A power wireless private network PDSCH physical channel resource mapping method

Abstract

The present application relates to a kind of power wireless private network PDSCH physical channel resource mapping method, belong to wireless communication technical field, the present application is according to the allocation mode of OFDM symbol, subcarrier in standard 5GNR PDSCH, redesign 5GNR PDSCH mapping to the resource mapping of power wireless private network, form power wireless private network resource grid, and just the discrete PDSCH resource block after remapping, corresponding timing synchronization, frequency synchronization and channel estimation and equalization method are proposed, meet 5GNR PDSCH resource can be transmitted in power wireless private network requirement, and improve the spectral utilization efficiency and system anti-interference ability.

Description

Technical Field

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

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

[0003] 1. Bandwidth limitation and spectrum distribution discreteness

[0004] The 230MHz band has a total bandwidth of only approximately 10MHz, with limited sub-band width (25kHz), widely spaced sub-bands, and highly discrete resource distribution. This limits communication capacity and increases the complexity of multi-carrier signal design. Furthermore, industry-wide 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 5G NR frame structure is designed for continuous bandwidth in mid- and high-frequency bands, with a subcarrier spacing of 15kHz or an integer multiple thereof. However, the 230MHz band resource block bandwidth is 25kHz, creating a mismatch. Furthermore, the continuous spectrum assumption of 5G is not applicable to discrete spectrum scenarios, making traditional scheduling algorithms difficult to directly apply.

[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 5GNR PDSCH (Physical Downlink Shared Channel) is a transmission channel that carries end-user (UE) data. It is a key channel for delivering actual content to users. However, deploying the 5GNR PDSCH in a resource grid 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 can correctly demodulate PDSCH.

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

[0013] In the power wireless private network resource grid, timing deviation has a particularly significant impact on PDSCH demodulation. Due to the discrete spectrum distribution and narrow bandwidth of power wireless private network frequency bands (such as 230 MHz), accurate timing synchronization becomes even more critical. In this resource grid, timing deviation can cause the start position of the OFDM symbol to be out of sync with the FFT window, disrupting the orthogonality between subcarriers and leading to inter-symbol interference (ISI) and inter-carrier interference (ICI). Specifically, the PDSCH mapping scheme must adapt to the discrete nature of the spectrum. Any timing offset will increase interference between different subbands, further impacting signal demodulation performance. Furthermore, due to the large number of subcarriers in this resource grid, timing deviation has a more significant impact on the data phase rotation on the subcarriers, thereby changing the constellation shape and increasing the bit error rate. In the power wireless private network environment, if timing deviation exceeds the cyclic prefix (CP) length, it will not only cause intra-symbol interference but may also introduce information from 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 crucial to ensuring the integrity and demodulation performance of PDSCH signals.

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

[0015] Frequency deviation significantly impacts PDSCH demodulation mapped to the power wireless private network resource grid. Due to the discrete spectral distribution of the power wireless private network resource grid, frequency deviation (carrier frequency offset, CFO) causes each subcarrier of the received signal to deviate from its ideal frequency, resulting in phase rotation in the frequency domain. This offset further amplifies the orthogonality between subcarriers within the resource grid, leading to inter-subcarrier interference (ICI) and inter-symbol interference (ISI). The narrow and discrete bandwidth and subband spacing of resource blocks in power wireless private networks complicate and significantly impact the interference caused by frequency deviation. Specifically, the discrete resource distribution can cause interference to spread across multiple subbands, further degrading demodulation performance and significantly reducing the signal-to-noise ratio (SNR). Frequency deviation can also cause interference superposition between different subbands, making signal differentiation more difficult and leading to increased bit error rates. In extreme cases, frequency deviation can make it difficult to distinguish between signals and noise, directly impacting the effective transmission of PDSCH. Therefore, accurate frequency synchronization is crucial for ensuring PDSCH demodulation performance within the power wireless private network resource grid and is a key technology for ensuring communication reliability and data transmission quality.

[0016] Fourth: 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, directly impacting demodulation performance. In power wireless private networks, due to the discrete spectrum resources and narrow bandwidth, accurate channel estimation is particularly important, as it determines whether the impact of the wireless channel on the transmitted signal can be effectively compensated. In this specific resource grid structure, PDSCH still uses Demodulation Reference Signals (DMRS), similar to those used in 5G NR, for channel estimation to aid in demodulation of the physical channel. However, due to the discrete spectrum distribution and uneven subband spacing in power wireless private networks, traditional channel estimation methods may not be fully adapted to the new resource grid structure. Inaccurate channel estimation will significantly degrade the demodulated signal quality, manifesting as increased inter-symbol interference (ISI) and inter-carrier interference (ICI), thereby increasing the bit error rate (BER). Channel equalization is a further compensation step for the channel estimation results, helping to recover the signal after channel fading and interference. If channel equalization fails to fully account for the discrete spectrum characteristics of power wireless private networks, it may not effectively suppress these interferences, thus affecting data transmission reliability 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 spectrum resource discontinuity, and designing appropriate 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 power wireless private network PDSCH.

[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 demodulated using the 5GNR PDSCH link to obtain the transmitted PDSCH data block;

[0023] Process 2: Timing synchronization: The demodulation reference signal in the 230MHz PDSCH resource block is retained and its data portion is reset to zero to form a receive reference signal data block. The demodulation reference signal in the local PDSCH is mapped to the power wireless private network resource grid using the transmitter's demodulation reference signal mapping method to form a local reference signal data block. The receive reference signal data block and the local reference signal data block are then conjugate-point-multiplied and summed in the frequency domain to obtain a frequency-domain correlation array of the demodulation reference signal. This array is then inverse-fast Fourier transformed (IFFT) into a time-domain impulse array. The position of the maximum value is the timing synchronization position.

