Physical channel resource mapping method for PDSCH (Physical Downlink Shared Channel) of power wireless private network

Abstract

The invention relates to a physical channel resource mapping method for a PDSCH (physical downlink shared channel) of a power wireless private network, which belongs to the technical field of wireless communication, and comprises the following steps of: redesigning resource mapping of mapping a 5GNR PDSCH to the power wireless private network according to an OFDM (orthogonal frequency division multiplexing) symbol and subcarrier distribution mode in a standard 5GNR PDSCH to form a power wireless private network resource grid, and remapping discrete PDSCH resource blocks to form a power wireless private network resource grid; corresponding timing synchronization, frequency synchronization and channel estimation and equalization methods are provided, the requirement that 5GNR PDSCH resources can be transmitted in a power wireless private network is met, and the spectrum utilization efficiency and the system anti-interference capacity are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of wireless communications and relates to a method for mapping physical channel resources of a PDSCH in a power wireless private network. Background Art

[0002] Discrete shared frequency bands (223-235MHz) are widely used in communication networks for industries such as electricity, gas, and civil air defense, mainly deploying LTE 230 and IoT 230 communication systems. In 2018, it was allowed to integrate discrete frequency points in the 223-226MHz and 229-233MHz bands to support data transmission of multiple services through time / frequency division multiplexing. However, compared with traditional mobile communication bands, the technical deployment of this band faces the following challenges:

[0003] 1. Bandwidth limitation and spectrum distribution discreteness

[0004] The total bandwidth of the 230MHz band is only about 10MHz, and the sub-band width is limited (25kHz), the sub-band intervals are far apart, and the resource distribution is highly discrete. This limits the communication capacity and increases the complexity of multi-carrier signal design. At the same time, industry shared use increases the risk of non-stationary interference.

[0005] 2. Incompatible with the fifth generation new wireless (abbreviated as: 5GNR) frame structure

[0006] The 5GNR frame structure is designed for continuous bandwidth in the mid- and high-frequency bands, with a subcarrier spacing of 15kHz or its integer multiples, while the resource block bandwidth of the 230MHz band is 25kHz, which does not match. In addition, the continuous spectrum assumption of 5G is not applicable to discrete spectrum scenarios, and traditional scheduling algorithms are difficult to apply directly.

[0007] 3. Spectrum interference complexity

[0008] There are various complex interferences in the shared environment, such as Chirp Signal (Chirp) and Frequency Shift Keying (FSK) signals, which will significantly affect the demodulation performance of PDSCH, especially in the case of low signal-to-noise ratio.

[0009] The main function of 5GNR PDSCH (Physical Downlink Shared Channel) is to carry the transmission channel of terminal user (UE) data. It is the key channel for delivering actual content to users. However, the deployment of 5GNR PDSCH in resource grids still faces technical challenges:

[0010] First: PDSCH mapping requirements

[0011] PDSCH (Physical Downlink Shared Channel) is the main physical channel responsible for user data transmission in 5GNR (New Radio). It is used to carry all user data and some control signaling from the base station (gNB) to the user equipment (UE) in the downlink. In the traditional 5GNR frequency band, PDSCH occupies continuous subcarrier resources. However, in the 230MHz frequency band, due to the discontinuity of spectrum bandwidth and resource distribution, PDSCH cannot be directly mapped to the 230MHz frequency band of continuous subcarriers. Secondly, the power industry's private network communication has high reliability requirements. When mapping resources, the interference caused by other systems in the shared frequency band must be considered to ensure that the terminal correctly demodulates PDSCH.

[0012] Second: The impact of timing deviation on PDSCH demodulation

[0013] In the power wireless private network resource grid, the impact of timing deviation on PDSCH demodulation is particularly significant. Due to the discrete spectrum distribution and narrow bandwidth of the power wireless private network frequency band (such as 230MHz), the accuracy of timing synchronization becomes more important. In this resource grid, timing deviation will cause the starting position of the OFDM symbol to be out of sync with the FFT window, destroying the orthogonality between subcarriers, and then causing inter-symbol interference (ISI) and inter-subcarrier interference (ICI). Specifically, the mapping method of PDSCH needs to adapt to the discreteness of the spectrum, and any timing offset will lead to increased interference between different subbands, further affecting the signal demodulation performance. In addition, due to the large number of subcarriers in this resource grid, the impact of timing deviation on the data phase rotation on the subcarrier is more obvious, thereby changing the shape of the constellation diagram and increasing the bit error rate. In the power wireless private network environment, if the timing deviation exceeds the length of the cyclic prefix (CP), it will not only cause intra-symbol interference, but also may introduce the information of the next symbol into the received signal of the current symbol. Given the stringent application requirements of power wireless private networks (such as low latency and high reliability), precise timing synchronization is critical to ensuring the integrity and demodulation performance of PDSCH signals.

[0014] Third: The impact of frequency deviation on PDSCH demodulation

[0015] Frequency deviation has a significant impact on the demodulation of PDSCH mapped to the power wireless private network resource grid. Since the power wireless private network resource grid has the characteristics of discrete spectrum distribution, frequency deviation (carrier frequency offset, CFO) will cause each subcarrier of the received signal to deviate from its ideal frequency, resulting in phase rotation in the frequency domain. This offset will further amplify the orthogonality destruction between subcarriers in the resource grid, resulting in inter-subcarrier interference (ICI) and inter-symbol interference (ISI). The bandwidth and subband spacing of resource blocks in the power wireless private network are narrow and discrete, making the interference caused by frequency deviation more complex and significant. Specifically, the discrete resource distribution may cause interference to spread to multiple subbands, further deteriorating the demodulation performance and significantly reducing the signal-to-noise ratio (SNR) of the signal. Frequency deviation may also cause interference superposition between different subbands, making it more difficult to distinguish signals and resulting in an increase in bit error rate. In extreme cases, frequency deviation may make it difficult to distinguish between signals and noise, directly affecting the effective transmission of PDSCH. Therefore, in the power wireless private network resource grid, accurate frequency synchronization is crucial to ensure PDSCH demodulation performance and is one of the key technologies to ensure communication reliability and data transmission quality.

[0016] Fourth: The impact of channel estimation and equalization on PDSCH demodulation

[0017] Channel estimation and equalization are key steps in the PDSCH demodulation process in the power wireless private network resource grid, and have a direct impact on the demodulation performance. In the power wireless private network, due to the discrete spectrum resources and narrow bandwidth, the accuracy of channel estimation is particularly important because it determines whether the impact of the wireless channel on the transmission signal can be effectively compensated. In this specific resource grid structure, PDSCH still uses demodulation reference signals (DMRS) similar to those in 5GNR for channel estimation to help demodulate the physical channel. However, due to the discreteness of spectrum distribution and the unevenness of subband spacing in the power wireless private network, traditional channel estimation methods may not be fully adapted to the new resource grid structure. If the channel estimation is inaccurate, the quality of the demodulated signal will be significantly reduced, which is manifested as an increase in inter-symbol interference (ISI) and inter-carrier interference (ICI), thereby increasing the bit error rate. Channel equalization is a further compensation step for the channel estimation result, which helps to recover the signal after channel fading and interference. If the channel equalization fails to fully take into account the discrete spectrum characteristics of the power private network, these interferences may not be effectively suppressed, thereby affecting the reliability of data transmission and communication quality. Therefore, in the power wireless private network resource grid, accurate channel estimation and equalization are key factors to ensure PDSCH demodulation performance.

[0018] In general, deploying 5GNR PDSCH in the power wireless private network requires redesigning the PDSCH mapping rules to solve the problem of discontinuous spectrum resources, and designing suitable synchronization solutions and channel estimation and equalization solutions for the remapped PDSCH time-frequency resources. Summary of the invention

[0019] In view of this, an object of the present invention is to provide a method for mapping physical channel resources of a PDSCH in a power wireless private network.

[0020] In order to achieve the above object, the present invention provides the following technical solutions:

[0021] A method for mapping PDSCH physical channel resources in a power wireless private network includes the following steps:

[0022] Process 1: PDSCH channel encoding and decoding and resource mapping process: At the transmitting end, the PDSCH channel is encoded into a 5GNR PDSCH resource block, and then the 5GNR PDSCH resource block is discretely mapped to the 230MHz wireless resource to form a discrete power wireless private network 230MHz PDSCH resource block; at the receiving end, the discrete power wireless private network 230MHz PDSCH resource block is restored to a standard 5GNR PDSCH resource, and the 5GNR PDSCH link is used for demodulation to obtain the transmitted PDSCH data block;

[0023] Process 2: Timing synchronization process: retain the demodulation reference signal in the 230MHz PDSCH resource block, set all its data parts to zero, and form a received reference signal data block; use the demodulation reference signal in the local PDSCH, and use the method of mapping the demodulation reference signal at the transmitting end to map it to the power wireless private network resource grid to form a local reference signal data block; then perform conjugate point multiplication of the received reference signal data block and the local reference signal data block, and perform sum calculation in the frequency domain to obtain the demodulation reference signal frequency domain correlation array, perform inverse fast Fourier transform IFFT on the array to the time domain impact array, and find the position of the maximum value, which is the timing synchronization position;

[0024] Process 3: Frequency synchronization process: First, the phase difference between the received and local reference signal data blocks is calculated respectively, and the magnitude of the frequency offset is estimated by using the phase difference of adjacent demodulation reference signals to complete frequency synchronization;

[0025] Process 4: Channel estimation and equalization process: The 230MHz PDSCH resource block in the power wireless private network resource grid is first divided into multiple 230MHz PDSCH sub-resource blocks; each 230MHz PDSCH sub-resource block uses the least squares method to minimize the error calculation channel matrix and noise variance based on the local demodulation reference signal; then the minimum mean square error MMSE is used to calculate the equalizer weight matrix, and the received signal is input into the equalizer to complete the equalization. Finally, all the 230MHz PDSCH sub-resource block equalization results are spliced ​​into a complete 5GNR PDSCH modulation data block.

