Efficient wireless data transmission optimization method and system

Abstract

The invention discloses an efficient wireless data transmission optimization method and system, and relates to the technical field of data transmission, and the method comprises the steps: generating a signal-to-noise ratio-frequency trajectory curve based on symmetrical offset positions at two sides of a carrier center frequency, taking a signal-to-noise ratio minimum frequency point of the signal-to-noise ratio-frequency trajectory curve as an abnormal center frequency, and calculating an abnormal broadband; calculating a left end point and a right end point of a prohibited area in the continuous domain based on the abnormal center frequency and the abnormal broadband, and performing resource block screening on PRB grids based on the left end point and the right end point to obtain a PRB allowable set; determining the optimal beam direction of the millimeter wave phased-array antenna based on the PRB allowable set; and according to the PRB allowable set and the optimal beam direction, performing evaluation and optimization on the allowable cyclic shift set of the DMRS signal to obtain the optimal cyclic shift. The method can dynamically adapt to the deformation change of the metal roof gap, and continuously guarantees the stable communication performance.

Description

Technical Field

[0001] This invention relates to the field of data transmission technology, and in particular to a method and system for optimizing efficient wireless data transmission. Background Technology

[0002] In wireless data transmission scenarios between high-speed trains and ground base stations, trains typically rely on a shark fin antenna mounted on the roof to protect the internal millimeter-wave phased array antenna and maintain a stable communication link. To meet requirements for sealing, thermal expansion and contraction, and maintenance, a gap is reserved around the circumferential edge of the shark fin antenna and the metal roof. This gap undergoes millimeter-level dynamic changes due to vehicle pitch, wind pressure fluctuations, and vibrations during high-speed train operation. Furthermore, high-speed train communication often utilizes a carrier center frequency in the 26GHz band to leverage the high bandwidth of millimeter waves to support high-speed data transmission.

[0003] When subjected to pantograph arcing interference, gaps in the metal roof of the train can generate a localized, narrow, anomalous frequency band near the carrier center frequency. The location and bandwidth of this anomalous frequency band change dynamically with the gap's deformation and the arc's spectral characteristics. This concealed and time-varying anomalous frequency band causes a sharp drop in the signal-to-noise ratio of the wireless signal, and increases the error vector amplitude and block error rate during signal transmission. This not only reduces data throughput and affects passenger experience, but can also lead to delays or errors in control command transmission, posing a potential threat to train operation safety.

[0004] To address the aforementioned issues in high-speed train communication, existing technologies mostly employ fixed frequency band allocation or static resource allocation strategies, which allocate physical resource blocks within a preset frequency range without considering dynamic abnormal frequency bands caused by gaps in the metal roof and arc interference. Some solutions enhance antenna transmission power to combat interference, but this can exacerbate interference in adjacent tracks, making it difficult to fundamentally avoid the impact of abnormal frequency bands. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies that rely on increasing antenna transmission power to combat interference, which makes it difficult to fundamentally avoid the influence of abnormal frequency bands. Therefore, this invention proposes an efficient wireless data transmission optimization method and system.

[0006] To address the problems existing in the prior art, the present invention adopts the following technical solution: An efficient wireless data transmission optimization method includes: S1. Generate a signal-to-noise ratio (SNR)-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency. Take the frequency point with the minimum SNR of the SNR-frequency trajectory curve as the abnormal center frequency and calculate the abnormal bandwidth. S2. Calculate the left and right endpoints of the forbidden zone in the continuous domain based on the abnormal center frequency and abnormal bandwidth, and perform resource block filtering on the PRB grid based on the left and right endpoints to obtain the PRB allowed set. S3. Determine the optimal beam direction of the millimeter-wave phased array antenna based on the PRB allowable set; S4. Based on the PRB allowable set and the optimal beam direction, evaluate and optimize the allowable cyclic shift set of the DMRS signal to obtain the optimal cyclic shift.

[0007] S5. Calculate the required number of PRBs based on the number of available resource elements in a single PRB, and distribute the required number of PRBs equally on both sides according to the left and right ends to obtain the PRB mapping table. S6. Generate a transmission optimization scheme for high-speed train wireless data based on the PRB allowable set, PRB mapping table, optimal beam direction, and optimal cyclic shift.

[0008] Preferably, the signal-to-noise ratio-frequency trajectory curve is generated based on the symmetrical offset positions on both sides of the carrier center frequency, including: Based on the carrier center frequency and the preset offset, calculate the frequencies corresponding to the left symmetrical offset position and the right offset position of the carrier center frequency, respectively. The signal-to-noise ratio (SNR) was measured at the left symmetrical offset position and the right offset position respectively, and the SNR of the left side and the SNR of the right side were obtained. Several measurement points are added at the left symmetrical offset position and the right offset position according to a fixed step size, and the signal-to-noise ratio of the measurement points is measured to obtain the signal-to-noise ratio of the measurement points. The frequency and signal-to-noise ratio of the measurement points are used as discrete data pairs. By fitting discrete data pairs, the signal-to-noise ratio-frequency trajectory curve is obtained.

[0009] Preferably, the frequency point with the lowest signal-to-noise ratio on the signal-to-noise ratio-frequency trajectory curve is taken as the abnormal center frequency, and the abnormal bandwidth is calculated, including: The minimum signal-to-noise ratio is obtained by searching for the extreme values ​​of the signal-to-noise ratio-frequency trajectory curve. The minimum signal-to-noise ratio (SNR) is located, and the frequency point with the minimum SNR is obtained. The frequency point with the minimum SNR is then used as the abnormal center frequency. Calculate the 3dB signal-to-noise ratio threshold based on the abnormal center frequency; On the signal-to-noise ratio-frequency trajectory curve, find the left and right frequency points corresponding to the 3dB signal-to-noise ratio threshold on the left and right sides of the abnormal center frequency, respectively. Subtract the left-side frequency point from the abnormal center frequency to obtain the left half-width; Subtract the abnormal center frequency from the right side frequency point to obtain the right half width; The smaller value between the left and right half-widths is taken as the abnormal bandwidth.

