74 results about "Delay spread" patented technology

The invention provides an Internet of Vehicles broadcast frame radio frequency fingerprint identification method based on LMMSE channel estimation. The method comprises the following steps: obtaining subcarrier data in a resource grid based on an obtained signal of a physical side link broadcast channel; performing root-mean-square delay expansion and channel autocorrelation matrix construction based on the subcarrier data, and combining priori signal-to-noise ratio regularization and time domain windowing operation to obtain a channel estimation value; initial radio frequency fingerprint features are obtained through the channel equalization and the channel estimation value, and the improved neural network and the initial radio frequency fingerprint features are utilized to carry out classification identification on the Internet of Vehicles equipment. Influences of noise and channels on fingerprints are effectively considered, and the purpose of extracting fingerprints of different devices in a complex environment more accurately is achieved.

The invention relates to a coal mine underground accurate positioning card reader direction identification method, and belongs to the technical field of wireless communication and accurate positioning. In order to solve the problems of low direction identification precision and direction jump caused by dense metal supports, complex electromagnetic environment and serious multipath reflection in a coal mine in the prior art, a multi-source information fusion solution is provided. The method comprises the following steps: initiating a time of flight (TOF) ranging request through an identification card; based on the TOF distance difference interval gradient distribution weight point number, RSSI intensity difference interval differential weighting and CIR characteristic value peak-to-average ratio delay spread multipath component number, analyzing signal quality weighting, and combining historical direction information to dynamically compensate the weight point number; and finally determining the direction of the identification card by comparing the total weight points of the left and right antennas. According to the method, the direction identification accuracy in a complex mine environment is remarkably improved, the multi-path interference and signal fluctuation influence are effectively inhibited, the system anti-attenuation capability is enhanced, and the continuous stability of moving target direction tracking is guaranteed.

An apparatus configured to: receive a downlink signal; determine whether a TA stored at the apparatus is valid based, at least partially, on a reception timing of the received downlink signal and a delay spread value; and initiate small data transmission with a pre-configured uplink resource based, at least partially, on the determination that the TA is valid. An apparatus configured to: transmit, to a UE, a configuration comprising information related to TA validation for the UE, wherein the information comprises at least one of: an indication of a value configured to indicate a fraction of a cyclic prefix length of a symbol for reception of an uplink transmission from the UE, or a delay spread value; transmit a downlink signal; and receive a SDT based, at least partially, on the fraction of the length of the cyclic prefix, the transmitted downlink signal, and the delay spread value.

A system can utilize a first common physical uplink control channel (PUCCH) format 1 communication format for broadband cellular communications with user equipment via a channel. The system can estimate a first channel characteristic based on performing channel estimation on the channel over uplink signals, which comprises a Doppler spread. The system can estimate a second channel characteristic based on the performing of the channel estimation over uplink signals, which comprises a delay spread. The system can determine a number of symbols for a second common PUCCH format 1 communication format with the user equipment based on the first channel characteristic. The system can determine a group of initial cyclic shift indices for the second common PUCCH format 1 communication format with the user equipment based on the second channel characteristic. The system can communicate with the user equipment according to the second common PUCCH format 1 communication format.

The invention relates to the technical field of 5G communication security, and discloses a 5G short message encrypted transmission method, which comprises the following steps: acquiring time delay spread, angle spread and Doppler spread parameters of indoor multipath propagation, and generating a multi-dimensional channel characteristic matrix; acquiring a historical channel fingerprint database and a current channel feature matrix, and outputting a channel anomaly score; generating a three-dimensional decision space coordinate by using a threat-performance joint state space mapping algorithm; monitoring the real-time encryption queue length and the processing delay of each slice, calculating the actual SLA fulfillment rate and the security event interception rate, and generating a performance feedback vector; and inputting the performance feedback vector into a reward function calculation module of the reinforcement learning model, updating model parameters, and outputting an optimized decision strategy. According to the method, the interference of environmental noise on threat detection is avoided, the accuracy of pseudo base station attack identification is improved, and the problem of resource conflict arbitration in a multi-network slice scene is solved.

The embodiment of the invention discloses a method and device for determining a service sending and receiving point, which can be applied to the technical field of communication, and the method executed by terminal equipment comprises the following steps: measuring reference signals in a reference signal group sent by network equipment, and determining a measurement result, the measurement result comprises arrival time and / or time delay spread of reference signals in the reference signal group; sending a measurement result to the network device; and receiving indication information sent by the network device, the indication information being used for indicating a service sending reception point TRP. Therefore, the network equipment can select the appropriate TRP for the terminal equipment, and the performance of the MIMO system is improved.

