Ad hoc network physical layer frame structure and wireless communication method

Abstract

The application provides a wireless communication method and device based on a predetermined physical layer frame structure, the method comprising: framing by a sending end based on information to be sent according to a predetermined physical layer frame structure, combining data scrambling, channel interleaving and modulation processing to generate a target data frame; wherein the sending end is any node sending target information in an ad hoc network; the predetermined physical layer frame structure comprises a preamble part, and the preamble part comprises a PB0 part and a PB1 part; receiving the target data frame by a receiving end, and parsing the target data frame to obtain the PB0 part and the PB1 part of the preamble part in the target data frame; estimating the frequency offset of the target data frame and correcting by the receiving end based on the PB0 part; completing fast synchronization of the target data frame based on the PB1 part, and obtaining the information to be sent by combining demodulation and decoding processing. The design of the physical layer frame structure can reduce the transmission delay of the ad hoc network device and reduce the sensitivity of the system to the Doppler shift.

Description

Technical Field

[0001] This invention relates to the field of computer technology, and in particular to a self-organizing network physical layer frame structure and wireless communication method. Background Technology

[0002] Ad hoc networks are a networking form distinct from common cellular networks. They are decentralized and can form their own networks with little or no configuration of devices other than communication nodes, thus enabling multi-hop communication between any two points in the network.

[0003] Currently, there are two main types of frame structures for the physical layer of ad hoc networks: one is the physical layer frame structure based on the CSMA protocol, which generally needs to consider retransmissions caused by collisions, and the frame field contains retransmission feedback and other content; the other is the physical layer frame structure based on the TDMA protocol, which does not need to consider collisions, and generally divides the radio frame into several time slots, using the time slots as scheduling objects, and the frame field contains synchronization, verification and other content.

[0004] The physical layer frame structure of the current CSMA self-organizing network protocol suffers from collisions and low transmission efficiency when the number of nodes is large. The physical layer frame structure of the TDMA self-organizing network protocol is cumbersome in its networking process, takes too long, and suffers from severe Doppler shift, which affects the construction speed and network performance of the self-organizing network. Summary of the Invention

[0005] This invention provides a physical layer frame structure and wireless communication method for ad hoc networks to address the shortcomings of low transmission efficiency and severe Doppler shift in existing ad hoc network technologies. By optimizing the physical layer frame structure, especially the preamble, high-precision frequency offset estimation and fast synchronization of single-carrier frequency domain equalization are achieved, thereby reducing transmission latency of ad hoc network devices and reducing the system's sensitivity to Doppler shift.

[0006] This invention provides a wireless communication method based on a predetermined physical layer frame structure, comprising:

[0007] The transmitting end assembles the data according to a predetermined physical layer frame structure based on the information to be transmitted, and generates the target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the transmitting end is any node in the ad hoc network that transmits the target information; the predetermined physical layer frame structure includes a preamble, which includes a PB0 part and a PB1 part, used to complete synchronization and frequency offset correction;

[0008] The receiving end receives the target data frame and parses the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame;

[0009] The receiving end estimates and corrects the frequency offset of the target data frame based on the PB0 part; based on the PB1 part, it completes the fast synchronization of the target data frame, and obtains the information to be transmitted by combining demodulation and decoding processing.

[0010] According to the wireless communication method based on a predetermined physical layer frame structure provided by the present invention, the PB0 part includes a UW sequence and a modulation sequence for frequency offset correction; the PB1 part includes a cyclic prefix (CP) sequence, a unique code (UW-L) sequence, and a cyclic suffix (CP) sequence for synchronization.

[0011] According to the wireless communication method based on a predetermined physical layer frame structure provided by the present invention, the UW sequence includes 20 UW sequences, and the modulation sequence includes 16 modulation symbols, wherein...

[0012] The first 16 of the 20 UW sequences are used for frame arrival detection (PD) and coarse frequency synchronization (CFE), while the last 4 of the 20 UW sequences are used for frame coarse timing synchronization detection (CTE).

[0013] The first three of the 16 modulation symbols are empty symbols; the last 13 of the 16 modulation symbols are a BAKER sequence, used to achieve precise timing synchronization FTE.

