifiers NID1 in total, that is, NID1 can be 0-167; in the NR network, there are 336 group ID identifiers NID1 in total, that is, NID1 can be 0-167. 335. Of course, in other networks, the total number of intra-group identifiers NID1 may be other values, which are not specifically limited in this application. Here, the local SSS sequence can be obtained in advance and stored in the terminal device.

Optionally, based on the second time offset value, performing time offset compensation on the second correlation sequence obtained by performing the cross-correlation operation between the first SSS frequency domain data and the local SSS sequence, to obtain a second correlation compensation sequence, which may include: Cross-correlation operation is performed between the SSS frequency domain data and the local SSS sequence to obtain a second correlation sequence; based on the second time offset value, time offset compensation is performed on the second correlation sequence to obtain a second correlation compensation sequence.

Optionally, based on the second time offset value, performing time offset compensation on the second correlation sequence obtained by performing the cross-correlation operation between the first SSS frequency domain data and the local SSS sequence, to obtain a second correlation compensation sequence, which may include: Perform cross-correlation operation on the SSS frequency domain data and the local SSS sequence to obtain a second correlation sequence; perform discrete transformation on the second correlation sequence to obtain a second transformed sequence; based on the second time offset value, perform time offset compensation on the second transformed sequence , the second correlation compensation sequence is obtained.

Optionally, performing a cross-correlation operation on the first SSS frequency domain data and the local SSS sequence to obtain a second correlation sequence, may also include: performing a frequency domain conjugate point product on the first SSS frequency domain data and the local SSS sequence to obtain Second correlation sequence.

Step 306: Determine the information of the target cell based on the first correlation compensation sequence and the second correlation compensation sequence.

In the embodiment of the present application, the first correlation sequence of PSS is processed by discrete transformation to obtain the first transformation sequence, and then the time offset compensation is performed on the first transformation sequence based on the first time offset value to obtain the first correlation compensation sequence; The second time offset value compensates the second transformation sequence of the SSS to obtain a second correlation compensation sequence. In this way, the discrete transformation is effectively used to make a time offset compensation assumption for the first transformation sequence of the PSS. Based on obtaining each first time offset value The value of the corresponding position in the first correlation compensation sequence and the second time offset value are used to compensate the second transformation sequence of the SSS to obtain a sequence, and the information of the target cell is determined, which greatly reduces the amount of data operation and the complexity of implementation, thereby The search time is reduced and the search efficiency of the cell is improved.

In some embodiments, in the case of completing the time offset compensation for the first transformation sequence based on the preset first time offset value to obtain the first correlation compensation sequence, step 304 is based on the first time offset value and the first correlation compensation sequence, the process of determining the second time offset value is further explained in conjunction with Fig. 4,

Step 401: Determine a first candidate peak based on the first time offset value and the first correlation compensation sequence.

In this embodiment of the present application, the first candidate peak corresponds to a first time offset value and a local PSS sequence, and the first candidate peak may be a peak that satisfies the peak condition from the first correlation compensation sequence; the first candidate peak is used for estimation based on The time offset value of the time offset compensation for the sequence obtained from the SSS frequency domain data.

Step 402: Perform a remainder operation on the first candidate peak value and the length of the first PSS frequency domain data to obtain a second time offset value.

In this embodiment of the present application, the length of the first PSS frequency domain data is the number of points for discrete transformation.

Here, when the first candidate peak value is determined based on the first time offset value and the first correlation sequence, a remainder operation is performed on the first candidate peak value and the length of the first PSS frequency domain data to obtain the second time offset value. Among them, the second time offset value can be realized by the following formula (5):

Y3=mod(Y2, N) (5)

Wherein, Y3 represents the second time offset value, Y2 represents the first candidate peak value, N represents the length of the first PSS frequency domain data, and mod represents a remainder function.

Optionally, performing a remainder operation on the length of the first candidate peak and the first PSS frequency domain data to obtain a second time offset value, which may include: the first candidate peak includes: a plurality of first candidate peaks, and each A remainder operation is performed between a candidate peak value and the length of the first PSS frequency domain data to obtain at least one second time offset value.

It can be seen from the above that in the case of determining the first candidate peak corresponding to the first correlation compensation sequence, by performing a remainder operation on the first candidate peak and the PSS frequency domain data, not only can the obtained peak value obtained based on the first SSS frequency domain data be obtained. The time offset compensation value of the sequence may also determine the position of the first SSS frequency domain data based on the position of the first candidate peak. In this way, the position of the SSS data can be quickly located, so as to improve the search efficiency.

In some embodiments, in the case of completing the time offset compensation for the first transformation sequence based on the preset first time offset value to obtain the first correlation compensation sequence, step 401 is based on the first time offset value and the first correlation compensation sequence, the process of determining the first candidate peak is further described in conjunction with FIG. 5,

Step 501, the first time offset value includes: W first time offset values, each first time offset value corresponds to N1 first sub-correlation compensation sequences, and the first correlation compensation sequence includes W first time offset values corresponding to respectively. The N1 first sub-correlation compensation sequences of , for each first time offset value, based on the N1 first sub-correlation compensation sequences, N1 first peaks are determined.

Wherein, W is an integer greater than or equal to 1, and N1 is an integer greater than or equal to 1.

Here, N1 is the total number of all local PSS sequences.

In the embodiment of the present application, for each first time offset value in the W first time offset values, based on the first correlation compensation sequence including N1 first sub-correlation compensation sequences corresponding to the W first time offset values respectively, Determine N1 first peaks.

Step 502 , for the W first time offset values, from W×N1 first peaks, determine U first candidate peaks that are greater than or equal to a first preset peak threshold.

Wherein, U is an integer greater than or equal to 1 and less than or equal to W×N1.

In this embodiment of the present application, the first preset peak threshold may be a preset peak value, and the first preset peak threshold may also be a peak value dynamically adjusted according to the current scene, which is not specifically limited in this application.

In this embodiment of the present application, for W first time offset values, from W×N1 first peaks, U first candidate peaks that are greater than or equal to the first preset peak threshold are determined, so that according to the first candidate peaks, SSS correlation detection is performed in order to determine the information of the target cell.

It can be seen from the above that when there are multiple first time offset values, in the first correlation compensation sequence obtained by discrete transformation, each first time offset value corresponds to multiple first sub-correlations in the first correlation compensation sequence. Compensation sequence, each first sub-correlation compensation sequence will have a peak value, so each first time offset value will correspond to multiple peaks, from all the peaks corresponding to all the first time offset values, filter out the peaks that meet the conditions As the first candidate peak, in this way, not only the position of the first SSS frequency domain data is determined based on the position of the first candidate peak, but also the time offset compensation value for the sequence obtained based on the first SSS frequency domain data can be obtained, so as to adjust the time offset The compensated SSS-related data is detected to determine the information of the target cell.

In some embodiments, based on the preset W first time offset values, the time offset compensation is performed on the first transformation sequence, to obtain N1 first sub-correlation compensation sequences corresponding to the W first time offset values respectively. In the case of the first correlation compensation sequence, step 501 for each first time offset value, based on the N1 first sub-correlation compensation sequences, the process of determining N1 first peaks is further described with reference to FIG. 6 ,

Step 601: For each first time offset value, based on N1 first sub-correlation compensation sequences, obtain energy distribution information corresponding to each first sub-correlation compensation sequence.