[0026] Further, the PDSCH channel coding and decoding and resource mapping process includes:

[0027] Step A1: Scramble, code block segment, LDPC encode, rate match and modulate the PDSCH data block to form a 5GNR PDSCH modulated data block, which is then mapped together with the demodulation reference signal to form a standard 5GNR PDSCH resource block;

[0028] Step A2: Map the standard 5GNR PDSCH resource block to the power wireless private network resource grid to form a 230MHz PDSCH resource block, where the power wireless private network resource grid is 4096×20, indicating 4096 subcarriers and 20 orthogonal frequency division multiplexing (OFDM) symbols; the power wireless private network resource grid can carry 5GNR PDSCH resource blocks of multiple terminals at the same time, and these resource blocks occupy different subcarriers and OFDM symbols in the power wireless private network resource grid;

[0029] Step A3: The standard 5GNR PDSCH resource block occupies the time-frequency resources with the physical resource block PRB as the smallest unit. Each PRB contains 12 consecutive subcarriers, in which the demodulation reference signal is embedded. The time-frequency resource grid of the power wireless private network is a discretely distributed subcarrier resource, and there is a non-continuous characteristic between its subcarrier resource blocks. The 5GNR PDSCH resource block is remapped to adapt to the power wireless private network resource grid;

[0030] Step A4: Map the standard 5GNR PDSCH resource block to the power wireless private network resource grid, occupy 12N subcarriers continuously in the frequency domain; occupy the same number of OFDM symbols continuously in the time domain, and finally map the standard 5GNR PDSCH resource block to a 230MHz PDSCH resource block; the power wireless private network resource grid is modulated by OFDM to obtain the power wireless private network frame data;

[0031] Step A5: At the receiving end, the received power wireless private network frame data is subjected to interference filtering and OFDM demodulation is performed to obtain the power wireless private network resource grid. According to the standard 5GNR PDSCH resource block mapping rule of the transmitting end, the 230MHz PDSCH resource block is taken out from the power wireless private network resource grid and remapped to obtain the 5GNR PDSCH resource block, which includes data and demodulation reference signals. The demodulation reference signal is used to perform timing synchronization, frequency synchronization, channel estimation and equalization to obtain the PDSCH modulated data block, and then the standard 5GNR PDSCH channel decoding process is performed to obtain the transmitted PDSCH data block.

[0032] Furthermore, the received power wireless private network frame data in step A5 is subjected to interference filtering, which uses a notch filter to filter out the interference subband in the 230MHz PDSCH resource block. The specific processing is as follows:

[0033] The received signal is input into the notch filter to filter out the frequency band corresponding to the interference signal. In the notch filter, the amplitude gain of the notch frequency band is 0, and the amplitude gain of other frequency bands is 1. The transfer function of the notch filter is:

[0034]

[0035] Furthermore, the timing synchronization process specifically includes the following steps:

[0036] Step B1: remap the demodulation reference signal in the local standard 5GNR PDSCH resource block to the power wireless private network resource grid, which only carries the local demodulation reference signal, and all other time-frequency resources are set to zero to form a local reference signal data block; receive the time domain signal waveform at the receiving end, perform OFDM demodulation on it, and obtain the power wireless private network resource grid, in which only the demodulation reference signal corresponding to the 5GNR PDSCH is retained, and other parts are set to zero to form a received reference signal data block;

[0037] Step B2: Perform conjugate point multiplication calculation on the local reference signal data block and the received reference signal data block, and accumulate the conjugate point multiplication results of the corresponding subcarrier positions in the frequency domain to obtain the reference signal frequency domain correlation array; perform fast Fourier transform on the array to obtain the time domain impact array, and find the position of the maximum value as the timing synchronization position, that is, the timing synchronization point d of the power wireless private network frame data. The calculation process is:

[0038]

[0039]

[0040] in,() *represents complex conjugate operation; max() represents the maximum value in the array; abs() represents modulo calculation; N represents the number of reference signal OFDM symbols; rx_dmrs(n) represents the received reference signal data block; pdsch_dmrs_s(n) represents the local reference signal data block; IFFT represents the inverse fast Fourier transform; pdsch_dmrs_C(d) represents the correlation value at d timing offsets, where d is the position deviation between the received and local reference signal data blocks;

[0041] Step B3: Compensate the received signal according to the timing synchronization position d. The calculation process is:

[0042] rx_TimeSync_waveform(n)=rx_waveform(n+d),n=0,...,N-1

[0043] Among them, rx_waveform represents the received power wireless private network frame data; rx_TimeSync_waveform represents the power wireless private network frame data after timing precision synchronization.

[0044] Further, the frequency synchronization process includes the following steps:

[0045] Step C1: At the receiving end, the power wireless private network frame data rx_TimeSync_waveform after timing compensation is demodulated through OFDM to obtain the power wireless private network resource grid; according to the corresponding position of the 230MHz PDSCH resource block in the power wireless private network, the reference signal data on each OFDM is taken out to form the received reference signal data, which is recorded as rx_dmrs_data[m][n], where the subscript m represents the number of the reference signal on the carrier, and n represents the number on the OFDM symbol;

[0046] Step C2: According to the rule for generating a 5GNR PDSCH demodulation reference signal at the transmitting end, the same 5GNR PDSCH demodulation reference signal is generated at the receiving end to form local reference signal data, recorded as tx_dmrs_data[m][n], where the subscript m represents the number of the reference signal on the carrier, and n represents the number on the OFDM symbol;

[0047] Step C3: Conjugate point multiplication is performed on the received reference signal data rx_dmrs_data[m][n] and the local reference signal data tx_dmrs_data[m][n] to obtain the received and local reference signal phase difference matrix, recorded as dmrs_phaseDifference[m][n], and the calculation formula is:

[0048] dmrs_phaseDifference[m][n]=angle(rx_dmrs_data[m][n]·(tx_dmrs_data[m][n]) * )

[0049] Where: · represents dot product; () * Indicates conjugate calculation; angle() means taking the phase angle of all members;

[0050] Step C4: The reference signal phase difference matrix dmrs_phaseDifference[m][n] is averaged in the frequency domain to obtain the reference signal phase difference array:

[0051]

[0052] Where: "M" indicates the number of subcarriers occupied by the reference signal;

[0053] Step C5: Assuming the reference signal phase difference array dmrs_phaseAvgDifference[n], calculate the average value Δθ of the phase differences between adjacent reference signals. The calculation formula is:

[0054]

[0055] Where: “l” represents the number of OFDMs carrying reference signals;

[0056] Step C6: Calculate the frequency deviation according to the phase difference Δθ caused by the two adjacent reference signals during the transmission process, and then perform frequency deviation compensation on the power wireless private network frame data rx_TimeSync_waveform to obtain the power wireless private network frame data rx_fine_waveform(n). The calculation formula is:

[0057]

[0058] Wherein: Δf is the frequency deviation value; T is the time interval between two reference signals.

[0059] Furthermore, the channel estimation and equalization process specifically includes the following steps:

[0060] Step D1: The receiving end receives the time domain signal waveform, recorded as rx_waveform(n), and after timing and frequency adjustment, recorded as rx_fine_waveform(n), performs OFDM demodulation on the signal to obtain the power wireless private network resource grid; according to the 230MHz PDSCH resource block mapping rule, the spectrum of the power wireless private network resource grid occupied by the 230MHz PDSCH is non-continuously distributed;

[0061] Step D2: taking a 230 MHz PDSCH resource block from the power wireless private network resource grid, dividing the 230 MHz PDSCH resource block into a plurality of 230 MHz PDSCH sub-resource blocks, and defining a 230 MHz PDSCH resource occupying consecutive subcarriers as a sub-resource block;

[0062] Step D3: Assume that the reference channel and data in a 230MHz PDSCH sub-resource block are rx_fine_dmrs and rx_fine_data respectively. The demodulation reference signal of the local 5GNR PDSCH of this sub-block is recorded as tx_dmrs_data, which is used for least squares channel estimation. The calculation process is:

[0063] H LS =(X H X) -1 X H Y=X -1 Y

[0064] The corresponding LS channel estimation on each subcarrier is expressed as:

[0065]

[0066] Wherein, X[k] is the local reference signal tx_dmrs_data; Y[k] is the received reference signal rx_fine_dmrs; k is the subcarrier number; N is the number of demodulation reference signals in each OFDM symbol;

[0067] Step D4: Channel estimation result H of 230MHz PDSCH sub-resource block LS [k], k=0,1,...,N-1, in the frequency domain, it is a discrete non-continuous state, and the linear interpolation method is used. The calculation process is:

[0068]

[0069] Among them, H[k j ] is the interpolated channel estimate, k j Located in k a With k b Between; H LS [k a ] and H LS [k b ] is the known value of LS channel estimation;

[0070] Step D5: Using the channel estimation matrix H, adopt the MMSE equalizer weight matrix After completing channel equalization on the received signal rx_fine_data, the PDSCH sub-block data is obtained. The calculation process is:

[0071]

[0072] X[k]=W[k]Y[k],k=0,1,...,N-1

[0073] Among them, X[k] is the PDSCH sub-block data after equalization; Y[k] is the PDSCH sub-block data rx_fine_data before equalization; N is the PDSCH sub-block data size; express

[0074] Step D6: Using the same principle, all 230MHz PDSCH sub-resource blocks in the 230MHz PDSCH resource block are channel estimated and equalized, and the data in all PDSCH sub-resource blocks are equalized and spliced ​​into a complete 5G NRPDSCH data block, and finally the 5G NR channel decoding process is performed.

[0075] The beneficial effects of the present invention are:

[0076] Aiming at the special needs of 5GNR PDSCH deployed in power wireless private network, the present invention proposes a wireless resource allocation method for 5GNR PDSCH adapted to power wireless private network. According to the allocation mode of OFDM symbols and subcarriers in standard 5GNR PDSCH, the resource mapping of 5GNR PDSCH to power wireless private network is redesigned to form power wireless private network resource grid, and corresponding timing synchronization, frequency synchronization, channel estimation and equalization methods are proposed for the discrete PDSCH resource blocks after remapping, so as to meet the requirements of 5GNR PDSCH resources being able to be transmitted in power wireless private network, and improve the spectrum utilization efficiency and system anti-interference ability. The specific advantages are as follows:

[0077] First: The present invention proposes an adaptation scheme for 5GNR PDSCH time-frequency resources and electric wireless private network time-frequency resources. In the time domain, the 5GNR PDSCH time domain resource grid uses a time slot (14 OFDM symbols) as the largest unit, and the electric wireless private network time domain resource grid is composed of 20 OFDM symbols. When mapping the 5GNR PDSCH time domain resources, a power wireless private network frame is selected for mapping. In the frequency domain, the 5GNR PDSCH resource uses a PRB (12 consecutive subcarriers) as the smallest unit. When mapping the frequency domain resources, 12K times (K is a positive integer) of consecutive subcarrier positions in the electric wireless private network are selected. There may be unusable 25KHz sub-bands in the 12 integer multiples of the subcarrier interval.