[0010] Preferably, the left and right endpoints of the forbidden zone within the continuous domain are calculated based on the abnormal center frequency and abnormal bandwidth. Resource blocks are then filtered through the PRB raster based on these left and right endpoints to obtain the PRB allowed set, which includes: The abnormal bandwidth is added to the preset protection bandwidth to obtain the unilateral extended bandwidth; Subtracting the one-sided extended bandwidth from the abnormal center frequency yields the left endpoint of the forbidden zone, and adding the one-sided extended bandwidth to the abnormal center frequency yields the right endpoint of the forbidden zone. The frequency range of the prohibited zone is determined based on the left and right endpoints; If the frequency range of one of the PRBs in the PRB grid overlaps with the frequency range of the forbidden area, the PRB is marked as a forbidden resource block; otherwise, the PRB is marked as a permitted resource block. All allowed resource blocks are aggregated into a PRB allowed set.

[0011] Preferably, determining the optimal beam direction of the millimeter-wave phased array antenna based on the PRB allowable set includes: Based on the PRB allowable set, a DMRS signal is transmitted for each candidate beam azimuth, and the received signal vector of the candidate beam azimuth is acquired. ; Based on the received signal vector Calculate the degree of deviation between the actual transmitted signal and the ideal signal; All deviation levels are compiled into a deviation level set, and the minimum deviation level in the deviation level set is selected. The candidate beam orientation corresponding to the minimum deviation is taken as the optimal beam direction of the millimeter-wave phased array antenna.

[0012] Preferably, the allowable cyclic shift set of the DMRS signal is evaluated and optimized based on the PRB allowable set and the optimal beam direction to obtain the optimal cyclic shift, including: Under the constraints of the PRB allowable set and the optimal beam direction, DMRS signals are sent for each cyclic shift in the allowable cyclic shift set, and the actual received signals of the cyclic shift are acquired. The DMRS signal is cyclically shifted to obtain the shifted ideal signal; Cross-correlation is performed on the actual received signal and the ideal signal after cyclic shifting to calculate the correlation degree; The maximum relevance is selected from all relevance values, and the cyclic shift corresponding to the maximum relevance is determined as the optimal cyclic shift.

[0013] Preferably, the required number of PRBs is calculated based on the number of available resource elements in a single PRB, and the required number of PRBs is evenly distributed between the left and right ends to obtain a PRB mapping table, including: Obtain the modulation order and coding rate of the wireless physical channel between the high-speed train and the base station; The maximum number of bits carried by a single PRB is obtained by multiplying the adjustment order, coding rate, and the number of available resource elements in a single PRB. Calculate the required number of PRBs based on the total required bits and the maximum carrying bits of the PRB; Under the constraint of the allowed set of PRBs, the number of demand PRBs is evenly distributed to the left side of the left endpoint and the right side of the right endpoint. Generate a PRB mapping table based on the left and right regions.

[0014] Preferably, the transmission optimization scheme includes: Resource blocks for wireless physical channels are allocated according to the PRB allowable set and the PRB mapping table; The optimal beam direction is taken as the working direction of the millimeter-wave phased array antenna. The cyclic shift configuration of the demodulation reference signal is determined based on the optimal cyclic shift.

[0015] To address the above problems, the present invention also provides a high-efficiency wireless data transmission optimization system, the system comprising: The abnormal bandwidth calculation module is used to generate a signal-to-noise ratio-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency, take the frequency point with the minimum signal-to-noise ratio of the signal-to-noise ratio-frequency trajectory curve as the abnormal center frequency, and calculate the abnormal bandwidth. PRB allowable sets are grouped into modules, which are used to calculate the left and right endpoints of the forbidden zone in the continuous domain based on the abnormal center frequency and abnormal bandwidth, and to filter resource blocks of the PRB grid based on the left and right endpoints to obtain the PRB allowable set; The optimal beam direction determination module is used to determine the optimal beam direction of the millimeter-wave phased array antenna based on the PRB allowable set. The optimal cyclic shift determination module is used to evaluate and optimize the set of permissible cyclic shifts of the DMRS signal based on the PRB permissible set and the optimal beam direction, so as to obtain the optimal cyclic shift.

[0016] The PRB mapping table determination module is used to calculate the required number of PRBs based on the number of available resource elements of a single PRB, and to distribute the required number of PRBs equally on both sides according to the left and right ends to obtain the PRB mapping table. The transmission optimization scheme generation module is used to generate a transmission optimization scheme for high-speed train wireless data based on the PRB allowable set, PRB mapping table, optimal beam direction, and optimal cyclic shift.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. In this invention, by generating a signal-to-noise ratio-frequency trajectory curve to locate the abnormal center frequency and bandwidth, calculating the endpoints of the forbidden zone and filtering the PRB allowable set, the interference frequency band can be accurately avoided, and the allocation of physical resource blocks is strictly limited to the spectrum range without abnormal interference. This effectively improves the signal-to-noise ratio of wireless signals, reduces the error vector amplitude and block bit error rate during signal transmission, ensures stable data throughput, avoids control command transmission delays or errors, and enhances train operation safety and passenger service experience.

[0018] 2. In this invention, the optimal beam direction of the millimeter-wave phased array antenna is determined based on the PRB allowable set. At the same time, the optimal beam direction is combined with the cyclic shift of the demodulation reference signal optimized by the set and the beam direction. The optimal beam direction can adapt to the dynamic channel characteristics of the train and focus on the effective communication area. The optimal cyclic shift reduces the interference between reference signals, improves the channel estimation accuracy, enhances the signal anti-interference capability, and further improves the reliability of the communication link. This solves the defects of the prior art that only relies on power enhancement or static beam configuration and cannot adapt to dynamic interference.