[0024] Process 3: Frequency synchronization: First, the phase difference between the received and local reference signal data blocks is calculated. The phase difference between adjacent demodulated reference signals is used to estimate the magnitude of the frequency offset and 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. For each 230MHz PDSCH sub-resource block, the channel matrix and noise variance are calculated using the least squares method based on the local demodulation reference signal. The equalizer weight matrix is ​​then calculated using the minimum mean square error (MMSE). The received signal is input into the equalizer for equalization. Finally, the equalization results of all 230MHz PDSCH sub-resource blocks are spliced ​​into a complete 5GNR PDSCH modulated data block.

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

[0027] Step A1: The PDSCH data block is scrambled, coded, 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 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. The power wireless private network resource grid is 4096×20, representing 4096 subcarriers and 20 orthogonal frequency division multiplexing (OFDM) symbols. The power wireless private network resource grid can simultaneously carry the 5GNR PDSCH resource blocks of multiple terminals. 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 blocks occupy 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 blocks are 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, occupying 12N subcarriers continuously in the frequency domain; occupying the same number of OFDM symbols continuously in the time domain, and finally mapping the standard 5GNR PDSCH resource block to a 230MHz PDSCH resource block; the power wireless private network resource grid is OFDM modulated 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 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. The 5GNR PDSCH resource block 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 is 1 except for the notch frequency band where the notch is required. 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. This 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. At the receiving end, the time domain signal waveform is received and OFDM demodulated 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.

[0037] Step B2: Perform conjugate point multiplication on the local reference signal data block and the received reference signal data block. Accumulate the conjugate point multiplication results of the corresponding subcarrier positions in the frequency domain to obtain a reference signal frequency domain correlation array. Perform a fast Fourier transform on this array to obtain a time domain impulse 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. The calculation process is as follows:

[0038]

[0039]

[0040] in,() *represents the complex conjugate operation; max() represents the maximum value in an array; abs() represents the 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 positional 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] Furthermore, the frequency synchronization process includes the following steps:

[0045] Step C1: 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. Based on the corresponding position of the 230 MHz PDSCH resource block in the power wireless network, the reference signal data on each OFDM is extracted to form the received reference signal data, recorded as rx_dmrs_data[m][n], where the subscript m represents the reference signal number on the carrier and n represents the OFDM symbol number.

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

[0047] Step C3: 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], calculated as follows:

[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: Perform an average calculation on the reference signal phase difference matrix dmrs_phaseDifference[m][n] in the frequency domain to obtain the reference signal phase difference array:

[0051]

[0052] Where: "M" represents 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 OFDM frames carrying reference signals;

[0056] Step C6: Calculate the frequency offset based on the phase difference Δθ caused by the transmission of two adjacent reference signals. Then, perform frequency offset compensation on the power wireless network frame data rx_TimeSync_waveform to obtain the power wireless 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 the two reference signals.

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

[0060] Step D1: The receiver receives the time-domain signal waveform, denoted as rx_waveform(n), adjusts the timing and frequency, and denoted as rx_fine_waveform(n). The signal is then demodulated by OFDM to obtain the power wireless private network resource grid. According to the 230 MHz PDSCH resource block mapping rules, the spectrum occupied by the 230 MHz PDSCH in the power wireless private network resource grid is distributed discontinuously.

[0061] Step D2: Take out 230MHz PDSCH resource blocks from the power wireless private network resource grid, divide the 230MHz PDSCH resource blocks into multiple 230MHz PDSCH sub-resource blocks, and define the 230MHz PDSCH resource occupying continuous subcarriers as a sub-resource block;

[0062] Step D3: Assuming that the reference channel and data in a 230MHz PDSCH sub-resource block are rx_fine_dmrs and rx_fine_data respectively, the sub-block is denoted as tx_dmrs_data in the local 5GNR PDSCH demodulation reference signal, which is used for least square channel estimation, and the calculation process is as follows:

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

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

[0065]

[0066] Where 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: The channel estimation result H LS [k], k = 0, 1,..., N-1 of the 230MHz PDSCH sub-resource block is in discrete and non-continuous state in the frequency domain, and the linear interpolation method is used, and the calculation process is as follows:

[0068]

[0069] Where H[k j ] is the interpolated channel estimation value, k j is located between k a and k b ; H LS [k a ] and H LS [k b ] are known values of LS channel estimation;

[0070] Step D5: Using the channel estimation matrix H, the MMSE equalizer weight matrix After channel equalization of the received signal rx_fine_data, the PDSCH sub-block data is obtained, and the calculation process is as follows:

[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 then 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 deployment in power wireless private networks, the present invention proposes a wireless resource allocation method for 5GNR PDSCH adaptation to power wireless private networks. According to the allocation method of OFDM symbols and subcarriers in the standard 5GNR PDSCH, the resource mapping of 5GNR PDSCH to the power wireless private network is redesigned to form a power wireless private network resource grid. In addition, corresponding timing synchronization, frequency synchronization, channel estimation and equalization methods are proposed for the discrete PDSCH resource blocks after remapping. This meets the requirements for 5GNR PDSCH resources to be transmitted in power wireless private networks, and improves spectrum utilization efficiency and system anti-interference capability. The specific advantages are as follows:

[0077] First: The present invention proposes an adaptation scheme for 5GNR PDSCH time-frequency resources and power 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 power wireless private network time domain resource grid uses 20 OFDM symbols as the unit. 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 power 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 in the frequency domain subcarrier, the method provided by the present invention is used to recombine the demodulation reference signals in the discrete 230MHz PDSCH, and still obtain a perfect precision synchronization solution.

[0079] Third, this invention proposes a fine frequency synchronization scheme for the PDSCH in the power wireless private network. Standard 5GNR PDSCH resources are mapped to the 230MHz frequency band, forming a 230MHz PDSCH resource block. At the receiving end, the demodulation reference signal is extracted from the 230MHz PDSCH resource block and the phase difference between two adjacent OFDM symbols is calculated. The local demodulation reference signal and the phase difference between two adjacent OFDM symbols are then used to perform fine frequency synchronization.

