Pilot signal detection method and apparatus based on complex value combination

Abstract

The application provides a secondary synchronization signal detection method and device based on complex value merging and related equipment. The method comprises: obtaining antenna data received by an antenna; extracting a secondary synchronization signal from the antenna data; respectively demultiplexing each half-frame sequence signal in the secondary synchronization signal to obtain a first descrambling sequence and a second descrambling sequence corresponding to each of the different half-frame sequence signals; the first descrambling sequence and the second descrambling sequence comprise complex values related to NID1 of the secondary synchronization signal; merging the first descrambling sequence and the second descrambling sequence of each half-frame sequence signal to obtain a corresponding intra-half-frame complex value merging sequence; and detecting synchronization information based on the intra-half-frame complex value merging sequence. The method can improve the detection performance of synchronization information in the secondary synchronization signal.

Description

Technical Field

[0001] This application relates to the field of communications, and specifically, provides a method, apparatus, and related equipment for detecting auxiliary synchronization signals based on complex value combining. Background Technology

[0002] In a communication system, when the transmitting and receiving devices communicate, they need to synchronize.

[0003] LTE (Long Term Evolution) provides a synchronization method. LTE technology specifies PSS (Primary Synchronization Signal) and SSS (Secondary Synchronization Signal). Transmitting and receiving devices can use PSS and SSS to search for and synchronize with base station cells, thereby enabling synchronization between the transmitting and receiving devices.

[0004] Communication equipment needs to detect synchronization information in PSS and SSS in order to synchronize with the base station cell through the synchronization information. For example, the synchronization information includes unique identification information, timing, frequency offset, cyclic prefix type, etc.

[0005] The relatively small number of secondary synchronization signals (PSS) reduces the complexity of the primary synchronization signal, resulting in high accuracy in its detection. In contrast, the large number of secondary synchronization signals, such as the 168 possible values ​​for the unique identifier NID1 of a PSS, makes detection more complex. Furthermore, some current methods for detecting PSS signals lead to performance degradation, consequently reducing detection accuracy and success rate. Summary of the Invention

[0006] In view of this, this application aims to provide a method, apparatus and related equipment for detecting auxiliary synchronization signals based on complex value merging, so as to improve the accuracy and detection performance of detecting each synchronization information in the auxiliary synchronization signal.

[0007] In a first aspect, this application provides a method for detecting an auxiliary synchronization signal based on complex value combining, comprising: acquiring antenna data received by an antenna; extracting an auxiliary synchronization signal from the antenna data; the auxiliary synchronization signal comprising two half-frame sequence signals; demultiplexing each of the half-frame sequence signals in the auxiliary synchronization signal to obtain a first descrambling sequence and a second descrambling sequence corresponding to each of the different half-frame sequence signals; the first descrambling sequence and the second descrambling sequence comprising complex values ​​related to a unique signal identifier NID1 of the auxiliary synchronization signal; performing complex value combining on the first descrambling sequence and the second descrambling sequence of each of the half-frame sequence signals to obtain an intra-half-frame complex value combining sequence corresponding to each of the half-frame sequence signals; the complex value combining is used to combine complex values ​​related to NID1; and performing synchronization information detection based on the intra-half-frame complex value combining sequence.

[0008] The signal received by the receiving device contains the sum of the transmitted signal and noise. When the noise increases beyond the single signal detection threshold, signal detection will fail. The auxiliary synchronization signals transmitted multiple times in different periods are identical, but each contains different noise. Therefore, in this embodiment, the half-frame sequence signals of the auxiliary synchronization signals can be merged to reduce signal variance and suppress noise. This improves detection performance when performing synchronization information detection based on the merged signal. In this application, the first and second descrambling sequences are merged based on complex values. Compared to some power-based merging methods, complex values ​​can preserve the phase information of the signal. This allows the merged half-frame complex value merged sequence to retain phase information, thereby improving the accuracy of synchronization information detection through phase information.

[0009] In one embodiment, extracting the secondary synchronization signal from the antenna data includes: acquiring a primary synchronization signal and an initial secondary synchronization signal extracted from the antenna data; performing channel estimation on the primary synchronization signal to obtain a channel estimation value; and performing channel compensation on the initial secondary synchronization signal based on the channel estimation value to obtain the secondary synchronization signal.

[0010] Different secondary synchronization signals may be received by channels of different antennas. Since different antennas experience different fading, the secondary synchronization signals are affected by the channel, potentially leading to discrepancies in the actual received signals. In the embodiments of this application, channel compensation can be performed on the secondary synchronization signals to eliminate channel influence, ensuring consistency of information within each signal and enabling merging. Furthermore, LTE duplex mode specifies the position of the PSS symbol of each SSS symbol within its respective signal. If the sampling rates of the secondary and primary synchronization signals are at their lowest values, a non-integer sampling deviation between the PSS symbols of the SSS symbols may occur during time-frequency domain conversion. This can result in a phase difference when equalizing the SSS signals using PSS channel estimation. Therefore, to ensure an integer sampling deviation between the PSS symbols of the SSS symbols, the sampling rate typically needs to be increased. This application, however, compensates for the secondary synchronization signals based on the primary synchronization signal, effectively reducing or avoiding the impact of phase differences. This allows for signal sampling at the lowest possible sampling rate, reducing power consumption, computational complexity, and storage complexity.

[0011] In one embodiment, after performing channel compensation on the initial secondary synchronization signal based on the channel estimate to obtain the secondary synchronization signal, the method further includes: performing energy normalization processing on the secondary synchronization signal based on a preset normalization method; the step of demultiplexing different half-frame sequence signals in the secondary synchronization signal includes: demultiplexing different half-frame sequence signals in the secondary synchronization signal after the energy normalization processing.

[0012] In this embodiment of the application, it is necessary to merge half-frame sequence signals of different auxiliary synchronization signals. However, when receiving signals, the fading amplitude of different channels is different, and the receiving gain used may be different. Therefore, in order to avoid the influence of different receiving gains on the reception of auxiliary synchronization signals, it is necessary to normalize the energy of the auxiliary synchronization signals to obtain more accurate auxiliary synchronization signals.

[0013] In one embodiment, the step of performing channel estimation on the primary synchronization signal to obtain a channel estimation value includes: performing channel estimation on the data corresponding to each sampling point of the primary synchronization signal to obtain multiple original channel estimation values; the primary synchronization signal includes multiple sampling points and their corresponding data, each sampling point corresponding to one original channel estimation value; calculating the power value corresponding to each original channel estimation value; and selecting an original channel estimation value whose power value is greater than a first preset power threshold from the multiple original channel estimation values ​​as the channel estimation value.

[0014] The signal will travel through multiple paths to reach the receiver. Different paths will have a certain impact on the signal. When the path power is low, it will cause greater noise interference to the signal. Therefore, in this embodiment, the power value corresponding to each of the original channel estimates is calculated. The power corresponding to each path is determined. The path with power greater than a first preset power threshold is selected, and the original channel estimate corresponding to the path is used as the required channel estimate. This method can reduce or even eliminate the noise impact of the path on the master synchronization signal, thereby improving the accuracy of the determined channel estimate.

[0015] In one embodiment, the channel estimate is a time-domain estimate; the initial secondary synchronization signal is a time-domain signal; the channel compensation based on the channel estimate includes: performing a time-frequency domain conversion on the channel estimate and demapping it based on a preset signal resource mapping method to obtain a frequency-domain estimate of the primary synchronization signal; acquiring the time-domain data of the initial secondary synchronization signal under different cyclic prefix types based on a preset duplex mode; for each cyclic prefix type, performing an FFT time-frequency domain conversion on the time-domain data of the initial secondary synchronization signal corresponding to that cyclic prefix type and demapping it based on a preset signal resource mapping method to obtain the frequency-domain data of the initial secondary synchronization signal; and performing channel compensation on the time-domain data of the initial secondary synchronization signal based on the frequency-domain estimate of the primary synchronization signal to obtain the secondary synchronization signal.

[0016] In this embodiment, both the primary synchronization signal and the initial secondary synchronization signal are time-domain signals, requiring conversion to the frequency domain for channel compensation. During the detection phase, the cyclic prefix type is not yet determined; therefore, different cyclic prefix types need to be assumed, and time-domain data of the initial secondary synchronization signal under each cyclic prefix type needs to be acquired for subsequent processing to obtain the secondary synchronization signals corresponding to different cyclic prefix types. Channel compensation reduces the possibility of non-integer sampling deviations between SSS and PSS symbols caused by time-frequency domain conversion, thus avoiding phase differences. Furthermore, the lowest sampling rate can be used for signal sampling, reducing power consumption, computational complexity, and storage complexity.