[0019] 3. In this invention, the required number of PRBs is calculated based on the available resource elements of a single PRB, and then evenly distributed to the two sides of the restricted zone according to the left and right endpoints, forming a PRB mapping table. This allocation method fully utilizes the available spectrum resources on both sides of the abnormal frequency band, achieving balanced scheduling and fine-grained configuration of resources, and improving spectrum utilization. Compared with the fixed frequency band division or static allocation strategy of the prior art, it can dynamically adapt to the deformation changes of the metal roof gaps, continuously ensuring stable communication performance and meeting the high-speed train's requirements for efficient and reliable wireless data transmission. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a flowchart illustrating an efficient wireless data transmission optimization method according to an embodiment of the present invention. Figure 2 This is a functional block diagram of an efficient wireless data transmission optimization system provided in an embodiment of the present invention. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] Example: This example provides a method for optimizing efficient wireless data transmission. See [link to example]. Figure 1 Specifically, including: S1. Generate a signal-to-noise ratio (SNR)-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency. Take the frequency point with the minimum SNR of the SNR-frequency trajectory curve as the abnormal center frequency and calculate the abnormal bandwidth. In an embodiment of the present invention, generating a signal-to-noise ratio-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency includes: Based on the carrier center frequency and the preset offset, calculate the frequencies corresponding to the left symmetrical offset position and the right offset position of the carrier center frequency, respectively. Specifically, the carrier center frequency used for high-speed train communication is first determined. Based on preliminary research into pantograph arc interference and the characteristics of the shark fin cover gap, an offset is pre-set. This offset setting comprehensively considers factors such as the wavelength characteristics of the 26GHz carrier, the millimeter-level dynamic variation range of the gap between the shark fin cover and the metal roof, and the frequency influence range of pantograph arc interference, ensuring coverage of potentially abnormal frequency bands. Using the carrier center frequency as the base value, a subtraction operation is performed: subtracting the pre-set offset from the carrier center frequency yields the frequency corresponding to the symmetrical offset position to the left of the carrier center frequency. Then, the pre-set offset is added to the carrier center frequency, yielding the frequency corresponding to the offset position to the right of the carrier center frequency. This precisely determines two key frequency points for subsequent signal-to-noise ratio measurements.

[0023] Specifically, the carrier center frequency refers to the reference frequency value of the high-frequency carrier signal used to carry information during wireless data transmission between high-speed trains and base stations. It is the central reference point of the entire communication frequency band, and its value determines the core frequency position of wireless signal transmission. The carrier center frequency belongs to the data of the wireless communication system composed of high-speed trains and base stations, and is the basic frequency parameter jointly followed by both parties when performing signal modulation, transmission, reception, and resource scheduling.

[0024] The signal-to-noise ratio (SNR) was measured at the left symmetrical offset position and the right offset position respectively, and the SNR of the left side and the SNR of the right side were obtained. Specifically, the signal receiving module configured in the millimeter-wave phased array antenna system on the roof of the high-speed train is used. This module has the function of detecting and analyzing signals at specific frequency positions. The operating frequency of the signal receiving module is adjusted to the frequency value corresponding to the left symmetrical offset position, so that it continuously receives the wireless communication signal at that frequency position for a certain period of time. This period of time needs to be set according to the stability requirements of signal transmission during train operation and the characteristics of pantograph arc interference to ensure that representative signal data can be collected. During the reception process, the signal receiving module separates and calculates the power and noise power of the received signal according to the built-in signal-to-noise ratio (SNR) calculation algorithm. The SNR at the left symmetrical offset position is obtained by dividing the signal power by the noise power, and is recorded as the left SNR. In the same way, the operating frequency of the signal receiving module is adjusted to the frequency value corresponding to the right offset position, and the above operation process of signal reception, power calculation and SNR calculation is repeated to obtain the SNR at the right offset position, which is recorded as the right SNR. In this way, key SNR data for subsequent abnormal frequency band analysis is obtained at the two offset positions.

[0025] Several measurement points are added at the left symmetrical offset position and the right offset position according to a fixed step size, and the signal-to-noise ratio of the measurement points is measured to obtain the signal-to-noise ratio of the measurement points. The frequency and signal-to-noise ratio of the measurement points are used as discrete data pairs. By fitting discrete data pairs, the signal-to-noise ratio-frequency trajectory curve is obtained.

[0026] Specifically, firstly, based on a preset fixed step size, starting from the symmetrical offset position on the left, the frequencies of several measurement points are gradually calculated and added in the direction of decreasing frequency; simultaneously, starting from the offset position on the right, the frequencies of several measurement points are gradually calculated and added in the direction of increasing frequency with the same fixed step size; then, using the same signal receiving module and algorithm as those used to measure the signal-to-noise ratio (SNR) on the left and right sides, the SNR of each added measurement point is measured to obtain the SNR corresponding to each measurement point; the frequency of each measurement point is mapped one-to-one with the SNR measured at that point to construct discrete data pairs; then, algorithms such as polynomial fitting are used to fit all discrete data pairs to generate a continuous SNR-frequency trajectory curve.

[0027] In detail, when the shark fin cover is installed on the train roof, a gap is reserved around the circumferential edge of the cover and the metal roof to meet the requirements of sealing, thermal expansion and contraction and maintenance. Due to the installation design, the gap in the metal roof presents a wedge shape that is slightly wider on one side and gradually narrows on the other side. Moreover, during train operation, the gap width will dynamically change at the millimeter level due to the pitch of the train body, wind pressure fluctuations and vibrations.

[0028] In general, when the gap in the metal roof is interfered with by the pantograph arc, it will excite a local narrow abnormal frequency band in the vicinity of the working carrier of the millimeter-wave phased array antenna. Since the frequency position and bandwidth of this abnormal frequency band are affected by the dynamic deformation of the gap and the spectral characteristics of the arc, it has the characteristics of concealment and time variation. Therefore, it is necessary to first generate the signal-to-noise ratio-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency. By measuring and fitting the signal-to-noise ratio of the frequency points symmetrically extended to the left and right of the carrier center frequency, the signal-to-noise ratio distribution characteristics of the frequency around the carrier can be continuously characterized.

[0029] In an embodiment of the present invention, the frequency point with the lowest signal-to-noise ratio (SNR) on the SNR-frequency trajectory curve is taken as the abnormal center frequency, and the abnormal bandwidth is calculated, including: The minimum signal-to-noise ratio is obtained by searching for the extreme values ​​of the signal-to-noise ratio-frequency trajectory curve. The minimum signal-to-noise ratio (SNR) is located, and the frequency point with the minimum SNR is obtained. The frequency point with the minimum SNR is then used as the abnormal center frequency. Specifically, for the generated signal-to-noise ratio (SNR)-frequency trajectory curve, the SNR values ​​corresponding to each frequency point are compared one by one by traversing the discrete data pairs contained in the curve, or by performing derivative operations on the fitted continuous function and finding the extreme points. The SNR result with the smallest value is selected and recorded as the minimum SNR. Then, based on the distribution position of the minimum SNR in the trajectory curve, its corresponding frequency coordinates are retrieved in reverse to determine the frequency point. Since the combined interference of the metal roof gap and the pantograph arc is most significant at this frequency point, causing the SNR to show the lowest state, this frequency point is determined as the abnormal center frequency.