This invention discloses a system and method for acoustic wireless communication that eliminates frequency-selective fading and delay spread. Addressing the problems of frequency-selective fading and delay spread in acoustic wave transmission within the water-based drilling fluid channel inside the drill pipe, it employs orthogonal frequency division multiplexing (OFDM) technology. The transmitting end includes a coding and modulation module, an OFDM modulation module, a power amplification unit, an impedance matching network, and an underwater acoustic transducer. The receiving end includes a synchronization module, a cyclic prefix removal module, a Fourier transform module, a channel estimation module, a channel equalization module, and a decoding module. The synchronization module uses the Schmidl & Cox time-frequency joint synchronization algorithm, the channel estimation module uses the MMSE frequency domain estimation algorithm based on training sequences, and the channel equalization module uses the linear MMSE frequency domain equalization algorithm. Through the co-design of hardware and algorithms, this invention effectively eliminates frequency-selective fading and delay spread, achieving high-speed, low-error-rate acoustic wireless transmission. The data transmission rate can reach 250 kbit / s, and the bit error rate can be reduced to 10%. ‑3 .

The invention discloses a channel time-frequency joint extrapolation method based on a multi-layer perceptron hybrid architecture. Aiming at the problems of high acquisition cost of actual communication scene channel data, high time consumption of model online training and difficulty in covering the actual communication scene by simulation data, the method comprises the following steps of: making a pre-training model by using a large-scale simulation channel data set to extract channel change characteristics; and carrying out online rapid adaptation according to the trace data of the actual measurement scene. Aiming at the characteristics that the time delay spread of an indoor wireless channel is relatively small and the number of antennas is relatively small, a multi-layer perceptron hybrid architecture is applied to the time-frequency domain extrapolation of a single-carrier broadband channel. The model can quickly adapt to an actual communication scene through fine tuning of a small amount of data. The method has the advantages of being high in adaptation speed, small in data dependence, high in scene migration capacity, high in calculation parallelism degree and the like, and is suitable for edge deployment and rapid adaptation to actual scenes.

The invention relates to the technical field of 5G communication channel estimation, and discloses a 5GMIMO channel estimation optimization method based on deep learning. According to the method, a deep learning model architecture is constructed, and model parameters are dynamically initialized according to channel coherence time so as to adapt to 5GMIMO channel multipath propagation characteristics. Received signal streams from a plurality of antenna elements containing different orthogonal frequency division multiplexing sub-carrier frequency sequences are processed, channel impulse response estimates are generated based on frequency domain correlation and input into a model for nonlinear transformation. And performing model parameter collaborative optimization, updating the network weight by calculating the gradient variation, constructing a target function according to channel delay extension and model depth association, and adjusting the estimation output towards the direction of minimizing the mean square error. And triggering model structure adaptation based on a norm of gradient variation, acquiring model copy parameters matched with the current channel state from an adjacent cell base station, normalizing the model copy parameters, and adjusting the number of attention heads or the number of residual blocks.

Disclosed are techniques for aliasing removal for wireless channel captures. In an aspect, a wireless station (STA) may estimate a wireless channel to produce a first frequency domain (FD) channel estimate. The STA may anti-alias the first FD channel estimate to produce a second FD channel estimate, wherein anti-aliasing the first FD channel estimate to produce a second FD channel estimate comprises removing, from the first FD channel estimate, signal energy associated with signals having a delay spread larger than a maximum tolerable delay spread. The STA may tone-decimate the second FD channel estimate to produce a third FD channel estimate. The STA may store the third FD channel estimate as a channel capture. In some aspects, the STA may send the channel capture to another entity as channel capture feedback, may performing a sensing operation using the channel capture, or both.

Granular guard interval tuning may be provided. A delay profile for a plurality of sub-bands in a serving channel may be created. Then delay spread information from at least one calibration helper device for the plurality of sub-bands in the serving channel may be received. Next, a delay spread matrix based on the delay profile, the delay spread information, and a location of the calibration helper devices may be created. The delay spread matrix may then be used to determine optimal Guard Intervals (GIs).

This disclosure provides methods, components, devices and systems for coordination for smooth beamforming. Some aspects more specifically relate to techniques to reduce phase misalignment and delay spread to beamformed messages such that a receiving device may apply channel smoothing filtering to the received beamformed message. In some examples, the transmitting device may ensure that the delay spread of the steered channel for a beamformed message is roughly matching the delay spread of an open-loop channel. The transmitting device may signal for the receiving device to perform channel smoothing filtering to a received beamformed message, for example, because the transmitting device applies techniques to reduce the phase misalignment and delay spread to the beamformed message. In some examples, based on the indication, the receiving device may apply channel smoothing filtering to a beamformed transmission received from the transmitting device.