In this embodiment of the present application, the energy distribution information includes but is not limited to a plurality of discrete values corresponding to each first sub-correlation compensation sequence. In some embodiments, for each first time offset value, based on the N1 first sub-correlation compensation sequences, a plurality of discrete values corresponding to each first sub-correlation compensation sequence may be normalized to obtain an energy distribution information, of course, in other embodiments of the present application, the energy distribution information may also be obtained in other ways, which is not specifically limited in the present application.

Step 602: Based on the energy distribution information corresponding to each first sub-correlation compensation sequence, determine the first peak value corresponding to each first sub-correlation compensation sequence, thereby obtaining N1 first peak values corresponding to the N1 first sub-correlation compensation sequences .

In the embodiment of the present application, first, for each first time offset value L, based on N1 first sub-correlation compensation sequences, each first sub-correlation compensation sequence, that is, X ₂ (kL), is obtained. Since the value range of k is [0, N-1], so when k takes different values, there will be a corresponding discrete value. When k takes all values, multiple discrete values are obtained, and then the energy distribution corresponding to each first sub-correlation compensation sequence is obtained. Secondly, determine the maximum peak value as the first peak from the energy distribution information corresponding to each first sub-correlation compensation sequence, so as to obtain N1 first peaks corresponding to the N1 first sub-correlation compensation sequences, and then from the N1 first sub-correlation compensation sequences The candidate peaks are screened out from a peak, the information of the target cell is determined, and the search efficiency of the target cell is improved.

In some embodiments, for each first time offset value, based on N1 first sub-correlation compensation sequences, a plurality of discrete values corresponding to each first sub-correlation compensation sequence are normalized to obtain energy distribution information , which can be achieved by the following process:

For each first time offset value, based on N1 first sub-correlation compensation sequences, perform normalization processing on a plurality of discrete values corresponding to each first sub-correlation compensation sequence to obtain the corresponding multiple normalized values of .

The energy distribution information includes a plurality of normalized values corresponding to each first sub-correlation compensation sequence.

In the embodiment of the present application, first, for each first time offset value L, based on N1 first sub-correlation compensation sequences, each first sub-correlation compensation sequence, namely X ₂ (kL), is obtained. Since the value range of k It is [0, N-1], so when k takes different values, it will correspond to a discrete value. When k takes all values, multiple discrete values are obtained. Second, obtain the squares of all discrete values and sum them up to obtain the sum of squares, and then take the quadratic root of the sum of squares to obtain the PSS energy, square each of the multiple discrete values, and calculate the squared value of each squared value. The discrete value is divided by the PSS energy to obtain a plurality of normalized values corresponding to each first sub-correlation compensation sequence, and then energy distribution information corresponding to each first sub-correlation compensation sequence is obtained. Specifically, the multiple normalized values corresponding to each first sub-correlation compensation sequence can be obtained by the following formula (6):

Y4=|Y1| ² /S=|X ₂ (kL)| ² /S (6)

Wherein, Y4 represents a plurality of normalized values corresponding to each first sub-correlation compensation sequence, Y1 represents the first sub-correlation compensation sequence, and S represents the PSS energy.

Further, the terminal device determines the first peak value with the largest value from the plurality of normalized values corresponding to each first sub-correlation compensation sequence, thereby obtaining N1 first peak values corresponding to the N1 first sub-correlation compensation sequences. . In this way, through the normalization processing method, multiple normalized values are obtained, and peaks can be quickly obtained from the multiple normalized values, so as to obtain N1 first peaks, and then select candidate peaks from the N1 first peaks , and then determine the information of the target cell and improve the search efficiency of the target cell.

In an achievable application scenario, referring to FIG. 7 , FIG. 7 shows a schematic flowchart of obtaining a first candidate peak value by assuming a time offset through FFT provided by an embodiment of the present application. After obtaining the first PSS frequency domain data, perform frequency domain correlation descrambling on the first PSS frequency domain data, that is, cross-correlation operation, and according to the preset first time offset value, perform frequency domain correlation descrambling on the first PSS frequency domain correlation descrambling The PSS frequency domain data is subjected to the fast Fourier transform FFT time-offset assumption to obtain the first correlation compensation sequence; in addition, the PSS energy of the first PSS frequency domain data is calculated, and normalized based on the calculated PSS energy and the first correlation compensation sequence Here, the normalization process is also called the antenna combination normalization process. Based on the normalized first correlation compensation sequence, the candidate peak corresponding to the first correlation compensation sequence is determined, so as to determine the information of the target cell according to the candidate peak, and then The search efficiency of the target cell is improved.

In some embodiments, in the case of determining the second time offset value, step 305 performs time offset on the second correlation sequence obtained by performing the cross-correlation operation between the first SSS frequency domain data and the local SSS sequence based on the second time offset value compensation, the process of obtaining the second correlation compensation sequence is further described in conjunction with FIG. 8 ,

Step 801: Perform a cross-correlation operation on the first SSS frequency domain data and the local SSS sequence to obtain a second correlation sequence.

Step 802: Perform discrete transformation on the second correlation sequence to obtain a second transformed sequence.

Step 803: From the second transformation sequence, determine a second correlation compensation sequence corresponding to the offset of the second time offset value, so as to complete the time offset compensation.

In the embodiment of the present application, the local SSS sequence includes a plurality of local SSS sequences, and a cross-correlation operation is performed on the first SSS frequency domain data and each local SSS sequence in the plurality of local SSS sequences to obtain a plurality of second correlation sequences; based on A plurality of second correlation sequences, discretely transforming each second correlation sequence to obtain a plurality of second transformation sequences; based on the plurality of second transformation sequences, from each second transformation sequence, determine the offset second time offset The second correlation compensation sequence corresponding to the time value is obtained, and a plurality of second correlation compensation sequences are obtained, so as to complete the time offset compensation. In this way, each sampling point in the second transformation sequence after discrete transformation is offset by the second time offset value to obtain the second correlation compensation sequence. The two-time offset value is a discrete value of the corresponding position, so that the time for detecting the synchronization signal can be reduced, so as to quickly detect the target cell and further improve the search efficiency of the cell.

In some embodiments, in the case of obtaining the first correlation compensation sequence and the second correlation compensation sequence, step 306 is based on the first correlation compensation sequence and the second correlation compensation sequence, and the process of determining the information of the target cell is further combined with FIG. 9 . to explain,

Step 901: Determine a second candidate peak based on the second time offset value and the second correlation compensation sequence.

Wherein, the second candidate peak corresponds to a second time offset value and a local SSS sequence.

In the embodiment of the present application, the second candidate peak corresponds to a second time offset value and a local SSS sequence, that is, the group ID NID1 corresponding to the second candidate peak is determined, and the existence of the second candidate peak and the first candidate peak is associated .

Step 902: Determine the information of the target cell based on the first candidate peak value and the second candidate peak value corresponding to the first correlation compensation sequence.

The first candidate peak corresponds to a first time offset value and a local PSS sequence.

In the embodiment of the present application, the first candidate peak corresponds to a first time offset value and a local PSS sequence, that is, the intra-group identifier NID2 corresponding to the first candidate peak is determined.

In the embodiment of the present application, based on the group ID identifier NID1 corresponding to the second candidate peak value and the intra-group identifier NID2 corresponding to the first candidate peak value corresponding to the second candidate peak value, the physical cell identifier PCI of the target cell is determined, and the target cell is then obtained. community information.