[0078] Second: The present invention proposes a timing precision synchronization scheme for the PDSCH of the power wireless private network. The standard 5GNR PDSCH resources are mapped to the 230MHz frequency band to form a 230MHz PDSCH resource block. Although the 230MHz PDSCH resource block occupies a discrete state of 12 integer multiples of the subcarrier in the frequency domain, the method provided by the present invention is used to recombine the demodulation reference signal in the discrete 230MHz PDSCH, and still obtain a perfect precision synchronization solution.

[0079] Third: The present invention proposes a frequency precision synchronization scheme for the PDSCH of the power wireless private network. The standard 5GNR PDSCH resources are mapped to the 230MHz frequency band to form a 230MHz PDSCH resource block. At the receiving end, the demodulation reference signal is taken out from the 230MHz PDSCH resource block, and the phase difference between two adjacent OFDM symbols is calculated. At the same time, the local demodulation reference signal and the phase difference between two adjacent OFDM symbols are used to perform frequency precision synchronization calculation.

[0080] Fourth: The present invention provides a channel estimation and equalization solution for the PDSCH of the electric power wireless private network. The receiving end uses the 230MHz PDSCH resource block. Since the frequency domain resources support the existence of discontinuous characteristics, during channel estimation and equalization, the 230MHz PDSCH resource block is first divided into multiple small PDSCH resource blocks. These PDSCH resource blocks occupy subcarriers in a continuous state and are an integer multiple of 12. Then each block completes channel estimation and equalization independently. This suppresses the performance loss caused by the discontinuous subcarrier occupation of the 230MHz PDSCH.

[0081] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0083] Figure 1 This is a diagram of the transmission process of 5GNR PDSCH in the power wireless private network;

[0084] Figure 2 This is a diagram of the PDSCH channel encoding, decoding and resource mapping process;

[0085] Figure 3 To synchronize timing and adjust the flow chart;

[0086] Figure 4 It is the frequency precision synchronization and adjustment flow chart;

[0087] Figure 5 It is a diagram of the channel estimation and channel equalization process of PDSCH;

[0088] Figure 6 It is the simulation and verification block diagram of PDSCH receiving and transmitting links;

[0089] Figure 7 It is the time-frequency resource diagram for sending and receiving PDSCH under CDL channel, where (a) is the discrete time-frequency resource diagram of the transmitting end (txAnt1); (b) is the discrete time-frequency resource diagram of the transmitting end (txAnt2); (c) is the discrete time-frequency resource diagram of the receiving end (txAnt1); (d) is the discrete time-frequency resource diagram of the receiving end (txAnt2);

[0090] Figure 8 Schematic diagram of the power wireless private network resource grid remapping for 5GNR PDSCH resource blocks;

[0091] Fig. 9 (a) to (l) are the time domain diagrams of transmission and reception and subcarrier occupancy corresponding to antenna 1 and antenna 2 when the signal-to-noise ratio is 0 dB;

[0092] Fig.10 Schematic diagram of remapping the time and frequency resources of the power wireless private network into 5GNR PDSCH resource blocks;

[0093] Fig.11 Timing and frequency synchronization tracking performance with a timing offset of 107 and a frequency offset of 100 Hz are set for simulation, where (a) is frequency synchronization and (b) is timing synchronization;

[0094] Fig.12 : It is the PDSCH channel equalization performance diagram, where (a) is the constellation diagram corresponding to QPSK at the receiving end (txAnt1); (b) is the constellation diagram corresponding to QPSK after equalization at the receiving end (txAnt1); (c) is the constellation diagram corresponding to QPSK at the receiving end (txAnt2); (d) is the constellation diagram corresponding to QPSK after equalization at the receiving end (txAnt2); (e) is the bit log-likelihood ratio; (f) is the bit log-likelihood ratio equalization value;

[0095] Fig.13 Schematic diagram of demodulation performance of PDSCH data block TBData, where (a) is the PDSCH transmission accuracy; (b) is the bit error rate of PDSCH data block TBData;

[0096] Fig.14 PDSCH simulation link block diagram for chirp interference;

[0097] Fig.15 The figure shows the time-frequency resource diagram of the transmitter and receiver of chirp interference under the CDL channel, where (a) is the discrete time-frequency resource diagram of the transmitter (txAnt1); (b) is the discrete time-frequency resource diagram of the transmitter (txAnt2); (c) is the discrete time-frequency resource diagram of the receiver (txAnt1); (d) is the discrete time-frequency resource diagram of the receiver (txAnt2);

[0098] Fig.16 The Bode diagram corresponding to the notch filter at the positions corresponding to the center subcarriers 496 and 556;

[0099] Fig.17 The time-frequency resource diagrams of the transmitter and receiver of chirp interference under CDL channel, (a) is the discrete time-frequency diagram of the transmitter (txAnt1); (b) is the discrete time-frequency diagram of the transmitter (txAnt2); (c) is the discrete time-frequency diagram of the receiver (txAnt1); (d) is the discrete time-frequency diagram of the receiver (txAnt2);

[0100] Fig.18 The timing and frequency synchronization performance of setting the timing offset 107 and the frequency offset 100 Hz when chirp interference exists in the CDL channel, where (a) is frequency synchronization; (b) is timing synchronization;

[0101] Fig.19 : The PDSCH channel equalization performance diagram under chirp interference in the CDL channel, where (a) is the constellation diagram corresponding to QPSK at the receiving end (txAnt1); (b) is the constellation diagram corresponding to QPSK after equalization at the receiving end (txAnt1); (c) is the constellation diagram corresponding to QPSK at the receiving end (txAnt2); (d) is the constellation diagram corresponding to QPSK after equalization at the receiving end (txAnt2); (e) is the bit log-likelihood ratio; (f) is the bit log-likelihood ratio equalization value;

[0102] Fig. 20 Schematic diagram of the demodulation performance of the PDSCH data block TBData under chirp interference in the CDL channel, where (a) is the PDSCH transmission accuracy; (b) is the bit error rate of the PDSCH data block TBData. DETAILED DESCRIPTION

[0103] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0104] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0105] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0106] like Figure 1 As shown, the present invention provides a method for mapping physical channel resources of PDSCH in a power wireless private network, which consists of two parts, namely, a PDSCH transmission part and a PDSCH reception part. The PDSCH transmission part consists of 5GNR PDSCH channel coding and 230MHz PDSCH resource mapping. The PDSCH reception part consists of interference filtering, 230MHz PDSCH resource demapping, timing synchronization, frequency synchronization, channel estimation and equalization, and 5GNR PDSCH channel decoding.

[0107] 5GNR PDSCH channel coding: The channel coding link of the power wireless private network PDSCH is composed of the standard 5GNR PDSCH channel coding link, which specifically includes transmission information data blocks, scrambling, coding block segmentation, LDPC (Low-Density Parity-Check Coding) coding, rate matching and modulation mapping, as well as PDSCH resource mapping. After the PDSCH data block at the transmitting end is processed by this module, the 5GNR PDSCH modulated data block is obtained, and the demodulation reference signal is jointly mapped into a standard 5GNR PDSCH resource block, which includes data and demodulation reference signal (DMRS for short).

[0108] 230MHz PDSCH resource mapping: Map the standard 5GNR PDSCH resource block to the power wireless private network resource grid (4096×20) to form a 230MHz PDSCH resource block. When mapping the standard 5GNR PDSCH resource block, the power wireless private network resource grid can only carry one terminal standard 5GNR PDSCH resource block, but multiple terminal standard 5GNR PDSCH resource blocks can be transmitted in one power wireless private network resource grid at the same time, and they occupy different subcarriers and OFDM symbols. When allocating power wireless private network resources, the network gives priority to selecting the resource blocks with the most continuous subcarriers to carry PDSCH transmission. The power wireless private network resource grid is modulated by OFDM to form the power wireless private network frame data.

[0109] Interference filtering: The power wireless private network resource grid consists of 4096 2.5KHz subcarriers and 20 OFDM symbols, but it can be used non-continuously in the frequency domain. There are some 25KHz subbands used by other systems, which are called interference subbands. When the 5G NRPDSCH resource block is mapped to the power wireless private network resource grid, the interference subband needs to be filtered out from the 230MHz PDSCH resource block. In the present invention, a notch filter is used to remove the interference subband, and the center frequency of the notch filter is the center frequency of the 25KHz interference subband.

[0110] 230MHz PDSCH resource demapping: Receive the airborne power wireless private network frame data, remove the interference sub-band through the interference filter, perform OFDM demodulation, and obtain the power wireless private network resource grid. According to the transmitter, determine the time-frequency resource position of the 230MHz PDSCH resource block, and take the 5GNR PDSCH resource block from the power wireless private network resource grid to obtain a complete 5GNR PDSCH resource block, which includes data and demodulation reference signals.

[0111] Timing synchronization: obtain the 230MHz PDSCH resource block from the 230MHz PDSCH resource demapping module, retain the demodulation reference signal in the 230MHz PDSCH resource block, set all its data parts to zero, and form a received reference signal data block. In addition, the demodulation reference signal in the local PDSCH is used and mapped to the power wireless private network resource grid using the method of mapping the demodulation reference signal at the transmitting end to form a local reference signal data block. Then the conjugate point multiplication of the received reference signal data block and the local reference signal data block is performed, and the sum is calculated in the frequency domain to obtain the demodulation reference signal frequency domain correlation array, and the array is transformed into a time domain impact array by inverse fast Fourier transform (abbreviated as IFFT), and the position of the maximum value is the timing synchronization position.

[0112] Frequency synchronization: In the received reference signal data block and the local reference signal data block, there are at least two OFDM symbols containing demodulation reference signals. First, the phase difference between the received and local reference signal data blocks is calculated respectively, and the magnitude of the frequency offset is estimated using the phase difference of adjacent demodulation reference signals to complete frequency synchronization.