[0017] In one embodiment, the step of demultiplexing each of the half-frame sequence signals in the auxiliary synchronization signal to obtain a first descrambling sequence and a second descrambling sequence corresponding to each of the different half-frame sequence signals includes: obtaining the unique identifier information NID2 of the primary synchronization signal; for any half-frame sequence signal, splitting the half-frame sequence signal based on the parity of the carrier sequence number to obtain odd subcarrier data and even subcarrier data; descrambling the even subcarrier data based on NID2 and a preset first c sequence to obtain descrambled even subcarrier data; converting the descrambled even subcarrier data into an m sequence based on a preset m sequence conversion method to obtain the first descrambling sequence; descrambling the odd subcarrier data based on NID2, a preset second c sequence, and a z sequence to obtain descrambled odd subcarrier data; and converting the descrambled odd subcarrier data into the m sequence based on the preset m sequence conversion method to obtain the second descrambling sequence.

[0018] In this embodiment, the half-frame sequence signal is descrambled into even-subcarrier data and odd-subcarrier data. Based on this, the auxiliary synchronization signal can undergo an additional merging process—that is, merging the even-subcarrier data and odd-subcarrier data—to improve noise immunity. Furthermore, the even-subcarrier data and odd-subcarrier data are converted into an m-sequence. This m-sequence can be calculated using the Fast Möbius Transform (FMT). Compared to other calculation methods, FMT calculation has lower computational complexity, improving computational efficiency and thus enhancing the detection efficiency of synchronization information.

[0019] In one embodiment, the complex value merging of the first descrambling sequence and the second descrambling sequence of each of the half-frame sequence signals includes: exchanging the first descrambling sequence and the second descrambling sequence of each of the two half-frame sequence signals within the same auxiliary synchronization signal; and for the two half-frame sequence signals within the same auxiliary synchronization signal, merging the exchanged first descrambling sequence and the second descrambling sequence respectively to obtain the complex value merged sequence within the half-frame corresponding to each of the different half-frame sequence signals.

[0020] Since the timing of the detection phase has not yet been determined, subframes 0 and 5 in the auxiliary synchronization signal are reciprocal. Based on this, in this embodiment, the first and second descrambling sequences of the two half-frame sequence signals within the same auxiliary synchronization signal are exchanged, which helps to average the signal variance, reduce the influence of noise, and improve the detection accuracy of the auxiliary synchronization signal.

[0021] In one embodiment, before performing synchronization information detection on the intra-frame complex-valued merged sequence, the method further includes: obtaining intra-frame complex-valued merged sequences corresponding to the respective intra-frame sequence signals of different auxiliary synchronization signals; performing complex value merging on the intra-frame complex-valued merged sequences corresponding to the respective intra-frame sequence signals of different auxiliary synchronization signals to obtain inter-frame complex-valued merged sequences; and performing synchronization information detection based on the intra-frame complex-valued merged sequence includes: performing synchronization information detection on the inter-frame complex-valued merged sequence.

[0022] In this embodiment of the application, the merging of the auxiliary synchronization signal includes two steps. In addition to the merging of the carrier after descrambling the half-frame sequence signal in the aforementioned auxiliary synchronization signal, the merging of half-frame sequence signals of multiple different auxiliary synchronization signals can also be performed. Compared with single merging, multiple merging can more effectively suppress noise and further improve the accuracy of synchronization information detection.

[0023] In one embodiment, the step of performing complex value merging on the intra-half-frame complex value merging sequences corresponding to each of the different auxiliary synchronization signals to obtain an inter-half-frame complex value merging sequence includes: for each half-frame sequence signal, determining whether the half-frame sequence signal is the same as the first half-frame sequence signal determined from the antenna data, and generating half-frame similarity / difference indication information corresponding to the half-frame sequence signal; the half-frame similarity / difference indication information indicates whether the half-frame sequence signal is the same as the first half-frame sequence signal; wherein, in the half-frame similarity / difference indication information indicating whether the half-frame sequence signal is the same as the first half-frame sequence signal; When the half-frame sequence signal is the same as the first half-frame sequence signal, the intra-frame complex value merging sequence of the half-frame sequence signal is merged with the historical inter-frame complex value merging sequence; the historical inter-frame complex value merging sequence includes those obtained by merging multiple intra-frame complex value merging sequences; when the half-frame difference indication information indicates that the half-frame sequence signal is different from the first half-frame sequence signal, the intra-frame complex value merging sequences of the two half-frame sequence signals in the auxiliary synchronization signal where the half-frame sequence signal is located are swapped and then merged with the historical inter-frame complex value merging sequence.

[0024] The merging of half-frame complex-valued merged sequences involves combining half-frame complex-valued merged sequences corresponding to the same half-frame sequence signal. During the detection phase, the frame timing is not yet determined, making it impossible to distinguish half-frame sequence signals. Therefore, in this embodiment, the type is determined by whether it is the same as the first frame half-frame sequence signal. Merging half-frame sequence signals with different auxiliary synchronization signals helps to average the signal variance and reduce the impact of noise. Furthermore, the more auxiliary synchronization signals merged, the smaller the noise impact and the higher the noise immunity.

[0025] In one embodiment, the synchronization information detection of the inter-frame complex-valued merged sequence includes: calculating the power value corresponding to the inter-frame complex-valued merged sequence under each combination of various preset half-frame types and various preset CP types to obtain a target power group; searching out the P power values ​​with the largest power from the target power group; if there is a power value among the P power values ​​that is greater than a second preset power threshold, then determining the synchronization information based on the peak power of the P power values.

[0026] In this embodiment, since the half-frame type and CP type of the auxiliary synchronization signal corresponding to the half-frame sequence signal have not yet been determined during the detection stage, assumptions and combinations can be made about the half-frame type and CP type to calculate the power values ​​under different conditions, and the synchronization information of the auxiliary synchronization signal can be determined through the power peak value. This method considers different scenarios and can improve the accuracy of detection.

[0027] Secondly, embodiments of this application provide an auxiliary synchronization signal detection device based on complex value combining, comprising: an acquisition unit for acquiring antenna data received by an antenna; a channel equalization unit for extracting an auxiliary synchronization signal from the antenna data; the auxiliary synchronization signal comprising two half-frame sequence signals; a descrambling unit for demultiplexing each of the half-frame sequence signals in the auxiliary synchronization signal to obtain a first descrambling sequence and a second descrambling sequence corresponding to each of the different half-frame sequence signals; the first descrambling sequence and the second descrambling sequence comprising complex values ​​related to the unique signal identifier NID1 of the auxiliary synchronization signal; a half-frame complex value combining unit for combining the first descrambling sequence and the second descrambling sequence of each of the half-frame sequence signals to obtain a half-frame intra-complex value combining sequence corresponding to each of the half-frame sequence signals; the complex value combining is used to combine the complex values ​​related to NID1; and a detection unit for detecting synchronization information based on the half-frame intra-complex value combining sequence.

[0028] Thirdly, embodiments of this application provide a communication module for performing the auxiliary synchronization signal detection method based on complex value merging as described in any of the first aspects.

[0029] Fourthly, embodiments of this application provide an electronic device including a communication module, the communication module being used to perform the auxiliary synchronization signal detection method based on complex value combining as described in any of the first aspects.

[0030] Fifthly, embodiments of this application provide a readable storage medium, characterized in that it includes: a program stored in the readable storage medium, which, when the program is run on a communication module, causes the communication module to implement the auxiliary synchronization signal detection method based on complex value merging as described in any of the first aspects.

[0031] In a sixth aspect, embodiments of this application provide a computer program product, the computer program product including a computer program, which, when executed by a communication module, implements the auxiliary synchronization signal detection method based on complex value merging as described in any of the first aspects. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a timing diagram illustrating different duplex modes provided in an embodiment of this application; Figure 2 A flowchart illustrating a method for detecting auxiliary synchronization signals based on complex value combining, provided in an embodiment of this application; Figure 3 This is a schematic diagram of the entire process of the auxiliary synchronization signal channel provided in an embodiment of this application; Figure 4 This is a schematic diagram of a demultiplexing process provided in an embodiment of this application; Figure 5 This is a schematic diagram of the merging of a half-frame intra-complex value merging sequence provided in an embodiment of this application; Figure 6 This is a schematic diagram of the merging of half-frame complex value merging sequences provided in an embodiment of this application; Figure 7 This is a schematic diagram of synchronization information detection provided in an embodiment of this application; Figure 8 This is a schematic diagram illustrating the accuracy of AWGN channel auxiliary synchronization signal detection according to an embodiment of this application; Figure 9 This is a schematic diagram illustrating the accuracy of auxiliary synchronization signal detection in the EUT70 channel according to an embodiment of this application; Figure 10 This is a schematic diagram of an auxiliary synchronization signal detection device based on complex value merging, provided as an embodiment of this application.

[0034] Icon: Auxiliary synchronization signal detection device 100 based on complex value combining; acquisition unit 101; channel equalization unit 102; descrambling unit 103; intra-half frame complex value combining unit 104; inter-half frame complex value combining module 105; detection unit 105. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0036] This application provides a method for detecting secondary synchronization signals based on complex-valued combining, which can be applied to communication modules equipped with LTE technology. For ease of understanding, some aspects of LTE technology will be explained first.