Here, determining the physical cell identity PCI of the target cell can be obtained by the following formula (7):

PCI=3×NID1+NID2 (7)

Wherein, PCI represents the physical cell identifier of the target cell, NID1 represents the group ID corresponding to the second candidate peak, and NID2 represents the corresponding intra-group identifier of the first candidate peak corresponding to the second candidate peak.

It can be seen from the above that when the first candidate peak corresponding to the PSS data and the second candidate peak corresponding to the SSS data are determined, based on the position of the second candidate peak, and the obtained second candidate peak corresponding to the first candidate peak position, and determine the information of the target cell, so as to ensure that the terminal equipment can quickly reselect or switch to the target cell in the process of moving.

In some embodiments, in the case of obtaining the second time offset value and the second correlation compensation sequence, step 901 is based on the second time offset value and the second correlation compensation sequence, and the process of determining the second candidate peak value is further combined with FIG. 10 . to explain,

Step 1001, the second time offset value includes: P second time offset values, each second time offset value corresponds to N2 second sub-correlation compensation sequences, and the second correlation compensation sequence includes P second time offset values corresponding to respectively. The N2 second sub-correlation compensation sequences are determined, for each second time offset value, based on the N2 second sub-correlation compensation sequences, N2 second peaks are determined.

Wherein, P is an integer greater than or equal to 1 and less than or equal to W; N2 is an integer greater than or equal to 1.

Here, N2 is the total number of all local SSS sequences.

Step 1002 , for the P second time offset values, from P×N2 second peaks, determine Q second candidate peaks that are greater than or equal to a second preset peak threshold.

Wherein, Q is an integer greater than or equal to 1 and less than or equal to P×N2.

In this embodiment of the present application, the second preset peak threshold may be a preset peak value, and the second preset peak threshold may also be a peak value dynamically adjusted according to the current scene, such as dynamically set to obtain the largest candidate peak The second preset peak threshold value of , which is not specifically limited in this application. It should be noted that the first preset peak threshold and the second preset peak threshold may be the same, and the first preset peak threshold and the second preset peak threshold may also be different, which are not specifically limited in this application.

In the embodiment of the present application, first, for each second time offset value in the P second time offset values, the second correlation compensation sequence includes N2 second sub-correlation compensations corresponding to the P second time offset values respectively sequence to determine N2 second peaks. Secondly, for the P second time offset values, from the P×N2 second peaks, determine Q second candidate peaks that are greater than or equal to the second preset peak threshold, so as to determine the target cell’s information.

It can be seen from the above that when there are multiple second time offset values, in the second correlation compensation sequence obtained by discrete transformation, each second time offset value corresponds to multiple second sub-correlations in the second correlation compensation sequence. Compensation sequence, each second sub-correlation compensation sequence will have a peak, so each second time offset value will correspond to multiple peaks, from all the peaks corresponding to all second time offset values, filter out the peaks that meet the conditions As the second candidate peak, the information of the target cell can be determined based on the position of the second candidate peak and the position of the first candidate peak corresponding to the obtained second candidate peak, thus ensuring that the terminal equipment is in the process of moving , you can quickly reselect or switch to the target cell.

FIG. 11 is a schematic flowchart of an implementation of an optional cell search method provided by an embodiment of the present application. As shown in FIG. 11 , the method may be applied to a device, and the device may be a chip or a Terminal equipment. Here, the terminal equipment is used as the execution subject for description, and the method includes:

Step 1101: Perform data transformation on the received time domain data of multiple cells to obtain second PSS frequency domain data and second SSS frequency domain data.

In this embodiment of the present application, the time-domain data is composed of signals of multiple co-frequency cells plus noise. For example, the noise may be Additive White Gaussian Noise (AWGN). Referring to FIG. 12, FIG. 12 shows a schematic diagram of the principle that the device searches for multiple cells with the same frequency; when there are multiple cells with the same frequency in the search range of the terminal device, the received time domain data is the signal from the multiple cells. Add noise.

Optionally, performing data transformation on the received time domain data of multiple cells may include: performing frequency domain transformation on the received time domain data of multiple cells.

Optionally, performing data transformation on the received time-domain data of multiple cells may include: performing fast Fourier transform on the received time-domain data of multiple cells.

Here, after receiving the time-domain data of multiple same-frequency cells, the terminal performs fast Fourier transform on the time-domain data to obtain frequency-domain data, where the frequency-domain data includes the second PSS frequency-domain data and the second SSS frequency-domain data data.

It should be noted that the received signal data can be modeled in the frequency domain space, that is, Y=∑ _i H _i ×D _i +N; wherein, Y represents the signal data received through the channel, and H _i represents the i-th The channel frequency response of the channel, D _i represents the signal data transmitted on the ith channel. The received signal data is composed of multiple cell signals plus noise. Interfering cell elimination mainly refers to eliminating the interfering cell signals in the same frequency band and the signal position difference does not exceed the cyclic prefix range. The basic principle is to estimate and reconstruct the signals of each cell at the UE receiving end. Then, these interferences are sequentially subtracted from the received signal, and the finally obtained signal is subjected to cell detection to obtain the information of the target cell.

Step 1102: Eliminate the PSS frequency domain data reconstructed for the known cells of the same frequency in the second PSS frequency domain data to obtain the first PSS frequency domain data; Knowing the reconstructed SSS frequency domain data of the cell, the first SSS frequency domain data is obtained.

In the embodiment of the present application, the known cell may be the serving cell where the terminal device currently resides, and the known cell may also be a neighboring cell of the serving cell where the terminal device resides. or information of the first target cell determined after multiple cell detections. Here, the known cell can also be called an interfering cell, and the known cell can also be any cell except the first target cell. No specific restrictions are imposed.

In this embodiment of the present application, there may be one known cell, or there may be multiple known cells; in the case of multiple known cells, in the second PSS frequency domain data, multiple known cells for the same frequency are eliminated. The PSS frequency domain data reconstructed by the cell obtains the first PSS frequency domain data; and in the second SSS frequency domain data, the reconstructed SSS frequency domain data for a plurality of known cells of the same frequency are eliminated to obtain the first SSS frequency domain data.

In the embodiment of the present application, in the case of performing data transformation on the received time domain data of multiple cells to obtain the second PSS frequency domain data and the second SSS frequency domain data, the reconstructed PSS of the known cells of the same frequency is obtained. frequency domain data and reconstructed SSS frequency domain data, and eliminate the reconstructed PSS frequency domain data of the known cell from the second PSS frequency domain data to obtain the first PSS frequency domain data; eliminate from the second SSS frequency domain data Knowing the reconstructed SSS frequency domain data of the cell, the first SSS frequency domain data is obtained.

In some embodiments, in step 1102, in eliminating the second PSS frequency domain data, the PSS frequency domain data reconstructed for a known cell of the same frequency is obtained to obtain the first PSS frequency domain data; and in eliminating the second SSS frequency domain data, For the reconstructed SSS frequency domain data of a known cell of the same frequency, the obtained first SSS frequency domain data is further described in conjunction with FIG. 13 ,

Step 1301: Perform a least squares parameter estimation on the second SSS frequency domain data to obtain a first channel frequency response of a known cell.