[0113] Channel estimation and equalization: The 230MHz PDSCH resource block in the power wireless private network resource grid is first divided into multiple 230MHz PDSCH sub-resource blocks. Each 230MHz PDSCH sub-resource block uses the least squares (LS) method based on the local demodulation reference signal to obtain the channel matrix and noise variance with the minimum error calculation. Then, the minimum mean square error (MMSE) is used to calculate the equalizer weight matrix, and the received signal is input into the equalizer to complete the equalization. Finally, all the 230MHz PDSCH sub-resource block equalization results are spliced ​​into a complete 5GNR PDSCH modulation data block.

[0114] 5GNR PDSCH channel decoding: The channel decoding link of the power wireless private network PDSCH is composed of the standard 5GNR PDSCH channel decoding link, which includes demodulation, rate matching, LDPC decoding, coding block reorganization, descrambling and verification. The 5GNR PDSCH modulated data block is processed by this module to obtain the PDSCH data block.

[0115] In terms of the process, the present invention has a total of 4 processes, namely, process one: PDSCH channel encoding and decoding and resource mapping process; process two: timing synchronization process; process three: frequency synchronization process; process four: channel estimation and equalization process.

[0116] Process 1: PDSCH channel encoding and decoding and resource mapping process, such as Figure 2 shown.

[0117] Step 1: The PDSCH channel coding of the power wireless private network is fully compatible with the standard 5GNR PDSCH channel coding process. According to the standard 5GNR definition of PDSCH channel coding, the PDSCH data block is scrambled, coded block segmented, LDPC encoded, rate matched and modulated to form a 5GNR PDSCH modulated data block, which is then mapped together with the demodulation reference signal to form a complete 5GNR PDSCH resource block.

[0118] Step 2: In the standard 5GNR frame structure, each time slot consists of 14 OFDM symbols, and the maximum PDSCH time domain resource allocation is defined in time slots, occupying part or all of the time-frequency resources according to the transmission PDSCH resource requirements. In the power wireless private network, the power wireless private network radio frame length is 10ms, consisting of 20 OFDM symbols. The power wireless private network radio frame can carry the 5GNR PDSCH resource block of one terminal, and can also carry the 5GNR PDSCH resource blocks of multiple terminals at the same time. These resource blocks occupy different time-frequency resources in the power wireless private network resource grid.

[0119] Step 3: Standard 5GNR PDSCH resource blocks occupy time-frequency resources with physical resource blocks (PRBs) as the smallest unit. Each PRB contains 12 consecutive subcarriers, in which the demodulation reference signal is embedded. The time-frequency resource grid of the power wireless private network is a discretely distributed subcarrier resource, and there is a non-continuous characteristic between its subcarrier resource blocks. The 5GNR PDSCH resource block is remapped to adapt to the power wireless private network resource grid.

[0120] Step 4: Map the standard 5GNR PDSCH resource block to the power wireless private network resource grid, occupy 12N (N is a positive integer) subcarriers in the frequency domain, and there may be unavailable 25KHz subbands in the 12N subcarriers. Occupy the same number of OFDM symbols in the time domain, and finally map the standard 5GNR PDSCH resource block to a 230MHz PDSCH resource block. The power wireless private network resource grid is modulated by OFDM to obtain the power wireless private network frame data.

[0121] Step 5: At the receiving end, the received power wireless private network frame data is subjected to interference filtering, and OFDM demodulation is performed to obtain the power wireless private network resource grid. According to the standard 5GNR PDSCH resource block mapping rule of the transmitting end, the 230MHz PDSCH resource block is taken out from the power wireless private network resource grid, and remapped to obtain the 5GNR PDSCH resource block, which includes data and demodulation reference signals. The demodulation reference signal is used for timing synchronization, frequency synchronization, channel estimation and equalization to obtain the PDSCH modulated data block, and then the standard 5GNR PDSCH channel decoding process is performed to obtain the transmitted PDSCH data block.

[0122] Process 2: Timing synchronization process, such as Figure 3 shown.

[0123] Step 1: Remap the demodulation reference signal in the local standard 5GNR PDSCH resource block to the power wireless private network resource grid (4096×20). The power wireless private network resource grid only carries the local demodulation reference signal, and all other time-frequency resources are set to zero to form a local reference signal data block. The time domain signal waveform is received at the receiving end, and OFDM demodulation is performed on it to obtain the power wireless private network resource grid. In this resource grid, only the demodulation reference signal corresponding to the 5GNR PDSCH is retained, and the other parts are set to zero to form a received reference signal data block.

[0124] Step 2: Perform conjugate point multiplication on the local reference signal data block and the received reference signal data block, and add the conjugate point multiplication results of the corresponding subcarrier positions in the frequency domain to obtain the reference signal frequency domain correlation array. Perform fast Fourier transform on the array to obtain the time domain impact array. The position of the maximum value is the timing synchronization position, which is the timing synchronization point d of the power wireless private network frame data, such as Figure 3 As shown, the calculation process is:

[0125]

[0126]

[0127] in,"() * " represents complex conjugate operation; "max()" represents taking the maximum value from the array; "abs()" represents modulo calculation; N represents the number of reference signal OFDM symbols; rx_dmrs(n) represents the received reference signal data block; pdsch_dmrs_s(n) is the local reference signal data block; IFFT represents inverse fast Fourier transform; pdsch_dmrs_C(d) is the correlation value at d timing offsets, where d is the position deviation between the received and local reference signal data blocks.

[0128] Step 3: Compensate the received signal according to the timing synchronization position d. The calculation process is:

[0129] rx_TimeSync_waveform(n)=rx_waveform(n+d),n=0,...,N-1

[0130] Among them, rx_waveform represents the received power wireless private network frame data; rx_TimeSync_waveform represents the power wireless private network frame data after timing precision synchronization.

[0131] Process 3: Frequency synchronization process, the overall steps are as follows Figure 4 shown.

[0132] Step 1: At the receiving end, the timing-compensated power wireless network frame data rx_TimeSync_waveform is demodulated through OFDM to obtain the power wireless network resource grid. According to the corresponding position of the 230MHz PDSCH resource block in the power wireless network, the reference signal data on each OFDM is taken out to form the received reference signal data, which is recorded as rx_dmrs_data[m][n], where the subscript m represents the number of the reference signal on the carrier and n represents the number on the OFDM symbol.

[0133] Step 2: According to the rule of generating 5GNR PDSCH demodulation reference signal at the transmitter, the same 5GNR PDSCH demodulation reference signal is generated at the receiver to form local reference signal data, recorded as tx_dmrs_data[m][n], where the subscript m represents the number of the reference signal on the carrier and n represents the number on the OFDM symbol.

[0134] Step 3: Perform conjugate point multiplication on the received reference signal data rx_dmrs_data[m][n] and the local reference signal data tx_dmrs_data[m][n] to obtain the received and local reference signal phase difference matrix, recorded as dmrs_phaseDifference[m][n]. Calculation formula

[0135] dmrs_phaseDifference[m][n]=angle(rx_dmrs_data[m][n]·(tx_dmrs_data[m][n]) * )

[0136] Among them: “·” represents dot product; “() * " indicates conjugate calculation; "angle()" indicates taking the phase angle of all members.

[0137] Step 4: The reference signal phase difference matrix dmrs_phaseDifference[m][n] is averaged in the frequency domain to obtain a reference signal phase difference array.

[0138]

[0139] Where: “M” indicates the number of subcarriers occupied by the reference signal.

[0140] Step 5: Assuming the reference signal phase difference array dmrs_phaseAvgDifference[n], calculate the average value Δθ of the phase difference between adjacent reference signals. Calculation formula:

[0141]

[0142] Where: “l” represents the number of OFDMs carrying reference signals.

[0143] Step 6: Calculate the frequency deviation based on the phase difference Δθ caused by the two adjacent reference signals during the transmission process, and then perform frequency deviation compensation on the power wireless private network frame data rx_TimeSync_waveform to obtain the power wireless private network frame data rx_fine_waveform(n). Calculation formula:

[0144]

[0145] Wherein: Δf is the frequency deviation value; T is the time interval between two reference signals.

[0146] Process 4: Channel estimation and equalization process, such as Figure 5 shown.

[0147] Step 1: The receiving end receives the time domain signal waveform, recorded as rx_waveform(n), and after timing and frequency adjustment, recorded as rx_fine_waveform(n), performs OFDM demodulation on the signal to obtain the power wireless private network resource grid. According to the 230MHz PDSCH resource block mapping rule, the spectrum of the power wireless private network resource grid occupied by the 230MHz PDSCH is non-continuously distributed.

[0148] Step 2: Take out a 230 MHz PDSCH resource block from the power wireless private network resource grid, divide the 230 MHz PDSCH resource block into multiple 230 MHz PDSCH sub-resource blocks, and define the 230 MHz PDSCH resources occupying consecutive subcarriers as a sub-resource block.

[0149] Step 3: Assume that the reference channel and data in a 230MHz PDSCH sub-resource block are rx_fine_dmrs and rx_fine_data respectively. The demodulation reference signal of this sub-block in the local 5GNR PDSCH is recorded as tx_dmrs_data, which is used for least squares (LS) channel estimation. The calculation process is:

[0150] H LS =(X H X) -1 X H Y=X -1 Y

[0151] The corresponding LS channel estimation on each subcarrier can be expressed as:

[0152]

[0153] Among them, X[k] is the local reference signal tx_dmrs_data; Y[k] is the received reference signal rx_fine_dmrs; k is the subcarrier number; N is the number of demodulation reference signals in each OFDM symbol.

[0154] Step 4: Channel estimation result H of 230MHz PDSCH sub-resource block LS [k], k = 0, 1, ..., N-1, in the frequency domain, it is a discrete non-continuous state. In order to obtain complete channel estimation information in the entire continuous subcarrier range, a linear interpolation method is used. The calculation process is:

[0155]

[0156] Among them, H[k j ] is the interpolated channel estimate, k j Located in k a With k b Between; H LS [k a ] and H LS [k b ] is a known value for LS channel estimation.

[0157] Step 5: Using the channel estimation matrix H, adopt the MMSE equalizer weight matrix After completing channel equalization on the received signal rx_fine_data, the PDSCH sub-block data is obtained. The calculation process is:

[0158]

[0159] X[k]=W[k]Y[k],k=0,1,...,N-1

[0160] Among them, X[k] is the PDSCH sub-block data after equalization; Y[k] is the PDSCH sub-block data rx_fine_data before equalization; N is the PDSCH sub-block data size; express

[0161] Step 6: Using the same principle, perform channel estimation and equalization on all 230MHz PDSCH sub-resource blocks in the 230MHz PDSCH resource block, equalize the data in all PDSCH sub-resource blocks and splice them into a complete 5G NRPDSCH data block, and finally perform the 5G NR channel decoding process.