[0014] According to the wireless communication method based on a predetermined physical layer frame structure provided by the present invention, the UW sequence in the PB0 part includes 20 UW sequences, wherein the first 16 UW sequences of the 20 UW sequences are long UW words, and the last 4 UW sequences of the 20 UW sequences are short UW words.

[0015] Correspondingly,

[0016] The step of estimating and correcting the frequency offset of the target data frame based on the PB0 portion includes:

[0017] Based on the PB0 part, a coarse frequency offset estimation is first performed using a short UW word, and then a fine frequency offset estimation is performed using a long UW word. Based on the estimation results, the frequency offset of the target data frame is corrected.

[0018] According to the wireless communication method based on a predetermined physical layer frame structure provided by the present invention, the step of completing the fast synchronization of the target data frame based on the PB1 portion includes:

[0019] Based on the PB1 part, combined with the time-frequency synchronization algorithms Schmidl and Cox, the target data frame is quickly synchronized.

[0020] According to the wireless communication method based on a predetermined physical layer frame structure provided by the present invention, the channel interleaving includes two-level interleaving, intra-block interleaving, and subframe interleaving.

[0021] According to the wireless communication method based on a predetermined physical layer frame structure provided by the present invention, the modulation processing includes quadrature phase shift keying (QPSK) and 16 quadrature amplitude phase modulation (16QAM).

[0022] The present invention also provides a wireless communication device based on a predetermined physical layer frame structure, comprising:

[0023] The transmitting module is used by the transmitting end to frame the information to be transmitted according to a predetermined physical layer frame structure, and generate a target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the transmitting end is any node in the ad hoc network that transmits target information; the predetermined physical layer frame structure includes a preamble, and the preamble includes a PB0 part and a PB1 part;

[0024] The receiving and parsing module is used to receive the target data frame from the receiving end and parse the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame;

[0025] The estimation output module is used by the receiving end to estimate and correct the frequency offset of the target data frame based on the PB0 part; and to complete the fast synchronization of the target data frame based on the PB1 part, and to obtain the information to be transmitted by combining demodulation and decoding processing.

[0026] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the wireless communication method based on a predetermined physical layer frame structure as described in any of the preceding claims.

[0027] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the wireless communication method based on a predetermined physical layer frame structure as described in any of the preceding claims.

[0028] This invention provides a wireless communication method, apparatus, electronic device, and storage medium based on a predetermined physical layer frame structure. The method involves a transmitting end framing information to be transmitted according to the predetermined physical layer frame structure, combined with data scrambling, channel interleaving, and modulation processing to generate a target data frame. The transmitting end can be any node in an ad hoc network transmitting target information. The predetermined physical layer frame structure includes a preamble, comprising PB0 and PB1 portions for synchronization and frequency offset correction. A receiving end receives the target data frame and parses it to obtain the PB0 and PB1 portions of the preamble. Based on the PB0 portion, the receiving end estimates and corrects the frequency offset of the target data frame. Based on the PB1 portion, the receiving end performs rapid synchronization of the target data frame, and combined with demodulation and decoding processing, obtains the information to be transmitted. This invention optimizes the physical layer frame structure, especially the preamble, to achieve high-precision frequency offset estimation and rapid synchronization with single-carrier frequency domain equalization, thereby reducing transmission latency and the system's sensitivity to Doppler shift in ad hoc network devices. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a flowchart illustrating the wireless communication method based on a predetermined physical layer frame structure provided by the present invention.

[0031] Figure 2 This is a schematic diagram of the predetermined physical layer frame structure provided by the present invention;

[0032] Figure 3 This is a schematic diagram of the structure of the wireless communication device based on a predetermined physical layer frame structure provided by the present invention.

[0033] Figure 4 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0035] The following is combined with Figures 1-4 The present invention describes a wireless communication method, apparatus, electronic device, and storage medium based on a predetermined physical layer frame structure.