[0080] Fourth, this invention provides a channel estimation and equalization solution for the PDSCH in the power wireless private network. At the receiving end, the 230 MHz PDSCH resource block is first divided into multiple small PDSCH resource blocks during channel estimation and equalization, as the frequency domain resources are discontinuous. These PDSCH resource blocks occupy consecutive subcarriers that are integer multiples of 12. Channel estimation and equalization are then performed independently for each block, thus mitigating performance losses caused by the discontinuous subcarrier occupation of the 230 MHz PDSCH.

[0081] Other advantages, objects, and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art upon examination of the following description or may be learned from practice of the present invention. The objects and other advantages of the present invention may 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 with reference to the accompanying drawings, in which:

[0083] Figure 1 This is a diagram of the 5GNR PDSCH transmission process 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 accurately and adjust the flow chart;

[0086] Figure 4 It is a flowchart of frequency fine synchronization and adjustment;

[0087] Figure 5 Figure 2 is a diagram of the channel estimation and channel equalization process for PDSCH;

[0088] Figure 6 The simulation and verification block diagram for the PDSCH receive and transmit links;

[0089] Figure 7 Figure 2 is the time-frequency resource diagram for PDSCH transmission and reception under the 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] Figure 9 (a) to (l) show 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] Figure 10 Schematic diagram of remapping the time and frequency resources of the power wireless private network into 5GNR PDSCH resource blocks;

[0093] Figure 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] Figure 12 Figure 2 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] Figure 13 Schematic diagram of the demodulation performance of the PDSCH data block TBData, where (a) is the PDSCH transmission accuracy rate; (b) is the bit error rate of the PDSCH data block TBData;

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

[0097] Figure 15 Figure 3 is the time-frequency resource diagram of the transmitter and receiver under the chirp interference in 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] Figure 16 The Bode diagram corresponding to the notch filter at the positions corresponding to the center subcarriers 496 and 556 is shown;

[0099] Figure 17 Figure 3 is the time-frequency resource diagram of the transmitter and receiver of chirp interference under the 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] Figure 18 Timing and frequency synchronization performance with a timing offset of 107 and a frequency offset of 100 Hz in the presence of chirp interference in the CDL channel, where (a) is frequency synchronization and (b) is timing synchronization.

[0101] Figure 19 Figure 2 is 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] Figure 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 present application is illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which: BRIEF DESCRIPTION OF THE DRAWINGS

[0104] It is to be understood that the figures of the embodiments provided in the following description are for illustration of the basic concepts of the present application only and not for explaining any specific structure, shape, and size of the components in actual implementation, and the actual implementation of the components can be a random change in shape, number, and proportion, and the layout pattern of the components can be more complex.

[0105] In the following description, numerous specific details are discussed in order to provide a thorough explanation of embodiments of the present application. It will be apparent, however, to one of ordinary skill in the art that embodiments of the present application can be practiced without these specific details. In other instances, well-known structures and devices are not described in detail in order to avoid obscuring embodiments of the present application.

[0106] As shown in Figure 1 The present application provides a power wireless private network PDSCH physical channel resource mapping method, which consists of two parts, PDSCH sending part and PDSCH receiving part. The PDSCH sending part consists of 5GNR PDSCH channel coding and 230MHz PDSCH resource mapping. The PDSCH receiving part consists of interference filtering, 230MHz PDSCH resource demapping, timing synchronization, frequency synchronization, channel estimation and equalization, 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 block, scrambling, code block segmentation, LDPC (Low-Density Parity-Check Coding) coding, rate matching and modulation mapping, and PDSCH resource mapping. After the PDSCH data block at the sending end is processed by this module, the 5GNR PDSCH modulation data block is obtained, which is combined with the demodulation reference signal and mapped into the standard 5GNR PDSCH resource block, which includes data and demodulation reference signal (DMRS for short).

[0108] 230MHz PDSCH resource mapping: Standard 5GNR PDSCH resource blocks are mapped to the power wireless private network resource grid (4096×20) to form a 230MHz PDSCH resource block. When mapping standard 5GNR PDSCH resource blocks, the power wireless private network resource grid can only carry a single terminal's standard 5GNR PDSCH resource block. However, multiple terminal standard 5GNR PDSCH resource blocks can be transmitted simultaneously in the same power wireless private network resource grid, occupying different subcarriers and OFDM symbols. When allocating power wireless private network resources, the network prioritizes resource blocks with the most contiguous subcarriers to carry PDSCH transmissions. 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 2.5 kHz subcarriers and 20 OFDM symbols, but it can be used non-contiguously in the frequency domain. Some 25 kHz subbands are used by other systems, known as interference subbands. When the 5G NRPDSCH resource block is mapped to the power wireless private network resource grid, the interference subbands must be filtered out of the 230 MHz PDSCH resource block. In this invention, a notch filter is used to remove the interference subbands. The notch filter's center frequency is the center frequency of the 25 kHz interference subband.

[0110] 230MHz PDSCH resource demapping: Receive the airborne power wireless private network frame data, remove the interference subband through the interference filter, perform OFDM demodulation, and obtain the power wireless private network resource grid. According to the transmitter, the time-frequency resource position of the 230MHz PDSCH resource block is determined, and the 5GNR PDSCH resource block is taken out of 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, and set all its data parts to zero to 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 transmitter's demodulation reference signal mapping method to form a local reference signal data block. The received reference signal data block and the local reference signal data block are then conjugate point multiplied and summed in the frequency domain to obtain the demodulation reference signal frequency domain correlation array. The array is transformed into a time domain impulse array by inverse fast Fourier transform (IFFT for short). The position of the maximum value is the timing synchronization position.