The invention provides a channel estimation method for a minimum mean square error, which comprises the following steps of: performing Fourier transform on a received baseband signal to obtain OFDM (Orthogonal Frequency Division Multiplexing) frequency domain data, and obtaining frequency domain data of all symbols on a receiving side through solution resource mapping; the method comprises the following steps: processing by utilizing frequency domain data of a pilot symbol at a receiving side and a priori known pilot symbol sequence to obtain channel responses of SNR (Signal to Noise Ratio) estimation and LS (Least Square) channel estimation; processing according to the channel response of the LS channel estimation to obtain root-mean-square delay expansion; calculating a data-pilot frequency cross-correlation matrix and a pilot frequency self-correlation matrix according to root mean square time delay expansion, and calculating to obtain an MMSE filtering channel estimation coefficient according to the data-pilot frequency cross-correlation matrix and the pilot frequency self-correlation matrix; mMSE filtering is carried out according to the MMSE filtering channel estimation coefficient, and finally a final channel estimation value is obtained. According to the method, channel response is accurately estimated while operation is simplified, so that reliable communication and low operation delay are ensured.

A communication method and apparatus are used for improving communication performance. The method may include determining a first signal and transmitting the first signal. Wherein the first signal is determined based on a first sequence, and the first sequence is determined based on a base sequence and an extended sequence; the base sequence is a ZC periodic continuation sequence; the expansion sequence is a cyclic shift sequence, and the fuzzy function of the first sequence is equal to zero in the maximum delay spread and maximum Doppler spread range, or the expansion sequence is a cubic polynomial index sequence, and the fuzzy function of the second sequence is equal to zero in the maximum delay spread and maximum Doppler spread range. The fuzzy function of the first sequence is smaller than or equal to a fuzzy function threshold value within the maximum delay spread and the maximum Doppler spread range. The first sequence is constructed through the base sequence and the extended sequence, so that the first sequence can be used for various physical channels and physical signals, the first signal is transmitted based on the first sequence, and the communication performance can be improved.

A communication method and apparatus are used for improving communication performance. The method comprises the following steps: a first communication device determines a first signal and sends the first signal; wherein the first signal is determined based on a first sequence, and the first sequence is determined based on a base sequence and an auxiliary sequence; wherein the base sequence is an ideal autocorrelation function sequence, the auxiliary sequence is a cyclic shift sequence, and the fuzzy function of the first sequence is equal to zero in the maximum delay spread and maximum Doppler spread range; or, the base sequence is an optimal self-ambiguity function sequence, the auxiliary sequence is a quadratic polynomial exponential sequence, and the ambiguity function of the first sequence is smaller than or equal to an ambiguity function threshold within the maximum delay spread and maximum Doppler spread range. The first sequence is constructed through the base sequence and the auxiliary sequence, so that the first sequence can be used for various physical channels and physical signals, the first signal is transmitted based on the first sequence, and the communication performance can be improved.

The application discloses a kind of narrowband communication equipment detection equipment and detection method. Among them, the method includes: obtaining pre-established wireless channel model data set, the data set contains attenuation value and interference intensity distribution data under different environments;According to the attenuation value and interference intensity distribution data, a multipath propagation simulation model is constructed, a time delay spread range value is obtained by time domain analysis, and an amplitude distortion range value is obtained by frequency domain analysis;Environment noise measured data and the time delay spread range value, amplitude distortion range value are input into adaptive filtering algorithm, and signal quality evaluation data after filtering processing is generated, etc.The method of the present application analyzes and simulates the channel model data under different environments, combines various test methods and algorithms, comprehensively evaluates the performance of the equipment under various conditions, including signal quality, bit error rate, stability and risk, etc., so as to ensure the reliability of the equipment in practical application.

Methods, systems, and devices for wireless communication are described. A network entity may indicate to a user equipment (UE) the ability of the network entity to disable a power amplifier for downlink transmissions (e.g., in a downlink control message). In response to the capability indication, the UE may estimate a delay spread and antenna array loss threshold for the downlink signal and report the delay spread and antenna array loss threshold to the network entity. Based on the reported delay spread and antenna array loss threshold, the network entity may determine a number of power amplifiers that may be disabled for downlink transmissions without reducing the received signal power at the UE below a minimum threshold. The power amplifier disabled by the network entity may be a power amplifier having an input power less than a threshold (e.g., one threshold less than the highest input power).