In this embodiment of the present application, the first channel frequency response of the known cell may be directly obtained by estimating the Least Square Method (LS) parameter of the second SSS frequency domain data. Of course, the first channel frequency response of the known cell The channel frequency response may be directly obtained after LS parameter estimation is performed on the second PSS frequency domain data, which is not specifically limited in this application.

In other embodiments of the present application, the first channel frequency response of the known cell may also be obtained by performing LS parameter estimation on the second SSS frequency domain data to obtain the second channel frequency response, and filtering the second channel frequency response. Of course, the first channel frequency response of the known cell may also be obtained by performing LS parameter estimation on the second PSS frequency domain data to obtain the second channel frequency response, and filtering the second channel frequency response. In this regard, this application does not make any specific limitation.

Here, the first channel frequency response of the known cell is obtained by estimating the LS parameter of the second SSS frequency domain data as an example for illustration, and the second SSS frequency domain data and the local SSS sequence corresponding to the known cell are subjected to a dot division operation. , to get the first channel frequency response.

In some embodiments, step 1301 obtains the first channel frequency response of the known cell based on least squares parameter estimation on the second SSS frequency domain data.

Step 1401: Perform a least squares parameter estimation on the second SSS frequency domain data to obtain the second channel frequency response of the known cell.

Step 1402: Filter the frequency response of the second channel by using the minimum mean square error to obtain the frequency response of the first channel.

In the embodiment of the present application, in the case of performing least squares parameter estimation on the second SSS frequency domain data to obtain the second channel frequency response of the known cell, the minimum mean square error (Minimum Mean Square Error, MMSE) is used to determine the The second channel frequency response is filtered to obtain the first channel frequency response. In this way, by performing the filtering operation on the channel frequency response, the accuracy of the channel frequency response is improved, thereby improving the accuracy of the frequency reconstruction data of the known cell based on the first channel frequency response.

Step 1302: Reconstruct the local PSS sequence of the known cell by using the first channel frequency response to obtain PSS frequency domain reconstruction data of the known cell.

Step 1303: Eliminate PSS frequency domain reconstruction data in the second PSS frequency domain data to obtain first PSS frequency domain data.

Step 1304: Reconstruct the local SSS sequence of the known cell by using the first channel frequency response to obtain the SSS frequency domain reconstruction data of the known cell.

Step 1305: Eliminate the SSS frequency domain reconstruction data in the second SSS frequency domain data to obtain the first SSS frequency domain data.

In the embodiment of the present application, first, the terminal device receives time domain data, and performs fast Fourier transform on the received time domain data to obtain second PSS frequency domain data and second SSS frequency domain data; secondly, based on the second PSS frequency domain data The frequency domain data and the second SSS frequency domain data, after determining that the current cell where the terminal equipment resides is a known cell, determine the local PSS sequence and local SSS sequence corresponding to the known cell according to the location and time information of the known cell. Then, perform point division operation on the second SSS frequency domain data and the local SSS sequence corresponding to the known cell, that is, perform channel estimation on the known cell, so as to obtain the first channel frequency response of the known cell; The channel frequency response reconstructs the local PSS sequence of the known cell to obtain the PSS frequency domain reconstruction data of the known cell, and reconstructs the local SSS sequence of the known cell through the first channel frequency response to obtain the SSS frequency domain reconstruction data; finally, eliminate the PSS frequency domain reconstruction data of the known cell in the second PSS frequency domain data, obtain the first PSS frequency domain data, and eliminate the SSS frequency domain of the known cell in the second SSS frequency domain data domain reconstruction data to obtain the first SSS frequency domain data. In this way, by eliminating the frequency domain data of a known cell, such as the current cell or the target cell where the terminal device is located, and detecting the frequency domain data of other cells except the known cell, the complexity of PSS interference elimination is effectively reduced, and the PSS is improved. The efficiency of interference cancellation, thus providing convenience for the reselection and handover of terminal equipment.

It should be noted that, in the neighbor cell search process, it is assumed that there is no frequency offset between the neighbor cell and the serving cell, so it can be considered that the frequency domain estimation value of the PSS channel is equal to the frequency domain estimation value of the SSS channel. In this way, the calculation amount of PSS channel estimation can be saved, and there is no impact on performance.

Step 1103: Perform a cross-correlation operation on the first PSS frequency domain data and the local PSS sequence to obtain a first correlation sequence.

Step 1104: Based on the preset first time offset value, respectively perform time offset compensation on the first transformation sequence obtained by discrete transformation of the first correlation sequence to obtain a first correlation compensation sequence.

Step 1105: Determine the information of the target cell based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data.

It can be seen from the above that the position of the known cell is determined, and the reconstructed frequency domain data of the known cell is eliminated from the frequency domain data transformed from the total received time domain data to obtain the frequency domain data after interference cancellation. In this way, the interference of the same-frequency cell is eliminated, and the interference of the known cell can no longer be detected, so that the cell with the same frequency as the known cell and the power is weaker than the known cell can be detected. The accuracy of intra-frequency cell search also improves the detection performance of intra-frequency cells.

In some embodiments, after step 1105 determines the information of the target cell based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data, the following steps may be further performed:

Step 1106: In the case where the first PSS frequency domain data is the received time domain data after eliminating the interference of the known cell, update the first PSS frequency domain data and the first PSS frequency domain data with the target cell as the known cell. SSS frequency domain data, and based on the updated first PSS frequency domain data and the updated first SSS frequency domain data, determine the information of the next target cell until a preset stop condition is reached.

In this embodiment of the present application, the preset stop condition may be that the number of rounds that can be cycled is set according to the capability information of the terminal device; the preset stop condition may also be that the terminal device cannot detect PSS frequency domain data and/or SSS data.

In the embodiment of the present application, the first PSS frequency domain data of the terminal device is the received time domain data after eliminating the interference of the known cell, and the first SSS frequency domain data is the received time domain data. In the case of the interfered SSS frequency domain data of the cell, first, based on the first PSS frequency domain data and the first SSS frequency domain data, determine the information of the target cell; secondly, use the target cell as a known cell, and update the first PSS The frequency domain data and the first SSS frequency domain data, and based on the updated first PSS frequency domain data and the updated first SSS frequency domain data, determine the information of the next target cell until a preset stop condition is reached.

Here, taking the target cell as a known cell, the first PSS frequency domain data and the first SSS frequency domain data are updated, and based on the updated first PSS frequency domain data and the updated first SSS frequency domain data, the next The information of the target cell, until the preset stop condition is reached, can be achieved through the following process:

According to the location and time information of the target cell (known cell), determine the local PSS sequence and local SSS sequence corresponding to the target cell; then, perform point division operation on the first SSS frequency domain data and the local SSS sequence corresponding to the target cell, that is Channel estimation is performed on the target cell to obtain a third channel frequency response of the target cell; further, the local PSS sequence of the target cell is reconstructed through the third channel frequency response to obtain PSS frequency domain reconstruction data of the target cell, and the The third channel frequency response reconstructs the local SSS sequence of the target cell to obtain the SSS frequency domain reconstruction data of the target cell; finally, eliminates the PSS frequency domain reconstruction data of the target cell in the first PSS frequency domain data to obtain the third PSS frequency domain data (that is, update the first PSS frequency domain data), remove the SSS frequency domain reconstruction data of the target cell in the first SSS frequency domain data, and obtain the third SSS frequency domain data (that is, update the first SSS frequency domain data) . Further, a cross-correlation operation is performed on the third PSS frequency domain data and the local PSS sequence corresponding to the target cell to obtain a third correlation sequence; Time offset compensation is performed on the third transformation sequence to obtain a third correlation compensation sequence; based on the third correlation compensation sequence, the third time offset value and the third SSS frequency domain data, the information of the next target cell is determined, and so on, until the preset value is reached. The set number of cycles, or if the detection of PSS frequency domain data and/or SSS data fails, the search for the next target cell is stopped. In this way, information of multiple target cells is obtained through multiple detections.

