120 results about "Delay spread" patented technology

The invention discloses a multi-modal data sensing processing method and system for a sound intelligent film, and relates to the technical field of data processing. By constructing the modal state transition diagram and the spatial position matrix, the abnormal state and the interference area can be accurately identified, and the processing strategy is dynamically adjusted, so that the response speed and the processing flexibility of the system to the abnormal modal data are effectively improved. Particularly, under the condition that interference data is frequently transmitted or bandwidth resources are limited, data transmission and calculation burdens are greatly reduced through a modal compression and delay decoding mechanism, and continuity and stability of a main processing stream are guaranteed. Meanwhile, the method has high adaptive capacity, cache management and path priority can be dynamically adjusted according to real-time state changes, and data congestion and delay diffusion are effectively prevented.

The invention discloses a wireless radio frequency data monitoring and distribution platform system and method based on data analysis, and belongs to the technical field of wireless communication. Wireless radio frequency signal parameters are acquired, data processing is performed on the signal parameters, a signal evaluation model is constructed, and the signal parameters are imported into the signal evaluation model to evaluate the signal-to-noise ratio. Constructing a channel occupation and multipath time delay extension evaluation model, importing the channel occupation time and the power and time delay of the multipath channel into the channel occupation and multipath time delay extension evaluation model to evaluate the signal condition, and constructing an equipment interference model; the method comprises the following steps: importing signal parameters and position distances of field working equipment into an equipment interference model to evaluate the interference degree of the working equipment on a wireless radio frequency transmission signal, constructing an optimal frequency band scoring model, and importing a signal-to-noise ratio, a channel occupancy rate, multipath time delay extension and equipment interference conditions into the optimal frequency band scoring model to perform frequency band selection. And the reliability and the real-time performance of wireless communication in an industrial scene are improved.

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.

A communication device receives, from another communication device, a set of transmissions over a sidelink shared channel, or over a downlink shared channel (1005). The communication device estimates a Doppler spread or a delay spread based on the received set of transmissions over the shared channel (1010). The communication device selects a reference signal configuration, from multiple reference signal configurations, based on the estimated Doppler spread or the estimated delay spread (1015). The reference signal is a DMRS, a PTRS and / or a TRS. Finally, the communication device transmits feedback indicating the selected reference signal configuration for a subsequent set of transmissions over the shared channel (1020).

The invention discloses narrowband communication equipment detection equipment and a detection method. The method comprises the steps that a pre-established wireless channel model data set is acquired, and the data set comprises attenuation values and interference intensity distribution data in different environments; constructing a multipath propagation simulation model according to the attenuation value and the interference intensity distribution data, obtaining a time delay extension range value by adopting time domain analysis, and obtaining an amplitude distortion range value by combining frequency domain analysis; and inputting actual measurement data of the environmental noise, the time delay extension range value and the amplitude distortion range value into an adaptive filtering algorithm to generate signal quality evaluation data after filtering processing, and the like. According to the method, through analysis and simulation of channel model data in different environments, various test means and algorithms are combined, and the performance of the equipment under various conditions, including signal quality, bit error rate, stability, risk and the like, is comprehensively evaluated, so that the reliability of the equipment in practical application is ensured.

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.

The invention discloses a power line carrier and wireless dual-mode fusion communication method, which relates to the technical field of communication, and comprises the following steps: synchronously acquiring a three-phase power line carrier signal and a wireless signal, and generating a wireless available spectrogram; a plurality of power line basic modes are separated from the power line carrier signals, power line effective modes are screened out after mode effectiveness judgment, and orthogonality loss degrees and phase deviations of the power line effective modes are combined into power line feature vectors; based on the wireless available spectrogram, a wireless basic mode is generated, access condition screening is carried out, a wireless effective mode is screened out, and time delay spread and spectral efficiency of the wireless effective mode are combined into a wireless feature vector; the method comprises the following steps: constructing a similarity matrix, taking the similarity matrix as a cost matrix, matching an optimal mode pair of a power line effective mode and a wireless effective mode, determining a modulation mode according to a matching result, and solving the limitation of multipath phase distortion, spectrum conflict and static channel estimation.

A receiving apparatus includes: M receivers configured to receive signals based on sound waves propagating in water; M FIR filters configured to perform waveform operation on the signals received by the receivers; a combiner configured to combine output signals of the M FIR filters; and a filter coefficient calculation portion configured to calculate a tap coefficient of the M FIR filters so as to reduce an error of the output signals combined by the combiner. The M FIR filters have a tap length that is shorter than a delay spread that is a possible range between a time of arrival of a direct wave and a time of arrival of a delayed wave of the sound waves.