This invention provides a method for radio frequency fingerprinting of vehicular network broadcast frames based on LMMSE channel estimation, comprising: obtaining subcarrier data in the resource grid based on the acquired signal of the physical side link broadcast channel; performing root mean square delay spreading and channel autocorrelation matrix construction based on the subcarrier data, and combining prior signal-to-noise ratio regularization and time-domain windowing operation to obtain channel estimation values; obtaining initial radio frequency fingerprint features through channel equalization and channel estimation values, and using an improved neural network and initial radio frequency fingerprint features to classify and identify vehicular network devices. This method effectively considers the impact of noise and channel on fingerprints, achieving the goal of more accurately extracting fingerprints of different devices in complex environments.

The application discloses a channel state information (CSI) measurement method, a terminal and a network side device, and belongs to the technical field of communication. The CSI measurement method comprises the following steps: a network side device sends CSI measurement configuration information to a terminal, wherein the CSI measurement configuration information is used for configuring target CSI measurement resources associated with target CSI information; and the network side device receives the target CSI information from the terminal. The target CSI information comprises at least one of the following: a Doppler frequency offset, a Doppler spread, a Doppler spectrum, a time domain channel correlation matrix, a delay spread, an average delay, a delay spectrum and a frequency domain channel correlation matrix.

This invention discloses a comprehensive evaluation method for wireless channel delay spread based on a dual correlation test in the field of wireless communication and channel modeling technology. This method includes the following steps: data acquisition and preprocessing, correlation calculation, data merging and trend analysis, and result presentation and decision-making basis. By combining Pearson and Spearman correlation coefficients, this method analyzes the impact of physical environment parameters on RMS_DS under LOS and NLOS conditions, improving the comprehensiveness and accuracy of correlation analysis and providing a reliable basis for wireless communication system design and optimization.

A device, such as a UE and a transmit / receive point (TRP), for providing network-assisted frequency offset compensation in a high-speed train single-frequency network (HST-SFN) is disclosed. The device includes a receiver that receives a first reference signal and a second reference signal transmitted from a first TRP via a wireless network. The first reference signal corresponds to the QCL RS of the second reference signal. The device receiver determines delay spread and average delay information of the path between the first TRP and the device based on the first reference signal. The device receiver also receives a third reference signal from the second TRP, which includes Doppler frequency shift and Doppler spread information and corresponds to the QCL RS of a fourth reference signal transmitted from the second TRP, or corresponds to the second reference signal transmitted from the first TRP in an SFN manner.

A communication method and apparatus, for use in improving the communication performance. The method comprises: a first communication apparatus determines a first signal and sends the first signal. The first signal is determined on the basis of a first sequence, and the first sequence is determined on the basis of a base sequence and an auxiliary sequence; the base sequence is an ideal autocorrelation function sequence, the auxiliary sequence is a cyclic shift sequence, and an ambiguity function of the first sequence is equal to zero in the range of maximum delay spread and maximum Doppler spread; or, the base sequence is an optimal self-ambiguity function sequence, the auxiliary sequence is a quadratic polynomial exponential sequence, and the ambiguity function of the first sequence is smaller than or equal to an ambiguity function threshold in the rage of maximum delay spread and maximum Doppler spread. The first sequence is constructed by means of the base sequence and the auxiliary sequence, so that the first sequence can be used for various physical channels and physical signals, and then the first signal is transmitted on the basis of the first sequence, such that the communication performance can be improved.

A generative neural network-based underwater acoustic OTFS communication transmission system and method are disclosed, relating to underwater communication transmission. Addressing the fractional spread problem caused by long delay spread and Doppler spread in broadband underwater acoustic channels, the system includes sequentially cooperating transmitter, receiver, channel estimation, and channel equalization units. The transmitter performs OTFS modulation, carrier modulation, and transmission; the receiver performs signal reception, preprocessing, and OTFS demodulation; the channel estimation unit combines a fractional-order dictionary matrix with a generative neural network, constructing a delay-Doppler domain refined grid and designing an unsupervised training model with double KL divergence constraints; and the channel equalization unit performs equalization processing and signal recovery. The method includes OTFS modulation transmission at the transmitter, underwater acoustic channel transmission, signal processing and demodulation at the receiver, generative neural network channel estimation, and equalization decoding. It requires no large number of labeled samples, has low computational complexity, short running time, and improves the transmission accuracy of underwater acoustic channels.

A terminal according to one embodiment of the present disclosure can: receive configuration information related to a wakeup signal (WUS) by means of higher-layer signaling; detect the WUS on the basis of the configuration information; determine a quasi co-location (QCL) type related to at least one from among Doppler shift, Doppler spread, average delay, delay spread and spatial Rx parameter on the basis of the capability of the terminal with respect to detection of the WUS; and detect the WUS on the basis of the QCL type.