[0030] The 3dB signal-to-noise ratio (SNR) threshold is calculated based on the abnormal center frequency. The formula for calculating the 3dB SNR threshold is as follows: In the formula, It is the signal-to-noise ratio threshold. It is the abnormal center frequency. yes Signal-to-noise ratio at the location It is a 3dB linear scaling factor; Specifically, in the field of communications, decibels are used to quantify relative changes in power, and are defined as the logarithm of the power ratio. When the power changes by 3 dB, it can be derived that the corresponding linear power ratio is... The signal-to-noise ratio (SNR) is approximately 2, meaning a 3dB increase in power implies that the signal power is approximately twice the original power. The SNR at the abnormal center frequency is the minimum value in the trajectory curve, representing the most severe interference at that frequency. As the interference extends towards both sides of this frequency, the interference weakens, and the SNR gradually increases. (Calculation) At that time, the signal-to-noise ratio at the abnormal center frequency is used as a basis, multiplied by A threshold 3dB higher than the signal-to-noise ratio (SNR) at the anomaly center is obtained. This threshold is used to locate the frequency points on the SNR-frequency trajectory curve where the SNR increases by 3dB compared to the anomaly center. The interval between these two points is the bandwidth of the anomaly frequency band. The 3dB criterion is a classic method for defining the effective bandwidth of a signal; here, it is applied in reverse to characterize the range of the interference frequency band.

[0031] On the signal-to-noise ratio-frequency trajectory curve, find the left and right frequency points corresponding to the 3dB signal-to-noise ratio threshold on the left and right sides of the abnormal center frequency, respectively. Subtract the left-side frequency point from the abnormal center frequency to obtain the left half-width; Subtract the abnormal center frequency from the right side frequency point to obtain the right half width; The smaller value between the left and right half-widths is taken as the abnormal bandwidth.

[0032] Specifically, on the signal-to-noise ratio (SNR)-frequency trajectory curve, using the abnormal center frequency as a reference, the frequency and corresponding SNR data are traversed point by point along the trajectory curve, moving to the left where the frequency decreases and to the right where the frequency increases. When the SNR of a certain frequency point is equal to the pre-calculated 3dB SNR threshold, that frequency point is recorded. The frequency point obtained from the left-side traversal is called the left-side frequency point, and the frequency point obtained from the right-side traversal is called the right-side frequency point. The left half-width is obtained by subtracting the value of the left-side frequency point from the abnormal center frequency; the right half-width is obtained by subtracting the abnormal center frequency from the value of the right-side frequency point. The values ​​of the left and right half-widths are compared, and the smaller value is selected as the abnormal bandwidth.

[0033] Specifically, the abnormal bandwidth refers to the frequency range where the signal-to-noise ratio (SNR) of the wireless communication signal does not increase by more than 3 dB compared to the minimum value at the abnormal center frequency under the combined influence of the metal roof gap and the pantograph arc. This range is defined by finding the corresponding 3 dB SNR threshold frequency points on both sides of the abnormal center frequency on the SNR-frequency trajectory curve. Due to the asymmetric characteristics of the gap's dynamic deformation and arc interference, the left and right half-widths may differ; therefore, the smaller of the two values ​​is selected as the abnormal bandwidth to accurately characterize the frequency range affected by the interference.

[0034] S2. Calculate the left and right endpoints of the forbidden zone in the continuous domain based on the abnormal center frequency and abnormal bandwidth, and perform resource block filtering on the PRB grid based on the left and right endpoints to obtain the PRB allowed set. In an embodiment of the present invention, the left and right endpoints of the forbidden zone within a continuous domain are calculated based on the abnormal center frequency and abnormal bandwidth. Resource blocks are then filtered on the PRB grid based on the left and right endpoints to obtain the PRB allowed set, including: The abnormal bandwidth is added to the preset protection bandwidth to obtain the unilateral extended bandwidth; Specifically, the preset protection bandwidth is a fixed frequency interval pre-configured during the wireless communication system design phase, based on the pantograph arc spurious radiation characteristics, the dynamic interference spread range of the metal roof gap, and the tolerance requirements of the communication standard for adjacent channel interference. This bandwidth is used to establish an isolation buffer zone between the prohibited area and the surrounding normal frequency range in the continuous domain, to prevent interference signals in the prohibited area from eroding adjacent frequency bands through frequency leakage, and to ensure the stable communication performance of the permitted resource block.

[0035] Subtracting the one-sided extended bandwidth from the abnormal center frequency yields the left endpoint of the forbidden zone, and adding the one-sided extended bandwidth to the abnormal center frequency yields the right endpoint of the forbidden zone. The frequency range of the prohibited zone is determined based on the left and right endpoints; Specifically, considering the spurious interference characteristics at the edge of the abnormal frequency band, the abnormal bandwidth is superimposed with the preset protection bandwidth to obtain the single-sided extended bandwidth. The protection bandwidth is used to isolate the interference frequency band from the adjacent normal frequency band to prevent the interference from spreading to adjacent resource blocks. Based on the abnormal center frequency, the left endpoint of the forbidden zone is obtained by subtraction and the right endpoint of the forbidden zone is obtained by addition, thereby clarifying the continuous frequency range of the forbidden zone.

[0036] If the frequency range of one of the PRBs in the PRB grid overlaps with the frequency range of the forbidden area, the PRB is marked as a forbidden resource block; otherwise, the PRB is marked as a permitted resource block. Specifically, the process iterates through all PRBs contained in the PRB grid, extracting the start and end values ​​of each PRB to define its frequency coverage range. Using the left and right endpoints of the forbidden zone as the boundaries of the interference band, if the start value of the current PRB is less than the right endpoint of the forbidden zone and the end value is greater than the left endpoint, meaning their frequency ranges overlap, then the PRB is determined to have an overlapping frequency range with the forbidden zone and is marked as a forbidden resource block. If the start value of the current PRB is greater than or equal to the right endpoint of the forbidden zone, or the end value is less than or equal to the left endpoint, meaning their frequency ranges do not overlap, then the PRB is marked as an allowed resource block.

[0037] Specifically, the prohibited zone within the continuous domain is a frequency range within the communication band that is subject to interference, defined by the abnormal center frequency, abnormal bandwidth, and preset protection bandwidth. It is used to identify the frequency range affected by metal roof gaps and pantograph arc interference. The PRB grid is a standardized, gridded architecture for dividing wireless frequency resources in a communication system, clearly defining the frequency spacing and distribution rules of physical resource blocks. A PRB, or Physical Resource Block, is the basic unit for allocating wireless communication frequency resources, corresponding to a specific frequency sub-interval. A prohibited resource block is a PRB within the PRB grid whose frequency range overlaps with the prohibited zone frequency range within the continuous domain; it cannot carry data transmission due to interference. An allowed resource block is a PRB within the PRB grid whose frequency range does not overlap with the prohibited zone frequency range within the continuous domain, and it can stably support wireless data transmission.