[0112] Frequency synchronization: Within the received reference signal block and the local reference signal block, at least two OFDM symbols contain demodulation reference signals. The phase difference between the received and local reference signal blocks is calculated. Using the phase difference between adjacent demodulation reference signals, the frequency offset is estimated to achieve 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. For each 230MHz PDSCH sub-resource block, the channel matrix and noise variance are minimized using the least squares (LS) method based on the local demodulation reference signal. The equalizer weight matrix is ​​then calculated using the minimum mean square error (MMSE). The received signal is then input into the equalizer for equalization. Finally, the equalization results of all 230MHz PDSCH sub-resource blocks are concatenated into a complete 5GNR PDSCH modulated data block.

[0114] 5GNR PDSCH channel decoding: The PDSCH channel decoding chain for the power wireless private network consists of the standard 5GNR PDSCH channel decoding chain, which includes demodulation, rate matching, LDPC decoding, code block reassembly, descrambling, and parity checking. This module processes the 5GNR PDSCH modulated data block to produce the PDSCH data block.

[0115] In terms of the process, the present invention has a total of 4 processes, namely process 1: PDSCH channel encoding and decoding and resource mapping process; process 2: timing synchronization process; process 3: frequency synchronization process; process 4: 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 for the power wireless private network is fully compatible with the standard 5GNR PDSCH channel coding process. According to the standard 5GNR PDSCH channel coding definition, the PDSCH data block is scrambled, coded, LDPC-encoded, rate-matched, and modulated to form a 5GNR PDSCH modulated data block. This is then mapped along 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 some or all of the time-frequency resources based on the transmission PDSCH resource requirements. In the power wireless network, the power wireless network radio frame is 10ms long and consists of 20 OFDM symbols. The power wireless network radio frame can carry the 5GNR PDSCH resource blocks of a terminal or multiple terminals at the same time. These resource blocks occupy different time-frequency resources in the power wireless network resource grid.

[0119] Step 3: Standard 5GNR PDSCH resource blocks occupy time-frequency resources in physical resource blocks (PRBs). Each PRB contains 12 contiguous subcarriers, which embed the demodulation reference signal. The time-frequency resource grid of the power wireless private network is a discrete distribution of subcarrier resources, with non-contiguous subcarrier resource blocks. The 5GNR PDSCH resource blocks are remapped to fit 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, occupying 12N consecutive subcarriers (N is a positive integer) in the frequency domain. Unusable 25 kHz subbands may exist within these 12N subcarriers. In the time domain, the same number of consecutive OFDM symbols is occupied, ultimately mapping the standard 5GNR PDSCH resource block to a 230 MHz PDSCH resource block. The power wireless private network resource grid undergoes OFDM modulation to produce the power wireless private network frame data.

[0121] Step 5: At the receiving end, the received power wireless network frame data is interference filtered and OFDM demodulated to obtain the power wireless network resource grid. According to the standard 5GNR PDSCH resource block mapping rules of the transmitting end, the 230MHz PDSCH resource block is extracted from the power wireless network resource grid and remapped to obtain the 5GNR PDSCH resource block. The 5GNR PDSCH resource block 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. 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: The demodulation reference signal in the local standard 5G NR PDSCH resource block is remapped into the power wireless private network resource grid (4096x20), which only carries the local demodulation reference signal, and other time-frequency resources are all set to zero, forming a local reference signal data block. When receiving the time domain signal waveform, OFDM demodulation is performed to obtain the power wireless private network resource grid, in which only the demodulation reference signal corresponding to the 5G NR PDSCH is retained, and other parts are set to zero to form a received reference signal data block.

[0124] Step 2: The local reference signal data block and the received reference signal data block are multiplied by the conjugate point to calculate the conjugate point multiplication result corresponding to the subcarrier position in the frequency domain, and the reference signal frequency domain correlation array is obtained by accumulating the conjugate point multiplication result. The fast Fourier transform is performed on the array to obtain the time domain impact array, and the position of the maximum value is the timing synchronization position, that is, the timing synchronization point d of the power wireless private network frame data, as shown in Figure 3 The calculation process is as follows:

[0125]

[0126]

[0127] Wherein, "() * " represents complex conjugate operation; "max()" represents taking the maximum value in the array; "abs()" represents modulus 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 fast inverse Fourier transform; pdsch_dmrs_C(d) is the correlation value when d timing offset; d is the position deviation of the received and local reference signal data blocks.

[0128] Step 3: According to the timing synchronization position d, the received signal is compensated, and the calculation process is as follows:

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

[0130] Wherein, rx_waveform represents the received power wireless private network frame data; and rx_TimeSync_waveform represents the power wireless private network frame data after timing fine synchronization.

[0131] Process three: frequency synchronization process, the overall steps are as shown in Figure 4

[0132] ​Step 1: At the receiver, the timing-compensated power wireless network frame data (rx_TimeSync_waveform) is demodulated using OFDM to obtain the power wireless network resource grid. Based on the corresponding position of the 230 MHz PDSCH resource block in the power wireless network, the reference signal data on each OFDM is extracted to form the received reference signal data, denoted as rx_dmrs_data[m][n], where the subscript m represents the reference signal number on the carrier and n represents the OFDM symbol number.

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

[0134] Step 3: Perform conjugate dot 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: Perform an average calculation on the reference signal phase difference matrix dmrs_phaseDifference[m][n] in the frequency domain to obtain a reference signal phase difference array.

[0138]

[0139] Where: “M” represents 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 differences between adjacent reference signals. Calculation formula:

[0141]

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

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

[0144]

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

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

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

[0148] Step 2: Take 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] Where 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; and 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, is a discrete and discontinuous state in the frequency domain. 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 the known value of 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 MATLAB simulation examples to further illustrate the data transmission method of the present invention in the power wireless private network system.

[0163] Process one: PDSCH receiving and transmitting chain and mapping process of nr230Redcap

[0164] This embodiment uses MATLAB for simulation verification, simulates the sending and receiving process of a frame (10 milliseconds, 10 ms) of PDSCH data of the power wireless private network. According to the content of the present application, the parameters of the simulation setting in this embodiment are shown in Table 1. Table 2 provides the resource blocks that can be used by the power wireless private network, in which the unusable 15KHz subband and the subcarrier resource that cannot constitute 12 consecutive integers have been proposed.