[0037] In LTE systems, user terminals need to obtain synchronization and broadcast information from base stations to communicate with them. LTE technology includes cell search, through which user terminals synchronize with base stations. Cell search allows the UE (User Equipment) and base station to achieve time and frequency synchronization and obtain system information broadcast by the base station to detect the PCI (Physical-layer Cell Identity). The system information broadcast by the base station includes the CP (Cyclic Prefix) mode.

[0038] In LTE technology, three physical layer signals or channels are specified for system synchronization: the primary synchronization signal (PSS), the secondary synchronization signal (SSS), and the physical broadcast channel (PBCH). The physical broadcast channel (PBCH) is not within the scope of this application and will not be discussed further here; however, please refer to existing technologies for details.

[0039] The PSS transmission period is 5ms, meaning the same signal is transmitted every 5ms. The SSS transmission period is 10ms, also transmitting the same signal every 10ms. However, each SSS includes two associated SSS signal sequences, with the first 5ms and the last 5ms transmitting different SSS signal sequences. Therefore, 5ms is half of the SSS signal. Consequently, the SSS signal sequence is also referred to as a half-frame sequence signal in this embodiment, where each SSS includes two half-frame sequence signals.

[0040] Each millisecond (ms) of PSS and SSS corresponds to one subframe. Both PSS and SSS have only one symbol, meaning that PSS carries information representing PSS only in the first subframe, while the first subframe of each half-frame sequence signal in SSS carries information representing SSS. For example, for SSS, there are 10 subframes within a 10ms period, counted from subframe 0 to subframe 9. Subframes 0 to 4 constitute the first half-frame sequence signal, and subframes 5 to 9 constitute the second half-frame sequence signal. Different SSS periods cycle, and information representing SSS is carried in subframes 0 and 5.

[0041] Both PSS and SSS occupy 62 subcarriers near the center subcarrier of the base station, meaning each subframe of PSS and SSS includes 62 subcarriers. The frequency domain sequence length of PSS and SSS is 62, occupying 62 consecutive 15KHz subcarriers near the center frequency of the LTE system, each occupying 1 OFDM (Orthogonal Frequency Division Multiplexing Symbol).

[0042] LTE technology specifies 504 unique physical layer cell identifiers, NCellID. NCellID is divided into two parts: NCellID = 3*NID1+NID2. NID2 is the physical layer cell group identifier ID indicated by the PSS, with a value ranging from 0 to 2. NID1 is the physical layer cell group identifier ID indicated by the SSS signal, with a value ranging from 0 to 167.

[0043] LTE also specifies duplex modes, including two modes: FDD (Frequency Division Duplex) and TDD (Time Division Duplex). The transmission timing of PSS and SSS is different in different duplex modes.

[0044] Please see Figure 1 , Figure 1 This is a timing diagram illustrating different duplex modes provided in an embodiment of this application. SSS and PSS record information in the signal using symbols. For SSS, each SSS period is 10ms, comprising 10 subframes. The SSS symbol only appears in subframe 0 or subframe 5, meaning the SSS information appears in the first subframe of the half-frame sequence signal. For PSS signals, the number of subframes between SSS information intervals varies depending on the duplex mode type.

[0045] For FDD, the PSS symbol is adjacent to the SSS symbol. For example... Figure 1 As shown, in FDD mode, the SSS symbol comes from subframe 5, and the PSS symbol is adjacent to the SSS in subframe 5.

[0046] In TDD duplex mode, the PSS symbol and SSS symbol are separated by two symbols, causing the PSS symbol and SSS symbol to be located in two adjacent subframes, such as subframe 1 and subframe 0, or subframe 5 and subframe 6 respectively. Figure 1 As shown, in TDD mode, the SSS symbol can still come from subframe 5, but after a two-symbol interval, the PSS symbol is located in subframe 6.

[0047] The user terminal first detects the Primary Synchronization Signal (PSS), and then further detects the Secondary Synchronization Signal (SSS) based on the PSS search results. Since the user terminal lacks base station synchronization information at the start of network searching, the PSS detection process includes, but is not limited to, detecting timing, frequency offset estimation, and NID2 during the primary synchronization signal transmission period. SSS detection also includes, but is not limited to, detecting timing, NID1, frequency offset, and cyclic prefix (CP) type.

[0048] The above description can be referenced from existing LTE technologies. The above is merely a brief explanation to facilitate understanding of this solution and should not be construed as a limitation of this application. Next, the auxiliary synchronization signal detection method based on complex-value combining provided in the embodiments of this application will be described in conjunction with LTE technology. Please refer to... Figure 2 , Figure 2 A flowchart illustrating a method for detecting auxiliary synchronization signals based on complex value combining, provided in an embodiment of this application. The method includes: S210, acquire the antenna data received by the antenna.

[0049] In the embodiments of this application, the antenna data is the data received by the antenna of various communication modules or communication devices, which includes the primary synchronization signal and the secondary synchronization signal.

[0050] In the embodiments of this application, when performing synchronization information detection, it is necessary to perform a conversion between the time and frequency domains. Since a subframe of the auxiliary synchronization signal includes 62 subcarriers, the sampling rate of the antenna data needs to be at least 0.96MHz.

[0051] S220 extracts the auxiliary synchronization signal from the antenna data.

[0052] The antenna data includes a primary synchronization signal and a secondary synchronization signal. When detecting the secondary synchronization signal, it is necessary to first extract the primary synchronization signal and the secondary synchronization signal in order to detect the synchronization information.

[0053] Please see Figure 3 , Figure 3 This is a schematic diagram of the equalization process of the auxiliary synchronization signal channel provided in an embodiment of this application.

[0054] In some embodiments of this application, extracting a secondary synchronization signal from antenna data may include: acquiring a primary synchronization signal and an initial secondary synchronization signal extracted from the antenna data; performing channel estimation on the primary synchronization signal to obtain a channel estimation value; and performing channel compensation on the initial secondary synchronization signal based on the channel estimation value to obtain the secondary synchronization signal.

[0055] In the embodiments of this application, the initial secondary synchronization signal is an unprocessed secondary synchronization signal directly extracted from the antenna data. Different secondary synchronization signals may be received by channels of different antennas, and the noise and fading introduced by different antennas are different. Different antenna channels will cause the secondary synchronization signals to be affected by the channel, thus making the actually received secondary synchronization signals different. However, in LTE, the secondary synchronization signals are specified to be transmitted periodically, therefore, all secondary synchronization signals are actually the same.

[0056] This application requires merging multiple secondary synchronization signals to average the signal variance and reduce the impact of noise. Due to actual reception reasons, the received secondary synchronization signals may be different. When the received initial secondary synchronization signals are different, they cannot be directly merged. Therefore, in the embodiments of this application, channel equalization (also known as channel compensation) processing can be performed on the initial secondary synchronization signals based on the primary synchronization signal to eliminate the influence of the channel, thereby making the information in each initial secondary synchronization signal consistent and thus enabling merging.

[0057] The extraction method of the primary synchronization signal can refer to existing technologies. In the embodiments of this application, the primary synchronization signal can be directly acquired, including but not limited to acquiring the position of the primary synchronization signal in the antenna data, time domain data, identification information NID2, and the local sequence of the primary synchronization signal. Specifically, when the sampling rate of the primary synchronization signal is 0.96MHz, the length of the local sequence of the primary synchronization signal is 64 sampling points. The PSS and SSS frequency domain sequences are 62 units long, occupying 62 consecutive 15kHz subcarriers near the center frequency of the LTE system, with each subcarrier spaced 15kHz apart.

[0058] For example, when detecting the primary synchronization signal, the time-domain data of the primary synchronization signal can be obtained from the antenna data function based on the position of the primary synchronization signal in the antenna data, and then the local sequence of the primary synchronization signal can be calculated based on the identification information NID2 of the primary synchronization signal. .

[0059] Similarly, the extraction method of the initial auxiliary synchronization signal can also refer to existing technologies, such as extracting the initial auxiliary synchronization signal based on the position of the auxiliary synchronization signal in the antenna data, which will not be elaborated on here.

[0060] In one embodiment of this application, channel estimation of the primary synchronization signal to obtain channel estimation values ​​may include: performing channel estimation on the data corresponding to each sampling point of the primary synchronization signal to obtain multiple original channel estimation values; calculating the power value corresponding to each original channel estimation value; and selecting the original channel estimation value whose power value is greater than a first preset power threshold from the multiple original channel estimation values ​​as the channel estimation value.

[0061] The main synchronization signal includes multiple sampling points and their corresponding data. As mentioned earlier, when the sampling rate of the main synchronization signal is 0.96MHz, the local sequence length of the main synchronization signal is 64 sampling points, and each sampling point corresponds to an original channel estimate.

[0062] For example, the process of channel estimation for the data corresponding to each sampling point of the master synchronization signal can be represented as:

[0063]

[0064] in, These are the original channel estimates, where i, j, and n are different index values ​​used to represent different sampling points. The local sequence of the main synchronization signal is calculated using the identification information NID2 of the main synchronization signal. The position of the main synchronization signal in the antenna data, where r is the received antenna data. The extracted master synchronization signal, To calculate the conjugate of a complex number.