As can be seen from the above, each time the information of a target cell is determined, the target cell can be regarded as a known cell, and the PSS frequency domain data reconstructed by the known cell can be eliminated from the first PSS frequency domain data to obtain the third PSS frequency domain data, Eliminate the reconstructed SSS frequency domain data of the known cell from the first SSS frequency domain data to obtain third SSS frequency domain data; further, perform PSS detection on the third PSS frequency domain data after interference cancellation, and perform the interference cancellation SSS detection is performed on the third SSS frequency domain data after that; the next target cell information is obtained, and so on, until the detection times reach the preset number of cycles, or the detection of PSS frequency domain data and/or SSS data fails, then stop searching for the target In this way, the interference of co-frequency cells is eliminated, and the interference of known cells can no longer be detected, so that multiple co-frequency cells can be searched, the accuracy of co-frequency cell search is improved, and the detection of co-frequency cells is also improved. performance; at the same time, it also ensures that the terminal equipment can quickly reselection or switch to the target cell in the process of moving.

FIG. 15 is a schematic flowchart of an implementation of an optional cell search method provided by an embodiment of the present application. As shown in FIG. 15 , the method may be applied to a device, and the device may be a chip or a Terminal equipment. Here, the terminal equipment is used as the execution subject for description, and the method includes:

Step 1501: Receive time domain data of multiple cells.

Step 1502: Perform fast Fourier transform on the time domain data to obtain second PSS frequency domain data and second SSS frequency domain data of multiple cells.

In this embodiment of the present application, the second PSS frequency domain data includes PSS frequency domain data and noise data of multiple cells. The second SSS frequency domain data includes SSS frequency domain data and noise data of a plurality of cells.

Step 1503: Obtain the local SSS sequence of the known cell.

Wherein, the plurality of cells include known cells.

In this embodiment of the present application, the known cell may be one or multiple, the known cell may be the serving cell where the terminal device currently resides, and the known cell may also be a neighboring cell of the serving cell where the terminal device resides Of course, the known cell may also be the information of the first target cell determined after one or more cell searches, and the known cell may also be any cell for which the information of the cell has been determined by other means.

Step 1504: Based on the local SSS sequence of the known cell, perform LS parameter estimation on the second SSS frequency domain data to obtain the second channel frequency response H of the known cell.

In the embodiment of the present application, the terminal device performs LS parameter estimation on the second SSS frequency domain data based on the local SSS sequence of the known cell, and obtains the second channel frequency response H of the known cell. It can be understood that the second SSS frequency The domain data is divided by the local SSS sequence of the known cell to obtain the second channel frequency response H of the known cell.

Step 1505: Filter the second channel frequency response by using the minimum mean square error to obtain the first channel frequency response H' of the known cell.

Step 1506: Reconstruct the local PSS sequence of the known cell through the first channel frequency response to obtain PSS frequency domain reconstruction data of the known cell, and reconstruct the local SSS sequence of the known cell through the first channel frequency response , obtain the SSS frequency domain reconstruction data of the known cell.

Step 1507: Update the second PSS frequency domain data based on the PSS frequency domain reconstruction data of the known cell, and update the second SSS frequency domain data based on the SSS frequency domain reconstruction data of the known cell.

In the embodiment of the present application, the PSS frequency domain reconstruction data of the known cell in the second PSS frequency domain data is eliminated, so as to realize the update of the second PSS frequency domain data; the known cell in the second SSS frequency domain data is eliminated The SSS frequency domain reconstruction data of the second SSS is implemented to update the second SSS frequency domain data.

Step 1508: Determine whether there are other known cells, if yes, go back to Step 1503; if not, go to Step 1509.

In this embodiment of the present application, if there are multiple known cells, and if it is determined that there are other known cells, steps 1503 to 1508 may be repeatedly executed to eliminate the signal of the next known cell until the elimination is complete. Signals from all known cells.

It should be noted that when the PSS frequency domain reconstruction data of all known cells has been eliminated from the second PSS frequency domain data, the obtained updated second PSS frequency domain data is the above-mentioned first PSS frequency domain data. Similarly, when the SSS frequency domain reconstruction data of all known cells has been eliminated from the second SSS frequency domain data, the obtained updated second SSS frequency domain data is the above-mentioned first SSS frequency domain data.

Step 1509: Obtain a preset first time offset value.

Step 1510: Based on the first time offset value, perform correlation compensation on and detect the updated second PSS frequency domain data, so as to obtain a second time offset value for performing correlation compensation on the updated second SSS frequency domain data.

Step 1511: Perform correlation compensation and detection on the updated second SSS frequency domain data based on the second time offset value.

Step 1512: Determine the information of the target cell.

Step 1513: Determine whether the preset stop condition is reached, if not, take the target cell as a known cell, and return to step 1503, and then determine the information of the next target cell; if so, the search ends.

In this embodiment of the present application, the preset stop condition may be that the number of rounds that can be cycled is set according to the capability information of the terminal device; the preset stop condition may also be that the terminal device cannot detect PSS frequency domain data and/or SSS data.

It can be seen from the above that since the frequency domain data of the known cell is eliminated in the received data, the second PSS frequency domain data and the second SSS frequency domain data after the interference of the known cell is eliminated, and the second PSS frequency domain data is obtained. The number of detected cells is reduced, thereby improving the search performance of the cells; further, in the frequency domain PSS detection stage, discrete transformation is used to analyze the updated second PSS frequency domain data (that is, the first PSS frequency domain data). The transformation sequence performs time offset compensation to obtain a relevant compensation sequence, and then determines the target cell based on the relevant compensation sequence, the updated second SSS frequency domain data (first SSS frequency domain data) and the preset first time offset value further, in the case where the preset stop condition is not reached, the target cell, as a known cell, continues to update the second PSS frequency domain data and the second SSS frequency domain data, and based on the updated second PSS frequency domain data and the updated second SSS frequency domain data to determine the information of the next target cell until the preset stop condition is reached. In this way, the computation amount and implementation complexity are greatly reduced, the efficiency of cell search is improved, and in the process of determining the information of the target cell, the dual consideration of cell search performance and cell search efficiency is achieved.

Based on the foregoing embodiments, the embodiments of the present application provide a cell search apparatus, which includes each unit included and each module included in each unit, which can be implemented by a processor in a terminal device; of course, it can also be implemented by The specific logic circuit is realized.

FIG. 16 is a schematic diagram of the composition and structure of a cell search apparatus according to an embodiment of the present application. As shown in FIG. 16 , the cell search apparatus 1600 includes:

The processing module 1601 is used to perform a cross-correlation operation on the first PSS frequency domain data and the local PSS sequence to obtain a first correlation sequence; the first PSS frequency domain data is the received time domain data after the interference is eliminated from the PSS frequency domain data;

Compensation module 1602, configured to perform time offset compensation on the first transformed sequence obtained by discrete transformation of the first correlation sequence based on the preset first time offset value, to obtain a first correlated compensation sequence;

The determining module 1603 is configured to determine the information of the target cell based on the first correlation compensation sequence, the first time offset value and the first SSS frequency domain data; the first SSS frequency domain data is the SSS after interference cancellation in the received time domain data frequency domain data.