[0165] Table 1

[0166]

[0167] Table 2

[0168]

[0169] The specific verification link block diagram is shown in Figure 6

[0170] In this verification link, the standard 5G NR PDSCH resource block is denoted as tx5gNrGrid, which occupies 14 consecutive OFDM symbols in the time domain resource and 12x50 = 600 consecutive subcarriers in the frequency domain resource. The DMRS in tx5gNrGrid occupies OFDM symbol positions 2, 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), the code rate is 0.478, the layer mapping number is 2; the number of transmitting antennas is 2, and the number of receiving antennas is 2.

[0171] ​The MATLAB simulation platform was used to verify the transmission link of tx5gNrGrid in the power wireless private network resource grid. In this embodiment, tx5gNrGrid was 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 was modulated by OFDM to form power wireless private network frame data, recorded as txWaveform. txWaveform was simulated through the NR channel (CDL) and output power wireless private network frame data, recorded as rxWaveform. rxWaveform was demodulated by OFDM to form a power wireless private network resource grid, recorded as rxNr230Grid. Then, through process 2 of this embodiment, timing synchronization, frequency synchronization, channel estimation and equalization were completed, and the data was spliced ​​into a complete 5G NRPDSCH modulated data block, recorded as rx5gNrBurstGrid. After completing the PDSCH channel decoding and post-processing, the PDSCH data block was obtained, recorded as TBData.

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

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

[0174] Note: This step fully demonstrates 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, as shown in the following example: 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.

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

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

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

[0179] Note 2: The tx5gNrGrid resource block and the tx230PdschGrid resource block carry the same content, but the subcarriers in the tx5gNrGrid resource block are continuously allocated, while the subcarriers in the tx230PdschGrid resource block may be discontinuous.

[0180] Step 4: The power wireless private network frame data txWaveform passes through the simulation CDL channel. Output the power wireless private network frame data, denoted as rxWaveform, as shown in Figure 9 (g), (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 10240KHz defined in the present application. In the simulation, different signal-to-noise ratios can be selected for PDSCH channel decoding performance evaluation. This step fully proves the feasibility of 2.5KHz subcarrier spacing in actual 5G NR channel transmission.

[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), denoted as rxNr230Grid. Using the local reference signal data block (4096x20x2), denoted as refDMRSGrid, timing synchronization is completed, and the timing offset Timingoffset is calculated. The received signal rxWaveform is compensated for timing offset to form the power wireless private network frame data, denoted as rxTimeSyncWaveform.

[0182] Note: The rxNr230Grid resource block at the receiving end and the txNr230Grid resource block at the transmitting end are defined identically.

[0183] Step 7: OFDM demodulates the timing-compensated rxTimeSyncWaveform to form the power wireless network resource grid, denoted as rxTimeSyncNr230Grid. Frequency synchronization is performed using the local reference signal data block refDMRSGrid. The frequency offset Freqoffset is calculated and frequency offset compensation is performed on the received signal rxTimeSyncWaveform to form the power wireless network frame data, denoted as rxFreqSyncWaveform.

[0184] Step 8: Perform OFDM demodulation on the frequency compensated rxFreqSyncWaveform. The power wireless network resource grid is recorded as rxNr230Grid. Figure 10 The mapping process shown in the figure maps the rxNr230Grid into the rx5gNrBurstGrid resource block. Using the refDMRSGrid, the channel estimation and equalization are completed in the PDSCH sub-block mode, and then the complete 5GNR PDSCH modulated data block is spliced. After the PDSCH channel decoding is completed, 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 and perform OFDM demodulation 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 rest is reset to zero to form a receive reference signal data block (4096x20x2), recorded as rxDMRSGrid.

[0190] Step 3: Perform conjugate dot product calculations on refDMRSGrid and rxDMRSGrid. Accumulate the conjugate dot product results at the corresponding subcarrier positions in the frequency domain. Take the average of the third dimension to obtain the reference signal frequency domain correlation array. Perform a fast Fourier transform on this array to obtain the time domain impulse array. Find the position of the maximum value, which is the timing offset Timingoffset of the power wireless private network frame data:

[0191]

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

[0193] Step 4: At the receiver, the timing-compensated power wireless network frame data (rxTimeSyncWaveform) is demodulated using OFDM to generate the power wireless network resource grid (rxTimeSyncNr230Grid). Based on the corresponding position of the 230 MHz PDSCH resource block (tx230PdschGrid) in the power wireless network, the reference signal data on each OFDM is extracted to form the received reference signal data (300x2x2), rxTimeSyncDMRSGrid.

[0194] Step 5: According to the rules for generating 5GNR PDSCH demodulation reference signals at the transmitter, the same 5GNR PDSCH demodulation reference signals are generated at the receiver to form local reference signal data (300×2×2), which is recorded as refTimeSyncDMRSGrid.

[0195] Step 6: Perform conjugate dot multiplication on the received reference signal data rxTimeSyncDMRSGrid and the local reference signal data refTimeSyncDMRSGrid, then take the mean of the third dimension to obtain the phase difference matrix (300×2) between the received and local reference signals, 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 the 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] Where: “1” represents the number of OFDM frames carrying reference signals, which is 2.

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

[0205]

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

[0207] When the subcarrier spacing (SCS) is 2.5 kHz, the frequency offset estimation range in this example is:

[0208]

[0209]

[0210]

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

[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 this sub-block in the local 5GNR PDSCH is denoted as refDMRAData and used for least squares (LS) channel estimation. The calculation process is:

[0214]

[0215] Step 13: Channel estimation result H for 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, the linear interpolation method is used. The calculation process is:

[0216]

[0217] Among them, H[k j ] is the interpolated channel estimation value, 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.