[0065] The process of calculating the power value corresponding to each original channel estimate can be expressed as:

[0066] in, This is the power value. This is the original channel estimate.

[0067] The process of selecting a channel estimate with a power value greater than a first preset power threshold from multiple original channel estimates can be expressed as:

[0068] in, Indicates power value, For the determined channel estimate, This is the original channel estimate. This is the first preset power threshold. This is a configurable parameter, and its specific value can be determined based on a comprehensive evaluation of algorithm performance simulation and actual application performance. No specific restrictions are imposed here.

[0069] In some embodiments of this application, if there are multiple original channel estimates with power values ​​greater than the first preset power threshold, one can be arbitrarily selected, or further selected in other ways, such as selecting the largest original channel estimate, the original channel estimate closest to the mean, etc. The specific method can be configured according to the actual scenario and requirements, and is not limited here.

[0070] During signal transmission and reception, the signal travels through multiple paths to reach the receiving end. Different paths can have a certain impact on the signal. When the path power is low, it can cause significant noise interference to the signal. Therefore, in the embodiments of this application, the power value corresponding to each of the original channel estimates can be calculated. What is determined is the power corresponding to each path. The path with a power greater than a first preset power threshold is selected, and the original channel estimate corresponding to that path is used as the required channel estimate. This method can reduce or even eliminate the noise impact of the path on the master synchronization signal, thereby improving the accuracy of the determined channel estimate.

[0071] In embodiments of this application, channel compensation of the initial secondary synchronization signal based on the channel estimate may include: performing time-frequency domain conversion on the channel estimate and demapping it based on a preset signal resource mapping method to obtain a frequency domain estimate of the primary synchronization signal; acquiring the time domain data of the initial secondary synchronization signal under different cyclic prefix types based on a preset duplex mode; for each cyclic prefix type, performing FFT time-frequency domain conversion on the time domain data of the initial secondary synchronization signal corresponding to that cyclic prefix type and demapping it based on a preset signal resource mapping method to obtain the frequency domain data of the initial secondary synchronization signal; and performing channel compensation on the time domain data of the initial secondary synchronization signal based on the frequency domain estimate of the primary synchronization signal to obtain the secondary synchronization signal.

[0072] In the embodiments of this application, the primary synchronization signal and the initial secondary synchronization signal extracted from the antenna data are time-domain signals. Therefore, the channel estimate is a time-domain estimate, and the initial secondary synchronization signal is a time-domain signal. Thus, for the primary synchronization signal, the channel estimate needs to be converted between the time and frequency domains and demapped based on a preset signal resource mapping method to obtain the frequency-domain estimate of the primary synchronization signal. This process can be expressed as:

[0073] in, This is the channel estimate. The signal resource mapping method is defined by the LTE protocol, which maps the SSS signal to 62 subcarriers on either side of the center subcarrier. Demapping involves extracting these 62 subcarriers from the 64 subcarriers obtained by the FFT transform. The principles and methods of the signal resource mapping method can be found in existing technologies and will not be elaborated upon here.

[0074] Correspondingly, the initial secondary synchronization signal is also a time-domain signal and needs to be converted accordingly. Since the primary synchronization signal is deterministic, the various information of the secondary synchronization signal is still unknown at this time. Therefore, it is necessary to calculate the secondary synchronization signal under different possible conditions, such as different duplex modes and different cyclic prefix types.

[0075] The duplex mode can be detected at this stage. For example, the preset duplex mode is the duplex mode corresponding to the initial auxiliary synchronization signal. During the initial auxiliary synchronization signal detection stage, the duplex mode can be determined based on the received frequency point and frequency band. The acquisition of the duplex mode can refer to existing technologies, which will not be elaborated here.

[0076] Cyclic prefix types include two types: NCP (Normal Cyclic Prefix) and ECP (Extended Cyclic Prefix). During the initial detection of the auxiliary synchronization signal, the cyclic prefix type has not yet been determined. Therefore, it is necessary to make assumptions, obtain the time-domain data of the initial auxiliary synchronization signal under different cyclic prefix types, and perform time-frequency domain conversion and demapping.

[0077] Therefore, the processing of the initial auxiliary synchronization signal can be expressed as:

[0078]

[0079]

[0080]

[0081]

[0082] in, This is the initial auxiliary synchronization signal frequency domain data. The results are FFT (Fast Fourier Transform) transformations of the initial auxiliary synchronization signal. NCP and ECP represent different cyclic prefix types, and FDD and TDD represent different duplex modes. This is the difference between the positions of the initial auxiliary synchronization signal and the primary synchronization signal. This is the time-domain data of the initial auxiliary synchronization signal calculated based on the detected position of the primary synchronization signal; the remaining parameters are defined the same as above. Specifically, it is necessary to calculate the corresponding parameters for both ECP and NCP modes separately. , The frequency domain data of the auxiliary synchronization signal after channel compensation is represented by conj, which represents the calculation of the complex conjugate and is used for SSS channel compensation.

[0083] The specific principles and methods of channel compensation can be found in existing technologies, and will not be elaborated here.

[0084] In FDD mode, the PSS signal and SSS signal differ by one symbol, while in TDD mode they differ by three symbols. Given the speed requirements of LTE terminals, this time interval is less than the time-domain coherence time, indicating slow fading. Therefore, the channel estimate of the primary synchronization signal can be approximated as the channel estimate of the secondary synchronization signal. Thus, the channel estimate of the primary synchronization signal can be used for channel compensation of the initial secondary synchronization signal.

[0085] Different initial secondary synchronization signals may be received by channels of different antennas. Since different antennas experience different fading, the initial secondary synchronization signals are affected by the channel, potentially resulting in different received initial secondary synchronization signals. In the embodiments of this application, channel compensation is performed on the initial secondary synchronization signals to eliminate the influence of the channel, thereby ensuring consistency of information in each secondary synchronization signal and enabling subsequent merging.

[0086] Meanwhile, LTE's duplex mode specifies the position of the PSS symbol of an SSS symbol within its respective signal. If the sampling rate of the secondary synchronization signal and the primary synchronization signal is at its minimum value, i.e., 0.96MHz, then during time-frequency domain conversion, the sampling deviation between the PSS symbols of the SSS symbols may be non-integer, such as 0.5 or 1.5, resulting in a phase difference when equalizing the SSS signal using PSS channel estimation. To ensure an integer sampling deviation between the PSS symbols of the SSS symbols, it is usually necessary to increase the sampling rate, for example, to 1.92MHz.

[0087] This application compensates the initial auxiliary synchronization signal based on the primary synchronization signal, which can effectively reduce or avoid the influence of phase difference, and thus use the lowest sampling rate for signal sampling. Therefore, through channel compensation, this application can still use 0.96MHz for sampling, effectively reducing power consumption, computational complexity, and storage complexity.

[0088] In the embodiments of this application, after channel compensation is performed on the initial secondary synchronization signal based on the channel estimate to obtain the secondary synchronization signal, energy normalization processing can also be performed on the secondary synchronization signal based on a preset normalization method.

[0089] For example, energy normalization can be expressed as:

[0090] Where n represents the SSS signal index, This is the frequency domain data of the auxiliary synchronization signal after energy normalization. This is the frequency domain data of the auxiliary synchronization signal after channel compensation. This is the frequency domain data of the i-th auxiliary synchronization signal.

[0091] Different channels have different fading amplitudes when receiving signals, and the received gain may vary, resulting in different received secondary synchronization signals. LTE specifies that each secondary synchronization signal should be identical. Furthermore, in this embodiment, it is necessary to combine half-frame sequences of different secondary synchronization signals. Therefore, to avoid the impact of different received gains on the reception of secondary synchronization signals, energy normalization of the secondary synchronization signals is required to obtain more accurate signals and reduce the noise impact introduced by different channels. In other embodiments of this application, existing methods can be used to extract secondary synchronization signals from antenna data. In these embodiments, channel equalization / compensation of the secondary synchronization signals may not be based on the primary synchronization signal.

[0092] S230, demultiplex each half-frame sequence signal in the auxiliary synchronization signal to obtain the first descrambling sequence and the second descrambling sequence corresponding to each half-frame sequence signal.

[0093] In the embodiments of this application, each half-frame sequence signal is demultiplexed to split the half-frame sequence signal into odd subcarrier data and even subcarrier data, and then converted into m-sequences respectively to obtain a first descrambling sequence and a second descrambling sequence. That is, both the first descrambling sequence and the second descrambling sequence are m-sequences.

[0094] If the auxiliary synchronization signal has undergone energy normalization processing, then the different half-frame sequence signals in the auxiliary synchronization signal are demultiplexed respectively. This can be done by demultiplexing the different half-frame sequence signals in the auxiliary synchronization signal after energy normalization processing.