[0038] All allowed resource blocks are aggregated into a PRB allowed set.

[0039] S3. Determine the optimal beam direction of the millimeter-wave phased array antenna based on the PRB allowable set; In embodiments of the present invention, determining the optimal beam direction of a millimeter-wave phased array antenna based on the PRB allowable set includes: Based on the PRB allowable set, a DMRS signal is transmitted for each candidate beam azimuth, and the received signal vector of the candidate beam azimuth is acquired. ; Specifically, the PRB allowable set contains all PRB individuals marked as allowable resource blocks, and each PRB has a predefined frequency start value and frequency end value. Then, each candidate beam azimuth in the candidate beam azimuth set is traversed. For the current candidate beam azimuth, the frequency boundary parameters (frequency start value and frequency end value) of all PRBs in the PRB allowable set are extracted to sort out the frequency resource range that can be used for signal transmission under that beam azimuth. The millimeter-wave phased array antenna is controlled to switch to the candidate beam azimuth. Within the sorted frequency resource range, the DMRS signal is transmitted in accordance with the DMRS signal format, transmit power and time domain scheduling rules specified by the communication standard. At the receiving end, the receiving link adapted to the beam azimuth is activated, and synchronous acquisition, down-conversion, analog-to-digital sampling and baseband synchronous calibration are performed on the spatially propagated signal. The calibrated received signal is integrated according to the sampling sequence dimension within the symbol period to generate the received signal vector of the corresponding candidate beam azimuth, ensuring that the transmission frequency band of the DMRS signal strictly matches the resource range of the PRB allowable set.

[0040] Specifically, candidate beam orientation refers to a set of multiple spatial radiation pointing angles pre-planned by the millimeter-wave phased array antenna at the train end in the high-speed train vehicle-to-ground communication system. These angles are used to cover the possible communication directions during train operation, with each orientation corresponding to an independent spatial beam radiation pointing direction. The DMRS signal, or demodulation reference signal, is a known reference signal generated in accordance with wireless communication standards. It belongs to the signal resources for bidirectional interaction between the train and the base station in the vehicle-to-ground communication system and is used by the receiver to perform channel estimation and signal demodulation during candidate beam orientation testing.

[0041] Based on the received signal vector The deviation between the actual transmitted signal and the ideal signal is calculated using the following formula: In the formula It is the first The degree of deviation in the azimuth of each candidate beam. It is the first The received signal vector of each candidate beam orientation It is the first Average channel coefficients for each candidate beam azimuth It is an ideal signal vector; Specifically, the formula for calculating the error vector magnitude characterizes transmission distortion by quantifying the deviation between the actual received signal and the theoretical signal after channel mapping of the ideal signal: in the numerator... middle, Analog ideal signal via the first The sum of the squares of the difference between the theoretical received value after channel transmission for each candidate beam azimuth and the actual received signal vector is calculated, and the sum of the squares of the moduli is accumulated to sum the amplitude and phase deviation energy of all sampling points; the denominator term is... The energy of the ideal signal is normalized to eliminate the interference of signal power differences on the deviation measurement; the square root operation converts the deviation energy into the root mean square form, so that the result directly reflects the comprehensive deviation of the actual transmitted signal (after propagation through the channel) from the ideal signal in the amplitude and phase dimensions, so as to conform to the quantification logic of signal distortion in wireless communication.

[0042] Specifically, the average channel coefficient for the candidate beam azimuth is for the first... The channel characteristics quantization value is obtained by statistically averaging the channel response data collected multiple times under the candidate beam azimuth using a channel estimation algorithm. This quantization value is used to characterize the combined laws of attenuation, phase shift, and multipath effects of the signal when it is transmitted in the wireless channel under that beam azimuth. The ideal signal vector is a reference signal waveform pre-constructed according to the communication standard. Its amplitude, phase sequence, and time / frequency domain structure are strictly defined, serving as a benchmark template for measuring the degree of distortion of the actual signal. The received signal vector of the candidate beam azimuth is obtained by... Under each candidate beam orientation, the receiver sequentially performs down-conversion, analog-to-digital conversion, and synchronization calibration on the signal propagating in the air. The signal set is then integrated according to a preset sampling dimension to accurately record the amplitude, phase, and time-domain evolution characteristics of the actual received signal under that beam orientation.

[0043] All deviation levels are compiled into a deviation level set, and the minimum deviation level in the deviation level set is selected. The candidate beam orientation corresponding to the minimum deviation is taken as the optimal beam direction of the millimeter-wave phased array antenna.

[0044] Specifically, due to differences in spatial pointing, the attenuation characteristics and multipath distribution patterns of the corresponding wireless channels vary among candidate beam orientations, resulting in differences in the degree of deviation between the actual received signal and the ideal signal in each orientation. By compiling the deviation degrees of all candidate beam orientations into a set, a complete characterization of beam performance in the spatial dimension can be achieved. Since the minimum deviation degree directly quantifies the fidelity level of the signal after transmission through the channel, the smaller the value, the more subtle the deviation of the actual transmitted signal from the ideal signal in the amplitude and phase dimensions, indicating better channel adaptability and lower transmission distortion for the corresponding beam orientation. Determining the candidate beam orientation corresponding to the minimum deviation degree as the optimal beam direction for the millimeter-wave phased array antenna enables the antenna to minimize signal distortion when transmitting signals in that direction, improving the accuracy and reliability of data transmission and meeting the optimization requirements of wireless communication systems for signal quality and transmission performance.

[0045] Specifically, millimeter-wave phased array antennas are radio frequency front-end devices integrated into high-speed trains. As the core transceiver hardware of the vehicle-to-ground communication system, they can quickly switch the azimuth of candidate beams and perform beamforming by adjusting the phase and amplitude of the array units, thus adapting to the dynamic communication link requirements of high-speed trains.

[0046] S4. Based on the PRB allowable set and the optimal beam direction, evaluate and optimize the allowable cyclic shift set of the DMRS signal to obtain the optimal cyclic shift.