[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] wherein X[k] is the equalized PDSCH sub-block data, denoted as rxMMSEFineDATA; Y[k] is the pre-equalized PDSCH sub-block data rxFineDATA; N is the PDSCH sub-block data size; denotes

[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 modulation data block (600x14x2), and finally a 5GNR channel decoding process is performed to complete the PDSCH channel decoding post-processing to obtain the PDSCH data block, denoted as TBData.

[0223] Scenario 1: Timing, frequency synchronization and channel estimation and equalization on PDSCH channel decoding under the condition of no interference sub-band 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, a Clustered Delay Line (CDL) channel model is used for simulation. The CDL channel model can simulate the multipath propagation characteristics of signals in real environments, increasing the realism and complexity of the simulation. In this embodiment, Table 1 lists the parameter configurations 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 a discrete manner in the power wireless private network resource grid, strictly following the spectrum resource configuration requirements of the resource grid. At these subcarrier positions, no other signal interference occurs, thereby 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 the Monte Carlo method is used to complete 500 simulations to verify the stability of the signal performance under the CDL channel.

[0226] Figure 11 The frequency synchronization and timing synchronization performance of the present application under the CDL channel condition are demonstrated, further verifying the effectiveness and robustness of the proposed method in complex channel environments.

[0227] Figure 11Figure (a) depicts the changing trend of frequency synchronization performance. It can be observed that as the signal-to-noise ratio (SNR) increases, the frequency offset estimate gradually approaches the actual frequency offset value. When the SNR is greater than -20dB, the frequency offset estimate 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 across the entire SNR range, significantly reducing the impact of frequency offset on the system's demodulation performance.

[0228] Figure 11 Panel (b) shows the evaluation results of timing synchronization performance. As can be seen from the figure, when the SNR is below -40dB, the estimated timing offset has some error. However, as the SNR increases, the timing estimation performance improves significantly. When the SNR is above -40dB, the estimated timing offset is completely consistent with the actual timing offset, demonstrating that this method can effectively compensate for the impact of timing offset on the system and ensure the stability of demodulation performance.

[0229] Overall, the performance differences between the frequency and timing synchronization modules under CDL channel conditions demonstrate the impact of channel characteristics on synchronization accuracy. However, thanks to the proposed method's comprehensive modeling and compensation strategy for complex channel characteristics, the system maintains high frequency and timing synchronization performance even in challenging multipath channel environments, providing a solid foundation for reliable demodulation of PDSCH signals.

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

[0231] Figure 12 Figures (a) and (c) show the QPSK constellation diagrams of the PDSCH signal before channel equalization for two receiving antennas in a CDL channel environment. From the figures, we can see that the constellation point distribution of the received signal has a small phase rotation compared to the ideal case. Figure 12 (e) shows the distribution of the bit log-likelihood ratio (LLR) under CDL channel conditions, which shows 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. Figure 12Figures (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, Figure 12 Figure (f) shows the log-likelihood ratio (LLR) results after equalization. Compared to before equalization, the LLR distribution is clearer and closer to the ideal demodulated value, indicating that the channel equalization module significantly improves the signal's soft decision performance, thereby enhancing the PDSCH bit error rate performance.

[0233] In summary, the proposed 5GNR PDSCH resource block mapping scheme, combined with channel estimation and equalization modules, demonstrates superior demodulation performance under CDL channel conditions. Channel equalization not only effectively compensates for signal phase and amplitude deviations but also enhances soft decision accuracy, providing a technical guarantee for reliable communication under low signal-to-noise ratio conditions.

[0234] Figure 13 The data is comprehensively displayed on the PDSCH data block transmission performance under different signal-to-noise ratio (SNR) conditions, including the changing trends of successful transmission rate (Throughput) and bit error rate (BER), which deeply reflects the transmission characteristics of the system in complex channel environments.

[0235] Figure 13 Figure (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] Figure 13Figure (b) further analyzes the PDSCH bit error rate (BER) as it changes with SNR. Under low SNR conditions, where the SNR is below -30dB, the BER is high, indicating that under these conditions, noise has a significant impact on the received signal, and the channel equalization and demodulation schemes cannot completely eliminate errors. However, as the SNR increases, the BER decreases rapidly. When the SNR reaches -30dB, the BER drops to zero and remains zero error thereafter. This demonstrates that, in low SNR environments, the channel equalization module effectively eliminates errors in the signal caused by multipath fading and noise interference, ensuring the integrity and transmission reliability of the PDSCH data blocks.

[0237] In summary, Figure 13 This study validates the effectiveness of the proposed 5GNR PDSCH resource block transmission scheme in complex channel environments. The demodulation scheme demonstrates robustness and reliability in both transmission success rate and bit error rate performance, providing strong technical support and performance assurance 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 a 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 chirp bandwidth generated by the simulation 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. Figure 14 shown.

[0240] In this scenario, to evaluate the impact of the chirp signal on the PDSCH channel decoding performance, the chirp signal is configured to occupy the subcarrier positions 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 chirp signal overlaps with the PDSCH signal in terms of spectrum distribution, it directly interferes with the PDSCH data block and DMRS (Demodulation Reference Signal) signal, thereby affecting the demodulation performance of the PDSCH signal and the transmission quality of the system.

[0241] Figure 15 (c) andFigure 15 Figure (d) shows the spectrum and time domain performance of the PDSCH signal when it is interfered with by chirps. It can be observed that, due to its significant power and wide spectrum, the chirp signal not only covers the target frequency band but also severely obscures the PDSCH signal. Especially at high power, the effective information of the PDSCH signal is almost completely submerged. This shows that when chirps are not properly processed, their interference effect on the PDSCH signal is significant and cannot be ignored.