[0095] In the process of correlating the frequency domain data of the secondary synchronization signal, the computation is complex due to the large number of subcarriers in a single secondary synchronization signal frequency domain data. Therefore, it can be split into odd subcarrier data and even subcarrier data for separate calculation to reduce computational complexity and improve computational efficiency. Furthermore, this application converts it into an m-sequence, where the m-sequence can be transformed using the FMT transform to further improve computational efficiency.

[0096] Accordingly, in the embodiments of this application, demultiplexing each half-frame sequence signal in the auxiliary synchronization signal may include: obtaining the unique identifier information NID2 of the primary synchronization signal; for any half-frame sequence signal, splitting the half-frame sequence signal based on the parity of the carrier sequence number to obtain odd subcarrier data and even subcarrier data.

[0097] Furthermore, the even subcarrier data is descrambled based on NID2 and a preset first c sequence to obtain descrambled even subcarrier data; and the descrambled even subcarrier data is converted into an m sequence based on a preset m sequence conversion method to obtain a first descrambling sequence.

[0098] Furthermore, the odd subcarrier data is descrambled based on NID2, a preset second c sequence, and a z sequence to obtain descrambled odd subcarrier data; the descrambled odd subcarrier data is converted into an m sequence based on the preset m sequence conversion method to obtain a second descrambling sequence.

[0099] To facilitate understanding, the relationships between the main synchronization signal, the auxiliary synchronization signal, the C sequence, and the Z sequence will be explained first.

[0100] The master synchronization signal is generated by the z-sequence, also known as the ZC (Zadoff-Chu) sequence, which is a constant envelope zero autocorrelation sequence.

[0101] The frequency domain sequence of the master synchronization signal can be represented as:

[0102] Where n is the sequence index and j is the imaginary unit. The frequency domain order of the master synchronization signal is u, and the value of u corresponds to NID2. NID2 includes three values: 0, 1, and 2, which correspond to different u values. The correspondence can be as follows: when NID2 is 0, u is 25; when NID2 is 1, u is 29; when NID2 is 2, u is 34.

[0103] The secondary synchronization signal is generated from an m-sequence, which is a pseudo-random sequence generated by a linear feedback shift register. It is used to assist in cell search and downlink synchronization. The frequency domain sequence of the secondary synchronization signal can be represented as:

[0104]

[0105] in, and For the s sequence, and For a c sequence, and For the z-sequence, and These are the first descrambling sequence and the second descrambling sequence, respectively. and Subframes 0 and 5 are respectively. For an even number of subcarrier sequences, It is an odd-numbered subcarrier sequence.

[0106] In the above formula, and Calculated from NID1, the calculation method can be expressed as:

[0107]

[0108]

[0109] in, The identification information NID1, q and q for the auxiliary synchronization signal This is an intermediate calculation variable, and mod 31 is the modulo 31 operation.

[0110] In other embodiments of this application, a mapping table may also be used to record data. , The relationship with NID1. For example, the mapping table includes:

[0111] In the embodiments of this application, , and These are all cyclic shift sequences of m-sequences; for specific definitions, please refer to existing technologies.

[0112] For example, It can be represented as:

[0113]

[0114]

[0115] in Defined as:

[0116]

[0117] for It can be represented as:

[0118]

[0119]

[0120] in Defined as:

[0121] for It can be represented as:

[0122]

[0123]

[0124] in Defined as:

[0125] in, The identifier information NID2 for the master synchronization signal, where n and i are indices, where i is greater than 5. Let x be an m-sequence. and Referring to the foregoing, the s-sequence includes s0 and s1, where s0 is used for calculations on even subcarrier data and s1 is used for calculations on odd subcarrier data. Furthermore, c sequence includes and The z-sequence includes and .

[0126] This is the first c-sequence in the embodiments of this application. This is the second c sequence.

[0127] Please see Figure 4 , Figure 4 This is a schematic diagram of a demultiplexing process provided in an embodiment of this application. First, odd and even subcarrier data are obtained separately through demultiplexing. Combining the above-mentioned c sequence, the process of converting even subcarrier data into descrambled even subcarrier data can be represented as follows:

[0128]

[0129] in, For descrambling processing, For the first c sequence, and All data consists of descrambled even subcarrier data. Since the SSS signal includes 62 subcarrier data, only 31 even subcarrier data are present. However, when converting to an m-sequence, 32 numbers are needed; therefore, zeros need to be padded. Become .

[0130] Accordingly, the process of converting odd subcarrier data into descrambled odd subcarrier data can be represented as:

[0131]

[0132] in, For the second c sequence, Let z be the z-sequence and k be the index. Similarly, odd subcarrier data has only 31 subcarrier data. and All data consists of descrambled odd subcarrier data. When converting this to an m-sequence, 32 numbers are required; therefore, padding with zeros is necessary. Become The first c-sequence and the second c-sequence need to be calculated using NID2; therefore, it is necessary to obtain the NID2 obtained from the detection of the master synchronization signal.

[0133] In the embodiments of this application, the preset m-sequence transformation method can be FMT transformation, for example, using FHT (Fast Hadamard Transform) transformation in FMT, which can be expressed as:

[0134]

[0135] in, This is the first descrambling sequence. This is the second descrambling sequence. This is an FMT transform, specifically an FHT transform.

[0136] In this embodiment, on the one hand, the half-frame sequence signal is descrambled into even-subcarrier data and odd-subcarrier data. Based on this, the auxiliary synchronization signal can be combined once more, that is, the even-subcarrier data and odd-subcarrier data are combined, which helps to improve noise immunity. On the other hand, the even-subcarrier data and odd-subcarrier data are converted into m-sequences. The m-sequences can be calculated using FMT transform. Compared with other calculation methods, FMT calculation has lower computational complexity, which can improve computational efficiency and thus improve the detection efficiency of synchronization information.

[0137] S240, perform complex value merging on the first and second descrambling sequences of each half-frame sequence signal to obtain the intra-half-frame complex value merged sequence corresponding to each half-frame sequence signal.

[0138] Please see Figure 5 , Figure 5This is a schematic diagram illustrating the merging of a half-frame intra-complex value merging sequence according to an embodiment of this application. In the embodiments of this application, the first descrambling sequence and the second descrambling sequence can be merged by combining the NID2 of the auxiliary synchronization signal, wherein the second descrambling sequence includes multiple values. The mapping relationship between NID1 and the descrambling sequence can be referred to the aforementioned mapping table.

[0139] The signal received by the receiving device includes the accumulated transmitted signal and noise. When the noise increases beyond the single signal detection threshold, signal detection will fail. In LTE technology, the secondary synchronization signal transmitted multiple times in different cycles is the same. However, the transmission paths and reception channels of different secondary synchronization signals may differ, resulting in different levels of noise. Therefore, a method is needed to avoid detection failure due to noise and to minimize noise to improve detection accuracy.

[0140] Merging multiple signals can reduce signal variance and thus suppress the influence of noise. Therefore, in the embodiments of this application, half-frame sequence signals of auxiliary synchronization signals can be merged to reduce signal variance and suppress noise, thereby improving detection performance when performing synchronization information detection based on the merged signal.

[0141] Therefore, in the embodiments of this application, S240 and the subsequent S250 each perform a merging operation, but the objects they target for merging are different. In S240, the descrambled sequences are merged, while in S250, different half-frame sequence signals are merged.

[0142] In embodiments of this application, complex value merging can be the addition of two merging components. For example, for a half-frame sequence signal, the first descrambling sequence and the second descrambling sequence of the half-frame sequence signal are added together.

[0143] In some embodiments of this application, performing complex value merging on the first descrambling sequence and the second descrambling sequence of each half-frame sequence signal may include: exchanging the first descrambling sequence and the second descrambling sequence of each of the two half-frame sequence signals within the same auxiliary synchronization signal; for the two half-frame sequence signals within the same auxiliary synchronization signal, merging the first descrambling sequence and the second descrambling sequence after their exchange respectively to obtain the complex value merged sequence within the half-frame corresponding to each of the different half-frame sequence signals.

[0144] A secondary synchronization signal consists of 10ms, corresponding to 10 frames. Symbols containing information related to the secondary synchronization signal only appear in subframe 0 and subframe 5. During the detection phase, the frame timing of the secondary synchronization signal has not yet been determined. Therefore, it is not possible to determine whether the detected subframe is subframe 0 or subframe 5. Thus, the first and second descrambling sequences of subframe 0 and subframe 5 can be exchanged.

[0145] In the embodiments of this application, the first and second descrambling sequences of two half-frame sequence signals within the same auxiliary synchronization signal can be exchanged and then merged. This can help to further reduce the impact of noise caused by factors such as channel on the signal, facilitate the signal averaging method, and improve anti-scraping performance.

[0146] For example, swapping the first and second descrambling sequences of two half-frame sequence signals can be represented as follows:

[0147]

[0148] in, This represents the intra-half-frame complex value merge sequence corresponding to subframe 0. This represents the half-frame intra-complex value merge sequence corresponding to subframe 5. The calculation methods for m0 and m1 can be found in the aforementioned content and mapping table, and will not be repeated here.

[0149] S270, synchronization information detection is performed based on the intra-frame complex value merging sequence.