[0036] Figure 1 This is a flowchart illustrating the wireless communication method based on a predetermined physical layer frame structure provided by the present invention. Figure 2 This is a schematic diagram of the predetermined physical layer frame structure provided by the present invention, as shown below. Figure 1 and Figure 2 As shown, in one specific embodiment, the present invention provides a wireless communication method based on a predetermined physical layer frame structure, comprising:

[0037] Step S110: The transmitting end assembles the data according to the predetermined physical layer frame structure based on the information to be transmitted, and generates the target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the transmitting end is any node in the ad hoc network that transmits the target information; the predetermined physical layer frame structure includes a preamble, and the preamble includes a PB0 part and a PB1 part;

[0038] Step S120: The receiving end receives the target data frame and parses the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame;

[0039] Step S130: The receiving end estimates and corrects the frequency offset of the target data frame based on the PB0 part; based on the PB1 part, it completes the fast synchronization of the target data frame, and obtains the information to be transmitted by combining demodulation and decoding processing.

[0040] Furthermore, the PB0 part includes a UW sequence and a modulation sequence for frequency offset correction; the PB1 part includes a cyclic prefix (CP) sequence, a unique code (UW-L) sequence, and a cyclic suffix (CP) sequence for synchronization.

[0041] Furthermore, the UW sequence comprises 20 UW sequences, and the modulation sequence comprises 16 modulation symbols, wherein,

[0042] The first 16 of the 20 UW sequences are used for frame arrival detection (PD) and coarse frequency synchronization (CFE), while the last 4 of the 20 UW sequences are used for frame coarse timing synchronization detection (CTE).

[0043] The first three of the 16 modulation symbols are empty symbols; the last 13 of the 16 modulation symbols are a BAKER sequence, used to achieve precise timing synchronization FTE.

[0044] Furthermore, the UW sequence in the PB0 part includes 20 UW sequences, wherein the first 16 UW sequences are long UW words and the last 4 UW sequences are short UW words.

[0045] Correspondingly,

[0046] The step of estimating and correcting the frequency offset of the target data frame based on the PB0 portion includes:

[0047] Based on the PB0 part, a coarse frequency offset estimation is first performed using a short UW word, and then a fine frequency offset estimation is performed using a long UW word. Based on the estimation results, the frequency offset of the target data frame is corrected.

[0048] Furthermore, the step of achieving rapid synchronization of the target data frame based on the PB1 portion includes:

[0049] Based on the PB1 part, combined with the time-frequency synchronization algorithms Schmidl and Cox, the target data frame is quickly synchronized.

[0050] Furthermore, the channel interleaving includes two-level interleaving, intra-block interleaving, and subframe interleaving.

[0051] Furthermore, the modulation process includes quadrature phase shift keying (QPSK) and 16 quadrature amplitude-phase modulation (16QAM).

[0052] In this embodiment, the waveform burst structure used in the physical layer frame is for TDD duplex mode, comprising automatic gain control, a preamble section consisting of PB0 and PB1, a data block section, and a guard interval. The preamble section is responsible for fast automatic gain control, signal arrival detection, channel frequency error correction, timing error correction, phase error correction, and channel frequency response estimation for each frame of data. The preamble in this scheme uses a method that enables microsecond-level automatic gain control convergence and fast synchronization without a phase-locked loop.

[0053] In addition, to adapt to TDD duplex mode, a two-layer frame structure design is adopted: physical frames and physical subframes. A physical frame consists of one physical downlink subframe and N uplink subframes (N≤4). The physical subframe consists of the following parts: a preamble (PB0, PB1) for synchronization, frequency offset correction, and channel equalization; an MB sequence for transmitting relevant control information (FCH); and a DB sequence for transmitting the payload. The number of payload data blocks is variable and can be selected from the following values: 6, 12, 24, 48, 96. When there are 6 data blocks, the frame length is 298µs under a 16M symbol rate. After PB0 processing, the data block boundaries must be accurately synchronized, while the timing and frequency errors are within acceptable ranges for subsequent processing. PB0 includes three parts: the first 16 UW sequences perform frame arrival detection (PD) and coarse frequency synchronization (CFE), and the last 4 UW sequences perform frame coarse timing synchronization detection (CTE) to ensure that the synchronization error is less than one symbol period. Of the 16 modulation symbols, the first three are empty symbols, which are filled in, and the last 13 are BAKER sequences to achieve fine timing synchronization (FTE). The PB1 sequence is used for fine frequency offset (FFE) and fine timing (FTE) estimation, as well as for channel estimation before equalization. The sequence consists of three parts: CP, UW_L, and CP, where CP is the cyclic redundancy prefix and UW_L is the unique code.