In some embodiments, the processing module 1601 is further configured to perform discrete transformation on the first correlation sequence to obtain the first transformed sequence; the compensation module 1602 is further configured to determine the offset first time offset value from the first transformed sequence The first correlation compensation sequence corresponding to the time is used to complete the time offset compensation.

In some embodiments, the determining module 1603 is further configured to determine a second time offset value based on the first time offset value and the first correlation compensation sequence; the processing module 1601 is further configured to determine the first time offset value based on the second time offset value The second correlation sequence after the cross-correlation operation between the SSS frequency domain data and the local SSS sequence is performed to perform time offset compensation to obtain a second correlation compensation sequence; the determining module 1603 is further configured to, based on the first correlation compensation sequence and the second correlation compensation sequence, Determine the information of the target cell.

In some embodiments, the determining module 1603 is further configured to determine the first candidate peak based on the first time offset value and the first correlation compensation sequence; the processing module 1601 is further configured to associate the first candidate peak with the first PSS frequency domain A remainder operation is performed on the length of the data to obtain the second time offset value.

In some embodiments, the first time offset values include: W first time offset values, where W is an integer greater than or equal to 1; each first time offset value corresponds to N1 first sub-correlation compensation sequences, and the first correlation The compensation sequence includes N1 first sub-correlation compensation sequences corresponding to the W first time offset values, where N1 is an integer greater than or equal to 1; the determining module 1603 is further configured to, for each first time offset value, based on the N1 In the first sub-correlation compensation sequence, N1 first peaks are determined; for W first time offset values, from W×N1 first peaks, U first candidate peaks that are greater than or equal to the first preset peak threshold are determined ; U is an integer greater than or equal to 1 and less than or equal to W×N1.

In some embodiments, the cell search apparatus further includes an obtaining module 1604, the obtaining module 1604 is configured to obtain, for each first time offset value, based on the N1 first sub-correlation compensation sequences, obtain the corresponding correspondence of each first sub-correlation compensation sequence The determination module 1603 is further configured to determine the first peak corresponding to each first sub-correlation compensation sequence based on the energy distribution information corresponding to each first sub-correlation compensation sequence, thereby obtaining N1 first sub-correlations The N1 first peaks corresponding to the compensation sequence.

In some embodiments, the processing module 1601 is further configured to perform a remainder operation between each first candidate peak and the length of the first PSS frequency domain data to obtain at least one second time offset value.

In some embodiments, the processing module 1601 is further configured to perform a cross-correlation operation on the first SSS frequency domain data and the local SSS sequence to obtain a second correlation sequence; perform discrete transformation on the second correlation sequence to obtain a second transformed sequence; The compensation module 1602 is further configured to determine, from the second transformation sequence, a second correlation compensation sequence corresponding to the offset of the second time offset value, so as to complete the time offset compensation.

In some embodiments, the obtaining module 1604 is further configured to obtain a first candidate peak value corresponding to the first correlation compensation sequence; wherein the first candidate peak value corresponds to a first time offset value and a local PSS sequence; the determining module 1603 is further configured to for determining a second candidate peak based on the second time offset value and the second correlation compensation sequence; wherein the second candidate peak corresponds to a second time offset value and a local SSS sequence; based on the first candidate peak and the second candidate peak , to determine the information of the target cell.

In some embodiments, the second time offset values include: P second time offset values, where P is an integer greater than or equal to 1 and less than or equal to W; each second time offset value corresponds to N2 second sub-correlations Compensation sequence, the second correlation compensation sequence includes N2 second sub-correlation compensation sequences corresponding to the P second time offset values respectively, and N2 is an integer greater than or equal to 1; the determining module 1603 is further configured for each second time offset value. Offset value, based on N2 second sub-correlation compensation sequences, determine N2 second peaks; for P second time offset values, from P×N2 second peaks, determine a value greater than or equal to the second preset peak threshold Q second candidate peaks; Q is an integer greater than or equal to 1 and less than or equal to P×N2.

In some embodiments, the processing module 1601 is further configured to perform data transformation on the received time domain data of multiple cells to obtain second PSS frequency domain data and second SSS frequency domain data; , obtain the first PSS frequency domain data for the reconstructed PSS frequency domain data of the known cells of the same frequency; and eliminate the SSS frequency domain data reconstructed for the known cells of the same frequency in the second SSS frequency domain data to obtain The first SSS frequency domain data.

In some embodiments, the processing module 1601 is further configured to obtain the first channel frequency response of the known cell based on least squares parameter estimation on the second SSS frequency domain data; The local PSS sequence is reconstructed to obtain the PSS frequency domain reconstruction data of the known cell; the PSS frequency domain reconstruction data in the second PSS frequency domain data is eliminated to obtain the first PSS frequency domain data.

In some embodiments, the processing module 1601 is further configured to reconstruct the local SSS sequence of the known cell by using the first channel frequency response to obtain the SSS frequency domain reconstruction data of the known cell; eliminate the second SSS frequency domain data The SSS frequency domain reconstruction data in , obtains the first SSS frequency domain data.

In some embodiments, the processing module 1601 is further configured to perform least squares parameter estimation on the second SSS frequency domain data to obtain the second channel frequency response of the known cell; Filter to obtain the first channel frequency response.

In some embodiments, the first PSS frequency domain data is PSS frequency domain data obtained after the received time domain data cancels the interference of the known cell, and the processing module 1601 is further configured to update the first PSS with the target cell as the known cell The frequency domain data and the first SSS frequency domain data, and based on the updated first PSS frequency domain data and the updated first SSS frequency domain data, determine the next target cell information until a preset stop condition is reached.

The descriptions of the above apparatus embodiments are similar to the descriptions of the above method embodiments, and have similar beneficial effects to the method embodiments. For technical details not disclosed in the device embodiments of the present application, please refer to the descriptions of the method embodiments of the present application for understanding.

It should be noted that, in the embodiments of the present application, if the above cell search method is implemented in the form of a software function module and sold or used as an independent product, it may also be stored in a computer storage medium. Based on such understanding, the technical solutions of the embodiments of the present application may be embodied in the form of software products in essence or the parts that contribute to related technologies. The computer software products are stored in a storage medium and include several instructions to make A terminal device executes all or part of the methods described in the various embodiments of this application.

FIG. 17 is a schematic structural diagram of a device according to an embodiment of the present application. The device 1700 shown in FIG. 17 includes a processor 1701 and a memory 1702,

The memory 1702 stores computer programs executable on the processor 1701,

When the processor 1701 executes the computer program, it implements the steps of the cell search method in any of the above embodiments.