[0150] In the embodiments of this application, the complex-valued merged sequence within a half-frame can be detected to obtain synchronization information. This synchronization information includes, but is not limited to, the identifier information NID1 of the auxiliary synchronization signal, timing, cyclic prefix type, frequency offset, etc., and some existing methods can be used for detection.

[0151] In one embodiment of this application, before S270 performs synchronization information detection based on the intra-frame complex value merging sequence, the method may further include: S250, obtain the intra-frame complex value merged sequence corresponding to the half-frame sequence signal of each of the different auxiliary synchronization signals.

[0152] Among them, multiple auxiliary synchronization signals can be extracted from the antenna data. For each auxiliary synchronization signal, the intra-frame complex value merging sequence corresponding to the half-frame sequence signal of each auxiliary synchronization signal can be obtained through the aforementioned S230 and S240.

[0153] S260, perform complex value merging on the intra-half-frame complex value merging sequence corresponding to each half-frame sequence signal in different auxiliary synchronization signals to obtain the inter-half-frame complex value merging sequence.

[0154] Similarly, for the complex-valued merged sequences within each half-frame sequence signal, although the auxiliary synchronization signals of each period are the same, the two half-frame sequence signals within the same auxiliary synchronization signal are different. Therefore, when merging directly, the same half-frame sequence signals should be merged. For example, subframe 0 of multiple auxiliary synchronization signals should be merged with subframe 0, and subframe 5 should be merged with subframe 5.

[0155] Please see Figure 6 , Figure 6 This is a schematic diagram of the merging of a half-frame complex value merging sequence provided in an embodiment of this application.

[0156] During the detection phase, the frame timing has not yet been determined, and it is impossible to distinguish between subframe 0 and subframe 5. Therefore, in one embodiment of this application, the first half-frame sequence signal to be detected can be used as a reference to determine whether the subsequent half-frame sequence signals are the same as the first half-frame sequence signal, and then determine how to merge the half-frame sequence signals.

[0157] Accordingly, the intra-frame complex-valued merged sequences corresponding to each half-frame sequence signal in different auxiliary synchronization signals are combined using complex values ​​to obtain inter-frame complex-valued merged sequences, which may include: For each half-frame sequence signal, determine whether the half-frame sequence signal is the same as the first half-frame sequence signal determined from the antenna data, and generate half-frame difference indication information corresponding to the half-frame sequence signal. When the half-frame difference indication information indicates that the half-frame sequence signal is the same as the first half-frame sequence signal, the intra-half-frame complex value merging sequence of the half-frame sequence signal is merged with the historical inter-half-frame complex value merging sequence. The half-frame difference indication information indicates that when the half-frame sequence signal is different from the first half-frame sequence signal, the intra-half-frame complex value merging sequence of the two half-frame sequence signals in the auxiliary synchronization signal where the half-frame sequence signal is located is swapped and then merged with the historical inter-half-frame complex value merging sequence.

[0158] In this embodiment, the half-frame similarity / difference indication information is used to characterize whether the half-frame sequence signal is the same as the first half-frame sequence signal. There are various ways to determine whether they are the same, such as determining whether the signal features in the half-frame sequence signal are the same, or determining the duration of the interval between the half-frame sequence signal and the first half-frame sequence signal. The specific method is not limited here.

[0159] The historical half-frame inter-complex value merging sequence is obtained by merging multiple half-frame intra-complex value merging sequences. In other words, the historical half-frame inter-complex value merging sequence is the result of merging multiple half-frame intra-complex value merging sequences, and the historical half-frame inter-complex value merging sequence is also the previous half-frame inter-complex value merging sequence.

[0160] For example, the merging of half-frame inter-complex value merge sequences can be represented as: When the half-frame difference indicator information indicates that the half-frame sequence signal is the same as the first half-frame sequence signal:

[0161]

[0162] When the half-frame difference indicator information indicates that the half-frame sequence signal is different from the first frame half-frame sequence signal:

[0163]

[0164] The half-frame complex value merging sequence includes the half-frame complex value merging sequence of subframe 0 and the half-frame complex value merging sequence of subframe 5. Correspondingly, the historical half-frame complex value merging sequence includes the historical half-frame complex value merging sequence of subframe 0 and the historical half-frame complex value merging sequence of subframe 5. This represents the half-frame inter-frame complex value merge sequence of historical subframe 0. The historical half-frame inter-frame complex value merge sequence of subframe 5. This represents the half-frame inter-frame complex value merge sequence of historical subframe 0. The historical half-frame inter-frame complex value merge sequence of subframe 5. This represents the intra-frame complex value merged sequence of the current half-frame sequence signal subframe 0. This represents the intra-frame complex-valued merged sequence of the current half-frame sequence signal subframe 5, where w is the current count of the merging count, and W is the total number of merging counts. Other parameters not mentioned can be found in the preceding content.

[0165] In the embodiments of this application, merging half-frame sequence signals of different auxiliary synchronization signals helps to average the signal variance and reduce the impact of noise. Furthermore, the more auxiliary synchronization signals merged, the smaller the impact of noise and the higher the noise immunity. The number of auxiliary synchronization signals merged can be configured according to the actual scenario and is not limited here.

[0166] Accordingly, S270, performing synchronization information detection based on the intra-frame complex value merging sequence may also include: performing synchronization information detection on the inter-frame complex value merging sequence.

[0167] Please see Figure 7 , Figure 7 This is a schematic diagram illustrating synchronization information detection according to an embodiment of this application. In this embodiment, a corresponding detection method is also provided for detecting synchronization information in a half-frame complex-valued merged sequence. In this embodiment, detecting synchronization information in a half-frame complex-valued merged sequence may include: Calculate the power value corresponding to the inter-half-frame complex-valued merge sequence under each combination of various preset half-frame types and various preset CP types to obtain the target power group; search for the P power values ​​with the largest power from the target power group; if there is a power value among the P power values ​​that is greater than the second preset power threshold, then determine the synchronization information based on the peak power of the P power values. P is a positive integer, and the number can be configured according to the actual scenario.

[0168] During the detection phase, the half-frame type is determined by the half-frame sequence signal containing subframe 0 or subframe 5. Since the timing is not determined, the half-frame type of the half-frame sequence signal cannot be determined. Therefore, an assumption can be made about the half-frame type, and the power under different half-frame types can be calculated separately. Figure 7 The power calculation is shown below. Similarly, since the CP type has not yet been determined during the detection phase, it is also necessary to make assumptions about the CP type and perform calculations accordingly.

[0169] Correspondingly, the half-frame type and CP type can be combined into four cases, and the power corresponding to each combination can be calculated.

[0170] When CP type is assumed to be NCP, it can be represented as:

[0171]

[0172] When assuming the CP type is ECP, it can be represented as:

[0173]

[0174] Where s0 represents subframe 0 and s5 represents subframe 5. This represents the power value corresponding to the inter-frame complex-valued merge sequence in subframe 0 under NCP mode. This represents the power value corresponding to the inter-frame composite merge sequence in subframe 5 under NCP mode. This represents the power value corresponding to the inter-frame complex-combined sequence of subframe 0 in ECP mode. The power value corresponds to the inter-frame complex-valued merge sequence in subframe 5 under ECP mode, where W is the total number of merges. Other parameters not mentioned can be found in the preceding content.

[0175] Figure 7 Peak search involves searching for the P highest power values ​​from the target power set, which can be expressed as:

[0176] Figure 7 The corresponding peak search also includes determining, from P power values, a power value greater than the second preset power threshold, which can be expressed as:

[0177] Peak power determination includes determining synchronization information based on the peak power of P power values, including:

[0178]

[0179] in, The peak value corresponds to the half-frame sequence signal. The NID1 corresponding to this peak value is the NID1 of the auxiliary synchronization signal. The assumed half-frame type where the peak value is located is the half-frame type of the auxiliary synchronization signal. This indicates the CP type, which is the hypothetical CP type corresponding to the half-frame where the peak occurs. The second preset power threshold is the NID1 index corresponding to the P highest power values. This is a configurable parameter, and its specific value can be determined based on a comprehensive evaluation of algorithm performance simulation and actual application performance; no specific restrictions are imposed here. Other parameters not mentioned can be found in the preceding content.

[0180] Finally, it may also include frequency offset estimation, that is, calculating the frequency offset of the secondary synchronization signal, which can be expressed as:

[0181] in, For frequency offset, the other parameters are the same as above.

[0182] Please see Figure 8 and Figure 9 , Figure 8 This diagram illustrates the accuracy of auxiliary synchronization signal detection in an AWGN (Additive White Gaussian Noise) channel. Figure 8 This diagram illustrates the accuracy of secondary synchronization signal detection in a fading channel. The vertical axis represents Success Rate, and the horizontal axis represents SNR (Signal-to-Noise Ratio), with SNR measured in decibels (dB). CMB represents the number of combining operations, with a corresponding value of M.