[0054] In this embodiment, the transmitting end assembles the target data frame based on the information to be transmitted according to a predetermined physical layer frame structure. This is combined with data scrambling, channel interleaving including two-level interleaving, intra-block interleaving, and subframe interleaving, and modulation processing including quadrature phase shift keying (QPSK) and 16-QAM (16-quadrature amplitude phase modulation) to generate the target data frame. The transmitting end is any node in the ad hoc network that transmits the target information. The predetermined physical layer frame structure includes a preamble, which comprises PB0 and PB1 parts. The receiving end receives the target data frame and parses it to obtain the PB0 and PB1 parts of the preamble. Based on the PB0 part, the receiving end estimates and corrects the frequency offset of the target data frame. Based on the PB1 part, it uses the Schmidl and Cox time-frequency synchronization algorithms to achieve fast synchronization of the target data frame. Demodulation and decoding are then combined to obtain the information to be transmitted. Specifically, high-precision frequency offset estimation includes the following: Since simple carrier frequency offset causes signal rotation and amplitude attenuation, for a single-carrier frequency domain equalization (SC-FDE) system, when a block of SC-FDE is transformed to the frequency domain via FFT, the frequency deviation will cause inter-carrier interference (ICI) at each frequency point. This not only cannot be canceled by a single-tap frequency domain equalizer, but also introduces additional errors during equalization. After the frequency domain signal is not fully compensated, it is then passed through IFFT, resulting in an additional interference caused by estimation errors, in addition to the interference caused by the frequency offset. However, this additional interference is spread out by the IFFT transform and averaged across each symbol, causing a much smaller impact than on OFDM. However, if the frequency offset is not compensated, it will significantly affect the block synchronization algorithm and timing algorithm. Therefore, frequency offset estimation and compensation are required for the received signal. The symmetry between repeating small blocks A (A being the training sequence) in the preamble can be used to estimate the frequency offset, as shown in the following algorithm:

[0055]

[0056] Δf = angle(P(d)) / (2πLT)

[0057] Where P(d) represents the correlation between the two parts of the training symbol data; R1 represents the first half of the received sequence training symbol data. R1 is the conjugate transpose of R1; R2 is the latter half of the received sequence training symbol data; d is the timing bias to be estimated; k is the k-th point of the received sequence training symbol data; L0 is the sum of the training symbol length and the cyclic prefix length; L is the length of the cyclic prefix; r() is the expression for a point in the received sequence training symbol data; r *() is the conjugate expression of a certain point of the training symbol data of the received sequence; Δf is the frequency offset estimation range; angle() is the angle value of the correlation function; T is the symbol period.

[0058] It should be noted that the above symbols have the same meaning when they appear in other formulas of this application, and will not be elaborated here.

[0059] The frequency offset estimation range, accuracy are related to L0 and L. Generally, the smaller L is, the larger the estimation range is, and the lower the estimation accuracy is. Sometimes, in order to increase the capture range without reducing the estimation accuracy, the influence of noise on the algorithm can be reduced by increasing L0. In practical applications, when the signal-to-noise ratio is not very small, generally L0 = L.

[0060] Due to the deviation of the crystal oscillator itself, a large frequency offset will occur during the down-conversion process. For the SC-FDE broadband wireless communication system, when the carrier frequency fc = 2GHz, the deviation d of the general crystal oscillator is 25ppm, and the maximum frequency offset of the system is 80kHz. We need to ensure that fast fading does not occur during the processing of one symbol (data block), so the selected data block length is not too long, so a relatively large frequency offset can be estimated. Since the frequency offset range is related to the length L of the UW word, first use a short UW word for a rough frequency offset estimation, and then use a long UW word for a fine frequency offset estimation. The simulation results show that for the case of a small frequency offset, actually only one frequency offset estimation using the long UW is required. The frequency offset estimation range in the frequency offset estimation range relational formula is [-F / 2L, F / 2L], and the actual maximum frequency offset is 2d*fc. It is necessary to satisfy F / 2L > 2d*fc, that is, fc / F < 1 / (4dL) = 10e4 / L, then L < F*10e4 / fc. When F / fc is too small, it will cause L to be too small and the frequency offset estimation accuracy to decrease. However, for the rough frequency offset estimation, the main purpose is to roughly capture the frequency offset, and the improvement of accuracy is completed after block synchronization and timing synchronization.