[0162] In order to clearly illustrate the specific meaning and usage of the present invention, this embodiment will use a MATLAB simulation embodiment to further illustrate the data transmission method of the present invention in a power wireless private network system.

[0163] Process 1: nr230Redcap's PDSCH receiving and transmitting links and mapping process

[0164] This embodiment uses MATLAB for simulation verification to simulate the transmission and reception process of one frame (10 milliseconds, 10ms) of PDSCH data in the power wireless private network. According to the content of the present invention, the parameters of the simulation setting in this embodiment are shown in Table 1. Table 2 provides resource blocks that can be used by the power wireless private network. The table has proposed unavailable 15KHz subbands and subcarrier resources that cannot form 12 consecutive integers.

[0165] Table 1

[0166]

[0167] Table 2

[0168]

[0169] Specific verification link block diagram, such as Figure 6 shown.

[0170] In this verification link, the standard 5GNR PDSCH resource block, denoted as tx5gNrGrid, occupies 14 consecutive OFDM symbols in the time domain and 12×50=600 consecutive subcarriers in the frequency domain. In tx5gNrGrid, DMRS occupies OFDM symbol positions 2 and 11, and occupies frequency domain resources with an interval of 1, such as 1, 3, ..., 597, 599. The PDSCH modulation mode is quadrature phase shift keying (QPSK), with a code rate of 0.478 and a layer mapping number of 2; the number of transmitting antennas is 2, and the number of receiving antennas is 2.

[0171] The MATLAB simulation platform is used to verify the transmission link of tx5gNrGrid in the power wireless private network resource grid. In this embodiment, tx5gNrGrid is remapped to the power wireless private network resource grid txNr230Grid to form a 230MHz PDSCH resource block. The power wireless private network resource grid txNr230Grid is modulated by OFDM to form power wireless private network frame data, recorded as txWaveform. txWaveform is simulated through the NR channel (CDL) to output power wireless private network frame data, recorded as rxWaveform. After OFDM demodulation, rxWaveform forms a power wireless private network resource grid, recorded as rxNr230Grid. Then, through the process two of this embodiment, timing synchronization, frequency synchronization, channel estimation and equalization are completed and spliced ​​into a complete 5G NRPDSCH modulated data block, recorded as rx5gNrBurstGrid, and the PDSCH channel decoding and post-processing are completed to obtain the PDSCH data block, recorded as TBData.

[0172] according to Figure 6 The simulation link structure shown in the figure is as follows:

[0173] Step 1: The PDSCH data block at the transmitting end passes through the standard 5GNR PDSCH channel coding link, and after processing, the 5GNR PDSCH modulated data block is obtained, the joint demodulation reference signal is mapped into a standard 5GNR PDSCH resource block (600x14x2), recorded as tx5gNrGrid. The generated tx5gNrGrid fully complies with the 3GPP standard, such as Figure 7 As shown in (a) in .

[0174] Note: This step fully reflects that the channel coding and decoding process of the PDSCH link is fully compatible with the 5G NRPDSCH process of the 3GPP standard.

[0175] Step 2: Map the 5GNR PDSCH resource block tx5gNrGrid to the power wireless private network resource grid (4096×20), recorded as txNr230Grid, where the wireless resource block occupied by tx5gNrGrid is called the 230MHz PDSCH resource block, recorded as tx230PdschGrid, such as Figure 7 In (b), the mapping process is as follows Figure 8 As shown, during the mapping process, the tx5gNrGrid resources need to be mapped to the available power wireless private network resource grid txNr230Grid according to the frequency domain and time domain correspondence.

[0176] Note: In this embodiment, the available subcarriers are shown in Table 2. There are 600 2.5KHz subcarriers in total.

[0177] Step 3: Perform OFDM modulation on the power wireless private network resource grid txNr230Grid, perform 4096-point inverse fast Fourier transform (IFFT) on each OFDM symbol in txNr230Grid, obtain 4096-point OFDM symbol data, and add a 1024-point cyclic prefix to the head to form a complete OFDM symbol time domain data, a total of 20 OFDM symbols, and generate a wireless frame (10ms) length of the power wireless private network frame data (102400x2), recorded as txWaveform, such as Fig. 9 As shown in (a) and (b).

[0178] Note 1: The subcarrier interval of the power wireless private network is 2.5KHz, and a 4096-point IFFT is used, so the sampling frequency of the power wireless private network frame data is 4096x2.5KHz=10240KHz.

[0179] Note 2: Although the tx5gNrGrid resource block and the tx230PdschGrid resource block carry the same content, the subcarriers in the tx5gNrGrid resource block are allocated continuously, while the subcarriers in the tx230PdschGrid resource block may be non-continuous.

[0180] Step 4: The power wireless private network frame data txWaveform passes through the simulated CDL channel. Output power wireless private network frame data, recorded as rxWaveform, such as Fig. 9 As shown in (g) and (h). In this embodiment, the channel model provided by MATLAB is used. The channel model sampling clock selects the power wireless private network sampling frequency of 10240KHz defined in the present invention. In the simulation, different signal-to-noise ratios can be selected to evaluate the PDSCH channel decoding performance. This step fully proves the feasibility of 2.5KHz subcarrier spacing in actual 5G NR channels.

[0181] Step 6: At the receiving end, the power wireless private network frame data rxWaveform is OFDM demodulated to form a power wireless private network resource grid (4096x20x2), recorded as rxNr230Grid. The local reference signal data block (4096x20x2), recorded as refDMRSGrid, is used to complete the timing synchronization and calculate the timing offset Timingoffset. The timing offset compensation is completed for the received signal rxWaveform to form the power wireless private network frame data, recorded as rxTimeSyncWaveform.

[0182] Note: The definition of the rxNr230Grid resource block on the receiving end and the txNr230Grid resource block on the transmitting end are exactly the same.

[0183] Step 7: Perform OFDM demodulation on the timing compensated rxTimeSyncWaveform to form a power wireless private network resource grid, recorded as rxTimeSyncNr230Grid. Use the local reference signal data block refDMRSGrid to complete frequency synchronization, calculate the frequency offset Freqoffset, and complete the frequency offset compensation for the received signal rxTimeSyncWaveform to form the power wireless private network frame data, recorded as rxFreqSyncWaveform.

[0184] Step 8: Perform OFDM demodulation on the frequency compensated rxFreqSyncWaveform, and record the power wireless network resource grid as rxNr230Grid. Fig.10 In the mapping process shown, rxNr230Grid is mapped into rx5gNrBurstGrid resource block, and refDMRSGrid is used to complete channel estimation and equalization in PDSCH sub-block mode, and then spliced ​​into a complete 5GNR PDSCH modulated data block. After completing the channel decoding of PDSCH, the PDSCH data block is obtained, which is recorded as TBData.

[0185] Process 2: Timing synchronization, frequency synchronization, channel estimation and equalization process.

[0186] After mapping the 5GNR PDSCH resource block tx5gNrGrid to the power wireless private network resource grid, the power wireless private network resource grid txNr230Grid, a series of synchronization and compensation steps are required, including timing synchronization, frequency synchronization, channel estimation and equalization. These steps all rely on the local reference signal data block refDMRSGrid and the received reference signal data block rxDMRSGrid. In this embodiment, DMRS occupies two OFDM symbol positions: 2 and 11, and the number of subcarriers occupied is 300.

[0187] The specific timing synchronization, frequency synchronization, channel estimation and equalization process of tx5gNrGrid during power wireless private network resource grid transmission is as follows:

[0188] Step 1: The demodulation reference signal DMRS in the local standard 5GNR PDSCH resource block tx5gNrGrid is remapped to the power wireless private network resource grid. The power wireless private network resource grid only carries the local demodulation reference signal DMRS, and all other time-frequency resources are set to zero to form a local reference signal data block (4096x20x2), recorded as refDMRSGrid.

[0189] Step 2: Receive the time domain signal waveform rxWaveform at the receiving end, perform OFDM demodulation on it, and obtain the power wireless private network resource grid. In this resource grid, only the demodulation reference signal corresponding to 5GNR PDSCH is retained, and the other parts are set to zero to form a received reference signal data block (4096x20x2), recorded as rxDMRSGrid.

[0190] Step 3: Perform conjugate point multiplication on refDMRSGrid and rxDMRSGrid, accumulate the conjugate point multiplication results of the corresponding subcarrier positions in the frequency domain, and take the average in the third dimension to obtain the reference signal frequency domain correlation array. Perform a fast Fourier transform on the array to obtain the time domain impact array, and find the position of the maximum value, which is the timing offset Timingoffset of the power wireless private network frame data:

[0191]

[0192] in,"() * " indicates complex conjugate operation; "max()" indicates taking the maximum value from the array; "abs()" indicates modulo calculation; N indicates the number of reference signal OFDM symbols 2; rxDMRSGrid indicates the received reference signal data block; refDMRSGrid indicates the local reference signal data block; IFFT indicates inverse fast Fourier transform; Timingoffset indicates the timing offset value.

[0193] Step 4: At the receiving end, the timing-compensated power wireless network frame data rxTimeSyncWaveform is demodulated through OFDM to obtain the power wireless network resource grid rxTimeSyncNr230Grid. According to the corresponding position of the 230MHz PDSCH resource block tx230PdschGrid in the power wireless network, the reference signal data on each OFDM is taken out to form the received reference signal data (300x2x2), rxTimeSyncDMRSGrid.

[0194] Step 5: According to the rule of generating 5GNR PDSCH demodulation reference signal at the transmitting end, the same 5GNR PDSCH demodulation reference signal is generated at the receiving end to form local reference signal data (300×2×2), which is recorded as refTimeSyncDMRSGrid.

[0195] Step 6: After conjugate point multiplication of the received reference signal data rxTimeSyncDMRSGrid and the local reference signal data refTimeSyncDMRSGrid, the third dimension is averaged to obtain the received and local reference signal phase difference matrix (300×2), recorded as DMRSPhaseDifference. Calculation formula:

[0196] DMRSPhaseDifference=angle(rxTimeSyncDMRSGrid·refTimeSyncDMRSGrid * )

[0197] Among them: “·” represents dot product; “() * " indicates conjugate calculation; "angle()" indicates taking the phase angle of all members.