[0047] In an embodiment of the present invention, the allowable cyclic shift set of the DMRS signal is evaluated and optimized based on the PRB allowable set and the optimal beam direction to obtain the optimal cyclic shift, including: Under the constraints of the PRB allowable set and the optimal beam direction, DMRS signals are sent for each cyclic shift in the allowable cyclic shift set, and the actual received signals of the cyclic shift are acquired. Specifically, the process involves analyzing the time-frequency resource range and time-domain scheduling position corresponding to each PRB in the PRB allowable set; extracting the selected optimal beam direction; and locking the spatial radiation direction of the millimeter-wave phased array antenna. Then, iterates through each cyclic shift in the allowable cyclic shift set. For the current cyclic shift: at the transmitter, based on the time-frequency resources of the PRB allowable set, baseband cyclic shift processing is performed on the standard DMRS signal to generate a transmit signal matching the cyclic shift; the millimeter-wave phased array antenna is controlled along the optimal beam direction to modulate the transmit signal to the carrier frequency corresponding to the PRB allowable set, and transmitted according to a preset timing sequence; at the receiver, the receiving link adapted to the optimal beam direction is synchronously activated, and the air signal is captured according to the time-frequency position of the PRB allowable set. After down-conversion, analog-to-digital conversion, and synchronization calibration, the baseband signal sequence corresponding to the current cyclic shift is extracted as the actual received signal for that cyclic shift.

[0048] Specifically, the allowed cyclic shift set is a set of predefined or dynamically configured cyclic shift parameters used to perform cyclic shift operations on the reference signal sequence to meet multi-user multiplexing, orthogonality requirements, or channel adaptability requirements. The specific value range and combination method are determined by the communication protocol or system configuration parameters. Each cyclic shift in the allowed cyclic shift set is a specific shift parameter contained in the set, used to specify the number of sampling points to be moved and the time-domain direction when performing cyclic shift on the demodulated reference signal. Its value is pre-set by the communication system according to channel characteristics, multi-user multiplexing requirements, and protocol specifications, and belongs to system configuration data.

[0049] The DMRS signal is cyclically shifted to obtain the shifted ideal signal; Specifically, firstly, the system extracts the predefined DMRS signal, which has a fixed amplitude sampling distribution and time-domain phase characteristics. For the current cyclic shift parameter within the allowed cyclic shift set, following the cyclic shift operation logic, the time-domain sampling points of the original sequence are cyclically shifted from the end sampling point to the beginning point according to the shift direction and shift step size, keeping the sequence length consistent with the original DMRS signal. Through this operation, an ideal shifted signal that strictly corresponds to the current cyclic shift parameter is generated, and its waveform exhibits cyclic offset characteristics in the time domain dimension.

[0050] Cross-correlation is performed on the actual received signal and the ideal signal after cyclic shifting to calculate the correlation degree; Specifically, the actual received signal after cyclic shift and the ideal signal after shift are synchronized and aligned on the time axis, and the corresponding discrete signal values ​​are extracted point by point. For each corresponding sample point, the complex conjugate of the actual received signal value and the ideal signal value are multiplied point by point to obtain a product sequence. All elements of the product sequence are summed to obtain the cross-correlation result. The power summation of the actual received signal and the ideal signal is calculated separately, that is, the summation of the squares of the discrete values ​​of each signal. The cross-correlation result is divided by the square root of the product of the power of the actual received signal and the power of the ideal signal to obtain the normalized correlation.

[0051] The maximum relevance is selected from all relevance values, and the cyclic shift corresponding to the maximum relevance is determined as the optimal cyclic shift.

[0052] Specifically, correlation is an index that quantifies the degree of matching between the actual received signal and the ideal signal after cyclic shift in terms of time-domain waveform and phase distribution. The larger the value, the smaller the difference between the two due to factors such as channel transmission and synchronization deviation, and the fewer sources of error during signal demodulation. Selecting the maximum correlation from all correlation values ​​is essentially choosing the signal offset mode that best suits the current channel characteristics (such as time delay and multipath superposition). Determining the cyclic shift corresponding to the maximum correlation value as the optimal cyclic shift allows the receiver to maximize the use of the signal consistency characteristics during demodulation, reduce the impact of noise and interference on signal recovery, thereby improving the accuracy and stability of DMRS signal-assisted data demodulation and meeting the reliability requirements of high-speed train vehicle-to-ground communication for signal transmission.

[0053] S5. Calculate the required number of PRBs based on the number of available resource elements in a single PRB, and distribute the required number of PRBs equally on both sides according to the left and right ends to obtain the PRB mapping table. In an embodiment of the present invention, the required number of PRBs is calculated based on the number of available resource elements in a single PRB, and the required number of PRBs is evenly distributed between the left and right ends to obtain a PRB mapping table, including: Obtain the modulation order and coding rate of the wireless physical channel between the high-speed train and the base station; The maximum number of bits carried by a single PRB is obtained by multiplying the adjustment order, coding rate, and the number of available resource elements in a single PRB. Specifically, the modulation order determines the number of bits that a single resource element can carry, the coding rate reflects the proportion of effective data in the coded sequence, and the number of available resource elements in a single PRB defines the resource scale of data transmission. When these three are multiplied, the theoretical total number of uncoded bits in the PRB is first calculated from the modulation order and the number of available resource elements, and then the effectively transmitted bits are extracted from them through the coding rate, thereby accurately quantifying the maximum number of effective bits that a single PRB can stably carry in the channel after modulation and coding.

[0054] Specifically, the number of available resource elements in a single PRB refers to the number of resource elements that can be used for data transmission within the time-frequency range of a physical resource block. Its value is determined by physical layer parameters such as subcarrier spacing, cyclic prefix length, and time slot structure. The modulation order refers to the number of bits that each resource element can carry during modulation, and its value is determined by the modulation scheme. The coding rate is the ratio of the number of effective information bits to the total number of transmitted bits, used to measure the redundancy introduced by channel coding.

[0055] Calculate the required number of PRBs based on the total required bits and the maximum carrying bits of the PRB; Specifically, divide the total required bits by the maximum carrying bits. If the result is an integer, that integer is the required PRB quantity. If the result contains a remainder, round the quotient up to ensure that the total required bits can be fully carried, thus obtaining the required PRB quantity.