[0061] In this embodiment, regarding fast synchronization: The estimation algorithm using the training symbol mainly utilizes the symmetric characteristics of the training symbol to perform sliding correlation on the signal. The training symbol adopts the training symbol structure in the time offset estimation algorithm proposed by Schmidl and Cox for time-frequency synchronization, that is, the first and second parts are the same [+A, +A], and the data part excluding the CP has good autocorrelation. A still uses the Chu sequence format. Let the entire symbol length be N and the CP length be L. The correlation between the first and second parts of the training symbol data and the received sequence r(n) is expressed as:

[0062]

[0063] And,

[0064]

[0065] definition:

[0066]

[0067] For the signal energy of the second part of the received training symbols, the timing measure is defined as:

[0068]

[0069] Under multiple sampling conditions, if a symbol has m sampling points and the length of A is L symbols, the correction formula is:

[0070]

[0071] As can be seen from the relevant principles, the moment corresponding to the maximum value of the timing measure is the moment of the first sample value of the SC-FDE symbol, indicating the start of transmission, that is:

[0072]

[0073] In this embodiment, the data scrambling generator polynomial in the data scrambling design is:

[0074] f(x) = 1 + x 14 +x 15

[0075] The initialization state is configurable. The scrambler initializes once at the start of each physical subframe. The scrambler only scrambles the payload data.

[0076] In this embodiment, the channel interleaving design employs two-level interleaving, intra-block interleaving, and subframe interleaving. First, based on the modulation scheme (QPSK, 16QAM), the coded output bitstream undergoes serial-to-parallel conversion (N:1). When using QPSK modulation, N=2; when using 16QAM modulation, N=4. Thus, after serial-to-parallel conversion, each data block contains 224 symbols.

[0077] In this embodiment, the modulation scheme and baseband waveform use both QPSK and 16QAM symbol mapping methods, and the baseband shaping adopts root-raised cosine shaping. ALPHA is specified as 0.25. The symbol rate supports 4MHz, 8MHz, and 16MHz, with a roll-off factor of 0.25, therefore the corresponding channel bandwidths of the system are 5MHz, 10MHz, and 20MHz.

[0078] The wireless communication method based on a predetermined physical layer frame structure provided in this embodiment describes the specific transmission process of the target data frame generated by framing according to the predetermined physical layer frame structure, as well as the specific calculation process during the transmission process. This achieves high-precision frequency offset estimation and fast synchronization of single-carrier frequency domain equalization, thereby reducing the transmission latency of self-organizing network devices and reducing the system's sensitivity to Doppler frequency shift.

[0079] The present invention provides a wireless communication device based on a predetermined physical layer frame structure. The wireless communication device based on the predetermined physical layer frame structure described below and the wireless communication method based on the predetermined physical layer frame structure described above can be referred to in correspondence.

[0080] Figure 3 This is a schematic diagram of the structure of the wireless communication device based on a predetermined physical layer frame structure provided by the present invention, as shown below. Figure 3 As shown, in one specific embodiment, the wireless communication device based on a predetermined physical layer frame structure provided by the present invention includes:

[0081] The transmitting module 310 is used by the transmitting end to frame the information to be transmitted according to a predetermined physical layer frame structure, and generate a target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the transmitting end is any node in the ad hoc network that transmits target information; the predetermined physical layer frame structure includes a preamble, and the preamble includes a PB0 part and a PB1 part;

[0082] The receiving and parsing module 320 is used to receive the target data frame from the receiving end and parse the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame;

[0083] The estimation output module 330 is used by the receiving end to estimate and correct the frequency offset of the target data frame based on the PB0 part; and to complete the fast synchronization of the target data frame based on the PB1 part, and to obtain the information to be transmitted by combining demodulation and decoding processing.