[0198] Step 7: Perform average calculation on the reference signal phase difference matrix DMRSPhaseDifference in the frequency domain to obtain a reference signal phase difference array.

[0199]

[0200] Wherein: “M” indicates that the number of subcarriers occupied by the reference signal is 300.

[0201] Step 8: Assuming the reference signal phase difference array DMRSPhaseDifference[n], calculate the average value Δθ of the phase differences between adjacent reference signals. Calculation formula:

[0202]

[0203] Wherein: “1” represents the number of OFDM packets carrying reference signals, which is 2.

[0204] Step 9: Calculate the frequency deviation according to the phase difference Δθ caused by the two adjacent reference signals during the transmission process, and then perform frequency deviation compensation on the power wireless private network frame data rxTimeSyncWaveform to obtain the power wireless private network frame data rxFreqSyncWaveform. Calculation formula:

[0205]

[0206] Wherein: Freqoffset is the frequency offset value; T is the time interval between two reference signals.

[0207] When the subcarrier spacing SCS is 2.5KHz, the range of frequency offset estimation in this example is:

[0208]

[0209]

[0210]

[0211] Step 10: After the timing and frequency adjustment, the power wireless private network frame data rxFreqSyncWaveform is OFDM demodulated to obtain the power wireless private network resource grid. According to the 230MHz PDSCH resource block mapping rule, the spectrum occupied by the 230MHz PDSCH in the power wireless private network resource grid is non-continuously distributed.

[0212] Step 11: Divide the 230 MHz PDSCH resource block tx230PdschGrid into multiple 230 MHz PDSCH sub-resource blocks, and define the 230 MHz PDSCH resources occupying consecutive subcarriers as a sub-resource block, denoted as SubrxNr230Grid.

[0213] Step 12: The reference channel and data in a 230MHz PDSCH sub-resource block SubrxNr230Grid are rxFineDMRS and rxFineDATA respectively. The demodulation reference signal of the local 5GNR PDSCH of this sub-block is denoted as refDMRAData, which is used for least squares (LS) channel estimation. The calculation process is:

[0214]

[0215] Step 13: Channel estimation result H of 230MHz PDSCH sub-resource block SubrxNr230Grids LS , in the frequency domain, it is a discrete and discontinuous state. In order to obtain complete channel estimation information in the entire continuous subcarrier range, a linear interpolation method is used. The calculation process is:

[0216]

[0217] Among them, H[k j ] is the interpolated channel estimate, k j Located in k a With k b Between; H LS [k a ] and H LS [k b ] is a known value for LS channel estimation.

[0218] Step 14: Using the channel estimation matrix H, adopt the MMSE equalizer weight matrix After completing channel equalization on the received signal rxFineDATA, the PDSCH sub-block data is obtained. The calculation process is:

[0219]

[0220] X[k]=W[k]Y[k],k=0,1,...,N-1

[0221] Among them, X[k] is the PDSCH sub-block data after equalization, recorded as rxMMSEFineDATA; Y[k] is the PDSCH sub-block data rxFineDATA before equalization; N is the PDSCH sub-block data size; express

[0222] Step 15: Using the same principle, all 230MHz PDSCH sub-resource blocks SubrxNr230Grid in the 230MHz PDSCH resource block are channel estimated and equalized, and the data in all PDSCH sub-resource blocks are equalized and spliced ​​into a complete 5GNR PDSCH modulated data block (600x14x2). Finally, the 5GNR channel decoding process is performed, and the PDSCH data block is obtained after the channel decoding of the PDSCH, which is recorded as TBData.

[0223] Scenario 1: Impact of timing, frequency synchronization, channel estimation and equalization on PDSCH channel decoding in the absence of interference subbands in CDL channel scenario

[0224] In scenario 1, assuming that the spectrum resources of the power wireless private network resource grid are not occupied by other systems, the clustered delay line (CDL) channel model is used for simulation. The CDL channel model can simulate the multipath propagation characteristics of signals in a real environment, increasing the realism and complexity of the simulation. In this embodiment, Table 1 lists the parameter configuration of scenario 1 in detail, providing a complete definition of the system simulation environment.

[0225] In this scenario, the subcarriers of the 5GNR PDSCH resource block are spectrally distributed in the power wireless private network resource grid in a discrete manner, strictly following the spectrum resource configuration requirements of the resource grid. At these subcarrier positions, no other signal interference occurs, thus ensuring the high purity and reliability of the 5GNR PDSCH resource block transmission process. The channel decoding performance of PDSCH is evaluated under different signal-to-noise ratio (SNR) conditions, and 500 simulations are completed using the Monte Carlo method to verify the stability of the signal performance under the CDL channel.

[0226] Fig.11 The frequency synchronization and timing synchronization performance of the present invention under CDL channel conditions is demonstrated, and the effectiveness and robustness of the proposed method in complex channel environments are further verified.

[0227] Fig.11(a) depicts the changing trend of frequency synchronization performance. It can be observed that with the increase of signal-to-noise ratio (SNR), the frequency offset estimation value gradually approaches the actual frequency offset value. When the signal-to-noise ratio is greater than -20dB, the frequency offset estimation value is completely consistent with the actual frequency offset value, and the system can fully compensate for the impact of frequency offset on signal demodulation. The proposed method can still effectively improve the impact of frequency offset on the system within the entire SNR range, and the scheme can significantly reduce the impact of frequency offset on the demodulation performance of the system.

[0228] Fig.11 (b) shows the evaluation results of timing synchronization performance. As can be seen from the figure, when the SNR is lower than -40dB, although there is a certain error in the estimated value of the timing offset, as the SNR increases, the timing estimation performance improves significantly and rapidly. When the SNR is higher than -40dB, the timing estimate is completely consistent with the actual timing offset value, proving that this method can effectively compensate for the impact of the timing offset on the system and ensure the stability of the demodulation performance.

[0229] In summary, the performance difference between the frequency synchronization and timing synchronization modules under CDL channel conditions shows the impact of channel characteristics on synchronization accuracy. However, thanks to the proposed method's full modeling and compensation strategy for complex channel characteristics, the system can still maintain high efficiency of frequency and timing synchronization performance even in a more challenging multipath channel environment, thus providing a solid foundation for reliable demodulation of PDSCH signals.

[0230] The influence of the PDSCH mapping mode and the channel estimation and equalization module proposed in the present invention on PDSCH channel decoding under different signal-to-noise ratio (SNR) conditions is explored, and relevant experimental analysis is carried out. Fig.12 The changes in the performance of the PDSCH signal before and after channel equalization are presented, including the results of the QPSK constellation diagram and the bit log-likelihood ratio (LLR).

[0231] Fig.12 (a) and (c) show the QPSK constellation diagrams of the PDSCH signal before channel equalization for two receiving antennas in the CDL channel environment. It can be observed from the figure that the constellation point distribution of the received signal has a small phase rotation compared with the ideal case. Fig.12 (e) shows the distribution of the bit log-likelihood ratio (LLR) under CDL channel conditions, which exhibits a small dispersion and deviates from the ideal demodulation value.

[0232] In order to further improve the signal demodulation performance, a channel equalization module is introduced to perform amplitude and phase compensation on the received signal. Fig.12(b) and (d) show the QPSK constellation diagrams of the two receiving antennas after equalization. It can be clearly seen from the figure that the equalization process effectively corrects the imbalance of signal amplitude and phase, making the constellation points more concentrated in the ideal position, significantly improving the demodulation quality of the signal. At the same time, Fig.12 (f) shows the result of the bit log-likelihood ratio (LLR) after equalization. Compared with before equalization, the LLR distribution is clearer and closer to the ideal demodulation value, which shows that the channel equalization module significantly improves the soft decision performance of the signal, thereby improving the bit error rate performance of PDSCH.

[0233] In summary, the 5GNR PDSCH resource block mapping method proposed in the present invention combines the channel estimation and equalization modules to demonstrate superior demodulation performance under CDL channel conditions. Channel equalization not only effectively compensates for the phase and amplitude deviation of the signal, but also enhances the accuracy of soft decision, providing technical guarantee for reliable communication under low signal-to-noise ratio conditions.

[0234] Fig.13 It comprehensively demonstrates the performance of PDSCH data block transmission under different signal-to-noise ratio (SNR) conditions, including the changing trends of successful transmission rate (Throughput) and bit error rate (BER), and deeply reflects the transmission characteristics of the system in a complex channel environment.

[0235] Fig.13 (a) depicts the relationship between the successful transmission rate of PDSCH data blocks and the change of SNR. As can be seen from the figure, as the signal-to-noise ratio increases, the successful transmission rate of PDSCH gradually increases. When the SNR is lower than -30dB, the successful transmission rate decreases significantly, indicating that under low signal-to-noise ratio conditions, the signal is more seriously affected by noise interference, resulting in a higher probability of demodulation failure. However, when the SNR exceeds -30dB, the successful transmission rate increases rapidly to nearly 100%, indicating that the demodulation scheme can effectively cope with noise interference under low signal-to-noise ratio conditions. This result shows that the scheme proposed in this study can achieve reliable data block transmission in a low signal-to-noise ratio environment, ensuring the stability and efficiency of communication.

[0236] Fig.13(b) further analyzes the trend of PDSCH bit error rate (BER) changing with SNR. Under low SNR conditions, the SNR is lower than -30dB and the bit error rate is high, indicating that under this condition, the impact of noise on the received signal is more serious, and the channel equalization and demodulation schemes cannot completely eliminate the error. However, as the SNR increases, the bit error rate decreases rapidly. When the SNR reaches -30dB, the bit error rate drops to zero and remains in a zero error state thereafter. This shows that in a low SNR environment, the channel equalization module effectively eliminates the errors in the signal caused by multipath fading and noise interference, ensuring the integrity and transmission reliability of the PDSCH data block.

[0237] In summary, Fig.13 The effectiveness of the 5GNR PDSCH resource block transmission scheme proposed in this study in complex channel environments was verified. The demodulation scheme showed good robustness and reliability in terms of both successful transmission rate and bit error rate performance, providing strong technical support and performance guarantee for efficient data transmission in power wireless private networks.