[0242] To mitigate the interference effects of chirp signals, this study proposes a signal interference suppression method based on a notch filter. During the PDSCH demodulation process, a notch filter is introduced at the receiver to precisely filter the frequency band occupied by the chirp signal, significantly reducing its interference on the PDSCH subcarriers. This method not only effectively reduces the interference strength of the chirp signal but also ensures that the PDSCH signal maintains high integrity and reliability during the demodulation process, thereby evaluating the system's robustness and anti-interference performance under interference conditions.

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

[0244] Due to the presence of 25kHz bandwidth interference sub-band signals such as chirps and FSK signals, which occupy the 230MHz frequency band, the spectrum spread of these interference signals seriously affects PDSCH demodulation. According to the present invention, this embodiment now uses a notch filter. By setting the corresponding filter parameters, it can filter out interference signals within the specified frequency band to ensure normal PDSCH demodulation.

[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, the amplitude gain is 0 at the notch frequency band, and the amplitude gain of other frequency bands is 1. This means that except for the frequency signal that will attenuate the interference signal, other frequency signals will remain unchanged. Figure 16 The Bode diagram corresponding to the Chirp and FSK interference signals with a bandwidth of 10 MHz is shown in the figure. 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 Figure 17 As shown in (c)-(d). Figure 17Figures (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] Figure 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 complex communication environments are verified.

[0250] Figure 18 (a) depicts the changing trend of frequency synchronization performance. It can be observed that as the signal-to-noise ratio (SNR) increases, the frequency offset estimate gradually approaches the actual frequency offset value. However, due to the interference of chirp signals, the frequency synchronization performance degrades compared to Scenario 1 across the entire SNR range. Despite this, the proposed method still effectively improves the impact of frequency offset on the system across the entire SNR range, demonstrating that the scheme can significantly reduce the impact of frequency offset on the system's demodulation performance.

[0251] Figure 18 Panel (b) shows the evaluation results of timing synchronization performance. As can be seen from the figure, the signal is interfered with by the chirp signal, so the timing synchronization performance degrades compared to Scenario 1 in the low SNR range. However, the proposed method can still accurately complete timing synchronization and effectively compensate for the impact of timing offset on the system under relatively high SNR conditions.

[0252] Figure 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] Figure 19 (a) and Figure 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 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, Figure 19 (e) shows the bit log-likelihood ratio (LLR) distribution when no equalization is performed. It can be observed that it exhibits large dispersion and is far 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: Figure 19 (b) and Figure 19 As shown in (d) in the figure. Although the equalization effect is slightly affected compared to 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, Figure 19 As can be seen in (f), the LLR distribution is significantly improved after equalization, closer to the ideal soft decision value, and the distribution concentration is significantly enhanced.

[0255] Figure 20 The results comprehensively demonstrate the transmission performance of PDSCH data blocks in a CDL channel environment with superimposed chirp signal interference, including the trends of successful transmission rate (throughput) and bit error rate (BER) as a function of signal-to-noise ratio (SNR). These results reveal how the system's transmission characteristics vary in an interference environment and verify the applicability and robustness of the proposed solution.

[0256] Figure 20 Figure (a) shows how the PDSCH data block transmission success rate varies with SNR. As the SNR increases, the success rate shows a clear, gradual upward trend. When the SNR is below -30dB, the success rate decreases significantly, indicating that the signal is subject to both chirp interference and noise, significantly increasing the probability of demodulation failure. However, when the SNR exceeds -30dB, the success rate increases rapidly, demonstrating that the demodulation scheme can effectively cope with the effects of noise interference under medium and high SNR conditions. In particular, when the SNR is further increased to a higher level, the transmission success rate approaches 100%, fully verifying the reliability of the proposed method in high SNR environments. Notably, compared to scenario 1, which does not include chirp signal interference, the PDSCH transmission success rate in this scenario is significantly affected under low SNR conditions due to the spectral spread and high power characteristics of the chirp signal. However, due to the addition of the notch filter, the success rate still shows strong resilience in the medium and high SNR range, demonstrating the system's robust transmission performance in complex interference environments.

[0257] Figure 20(b) further analyzes the PDSCH bit error rate (BER) as a function of SNR. When the SNR falls below -30dB, the BER increases significantly, indicating that the combined effects of noise and chirp interference severely damage the amplitude and phase of the received signal, making it difficult for the channel equalization and demodulation scheme to completely eliminate errors. However, as the SNR increases, the BER decreases rapidly. When the SNR reaches -30dB, the BER drops to zero and remains at zero error thereafter. Compared to scenario 1, the chirp interference causes a significant increase in the BER at low SNRs, but the proposed scheme still demonstrates strong error suppression capabilities at higher SNRs. In particular, the rapid convergence of the BER after the SNR exceeds -30dB indicates that the system's demodulation performance has been effectively restored. This also verifies the channel equalization module's ability to compensate for chirp interference and its positive impact on PDSCH demodulation performance.