[0084] The wireless communication device based on the above-mentioned self-organizing network physical layer frame structure provided in this embodiment, by setting up a transmitting module, a receiving parsing module, and an estimation output module, specifically describes the specific transmission process of the target data frame generated by framing according to the predetermined physical layer frame structure, as well as the specific calculation process during the transmission process. It realizes high-precision frequency offset estimation and fast synchronization of single-carrier frequency domain equalization, thereby reducing the transmission delay of self-organizing network devices and reducing the system's sensitivity to Doppler frequency shift.

[0085] Figure 4 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 4As shown, the electronic device may include: a processor 410, a communications interface 420, a memory 430, and a communication bus 440, wherein the processor 410, the communications interface 420, and the memory 430 communicate with each other via the communication bus 440. The processor 410 can call logical instructions in the memory 430 to execute a wireless communication method based on the aforementioned ad hoc network physical layer frame structure, the method including:

[0086] The sending end assembles the data according to a predetermined physical layer frame structure based on the information to be transmitted, and generates the target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the sending end is any node in the ad hoc network that transmits the target information; the predetermined physical layer frame structure includes a preamble, which includes a PB0 part and a PB1 part;

[0087] The receiving end receives the target data frame and parses the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame;

[0088] The receiving end estimates and corrects the frequency offset of the target data frame based on the PB0 part; based on the PB1 part, it completes the fast synchronization of the target data frame, and obtains the information to be transmitted by combining demodulation and decoding processing.

[0089] Furthermore, the logical instructions in the aforementioned memory 430 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, 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 computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0090] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the wireless communication method based on the aforementioned ad hoc network physical layer frame structure provided by the methods described above, the method comprising:

[0091] The sending end assembles the data according to a predetermined physical layer frame structure based on the information to be transmitted, and generates the target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the sending end is any node in the ad hoc network that transmits the target information; the predetermined physical layer frame structure includes a preamble, which includes a PB0 part and a PB1 part;

[0092] The receiving end receives the target data frame and parses the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame;

[0093] The receiving end estimates and corrects the frequency offset of the target data frame based on the PB0 part; based on the PB1 part, it completes the fast synchronization of the target data frame, and obtains the information to be transmitted by combining demodulation and decoding processing.

[0094] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0095] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wireless communication method based on a predetermined physical layer frame structure, characterized in that, include: The transmitting end assembles the data according to a predetermined physical layer frame structure based on the information to be transmitted, and generates the target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the transmitting end is any node in the ad hoc network that transmits the target information; the predetermined physical layer frame structure includes a preamble, which includes a PB0 part and a PB1 part, used to complete synchronization and frequency offset correction; The receiving end receives the target data frame and parses the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame; The receiving end estimates and corrects the frequency offset of the target data frame based on the PB0 part; based on the PB1 part, it completes the fast synchronization of the target data frame, and obtains the information to be transmitted by combining demodulation and decoding processes. The PB0 part includes a UW sequence and a modulation sequence, used to complete frequency offset correction; the PB1 part includes a cyclic prefix CP sequence, a unique code UW-L sequence, and a cyclic suffix CP sequence, used to complete synchronization. The UW sequence comprises 20 UW sequences, and the modulation sequence comprises 16 modulation symbols. The first 16 UW sequences are used for frame arrival detection (PD) and coarse frequency synchronization (CFE), while the last 4 UW sequences are used for frame coarse timing synchronization detection (CTE). The first 3 of the 16 modulation symbols are empty symbols, and the last 13 of the 16 modulation symbols are a BAKER sequence used to achieve fine timing synchronization (FTE). The step of achieving fast synchronization of the target data frame based on the PB1 part includes: achieving fast synchronization of the target data frame based on the PB1 part, combined with the time-frequency synchronization algorithms Schmidl and Cox. The channel interleaving includes two-level interleaving, intra-block interleaving, and subframe interleaving; The PB1 sequence is used for both fine frequency offset FFE and fine timing FTE estimation, as well as for channel estimation before equalization. The PB1 sequence includes three parts: CP, UW_L, and CP, where CP is the cyclic redundancy prefix and UW_L is the unique code. The UW sequence in the PB0 part includes 20 UW sequences, wherein the first 16 UW sequences are long UW words and the last 4 UW sequences are short UW words. Correspondingly, The step of estimating and correcting the frequency offset of the target data frame based on the PB0 part includes: first, using a short UW word to perform a coarse frequency offset estimation based on the PB0 part, then using a long UW word to perform a fine frequency offset estimation, and correcting the frequency offset of the target data frame based on the estimation results. The algorithm for frequency offset estimation using UW words is as follows: ； ； in, To train the correlation between the two parts of the symbolic data; To receive the first half of the sequence training symbol data, for The conjugate transpose of; To receive the latter half of the sequence training symbol data; The timing deviation to be estimated; For receiving the sequence training symbol data, the first point; The sum of training symbol length and cyclic prefix length; The length of the cyclic prefix; An expression for a point in the received sequence training symbol data; This is the conjugate expression for a point in the received sequence training symbol data; This is the range for frequency offset estimation; The angle value of the relevant function; The symbol period.