[0238] Scenario 2: Impact of timing, frequency synchronization, channel estimation and equalization on PDSCH channel decoding in the presence of interfering subbands in CDL channel scenario

[0239] Scenario 2 uses the same system simulation experimental environment as Scenario 1. In Scenario 2, other systems are introduced to interfere with the PDSCH signal. In this embodiment, chirp signals are used to simulate other systems. The simulated chirp bandwidth is 25KHz, and the sampling rate of the generated chirp time domain signal is the same as the sampling rate of the power wireless private network, so that the time domain signals can be directly added and merged during the simulation process. Link Fig.14 shown.

[0240] In this scenario, in order to evaluate the impact of the Chirp signal on the decoding performance of the PDSCH channel, the Chirp signal is configured to occupy the subcarrier position occupied by the PDSCH in the power wireless private network resource grid. Specifically, the Chirp signal occupies the following subcarrier positions: 481, 482, 483, 484, 485, 486, 487, 488, 489, 490, 571, 572, 573, 574, 575, 576, 577, 578, 579, 580. The total bandwidth corresponding to these subcarrier positions is 50kHz. Since the spectrum distribution of the Chirp signal overlaps with that of the PDSCH signal, it directly interferes with the PDSCH data block and the DMRS (Demodulation Reference Signal) signal, thereby affecting the demodulation performance of the PDSCH signal and the transmission quality of the system.

[0241] Fig.15 (c) and Fig.15 (d) shows the spectrum and time domain performance of the PDSCH signal when it is interfered by Chirp. It can be observed that due to its significant power and wide spectrum characteristics, the Chirp signal not only covers the target frequency band, but also causes the PDSCH signal to be severely obliterated, especially in high-power conditions, the effective information of the PDSCH signal is almost completely submerged. This shows that when the Chirp signal is not properly processed, its interference effect on the PDSCH signal is significant and cannot be ignored.

[0242] In order to alleviate the interference effect of Chirp signal, this study proposes a signal interference suppression method based on notch filter. In the PDSCH demodulation process, by introducing a notch filter at the receiving end, the frequency band occupied by the Chirp signal is accurately filtered, thereby significantly reducing its interference to the PDSCH subcarrier. This method not only effectively weakens the interference intensity of the Chirp signal, but also ensures that the PDSCH signal can maintain a high degree of integrity and reliability during the demodulation process, and evaluates the robustness and anti-interference performance of the system under interference conditions.

[0243] The design process of the notch filter in this embodiment is as follows:

[0244] Due to the existence of 25kHz bandwidth interference sub-band signals such as Chirp and FSK signals, which occupy the spectrum resources of the 230MHz frequency band, the spectrum expansion of the interference signal seriously affects the demodulation of PDSCH. According to the content of the invention, this embodiment now adopts a notch filter, and by setting corresponding filter parameters, the interference signal in the specified frequency band can be filtered out to ensure the normal demodulation of PDSCH.

[0245] Step 1. Input the received signal RxWaveform into the notch filter to filter out the frequency band corresponding to the interference signal. In the notch filter, except for the notch frequency band where the amplitude gain is 0, the amplitude gain of other frequency bands is 1, which means that except for the frequency signal that will attenuate the interference signal, other frequency signals will remain unchanged. Fig.16 The Bode diagram corresponding to the Chirp and FSK interference signals with a bandwidth of 10MHz, the transfer function of the notch filter is:

[0246]

[0247] Step 2: The signal processed by the notch filter is passed to the timing offset estimation module and the frequency offset estimation module for timing synchronization and frequency synchronization.

[0248] 230MHz PDSCH resource block and 5GNR PDSCH modulation data block after notch filter processing, such as Fig.17 As shown in (c)-(d). Fig.17(c)-(d) show in detail the effective subcarrier positions of the PDSCH block occupied by the Chirp signal, and how the Chirp signal affects the corresponding positions of consecutive subcarriers of the PDSCH block after channel equalization, further revealing the impact of the Chirp signal on the occupancy of the PDSCH resource grid.

[0249] Fig.18 The frequency synchronization and timing synchronization performance of the system is demonstrated when it is interfered by Chirp signals in a CDL channel environment, and the effectiveness and robustness of the proposed method in a complex communication environment are verified.

[0250] Fig.18 (a) depicts the changing trend of frequency synchronization performance. It can be observed that with the improvement of signal-to-noise ratio (SNR), the frequency offset estimation value gradually approaches the actual frequency offset value. However, the signal is interfered by the Chirp signal, so the frequency synchronization performance is reduced compared with scenario 1 in the entire SNR range. Nevertheless, the proposed method can still effectively improve the impact of frequency offset on the system in the entire SNR range, indicating that the scheme can significantly reduce the impact of frequency offset on the demodulation performance of the system.

[0251] Fig.18 (b) shows the evaluation results of the timing synchronization performance. As can be seen from the figure, the signal is interfered by the chirp signal, so the timing synchronization performance is reduced compared with scenario 1 in the low SNR range. The proposed method can still accurately complete the timing synchronization under a relatively high signal-to-noise ratio and effectively compensate for the impact of the timing offset on the system.

[0252] Fig.19 The influence of the channel on the PDSCH signal demodulation performance under the interference of Chirp signals in the CDL channel environment and the effect of compensating the signal through the channel equalization module are demonstrated.

[0253] Fig.19 (a) and Fig.19 (c) shows the QPSK constellation diagram of the PDSCH signal received by the two receiving antennas. Due to the high power and wide spectrum interference of the Chirp signal, the gain and phase distortion of the signal are further aggravated under the CDL channel conditions, resulting in obvious offset and rotation of the constellation points. The high degree of scatter in the distribution of the constellation points indicates that both the amplitude and phase of the signal are significantly affected. This distortion directly affects the demodulation performance, resulting in a higher bit error rate. In addition, Fig.19 (e) shows the bit log-likelihood ratio (LLR) distribution when no equalization is performed. It can be observed that it exhibits a large dispersion and is far away from the ideal value, indicating that the soft decision performance of the received signal is significantly degraded and the demodulation accuracy is severely limited.

[0254] To deal with the above interference, this solution introduces a channel equalization module to achieve signal compensation and recovery by correcting the amplitude and phase of the signal. After equalization, the QPSK constellation diagram of the two receiving antennas is as follows: Fig.19 (b) and Fig.19 As shown in (d) in the figure. Although the equalization effect is slightly affected compared with scenario 1, the distribution of constellation points after equalization is obviously more concentrated and close to the ideal position. This shows that the channel equalization module can effectively correct the phase rotation and amplitude offset caused by the CDL channel and Chirp signal interference. In addition, Fig.19 As can be seen in (f), the LLR distribution after equalization is significantly improved, closer to the ideal soft decision value, and the distribution concentration is significantly enhanced.

[0255] Fig. 20 The transmission performance of PDSCH data blocks in the CDL channel environment with superimposed Chirp signal interference is fully demonstrated, including the trend of successful transmission rate (Throughput) and bit error rate (BER, Bit Error Rate) changing with signal-to-noise ratio (SNR). These results reveal the changing law of the system's transmission characteristics in an interference environment and verify the applicability and robustness of the proposed scheme.

[0256] Fig. 20 (a) shows the relationship between the successful transmission rate of PDSCH data blocks and SNR. As the signal-to-noise ratio increases, the successful transmission rate shows an obvious gradual upward trend. When the SNR is lower than -30dB, the successful transmission rate decreases significantly, indicating that the signal is affected by both Chirp interference and noise, and the probability of signal demodulation failure increases significantly. However, when the SNR exceeds -30dB, the successful transmission rate increases rapidly, indicating that the demodulation scheme can effectively cope with the influence of noise interference under medium and high signal-to-noise ratio conditions. In particular, when the SNR is further increased to a higher level, the transmission success rate is close to 100%, which fully verifies the reliability of the proposed method in a high signal-to-noise ratio environment. It is worth noting that compared with scenario 1 where the Chirp signal interference is not added, the successful transmission rate of PDSCH in this scenario is significantly affected under low signal-to-noise ratio conditions due to the spectrum expansion and high power characteristics of the Chirp signal. However, due to the addition of the notch filter, the successful transmission rate still shows a strong recovery ability in the medium and high signal-to-noise ratio range, indicating that the transmission performance of the system in a complex interference environment is still highly robust.

[0257] Fig. 20(b) further analyzes the trend of the bit error rate (BER) of PDSCH with SNR. When the SNR is lower than -30dB, the bit error rate increases significantly, indicating that the noise and Chirp signal interference work together to cause serious damage to the amplitude and phase of the received signal, making it difficult for the channel equalization and demodulation scheme to completely eliminate the error. However, as the signal-to-noise ratio increases, the bit error rate drops rapidly. When the SNR reaches -30dB, the bit error rate drops to zero and remains in a zero error state thereafter. Compared with scenario 1, the interference of the Chirp signal causes the bit error rate to increase significantly at low signal-to-noise ratios, but when the SNR is high, the proposed scheme can still show strong error suppression capabilities. In particular, after the SNR exceeds -30dB, the rapid convergence of the bit error rate indicates that the demodulation performance of the system has been effectively restored, and at the same time verifies the channel equalization module's ability to compensate for Chirp interference and its positive improvement on the PDSCH demodulation performance.

[0258] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A method for mapping PDSCH physical channel resources in a power wireless private network, characterized in that: The process includes: Process 1: PDSCH channel encoding and decoding and resource mapping process: At the transmitting end, the PDSCH channel is encoded into a 5GNR PDSCH resource block, and then the 5GNR PDSCH resource block is discretely mapped to the 230MHz wireless resource to form a discrete power wireless private network 230MHz PDSCH resource block; at the receiving end, the discrete power wireless private network 230MHz PDSCH resource block is restored to a standard 5GNR PDSCH resource, and the 5GNR PDSCH link is used for demodulation to obtain the transmitted PDSCH data block; Process 2: Timing synchronization process: retain the demodulation reference signal in the 230MHz PDSCH resource block, set all its data parts to zero, and form a receiving reference signal data block; use the demodulation reference signal in the local PDSCH, and use the method of mapping the demodulation reference signal at the transmitting end to map it to the power wireless private network resource grid to form a local reference signal data block; Then, the received reference signal data block and the local reference signal data block are conjugate-point multiplied, and summed up in the frequency domain to obtain the demodulation reference signal frequency domain correlation array, and the array is subjected to inverse fast Fourier transform IFFT to the time domain impulse array, and the position of the maximum value is the timing synchronization position; Process 3: Frequency synchronization process: First, the phase difference between the received and local reference signal data blocks is calculated respectively, and the magnitude of the frequency offset is estimated by using the phase difference of adjacent demodulation reference signals to complete frequency synchronization; Process 4: Channel estimation and equalization process: The 230MHz PDSCH resource block in the power wireless private network resource grid is first divided into multiple 230MHz PDSCH sub-resource blocks; each 230MHz PDSCH sub-resource block uses the least squares method to minimize the error calculation channel matrix and noise variance based on the local demodulation reference signal; then the minimum mean square error MMSE is used to calculate the equalizer weight matrix, and the received signal is input into the equalizer to complete the equalization. Finally, all the 230MHz PDSCH sub-resource block equalization results are spliced ​​into a complete 5GNR PDSCH modulation data block.