[0183] For AWGN channels, in a non-merging scenario, the SSS detection success rate can reach 90% at a signal-to-noise ratio (SNR) of -5dB. With M=2 merging operations, the success rate can reach approximately 90% at an SNR of -8dB, representing a performance improvement of over 2dB. When M=8 merging operations, the success rate can reach approximately 90% at an SNR of -11dB. Therefore, if higher performance is required, the number of merging operations can be increased.

[0184] Please see Figure 9 For EUT70 (a type of fading channel), when the detection accuracy of SSS is the same, the more times the combining is performed, the lower the required signal-to-noise ratio becomes.

[0185] Based on the same inventive concept, this application also provides an auxiliary synchronization signal detection device based on complex value combining. Please refer to... Figure 10 , Figure 10This is a schematic diagram of a secondary synchronization signal detection device based on complex value combining according to an embodiment of this application. The secondary synchronization signal detection device 100 based on complex value combining includes: an acquisition unit 101, a channel equalization unit 102, a descrambling unit 103, a half-frame intra-complex value combining unit 104, and a detection unit 106.

[0186] Acquisition unit 101 is used to acquire antenna data received by the antenna.

[0187] The channel equalization unit 102 is used to extract auxiliary synchronization signals from the antenna data; there are at least two auxiliary synchronization signals, and each auxiliary synchronization signal includes two half-frame sequence signals.

[0188] The descrambling unit 103 is used to demultiplex each half-frame sequence signal in each of the auxiliary synchronization signals to obtain a first descrambling sequence and a second descrambling sequence corresponding to each of the different half-frame sequence signals; the first descrambling sequence and the second descrambling sequence include complex values ​​related to the unique signal identifier NID1 of the auxiliary synchronization signal.

[0189] The intra-frame complex value merging unit 104 is used to perform complex value merging on the first descrambling sequence and the second descrambling sequence of each half-frame sequence signal to obtain the intra-frame complex value merged sequence corresponding to each half-frame sequence signal; the complex value merging is used to merge the complex values ​​related to the NID1.

[0190] The detection unit 106 is used to detect synchronization information based on the intra-frame complex value merging sequence. It also performs synchronization information detection on the inter-frame complex value merging sequence.

[0191] In one embodiment, the acquisition unit 101 is used to acquire the primary synchronization signal and the initial secondary synchronization signal extracted from the antenna data; perform channel estimation on the primary synchronization signal to obtain a channel estimation value; and perform channel compensation on the initial secondary synchronization signal based on the channel estimation value to obtain the secondary synchronization signal.

[0192] In one embodiment, the acquisition unit 101 is used to perform energy normalization processing on the auxiliary synchronization signal based on a preset normalization method. Correspondingly, the descrambling unit is used to demultiplex different half-frame sequence signals in the auxiliary synchronization signal after the energy normalization processing.

[0193] In one embodiment, the acquisition unit 101 is used to perform channel estimation on the data corresponding to each sampling point of the main synchronization signal to obtain multiple original channel estimation values; the main synchronization signal includes multiple sampling points and their corresponding data, and each sampling point corresponds to one original channel estimation value; the power value corresponding to each original channel estimation value is calculated respectively; and the original channel estimation value with a power value greater than a first preset power threshold is selected from the multiple original channel estimation values ​​as the channel estimation value.

[0194] In one embodiment, the acquisition unit 101 is used to perform time-frequency domain conversion on the channel estimate and demap it based on a preset signal resource mapping method to obtain the frequency domain estimate of the primary synchronization signal; acquire the time domain data of the initial secondary synchronization signal under different cyclic prefix types based on a preset duplex mode; for each cyclic prefix type, perform FFT time-frequency domain conversion on the time domain data of the initial secondary synchronization signal corresponding to the cyclic prefix type and demap it based on the preset signal resource mapping method to obtain the frequency domain data of the initial secondary synchronization signal; and perform channel compensation on the time domain data of the initial secondary synchronization signal based on the frequency domain estimate of the primary synchronization signal to obtain the secondary synchronization signal.

[0195] In one embodiment, the descrambling unit 103 is used to obtain the unique identifier information NID2 of the main synchronization signal; for any half-frame sequence signal, the half-frame sequence signal is split into odd subcarrier data and even subcarrier data based on the parity of the carrier sequence number; the even subcarrier data is descrambled based on NID2 and a preset first c sequence to obtain descrambled even subcarrier data; the descrambled even subcarrier data is converted into an m sequence based on a preset m sequence conversion method to obtain the first descrambling sequence; the odd subcarrier data is descrambled based on NID2, a preset second c sequence and z sequence to obtain descrambled odd subcarrier data; the descrambled odd subcarrier data is converted into the m sequence based on the preset m sequence conversion method to obtain the second descrambling sequence.

[0196] In one embodiment, the intra-frame complex value merging unit 104 is used to exchange the first descrambling sequence and the second descrambling sequence of each of the two half-frame sequence signals within the same auxiliary synchronization signal; for the two half-frame sequence signals within the same auxiliary synchronization signal, the exchanged first descrambling sequence and the second descrambling sequence are merged respectively to obtain the intra-frame complex value merging sequence corresponding to each of the different half-frame sequence signals.

[0197] In one embodiment, the auxiliary synchronization signal detection device 100 based on complex value merging may further include: an inter-frame complex value merging module 105, configured to acquire the intra-frame complex value merging sequence corresponding to the respective half-frame sequence signal of different auxiliary synchronization signals, and perform complex value merging on the intra-frame complex value merging sequence corresponding to the respective half-frame sequence signal in the different auxiliary synchronization signals to obtain an inter-frame complex value merging sequence. Correspondingly, a detection unit 106 is configured to detect synchronization information on the inter-frame complex value merging sequence.

[0198] In one embodiment, the half-frame inter-complex value merging module 105 is used to determine whether each half-frame sequence signal is the same as the first half-frame sequence signal determined from the antenna data, and generate half-frame difference indication information corresponding to the half-frame sequence signal; the half-frame difference indication information indicates whether the half-frame sequence signal is the same as the first half-frame sequence signal; wherein, when the half-frame difference indication information indicates that the half-frame sequence signal is the same as the first half-frame sequence signal, the half-frame intra-complex value merging sequence of the half-frame sequence signal is merged with the historical half-frame inter-complex value merging sequence; the historical half-frame inter-complex value merging sequence includes those obtained by merging multiple half-frame intra-complex value merging sequences; when the half-frame difference indication information indicates that the half-frame sequence signal is not the same as the first half-frame sequence signal, the half-frame intra-complex value merging sequences of the two half-frame sequence signals in the auxiliary synchronization signal where the half-frame sequence signal is located are swapped and then merged with the historical half-frame inter-complex value merging sequence.

[0199] In one embodiment, the detection unit 106 is used to calculate the power value corresponding to the inter-frame complex value merging sequence under each combination of various preset half-frame types and various preset CP types to obtain a target power group; search for the P power values ​​with the largest power from the target power group; if there is a power value among the P power values ​​that is greater than a second preset power threshold, then determine the synchronization information based on the peak power of the P power values.

[0200] The function of the auxiliary synchronization signal detection device based on complex value merging is the same as that of the aforementioned auxiliary synchronization signal detection method based on complex value merging. For details, please refer to the previous text, and it will not be repeated here.

[0201] Based on the same inventive concept, embodiments of this application also provide a communication module for executing the auxiliary synchronization signal detection method based on complex value merging as provided in any of the foregoing embodiments.

[0202] In the embodiments of this application, the communication module can be any type of module used to implement LTE, such as a cellular communication module or an LTE modem. Specific structures can be found in existing technologies and will not be elaborated upon here.

[0203] Based on the same inventive concept, embodiments of this application also provide an electronic device, which may include the communication module provided in the foregoing embodiments or the communication module that performs the foregoing auxiliary synchronization signal detection method based on complex value merging.

[0204] In embodiments of this application, the electronic device may also include other structures, such as a processor and a memory, wherein the processor is connected to the memory.

[0205] In the embodiments of this application, the communication module and the processor in the electronic device can be integrated into the same chip or circuit board, or they can be independent devices.

[0206] In the embodiments of this application, the electronic device may be a computer, mobile phone, wearable device, server, vehicle terminal, home appliance, industrial control computer, etc.

[0207] Based on the same inventive concept, embodiments of this application also provide a computer-readable storage medium storing a program thereon, which, when run on a communication module, causes the communication module to execute the methods provided in the above embodiments.

[0208] The readable storage medium can be any available medium that the processor can access, or a data storage device such as a server or data center that integrates one or more available media. The available medium can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs (digital video discs)), or semiconductor media (e.g., SSDs (solid state disks)).

[0209] If the auxiliary synchronization signal detection method based on complex value merging is implemented as a software functional module and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause the communication module to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, ROM (Read-Only Memory), RAM (Random Access Memory), magnetic disks, or optical disks.

[0210] Based on the same inventive concept, this application also provides a computer program product, which includes a computer program that, when executed by a communication module, implements the method described above. The computer program product can be a software installation package, a program script, etc.