2. The wireless communication method based on a predetermined physical layer frame structure according to claim 1, characterized in that, The modulation process includes quadrature phase shift keying (QPSK) and 16 quadrature amplitude-phase modulation (16QAM).

3. A wireless communication device based on a predetermined physical layer frame structure, characterized in that, include: The transmitting module is used by the transmitting end to frame the information to be transmitted according to a predetermined physical layer frame structure, and generate a target data frame by combining data scrambling, channel interleaving and modulation processing; wherein, the transmitting end is any node in the ad hoc network that transmits target information; the predetermined physical layer frame structure includes a preamble, and the preamble includes a PB0 part and a PB1 part; The receiving and parsing module is used to receive the target data frame from the receiving end and parse the target data frame to obtain the PB0 part and PB1 part of the preamble in the target data frame; The estimation output module is used by the receiving end to estimate and correct the frequency offset of the target data frame based on the PB0 part; and to complete the fast synchronization of the target data frame based on the PB1 part, and to obtain the information to be transmitted by combining demodulation and decoding processing. The PB0 part includes a UW sequence and a modulation sequence, used to complete frequency offset correction; the PB1 part includes a cyclic prefix CP sequence, a unique code UW-L sequence, and a cyclic suffix CP sequence, used to complete synchronization. The UW sequence comprises 20 UW sequences, and the modulation sequence comprises 16 modulation symbols. The first 16 UW sequences are used for frame arrival detection (PD) and coarse frequency synchronization (CFE), while the last 4 UW sequences are used for frame coarse timing synchronization detection (CTE). The first 3 of the 16 modulation symbols are empty symbols, and the last 13 of the 16 modulation symbols are a BAKER sequence used to achieve fine timing synchronization (FTE). The step of achieving fast synchronization of the target data frame based on the PB1 part includes: achieving fast synchronization of the target data frame based on the PB1 part, combined with the time-frequency synchronization algorithms Schmidl and Cox. The channel interleaving includes two-level interleaving, intra-block interleaving, and subframe interleaving; The PB1 sequence is used for both fine frequency offset FFE and fine timing FTE estimation, as well as for channel estimation before equalization. The PB1 sequence includes three parts: CP, UW_L, and CP, where CP is the cyclic redundancy prefix and UW_L is the unique code. The UW sequence in the PB0 part includes 20 UW sequences, wherein the first 16 UW sequences are long UW words and the last 4 UW sequences are short UW words. Correspondingly, The step of estimating and correcting the frequency offset of the target data frame based on the PB0 portion includes: Based on the PB0 part, a coarse frequency offset estimation is first performed using a short UW word, and then a fine frequency offset estimation is performed using a long UW word. Based on the estimation results, the frequency offset of the target data frame is corrected. The algorithm for frequency offset estimation using UW words is as follows: ； ； in, To train the correlation between the two parts of the symbolic data; To receive the first half of the sequence training symbol data, for The conjugate transpose of; To receive the latter half of the sequence training symbol data; The timing deviation to be estimated; For receiving the sequence training symbol data, the first point; The sum of training symbol length and cyclic prefix length; The length of the cyclic prefix; An expression for a point in the received sequence training symbol data; This is the conjugate expression for a point in the received sequence training symbol data; This is the range for frequency offset estimation; The angle value of the relevant function; The symbol period.

4. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the wireless communication method based on a predetermined physical layer frame structure as described in any one of claims 1 to 2.

5. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the wireless communication method based on a predetermined physical layer frame structure as described in any one of claims 1 to 2.

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