The device in this embodiment of the present application may be a terminal device or a chip. Herein, the terminal equipment may be referred to as a terminal (Terminal), user equipment (user equipment, UE), a mobile station (mobile station, MS), a mobile terminal (mobile terminal, MT), and the like. The electronic device here may include one of the following or at least a combination of both: Internet of Things (IoT) devices, satellite terminals, Wireless Local Loop (WLL) stations, Personal Digital Assistant (Personal Digital Assistant) , PDA), handheld device with wireless communication function, computing device or other processing device connected to wireless modem, server, mobile phone (mobile phone), tablet computer (Pad), computer with wireless transceiver function, palmtop computer, desktop computer , personal digital assistants, portable media players, smart speakers, navigation devices, smart watches, smart glasses, smart necklaces and other wearable devices, pedometers, digital TVs, virtual reality (Virtual Reality, VR) terminal equipment, augmented reality (Augmented Reality, AR) terminal equipment, wireless terminals in industrial control, wireless terminals in self driving, wireless terminals in remote medical surgery, smart grid wireless terminal in transportation safety, wireless terminal in smart city, wireless terminal in smart home, and car, in-vehicle equipment, in-vehicle module in car networking system , wireless modem (modem), handheld device (handheld), customer terminal equipment (Customer Premise Equipment, CPE), smart home appliances and so on.

The processor 1701 in the above-mentioned device 1700 may be a chip, such as an integrated circuit chip, which has signal processing capability. In the implementation process, each step of the above method embodiments may be completed by a hardware integrated logic circuit in a processor or an instruction in the form of software.

The above-mentioned processor 1701 may also be a general-purpose processor, a digital signal processor (Digital Signal Processor, DSP), an application specific integrated circuit (Application Specific Integrated Circuit, ASIC), an off-the-shelf programmable gate array (Field Programmable Gate Array, FPGA) or other Programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The methods, steps, and logic block diagrams disclosed in the embodiments of this application can be implemented or executed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in conjunction with the embodiments of the present application may be directly embodied as executed by a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor.

Embodiments of the present application may further provide a computer storage medium, where one or more programs are stored in the computer storage medium, and the one or more programs can be executed by one or more processors to implement the cell search in any of the above embodiments steps of the method.

It should be pointed out here that the descriptions of the above storage medium and terminal device embodiments are similar to the descriptions of the above method embodiments, and have similar beneficial effects to the method embodiments. For technical details not disclosed in the embodiments of the storage medium and terminal device of the present application, please refer to the description of the method embodiments of the present application to understand.

The above-mentioned computer storage medium/memory may include the integration of one or more of the following: a read-only memory (Read Only Memory, ROM), a programmable read-only memory (Programmable Read-Only Memory, PROM), an erasable programmable only memory Read Memory (Erasable Programmable Read-Only Memory, EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Magnetic Random Access Memory (Ferromagnetic Random Access Memory, FRAM), Flash Memory (FlashMemory), magnetic surface memory, CD, CD-ROM (Compact Disc Read-Only Memory, CD-ROM) and other memories; can also be various terminals including one or any combination of the above memories, such as mobile phones, computers , tablet devices, personal digital assistants, etc.

It should be understood that references throughout the specification to "one embodiment" or "an embodiment" or "an embodiment of the present application" or "the preceding embodiments" or "some implementations" or "some embodiments" mean that A particular feature, structure, or characteristic of an example is included in at least one embodiment of the present application. Thus, the appearances of "in one embodiment" or "in an embodiment" or "the present embodiment" or "the preceding embodiments" or "some implementations" or "some embodiments" in various places throughout the specification are not necessarily Must refer to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments. It should be understood that, in various embodiments of the present application, the size of the sequence numbers of the above-mentioned processes does not mean the sequence of execution, and the execution sequence of each process should be determined by its functions and internal logic, and should not be dealt with in the embodiments of the present application. implementation constitutes any limitation. The above-mentioned serial numbers of the embodiments of the present application are only for description, and do not represent the advantages or disadvantages of the embodiments.

Unless otherwise specified, the terminal device performs any step in the embodiments of the present application, which may be performed by a processor of the terminal device. Unless otherwise specified, the embodiments of the present application do not limit the sequence in which the terminal device performs the following steps. In addition, the manner in which data is processed in different embodiments may be the same method or different methods. It should also be noted that, any step in the embodiments of the present application can be independently executed by the terminal device, that is, when the terminal device executes any step in the foregoing embodiments, it may not depend on the execution of other steps.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other manners. The device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined, or Can be integrated into another system, or some features can be ignored, or not implemented. In addition, the coupling, or direct coupling, or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be electrical, mechanical or other forms. of.

The unit described above as a separate component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit; it may be located in one place or distributed to multiple network units; Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present application may all be integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above integration The unit can be implemented either in the form of hardware or in the form of hardware plus software functional units.

The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined under the condition of no conflict to obtain new method embodiments.

The features disclosed in the several product embodiments provided in this application can be combined arbitrarily without conflict to obtain a new product embodiment.

The features disclosed in several method or device embodiments provided in this application can be combined arbitrarily without conflict to obtain new method embodiments or device embodiments.

Those of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by program instructions related to hardware, the aforementioned program can be stored in a computer storage medium, and when the program is executed, the execution includes the implementation of the above method. The above-mentioned storage medium includes: a removable storage device, a read only memory (Read Only Memory, ROM), a magnetic disk or an optical disk and other media that can store program codes.

Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software function module and sold or used as an independent product, it may also be stored in a computer storage medium. Based on such understanding, the technical solutions of the embodiments of the present application may be embodied in the form of software products in essence or the parts that contribute to related technologies. The computer software products are stored in a storage medium and include several instructions to make A computer device (which may be a personal computer, a server, or a network device, etc.) executes all or part of the methods described in the various embodiments of the present application. The aforementioned storage medium includes various media that can store program codes, such as a removable storage device, a ROM, a magnetic disk, or an optical disk.

In the embodiments of the present application, the descriptions of the same steps and the same contents in different embodiments can be referred to each other. In this embodiment of the present application, the term "does not" does not affect the sequence of steps. For example, if the terminal device executes A and then executes B, the terminal device may execute A first and then execute B, or the terminal device executes B first. Execute A again, or execute B while the terminal device executes A.

As used in the embodiments of this application and the appended claims, the singular forms "a," "the," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise.

It should be noted that, in each embodiment involved in this application, all the steps or part of the steps may be performed, as long as a complete technical solution can be formed.

The above is only the embodiment of the present application, but the protection scope of the present application is not limited to this. Covered within the scope of protection of this application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims (18)

1. A method of cell search, comprising:

performing cross-correlation operation on the frequency domain data of the first primary synchronization signal PSS and the local PSS sequence to obtain a first correlation sequence; the first PSS frequency domain data is the PSS frequency domain data after interference of the received time domain data is eliminated;

respectively performing time offset compensation on a first conversion sequence after the first correlation sequence is subjected to discrete conversion based on a preset first time offset value to obtain a first correlation compensation sequence;

determining information of a target cell based on the first correlation compensation sequence, the first time offset value and first Secondary Synchronization Signal (SSS) frequency domain data; the first SSS frequency domain data is SSS frequency domain data with interference eliminated from received time domain data.

2. The method according to claim 1, wherein the performing time offset compensation on the first transform sequence after fourier transform on the first correlation sequence based on a preset first time offset value to obtain a first correlation compensation sequence comprises:

performing discrete transformation on the first correlation sequence to obtain a first transformation sequence;

and determining the first correlation compensation sequence corresponding to the first time offset value in the first transformation sequence so as to complete the time offset compensation.