[0211] In the embodiments provided in this application, it should be understood that the disclosed methods and apparatus can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. The functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0212] The above embodiments can be freely combined without conflict, and the resulting embodiments are covered within the protection scope of this application.

[0213] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0214] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A method for detecting auxiliary synchronization signals based on complex-valued combining, characterized in that, include: Acquire antenna data received from the antenna. A secondary synchronization signal is extracted from the antenna data; the secondary synchronization signal comprises two half-frame sequence signals. Each half-frame sequence signal in the auxiliary synchronization signal is demultiplexed to obtain a first descrambling sequence and a second descrambling sequence corresponding to each of the different half-frame sequence signals; the first descrambling sequence and the second descrambling sequence include complex values ​​related to the unique signal identifier NID1 of the auxiliary synchronization signal. The first descrambling sequence and the second descrambling sequence of each half-frame sequence signal are combined using complex values ​​to obtain the intra-half-frame complex value combined sequence corresponding to each half-frame sequence signal. The complex value merging is used to merge complex values ​​associated with NID1; Synchronization information is detected based on the intra-frame complex value merging sequence.

2. The auxiliary synchronization signal detection method based on complex value merging according to claim 1, characterized in that, Extracting the secondary synchronization signal from the antenna data includes: Obtain the primary synchronization signal and initial secondary synchronization signal extracted from the antenna data; Channel estimation is performed on the primary synchronization signal to obtain the channel estimation value; Based on the channel estimate, channel compensation is performed on the initial secondary synchronization signal to obtain the secondary synchronization signal.

3. The auxiliary synchronization signal detection method based on complex value merging according to claim 2, characterized in that, After performing channel compensation on the initial secondary synchronization signal based on the channel estimate to obtain the secondary synchronization signal, the method further includes: The auxiliary synchronization signal is subjected to energy normalization processing based on a preset normalization method; The step of demultiplexing different half-frame sequence signals in the auxiliary synchronization signal includes: The different half-frame sequence signals in the auxiliary synchronization signal after the energy normalization process are demultiplexed respectively.

4. The auxiliary synchronization signal detection method based on complex value merging according to claim 2, characterized in that, The process of performing channel estimation on the primary synchronization signal to obtain a channel estimation value includes: Channel estimation is performed on the data corresponding to each sampling point of the main synchronization signal to obtain multiple original channel estimation values; the main synchronization signal includes multiple sampling points and their corresponding data, and each sampling point corresponds to one original channel estimation value; Calculate the power value corresponding to each of the original channel estimates; Select the original channel estimate whose power value is greater than a first preset power threshold from among the multiple original channel estimates, and use it as the channel estimate.

5. The auxiliary synchronization signal detection method based on complex value merging according to claim 4, characterized in that, The channel estimate is a time-domain estimate; the initial auxiliary synchronization signal is a time-domain signal. The channel compensation of the initial secondary synchronization signal based on the channel estimate includes: The channel estimate is converted to the time-frequency domain and demapped based on a preset signal resource mapping method to obtain the frequency domain estimate of the main synchronization signal. Based on the preset duplex mode, the time domain data of the initial auxiliary synchronization signal under different cyclic prefix types are obtained respectively. For each of the cyclic prefix types, the time-domain data of the initial auxiliary synchronization signal corresponding to the cyclic prefix type is subjected to FFT time-frequency domain transformation and demapping is performed based on a preset signal resource mapping method to obtain the frequency-domain data of the initial auxiliary synchronization signal. Channel compensation is performed on the time-domain data of the initial secondary synchronization signal based on the frequency domain estimate of the primary synchronization signal to obtain the secondary synchronization signal.

6. The auxiliary synchronization signal detection method based on complex value merging according to claim 2, characterized in that, The step of demultiplexing each of the half-frame sequence signals in the auxiliary synchronization signal to obtain the first descrambling sequence and the second descrambling sequence corresponding to each of the different half-frame sequence signals includes: Obtain the unique identifier information NID2 of the master synchronization signal; For any half-frame sequence signal, the half-frame sequence signal is split based on the parity of the carrier sequence number to obtain odd subcarrier data and even subcarrier data; The even subcarrier data is descrambled based on the NID2 and the preset first c sequence to obtain descrambled even subcarrier data; the descrambled even subcarrier data is converted into an m sequence based on a preset m sequence conversion method to obtain the first descrambling sequence; The odd subcarrier data is descrambled based on the NID2, the preset second c sequence, and the z sequence to obtain descrambled odd subcarrier data; the descrambled odd subcarrier data is converted into the m sequence based on the preset m sequence conversion method to obtain the second descrambling sequence.

7. The auxiliary synchronization signal detection method based on complex value combining according to claim 1, characterized in that, The complex value merging of the first descrambling sequence and the second descrambling sequence of each of the half-frame sequence signals includes: Exchange the first descrambling sequence and the second descrambling sequence of each of the two half-frame sequence signals within the same auxiliary synchronization signal; For two half-frame sequence signals within the same auxiliary synchronization signal, the first descrambling sequence and the second descrambling sequence after their respective exchanges are merged to obtain the intra-half-frame complex value merged sequence corresponding to each of the different half-frame sequence signals.

8. The auxiliary synchronization signal detection method based on complex value combining according to any one of claims 1-7, characterized in that, Before performing synchronization information detection on the intra-frame complex value merged sequence, the method further includes: Obtain the intra-frame complex-valued merged sequence corresponding to the half-frame sequence signal of each of the different auxiliary synchronization signals; The complex value merging is performed on the intra-half-frame complex value merging sequence corresponding to each of the half-frame sequence signals in the different auxiliary synchronization signals to obtain the inter-half-frame complex value merging sequence. The synchronization information detection based on the intra-frame complex value merging sequence includes: Synchronization information is detected in the half-frame inter-complex merged sequence.

9. The auxiliary synchronization signal detection method based on complex value merging according to claim 8, characterized in that, The step of performing complex value merging on the intra-frame complex value merging sequences corresponding to each of the different auxiliary synchronization signals to obtain inter-frame complex value merging sequences includes: For each half-frame sequence signal, it is determined whether the half-frame sequence signal is the same as the first half-frame sequence signal determined from the antenna data, and half-frame difference indication information corresponding to the half-frame sequence signal is generated; the half-frame difference indication information indicates whether the half-frame sequence signal is the same as the first half-frame sequence signal. Wherein, when the half-frame difference indication information indicates that the half-frame sequence signal is the same as the first half-frame sequence signal, the intra-half-frame complex value merging sequence of the half-frame sequence signal is merged with the historical inter-half-frame complex value merging sequence; the historical inter-half-frame complex value merging sequence includes those obtained by merging multiple intra-half-frame complex value merging sequences. The half-frame difference indication information indicates that when the half-frame sequence signal is different from the first half-frame sequence signal, the intra-half-frame complex value merging sequence of the two half-frame sequence signals in the auxiliary synchronization signal where the half-frame sequence signal is located is swapped and then merged with the historical inter-half-frame complex value merging sequence.

10. The auxiliary synchronization signal detection method based on complex value merging according to claim 8, characterized in that, The synchronization information detection of the half-frame complex-valued merged sequence includes: Calculate the power value corresponding to the inter-frame complex value merging sequence under each combination of various preset half-frame types and various preset CP types to obtain the target power group; Search for the P power values ​​with the highest power from the target power set; If any of the P power values ​​is greater than the second preset power threshold, then the synchronization information is determined based on the peak power of the P power values.

11. A device for detecting auxiliary synchronization signals based on complex-valued combining, characterized in that, include: The acquisition unit is used to acquire antenna data received by the antenna. A channel equalization unit is used to extract a secondary synchronization signal from the antenna data; the secondary synchronization signal includes two half-frame sequence signals. The descrambling unit is used to demultiplex each of the half-frame sequence signals in the auxiliary synchronization signal to obtain a first descrambling sequence and a second descrambling sequence corresponding to each of the different half-frame sequence signals; the first descrambling sequence and the second descrambling sequence include complex values ​​related to the unique signal identifier NID1 of the auxiliary synchronization signal. The intra-frame complex value merging unit is used to perform complex value merging on the first descrambling sequence and the second descrambling sequence of each half-frame sequence signal to obtain the intra-frame complex value merged sequence corresponding to each half-frame sequence signal. The complex value merging is used to merge complex values ​​associated with NID1; The detection unit is used to detect synchronization information based on the intra-frame complex value merging sequence.

12. A communication module, characterized in that, Used to perform the auxiliary synchronization signal detection method based on complex value merging as described in any one of claims 1-10.

13. An electronic device, characterized in that, include: A communication module, the communication module being used to execute the auxiliary synchronization signal detection method based on complex value merging as described in any one of claims 1-10.

14. A readable storage medium, characterized in that, include: The readable storage medium stores a program that, when executed by the communication module, causes the communication module to implement the auxiliary synchronization signal detection method based on complex value merging as described in any one of claims 1-10.

15. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by the communication module, implements the auxiliary synchronization signal detection method based on complex value merging as described in any one of claims 1-10.

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