[0056] Under the constraint of the allowed set of PRBs, the number of demand PRBs is evenly distributed to the left side of the left endpoint and the right side of the right endpoint in the prohibited area; Specifically, this involves selecting the required number of PRBs from the available PRBs included in the PRB allowable set, dividing this number by 2 to obtain the base allocation number. If the base allocation number is an integer, the left and right regions are initially allocated that integer number of PRBs each. If the base allocation number has a remainder, the left region is allocated the base allocation number plus 1 of PRBs, and the right region is allocated the base allocation number of PRBs. Simultaneously, it is checked whether the allocation numbers on both sides do not exceed the total number of available PRBs in their respective regions. If there is an excess, the excess portion is adjusted from that region to another region to ensure that the sum of the PRBs allocated in the left and right regions equals the required number of PRBs, and both are within the available range of their respective regions, thus completing the allocation operation under the constraints of the PRB allowable set.

[0057] Generate a PRB mapping table based on the left and right regions.

[0058] Specifically, firstly, all allocated PRB numbers are extracted from the left region, and frequency domain parameters such as start frequency, end frequency, and subcarrier spacing, as well as time domain parameters such as slot number, symbol position, and duration, are recorded for each PRB. Simultaneously, all allocated PRB numbers are extracted from the right region, and their frequency and time domain parameters are recorded in the same manner. Then, the PRBs in the left region are sorted in ascending order of their numbers, and the PRBs in the right region are also sorted in ascending order of their numbers. Next, a table framework is constructed containing a region identifier column, a PRB number column, a frequency domain parameter column, and a time domain parameter column, where the region identifier column distinguishes the left and right regions. The sorted PRBs and their parameters from the left region are then filled into the corresponding columns of the table, and the sorted PRBs and their parameters from the right region are then filled into the corresponding columns of the table. Finally, the table content is validated to ensure that all PRBs belong to their corresponding regions and that their parameters are accurate, forming a complete PRB mapping table.

[0059] S6. Generate a transmission optimization scheme for high-speed train wireless data based on the PRB allowable set, PRB mapping table, optimal beam direction, and optimal cyclic shift.

[0060] In embodiments of the present invention, the transmission optimization scheme includes: Resource blocks for wireless physical channels are allocated according to the PRB allowable set and the PRB mapping table; The optimal beam direction is taken as the working direction of the millimeter-wave phased array antenna. The cyclic shift configuration of the demodulation reference signal is determined based on the optimal cyclic shift.

[0061] Specifically, the process begins by parsing the PRB allowable set to determine the time-frequency boundaries and time-domain scheduling rules of available PRBs. The PRB mapping table is then retrieved to obtain parameters such as the PRB number, frequency range, and time slot location. The resource block requirements of the wireless physical channels (such as the downlink shared channel PDSCH and the uplink shared channel PUSCH) are matched with the available PRBs in the PRB mapping table, and corresponding PRBs are allocated according to service type priority, ensuring that the time-frequency occupancy of resource blocks strictly conforms to the constraints of the PRB allowable set. Next, the angle parameters of the optimal beam direction, such as azimuth and elevation, are extracted. Through the element phase control module of the millimeter-wave phased array antenna, a corresponding phase offset is applied to each antenna element, causing the main beam radiated by the antenna to point in the optimal beam direction, achieving directional signal coverage for the high-speed train. Based on the optimal cyclic shift value, a cyclic shift operation is performed on the DMRS base sequence in the demodulation reference signal generation logic, setting the DMRS offset position in the time domain. This ensures that the receiver can complete channel estimation and data demodulation through this cyclic shift feature, collaboratively constructing an optimized configuration for the transmission of high-speed train wireless data.

[0062] like Figure 2The diagram shown is a functional block diagram of an efficient wireless data transmission optimization system provided in an embodiment of the present invention.

[0063] In this embodiment, the functions of each module / unit are as follows: The abnormal bandwidth calculation module is used to generate a signal-to-noise ratio-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency, take the frequency point with the minimum signal-to-noise ratio of the signal-to-noise ratio-frequency trajectory curve as the abnormal center frequency, and calculate the abnormal bandwidth. PRB allowable sets are grouped into modules, which are used to calculate the left and right endpoints of the forbidden zone in the continuous domain based on the abnormal center frequency and abnormal bandwidth, and to filter resource blocks of the PRB grid based on the left and right endpoints to obtain the PRB allowable set; The optimal beam direction determination module is used to determine the optimal beam direction of the millimeter-wave phased array antenna based on the PRB allowable set. The optimal cyclic shift determination module is used to evaluate and optimize the set of permissible cyclic shifts of the DMRS signal based on the PRB permissible set and the optimal beam direction, so as to obtain the optimal cyclic shift.

[0064] The PRB mapping table determination module is used to calculate the required number of PRBs based on the number of available resource elements of a single PRB, and to distribute the required number of PRBs equally on both sides according to the left and right ends to obtain the PRB mapping table. The transmission optimization scheme generation module is used to generate a transmission optimization scheme for high-speed train wireless data based on the PRB allowable set, PRB mapping table, optimal beam direction, and optimal cyclic shift.

[0065] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for optimizing efficient wireless data transmission, characterized in that, Includes the following steps: S1. Generate a signal-to-noise ratio (SNR)-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency. Take the frequency point with the minimum SNR of the SNR-frequency trajectory curve as the abnormal center frequency and calculate the abnormal bandwidth. S2. Calculate the left and right endpoints of the forbidden zone in the continuous domain based on the abnormal center frequency and abnormal bandwidth, and perform resource block filtering on the PRB grid based on the left and right endpoints to obtain the PRB allowed set. S3. Determine the optimal beam direction of the millimeter-wave phased array antenna based on the PRB allowable set; S4. Based on the PRB allowable set and the optimal beam direction, evaluate and optimize the allowable cyclic shift set of the DMRS signal to obtain the optimal cyclic shift. S5. Calculate the required number of PRBs based on the number of available resource elements in a single PRB, and distribute the required number of PRBs equally on both sides according to the left and right ends to obtain the PRB mapping table. S6. Generate a transmission optimization scheme for high-speed train wireless data based on the PRB allowable set, PRB mapping table, optimal beam direction, and optimal cyclic shift.