[0258] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. 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 solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should all 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 by: The following processes are included: Process 1: PDSCH channel encoding and decoding and resource mapping process: At the transmitter, the PDSCH channel is encoded into a 5G NR PDSCH resource block, and then the 5G NR 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 receiver, the discrete power wireless private network 230MHz PDSCH resource block is restored to a standard 5G NR PDSCH resource and demodulated using the 5G NR PDSCH link to obtain the transmitted PDSCH data block; Process 2: Timing synchronization process: retain the demodulation reference signal in the 230MHz PDSCH resource block and set its data portion to zero to form a receive reference signal data block; use the demodulation reference signal in the local PDSCH and map it to the power wireless private network resource grid using the transmitter's demodulation reference signal mapping method 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. 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: First, the phase difference between the received reference signal data block and the local reference signal data block is calculated. The phase difference between adjacent demodulated reference signals is used to estimate the magnitude of the frequency offset and complete frequency synchronization. Process 4: Channel Estimation and Equalization: First, the 230MHz PDSCH resource block in the power wireless private network resource grid is divided into multiple 230MHz PDSCH sub-resource blocks. For each 230MHz PDSCH sub-resource block, the channel matrix and noise variance are calculated by minimizing the error based on the local demodulation reference signal using the least squares method. Then, the equalizer weight matrix is ​​calculated using the minimum mean square error (MMSE). The received signal is input into the equalizer for equalization. Finally, the equalization results of all 230MHz PDSCH sub-resource blocks are spliced ​​into a complete 5G NR PDSCH modulated 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 and decoding and resource mapping process includes: Step A1: The PDSCH data block is scrambled, coded, LDPC encoded, rate matched, and modulated to form a 5G NR PDSCH modulated data block, which is then mapped together with the demodulation reference signal to form a standard 5G NR PDSCH resource block. Step A2: Map the standard 5G NR PDSCH resource block to the power wireless private network resource grid to form a 230MHz PDSCH resource block. The power wireless private network resource grid is 4096×20, representing 4096 subcarriers and 20 orthogonal frequency division multiplexing (OFDM) symbols. The power wireless private network resource grid can simultaneously carry the 5G NR PDSCH resource blocks of multiple terminals. These resource blocks occupy different subcarriers and OFDM symbols in the power wireless private network resource grid. Step A3: The standard 5G NR PDSCH resource blocks occupy time-frequency resources in physical resource blocks (PRBs). 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 grid with non-continuous characteristics between subcarrier resource blocks. The 5G NR PDSCH resource blocks are remapped to adapt to the power wireless private network resource grid. Step A4: Map the standard 5G NR PDSCH resource block to the power wireless private network resource grid, occupying 12N subcarriers continuously in the frequency domain; occupying the same number of OFDM symbols continuously in the time domain, and finally mapping the standard 5G NR PDSCH resource block to a 230MHz PDSCH resource block; the power wireless private network resource grid is OFDM modulated 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 to obtain the power wireless private network resource grid. According to the standard 5G NR 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 5G NR PDSCH resource block. The 5G NR PDSCH resource block 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 5G NR 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, wherein: 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 is 1 except for the notch frequency band where the notch is required. 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 5G NR PDSCH resource block to the power wireless private network resource grid. This 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. At the receiving end, the time domain signal waveform is received and OFDM demodulated to obtain the power wireless private network resource grid. In this resource grid, only the demodulation reference signal corresponding to the 5G NR PDSCH is retained, and the other parts are set to zero to form a received reference signal data block. Step B2: 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 demodulation reference signal frequency domain correlation array; perform fast Fourier transform on the array to obtain the time domain impact array, and the position of the maximum value is the timing synchronization position, which is the timing synchronization point of the power wireless private network frame data. , the calculation process is: in, Indicates complex conjugate operation; max() means taking the maximum value from the array; abs() means modulo calculation; Indicates the number of reference signal OFDM symbols; Indicates receiving a reference signal data block; is the local reference signal data block; IFFT represents inverse fast Fourier transform; for d The correlation value when the timing offset is 0, the timing synchronization point is the position deviation between the received reference signal data block and the local reference signal data block; Step B3: Based on the timing synchronization point , compensate the received signal, the calculation process is: in, Indicates that power wireless private network frame data has been received; Indicates the power wireless private network frame data after timing 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 network frame data after timing synchronization Through OFDM demodulation, the power wireless private network resource grid is obtained; 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 , where the subscript m Indicates the number of the reference signal on the carrier, n Indicates the number on the OFDM symbol; Step C2: According to the rules for generating 5G NR PDSCH demodulation reference signals at the transmitter, the same 5G NR PDSCH demodulation reference signals are generated at the receiver to form local reference signal data, which is recorded as , where the subscript m Indicates the number of the reference signal on the carrier, n Indicates the number on the OFDM symbol; Step C3: Receive reference signal data and local reference signal data , perform conjugate point multiplication to obtain the phase difference matrix between the received reference signal and the local reference signal, recorded as , the calculation formula is: Where: · represents the dot product; represents conjugate calculation; Indicates taking the phase angle for all members; Step C4: Convert the reference signal phase difference matrix , perform average calculation in the frequency domain to obtain the reference signal phase difference array: in Indicates the number of subcarriers occupied by the reference signal; Step C5: Assume that the reference signal phase difference array , calculate the average value of the phase difference between adjacent reference signals , the calculation formula is: in Indicates the number of OFDM frames carrying reference signals; Step C6: Based on the phase difference caused by the transmission of two adjacent reference signals Calculate the frequency deviation and then synchronize the power wireless network frame data after timing synchronization Perform frequency deviation compensation to obtain compensated power wireless network frame data. The calculation formula is: in: is the frequency deviation value; is the time interval between the 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, which is recorded as , after timing and frequency adjustment, recorded as , OFDM demodulates the signal 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; Step D2: extract 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; Step D3: Assume that the received reference signal and data in a 230MHz PDSCH sub-resource block are respectively and , the demodulation reference signal of this sub-block in the local 5G NR PDSCH is recorded as , which is used for least squares channel estimation, the calculation process is: The corresponding LS channel estimation on each subcarrier is expressed as: in, Demodulation reference signal for local 5G NR PDSCH ; To receive the reference signal ; k is the subcarrier number; is the number of demodulation reference signals in each OFDM symbol; Step D4: Channel estimation results for the 230MHz PDSCH sub-resource block , becomes a discrete and discontinuous state in the frequency domain, and uses the linear interpolation method. The calculation process is: in, is the interpolated channel estimate, lie in and between; and Estimate known values ​​for the LS channel; Step D5: Using the channel estimation matrix , using MMSE equalizer weight matrix , for receiving data After completing channel equalization, the PDSCH sub-block data is obtained. The calculation process is: in, is the PDSCH sub-block data after equalization; PDSCH sub-block data before equalization ; 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. The data in all PDSCH sub-resource blocks are equalized and then spliced ​​into a complete 5G NR PDSCH data block. Finally, the 5G NR channel decoding process is performed.

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