2. The method for mapping PDSCH physical channel resources in a power wireless private network according to claim 1, characterized in that: The PDSCH channel coding, decoding and resource mapping process includes: Step A1: Scramble, code block segment, LDPC encode, rate match and modulate the PDSCH data block to form a 5GNR PDSCH modulated data block, which is then mapped together with the demodulation reference signal to form a standard 5GNR PDSCH resource block; Step A2: Map the standard 5GNR PDSCH resource block to the power wireless private network resource grid to form a 230MHz PDSCH resource block, where the power wireless private network resource grid is 4096×20, indicating 4096 subcarriers and 20 orthogonal frequency division multiplexing (OFDM) symbols; the power wireless private network resource grid can carry 5GNR PDSCH resource blocks of multiple terminals at the same time, and these resource blocks occupy different subcarriers and OFDM symbols in the power wireless private network resource grid; Step A3: The standard 5GNR PDSCH resource block occupies the time-frequency resources with the physical resource block PRB as the smallest unit. Each PRB contains 12 consecutive subcarriers, in which the demodulation reference signal is embedded. The time-frequency resource grid of the power wireless private network is a discretely distributed subcarrier resource, and there is a non-continuous characteristic between its subcarrier resource blocks. The 5GNR PDSCH resource block is remapped to adapt to the power wireless private network resource grid; Step A4: Map the standard 5GNR PDSCH resource block to the power wireless private network resource grid, occupy 12N subcarriers continuously in the frequency domain; occupy the same number of OFDM symbols continuously in the time domain, and finally map the standard 5GNR PDSCH resource block to a 230MHz PDSCH resource block; the power wireless private network resource grid is modulated by OFDM to obtain the power wireless private network frame data; Step A5: At the receiving end, the received power wireless private network frame data is subjected to interference filtering and OFDM demodulation is performed to obtain the power wireless private network resource grid. According to the standard 5GNR PDSCH resource block mapping rule of the transmitting end, the 230MHz PDSCH resource block is taken out from the power wireless private network resource grid and remapped to obtain the 5GNR PDSCH resource block, which includes data and demodulation reference signals. The demodulation reference signal is used to perform timing synchronization, frequency synchronization, channel estimation and equalization to obtain the PDSCH modulated data block, and then the standard 5GNR PDSCH channel decoding process is performed to obtain the transmitted PDSCH data block.

3. The method for mapping PDSCH physical channel resources in a power wireless private network according to claim 2, characterized in that: The received power wireless private network frame data in step A5 is subjected to interference filtering, which uses a notch filter to filter out the interference subband in the 230MHz PDSCH resource block. The specific processing is as follows: The received signal is input into the notch filter to filter out the frequency band corresponding to the interference signal. In the notch filter, the amplitude gain of the notch frequency band is 0, and the amplitude gain of other frequency bands is 1. The transfer function of the notch filter is:

4. The method for mapping PDSCH physical channel resources in a power wireless private network according to claim 1, characterized in that: The timing synchronization process specifically includes the following steps: Step B1: remap the demodulation reference signal in the local standard 5GNR PDSCH resource block to the power wireless private network resource grid, which only carries the local demodulation reference signal, and all other time-frequency resources are set to zero to form a local reference signal data block; receive the time domain signal waveform at the receiving end, perform OFDM demodulation on it, and obtain the power wireless private network resource grid, in which only the demodulation reference signal corresponding to the 5GNR PDSCH is retained, and other parts are set to zero to form a received reference signal data block; Step B2: Perform conjugate point multiplication calculation on the local reference signal data block and the received reference signal data block, and accumulate the conjugate point multiplication results of the corresponding subcarrier positions in the frequency domain to obtain the reference signal frequency domain correlation array; perform fast Fourier transform on the array to obtain the time domain impact array, and find the position of the maximum value as the timing synchronization position, that is, the timing synchronization point d of the power wireless private network frame data. The calculation process is: in,() * represents complex conjugate operation; max() represents the maximum value in the array; abs() represents modulo calculation; N represents the number of reference signal OFDM symbols; rx_dmrs(n) represents the received reference signal data block; pdsch_dmrs_s(n) represents the local reference signal data block; IFFT represents the inverse fast Fourier transform; pdsch_dmrs_C(d) represents the correlation value at d timing offsets, where d is the position deviation between the received and local reference signal data blocks; Step B3: Compensate the received signal according to the timing synchronization position d. The calculation process is: rx_TimeSync_waveform(n)=rx_waveform(n+d),n=0,...,N-1 Among them, rx_waveform represents the received power wireless private network frame data; rx_TimeSync_waveform represents the power wireless private network frame data after timing precision synchronization.

5. The method for mapping PDSCH physical channel resources in a power wireless private network according to claim 1, characterized in that: The frequency synchronization process includes the following steps: Step C1: At the receiving end, the power wireless private network frame data rx_TimeSync_waveform after timing compensation is demodulated through OFDM to obtain the power wireless private network resource grid; according to the corresponding position of the 230MHz PDSCH resource block in the power wireless private network, the reference signal data on each OFDM is taken out to form the received reference signal data, which is recorded as rx_dmrs_data[m][n], where the subscript m represents the number of the reference signal on the carrier, and n represents the number on the OFDM symbol; Step C2: According to the rule for generating 5GNR PDSCH demodulation reference signal at the transmitting end, the same 5GNR PDSCH demodulation reference signal is generated at the receiving end to form local reference signal data, recorded as tx_dmrs_data[m][n], where the subscript m represents the number of the reference signal on the carrier, and n represents the number on the OFDM symbol; Step C3: Conjugate point multiplication is performed on the received reference signal data rx_dmrs_data[m][n] and the local reference signal data tx_dmrs_data[m][n] to obtain the received and local reference signal phase difference matrix, recorded as dmrs_phaseDifference[m][n], and the calculation formula is: dmrs_phaseDifference[m][n]=angle(rx_dmrs_data[m][n](tx_dmrs_data[m][n]) * ) Among them: represents dot product; () * Indicates conjugate calculation; angle() means taking the phase angle of all members; Step C4: The reference signal phase difference matrix dmrs_phaseDifference[m][n] is averaged in the frequency domain to obtain the reference signal phase difference array: Where: "M" represents the number of subcarriers occupied by the reference signal; Step C5: Assuming the reference signal phase difference array dmrs_phaseAvgDifference[n], calculate the average value Δθ of the phase differences between adjacent reference signals. The calculation formula is: Where: "l" represents the number of OFDMs carrying reference signals; Step C6: Calculate the frequency deviation according to the phase difference Δθ caused by the two adjacent reference signals during the transmission process, and then perform frequency deviation compensation on the power wireless private network frame data rx_TimeSync_waveform to obtain the power wireless private network frame data rx_fine_waveform(n). The calculation formula is: Wherein: Δf is the frequency deviation value; T is the time interval between two reference signals.

6. The method for mapping PDSCH physical channel resources in a power wireless private network according to claim 1, characterized in that: The channel estimation and equalization process specifically includes the following steps: Step D1: The receiving end receives the time domain signal waveform, recorded as rx_waveform(n), and after timing and frequency adjustment, recorded as rx_fine_waveform(n), performs OFDM demodulation on the signal to obtain the power wireless private network resource grid; according to the 230MHz PDSCH resource block mapping rule, the spectrum of the power wireless private network resource grid occupied by the 230MHz PDSCH is non-continuously distributed; Step D2: taking a 230 MHz PDSCH resource block from the power wireless private network resource grid, dividing the 230 MHz PDSCH resource block into a plurality of 230 MHz PDSCH sub-resource blocks, and defining a 230 MHz PDSCH resource occupying consecutive subcarriers as a sub-resource block; Step D3: Assume that the reference channel and data in a 230MHz PDSCH sub-resource block are rx_fine_dmrs and rx_fine_data respectively. The demodulation reference signal of the local 5GNR PDSCH of this sub-block is recorded as tx_dmrs_data, which is used for least squares channel estimation. The calculation process is: H LS =(X H X) -1 X H Y=X -1 Y The corresponding LS channel estimation on each subcarrier is expressed as: Wherein, X[k] is the local reference signal tx_dmrs_data; Y[k] is the received reference signal rx_fine_dmrs; k is the subcarrier number; N is the number of demodulation reference signals in each OFDM symbol; Step D4: Channel estimation result H of 230MHz PDSCH sub-resource block LS [k], k=0,1,...,N-1, in the frequency domain, it is a discrete non-continuous state, and the linear interpolation method is used. The calculation process is: Among them, H[k j ] is the interpolated channel estimate, k j Located in k a With k b Between; H LS [k a ] and H LS [k b ] is the known value of LS channel estimation; Step D5: Using the channel estimation matrix H, adopt the MMSE equalizer weight matrix After completing channel equalization on the received signal rx_fine_data, the PDSCH sub-block data is obtained. The calculation process is: X[k]=W[k]Y[k],k=0,1,...,N-1 Among them, X[k] is the PDSCH sub-block data after equalization; Y[k] is the PDSCH sub-block data rx_fine_data before equalization; N is the PDSCH sub-block data size; express Step D6: Using the same principle, all 230MHz PDSCH sub-resource blocks in the 230MHz PDSCH resource block are channel estimated and equalized, and the data in all PDSCH sub-resource blocks are equalized and spliced ​​into a complete 5GNR PDSCH data block, and finally the 5GNR channel decoding process is performed.

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