This disclosure provides systems, apparatus, devices, and methods, including computer programs encoded on a storage medium, for switching waveforms in wireless communications. The UE (102) receives (434) a resume control message from the network entity (104) using the default waveform, the resume control message indicating a resume reference signal configuration and RACH resources. The UE (102) sends (440) a first report message on the RACH resource to the network entity (104) using the default waveform, the first report message indicating a delay spread and a Doppler spread measured from the recovery reference signal. The UE (102) receives (444) a RACH response from the network entity (104) using the default waveform, the RACH response comprising an indication of a configuration of an updated waveform for at least one of an uplink signal or a downlink signal based on the first report message.

The invention relates to the technical field of antenna switching, in particular to a CPE cellular antenna switching method and system, and the method comprises the following steps: transmitting an in-band detection signal through a service antenna at a switching interval, and constructing a current service path feature vector according to a time delay spread spectrum fed back by an adjacent base station; after executing candidate antenna switching, immediately transmitting a homologous detection signal through a current antenna, and generating a target path feature vector; and calculating the similarity between the service path feature vector and the target path feature vector, maintaining switching when the similarity is lower than a preset judgment threshold, otherwise, switching back to the original service antenna and updating the path feature library. According to the method, the fine-grained difference of the propagation path structure is reflected, the accuracy and stability of path identification are effectively improved, and the method is particularly suitable for CPE application scenes under the multi-path rich or non-line-of-sight propagation condition.

The application discloses a 6G communication signal quality optimization method and device based on intelligent traffic, and a medium, relates to the field of 6G terahertz communication technology, and can identify environment-related interference that cannot be detected by traditional methods through joint analysis of meteorological data and communication propagation path data, can track the change of interference relationship in real time, can extract the space-time characteristics of interference through the time delay extension and Doppler frequency shift of channel attenuation data, optimize the space-time joint prediction performance, model real-time space topology and time evolution based on space-time graph neural network, enhance the prediction accuracy of the model, generate an optimization strategy through an optimization strategy, can support multi-objective optimization, and can monitor the optimization result in real time during the optimization process and feed back to the model, quickly correct the model deviation, generate an interference optimization strategy, improve the comprehensiveness and accuracy of interference optimization, solve the problems of poor communication signal quality caused by static modeling, neglecting meteorology, prediction lag and strategy rigidity, and improve the communication signal quality.

The application relates to the technical field of wireless communication and machine learning cross-fusion, in particular to an industrial internet of things channel modeling method and system based on an interpretable random forest. The method comprises the following steps: constructing a channel data set containing multiple industrial scenes, a receiving point line-of-sight state and a three-dimensional position; after joint environment-height balance sampling and standardization preprocessing, a multi-output regression model is established by using a random forest, system parameters are taken as inputs, and a root mean square delay spread, an azimuth spread and an elevation spread are jointly predicted; further, the model efficiency and precision are improved by using a hyperparameter optimization with a time penalty term, and the model decision mechanism is explained from a global and local level by using permutation feature importance and SHAP value analysis, and the consistency with a physical propagation law is verified. The application realizes high-precision, stable and interpretable joint prediction of key statistical characteristics of an industrial wireless channel, and can support channel modeling, network planning and optimized deployment of an industrial internet of things communication system.

A communication method and apparatus, which are used for improving communication performance. The method may comprise: determining a first signal, and sending the first signal, wherein the first signal is determined on the basis of a first sequence, and the first sequence is determined based on a base sequence and an extension sequence; the base sequence is a ZC periodic extension sequence; if the extension sequence is a cyclic shift sequence, the ambiguity function of the first sequence is equal to zero within the ranges of a maximum delay spread and a maximum Doppler spread; alternatively, if the extension sequence is a cubic polynomial exponential sequence, the ambiguity function of the first sequence is less than or equal to an ambiguity function threshold within the ranges of the maximum delay spread and the maximum Doppler spread. A first sequence is constructed on the basis of a base sequence and an extension sequence, such that the first sequence may be used for various physical channels and physical signals, and thus a first signal is transmitted on the basis of the first sequence, and the communication performance can be improved.

A method (400, 500) for an apparatus, such as a User Equipment, UE, (110) and a Network Entity, NE, (120), in a wireless network provides a mechanism for overhead reduction for uplink precoder indication when some of the groups of UE antenna ports have substantially the same channel properties. The channel properties may be one or more of quasi-co-location correlation properties, including delay spread, average delay, Doppler spread, Doppler shift, spatial transmission filter, or average gain. These mechanisms may be employed when the operability of one or more antenna ports changes.