3. The method of claim 1 or 2, wherein the determining information of the target cell based on the first correlation compensation sequence, the first time offset value and first SSS frequency domain data comprises:

determining a second time offset value based on the first time offset value and the first correlation compensation sequence;

performing time offset compensation on a second correlation sequence obtained after performing cross-correlation operation on the first SSS frequency domain data and a local SSS sequence based on the second time offset value to obtain a second correlation compensation sequence;

determining information of the target cell based on the first correlation compensation sequence and the second correlation compensation sequence.

4. The method of claim 3, wherein determining a second time offset value based on the first time offset value and the first correlation compensation sequence comprises:

determining a first candidate peak based on the first time offset value and the first correlation compensation sequence;

and performing remainder operation on the first candidate peak value and the length of the first PSS frequency domain data to obtain the second time offset value.

5. The method of claim 4, wherein the first time offset value comprises: w first time offset values, W being an integer greater than or equal to 1; each first time offset value corresponds to N1 first sub-correlation compensation sequences, the first correlation compensation sequences include N1 first sub-correlation compensation sequences corresponding to W first time offset values, N1 is an integer greater than or equal to 1;

determining a first candidate peak based on the first time offset value and the first correlation compensation sequence, comprising:

determining N1 first peaks based on the N1 first sub-correlation compensation sequences for the each first time offset value;

determining, for the W first time offset values, U first candidate peaks from among W × N1 first peaks, which are greater than or equal to a first preset peak threshold; u is an integer greater than or equal to 1 and less than or equal to W × N1.

6. The method of claim 5, wherein the determining N1 first peaks for the each first time offset value based on the N1 first sub-correlation compensation sequences comprises:

for each first time offset value, acquiring energy distribution information corresponding to each first sub-correlation compensation sequence based on the N1 first sub-correlation compensation sequences;

and determining a first peak value corresponding to each first sub-correlation compensation sequence based on the energy distribution information corresponding to each first sub-correlation compensation sequence, so as to obtain N1 first peak values corresponding to N1 first sub-correlation compensation sequences.

7. The method of claim 5 or 6, wherein the subtracting the length of the first PSS frequency domain data from the first candidate peak to obtain the second time offset value comprises:

and performing remainder operation on each first candidate peak value and the length of the first PSS frequency domain data to obtain at least one second time offset value.

8. The method according to any one of claims 3 to 7, wherein the performing time offset compensation on the second correlation sequence obtained by performing cross-correlation operation on the first SSS frequency-domain data and a local SSS sequence based on the second time offset value to obtain a second correlation compensation sequence comprises:

performing cross-correlation operation on the first SSS frequency domain data and the local SSS sequence to obtain a second correlation sequence;

performing discrete transformation on the second correlation sequence to obtain a second transformation sequence;

and determining the second relevant compensation sequence corresponding to the second time offset value in the second transformation sequence so as to complete the time offset compensation.

9. The method according to any of claims 4 to 7, wherein the determining the information of the target cell based on the first correlation compensation sequence and the second correlation compensation sequence comprises:

determining a second candidate peak based on the second time offset value and the second correlation compensation sequence; wherein the second candidate peak corresponds to a second time offset value and a local SSS sequence;

determining information of the target cell based on the first candidate peak and the second candidate peak corresponding to the first correlation compensation sequence; the first candidate peak corresponds to a first time offset value and a local PSS sequence.

10. The method of claim 9, wherein the second time offset value comprises: p second time offset values, wherein P is an integer which is greater than or equal to 1 and less than or equal to W; each second time offset value corresponds to N2 second sub-correlation compensation sequences, the second correlation compensation sequences include N2 second sub-correlation compensation sequences corresponding to P second time offset values, N2 is an integer greater than or equal to 1;

determining a second candidate peak based on the second time offset value and the second correlation compensation sequence, including:

determining N2 second peaks based on the N2 second sub-correlation compensation sequences for the each second time offset value;

determining, for the P second time offset values, Q second candidate peaks from among P × N2 second peaks, which are greater than or equal to a second preset peak threshold; q is an integer greater than or equal to 1 and less than or equal to P × N2.

11. The method of any of claims 1 to 10, wherein before performing the cross-correlation of the first PSS frequency-domain data with the local PSS sequence to obtain the first correlation sequence, the method comprises:

performing data transformation on the received time domain data of the plurality of cells to obtain second PSS frequency domain data and second SSS frequency domain data;

eliminating the PSS frequency domain data reconstructed aiming at the known cells with the same frequency in the second PSS frequency domain data to obtain the first PSS frequency domain data; and eliminating SSS frequency domain data reconstructed by the known cell with the same frequency in the second SSS frequency domain data to obtain the first SSS frequency domain data.

12. The method of claim 11, wherein the eliminating of the PSS frequency domain data reconstructed for the co-frequency known cell from the second PSS frequency domain data to obtain the first PSS frequency domain data comprises:

performing least square parameter estimation on the second SSS frequency domain data to obtain a first channel frequency response of the known cell;

reconstructing the local PSS sequence of the known cell through the first channel frequency response to obtain PSS frequency domain reconstruction data of the known cell;

and eliminating the PSS frequency domain reconstruction data in the second PSS frequency domain data to obtain the first PSS frequency domain data.

13. The method of claim 12, wherein the eliminating of the SSS frequency-domain data reconstructed for a known cell of a same frequency from the second SSS frequency-domain data to obtain the first SSS frequency-domain data comprises:

reconstructing a local SSS sequence of the known cell through the first channel frequency response to obtain SSS frequency domain reconstruction data of the known cell;

and eliminating the SSS frequency domain reconstruction data in the second SSS frequency domain data to obtain the first SSS frequency domain data.

14. The method of claim 12, wherein obtaining the first channel frequency response of the known cell based on least squares parameter estimation of the second SSS frequency-domain data comprises:

performing least square parameter estimation on the second SSS frequency domain data to obtain a second channel frequency response of the known cell;

and filtering the second channel frequency response by adopting the minimum mean square error to obtain the first channel frequency response.

15. The method of any of claims 1 to 14, wherein the first PSS frequency domain data is PSS frequency domain data obtained by eliminating interference of a known cell from received time domain data, and wherein after determining the information of the target cell, the method further comprises:

and taking the target cell as a known cell, updating the first PSS frequency domain data and the first SSS frequency domain data, and determining the information of the next target cell based on the updated first PSS frequency domain data and the updated first SSS frequency domain data until a preset stop condition is reached.

16. A cell search apparatus, comprising:

the processing module is used for performing cross-correlation operation on the frequency domain data of the first primary synchronization signal PSS and the local PSS sequence to obtain a first correlation sequence; the first PSS frequency domain data is the PSS frequency domain data after interference of the received time domain data is eliminated;

the compensation module is used for respectively carrying out time offset compensation on a first conversion sequence after the first correlation sequence is subjected to discrete conversion based on a preset first time offset value to obtain a first correlation compensation sequence;

a determining module, configured to determine information of a target cell based on the first correlation compensation sequence, the first time offset value, and first secondary synchronization signal SSS frequency-domain data; the first SSS frequency domain data is SSS frequency domain data with interference eliminated from received time domain data.

17. An apparatus, characterized in that the apparatus comprises: a processor and a memory, wherein the processor is capable of processing a plurality of data,

the memory stores a computer program operable on the processor,

the processor, when executing the computer program, implements the method of any of claims 1 to 15.

18. A computer-readable storage medium storing a computer program for causing a computer to perform the method of any one of claims 1 to 15.

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