2. The efficient wireless data transmission optimization method according to claim 1, characterized in that, The signal-to-noise ratio-frequency trajectory curve is generated based on the symmetrical offset positions on both sides of the carrier center frequency, including: Based on the carrier center frequency and the preset offset, calculate the frequencies corresponding to the left symmetrical offset position and the right offset position of the carrier center frequency, respectively. The signal-to-noise ratio (SNR) was measured at the left symmetrical offset position and the right offset position respectively, and the SNR of the left side and the SNR of the right side were obtained. Several measurement points are added at the left symmetrical offset position and the right offset position according to a fixed step size, and the signal-to-noise ratio of the measurement points is measured to obtain the signal-to-noise ratio of the measurement points. The frequency and signal-to-noise ratio of the measurement points are used as discrete data pairs. By fitting discrete data pairs, the signal-to-noise ratio-frequency trajectory curve is obtained.

3. The efficient wireless data transmission optimization method according to claim 1, characterized in that, The frequency point with the lowest signal-to-noise ratio on the signal-to-noise ratio-frequency trajectory curve is taken as the center frequency of the anomaly, and the anomaly bandwidth is calculated, including: The minimum signal-to-noise ratio is obtained by searching for the extreme values ​​of the signal-to-noise ratio-frequency trajectory curve. The minimum signal-to-noise ratio (SNR) is located, and the frequency point with the minimum SNR is obtained. The frequency point with the minimum SNR is then used as the abnormal center frequency. Calculate the 3dB signal-to-noise ratio threshold based on the abnormal center frequency; On the signal-to-noise ratio-frequency trajectory curve, find the left and right frequency points corresponding to the 3dB signal-to-noise ratio threshold on the left and right sides of the abnormal center frequency, respectively. Subtract the left-side frequency point from the abnormal center frequency to obtain the left half-width; Subtract the abnormal center frequency from the right side frequency point to obtain the right half width; The smaller value between the left and right half-widths is taken as the abnormal bandwidth.

4. The efficient wireless data transmission optimization method according to claim 1, characterized in that, The left and right endpoints of the forbidden zone within the continuous domain are calculated based on the abnormal center frequency and abnormal bandwidth. Resource blocks are then filtered on the PRB raster based on the left and right endpoints to obtain the allowed set of PRBs, including: The abnormal bandwidth is added to the preset protection bandwidth to obtain the unilateral extended bandwidth; Subtracting the one-sided extended bandwidth from the abnormal center frequency yields the left endpoint of the forbidden zone, and adding the one-sided extended bandwidth to the abnormal center frequency yields the right endpoint of the forbidden zone. The frequency range of the prohibited zone is determined based on the left and right endpoints; If the frequency range of one of the PRBs in the PRB grid overlaps with the frequency range of the forbidden area, the PRB is marked as a forbidden resource block; otherwise, the PRB is marked as a permitted resource block. All allowed resource blocks are aggregated into a PRB allowed set.

5. The efficient wireless data transmission optimization method according to claim 1, characterized in that, Based on the PRB (Purpose-Based Rectification) set, the optimal beam direction of a millimeter-wave phased array antenna can be determined, including: Based on the PRB allowable set, a DMRS signal is transmitted for each candidate beam azimuth, and the received signal vector of the candidate beam azimuth is acquired. ; Based on the received signal vector Calculate the degree of deviation between the actual transmitted signal and the ideal signal; All deviation levels are compiled into a deviation level set, and the minimum deviation level in the deviation level set is selected. The candidate beam orientation corresponding to the minimum deviation is taken as the optimal beam direction of the millimeter-wave phased array antenna.

6. The efficient wireless data transmission optimization method according to claim 1, characterized in that, Based on the PRB allowable set and the optimal beam direction, the allowable cyclic shift set of the DMRS signal is evaluated and optimized to obtain the optimal cyclic shift, including: Under the constraints of the PRB allowable set and the optimal beam direction, DMRS signals are sent for each cyclic shift in the allowable cyclic shift set, and the actual received signals of the cyclic shift are acquired. The DMRS signal is cyclically shifted to obtain the shifted ideal signal; Cross-correlation is performed on the actual received signal and the ideal signal after cyclic shifting to calculate the correlation degree; The maximum relevance is selected from all relevance values, and the cyclic shift corresponding to the maximum relevance is determined as the optimal cyclic shift.

7. The efficient wireless data transmission optimization method according to claim 1, characterized in that, The required number of PRBs is calculated based on the number of available resource elements in a single PRB. The required number of PRBs is then evenly distributed between the left and right sides to obtain a PRB mapping table, including: Obtain the modulation order and coding rate of the wireless physical channel between the high-speed train and the base station; The maximum number of bits carried by a single PRB is obtained by multiplying the adjustment order, coding rate, and the number of available resource elements in a single PRB. Calculate the required number of PRBs based on the total required bits and the maximum carrying bits of the PRB; Under the constraint of the allowed set of PRBs, the number of demand PRBs is evenly distributed to the left side of the left endpoint and the right side of the right endpoint. Generate a PRB mapping table based on the left and right regions.

8. The efficient wireless data transmission optimization method according to claim 7, characterized in that, Transmission optimization schemes include: Resource blocks for wireless physical channels are allocated according to the PRB allowable set and the PRB mapping table; The optimal beam direction is taken as the working direction of the millimeter-wave phased array antenna. The cyclic shift configuration of the demodulation reference signal is determined based on the optimal cyclic shift.

9. A high-efficiency wireless data transmission optimization system, characterized in that, The system includes: The abnormal bandwidth calculation module is used to generate a signal-to-noise ratio-frequency trajectory curve based on the symmetrical offset positions on both sides of the carrier center frequency, take the frequency point with the minimum signal-to-noise ratio of the signal-to-noise ratio-frequency trajectory curve as the abnormal center frequency, and calculate the abnormal bandwidth. PRB allowable sets are grouped into modules, which are used to calculate the left and right endpoints of the forbidden zone in the continuous domain based on the abnormal center frequency and abnormal bandwidth, and to filter resource blocks of the PRB grid based on the left and right endpoints to obtain the PRB allowable set; The optimal beam direction determination module is used to determine the optimal beam direction of the millimeter-wave phased array antenna based on the PRB allowable set. The optimal cyclic shift determination module is used to evaluate and optimize the set of permissible cyclic shifts of the DMRS signal based on the PRB permissible set and the optimal beam direction, so as to obtain the optimal cyclic shift. The PRB mapping table determination module is used to calculate the required number of PRBs based on the number of available resource elements of a single PRB, and to distribute the required number of PRBs equally on both sides according to the left and right ends to obtain the PRB mapping table. The transmission optimization scheme generation module is used to generate a transmission optimization scheme for high-speed train wireless data based on the PRB allowable set, PRB mapping table, optimal beam direction, and optimal cyclic shift.

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