A wireless transmit / receive unit (WTRU) may receive configuration information that indicates one or more of a first transmission configuration indicator (TCI) state, a second TCI state, a first cyclic prefix (CP) size, a first channel state information-reference signal (CSI-RS) resource set, and a second CSI-RS resource set. The WTRU may determine a first delay spread and a first measurement value associated with a first CSI-RS. The WTRU may determine a second delay spread and a second measurement value associated with a second CSI-RS. The WTRU may send a first indication indicating whether the first delay spread is greater than or less than the first CP size.

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.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may first delay value associated with a small delay cyclic delay diversity (CDD) scheme for a broadcast channel. In some examples, the first delay value may be selected from a set of candidate delay values based on a frequency band associated with the broadcast channel. The UE may perform channel estimation for the broadcast channel in accordance with one or more delay spread values associated with a multi-path profile of the broadcast channel, where the one or more delay spread values are based at least in part on the first delay value associated with the small delay CDD scheme. The UE may receive a message via the broadcast channel based at least in part on performing the channel estimation.

The invention particularly relates to a maximum delay spread estimation optimization method in a wireless ad hoc network. According to the maximum delay spread estimation optimization method in the wireless ad hoc network, after a signal r is received, the conjugate product h of a pilot frequency position signal and a reference symbol is calculated firstly, then the frequency domain correlation Corr and the product f (m) of the frequency domain correlation and a filter coefficient are calculated, post-processing is conducted on the product f (m), and the gear of maximum delay spread is selected; when the maximum delay spread gear of the continuous A subframes is not changed and the receiving node number is not changed, reducing the estimation frequency of the maximum delay spread; and when the estimation result changes or the receiving node number changes, the estimation of the maximum delay spread in each sub-frame is restarted. According to the maximum time delay spread estimation optimization method in the wireless ad hoc network, time delay spread areas can be clearly divided in different scenes, the maximum time delay spread of a channel is further estimated, the calculation complexity is reduced, and the calculation error-tolerant rate is also improved.

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.

The invention provides a channel estimation method based on a double-domain weighting-noise threshold, which comprises the following steps of: 1, time-frequency domain transformation: after receiving signals of a receiving end are subjected to time-frequency synchronization processing, extracting a pilot frequency sequence pilot, carrying out N-point FFT (Fast Fourier Transform) on the receiving signals, and converting the receiving signals to a frequency domain to obtain PILOT; performing N-point FFT (Fast Fourier Transform) on the time domain local pilot frequency sequence pilot to generate a frequency domain local pilot frequency PILOT; 2, calculating a frequency domain weighting coefficient: calculating the frequency domain weighting coefficient Coef according to the local pilot frequency PILOT and the current linear signal-to-noise ratio sn; step 3, channel estimation calculation: carrying out signal-to-noise ratio self-adaptive adjustment on the received signal of each frequency point through the operation; 4, inverse discrete Fourier transform: performing inverse Fourier transform on the channel estimation H after frequency domain weighting, and converting a frequency domain signal into a time domain signal to obtain h; step 5, extracting useful information: calculating and determining an optimal symbol length parameter L according to the maximum time delay extension of the system, performing optimization truncation on time domain data, retaining original values of the first L sampling points, endowing a zero value to subsequent sampling data exceeding the L point, and finally obtaining an optimized time domain result hL; 6, threshold judgment: within the range of the effective symbol length L, calculating a self-adaptive noise judgment threshold, implementing intelligent noise filtering processing on the truncated L-point data by using the threshold, eliminating a noise component through the threshold, and finally outputting a purified result hLR; and 7, zero padding: setting the length of the data block needing to be balanced as M, and setting the point number of channel estimation as N. When Mgt; when M is larger than N, time domain zero padding needs to be carried out on the hLR, the number of zero padding is M-N, and hLRZ is obtained; and 8, DFT: carrying out Fourier transform on the hLRZ to obtain a final complete channel estimation HLRZ.

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 discloses a double-branch CSI feedback compression method in a UAV (unmanned aerial vehicle) system, which comprises the following steps: the UAV extracts sensing information according to a GNSS (global navigation satellite system) chip to obtain maximum delay expansion and maximum Doppler frequency shift; the UAV performs two-step error suppression based on the sensing information: initial error suppression and threshold-based error suppression; the UAV designs a double-branch compression feedback scheme based on the sensing information: a CF branch and an EF branch to obtain a final feedback vector; and the BS designs a double-branch reconstruction algorithm for different branches to obtain reconstructed CSI. According to the invention, the precision of downlink CSI is improved at a feedback source, and the feedback overhead is reduced by using a double-branch compression scheme; according to the method and the device, the CSI is optimized by the UAV by utilizing the sensing information, so that the calculation complexity of CSI reconstruction is reduced under the condition that the BS does not increase extra resource consumption, and the recovery precision of the CSI is improved.

The invention discloses an information configuration method, a terminal and network side equipment, and belongs to the field of communication, and the information configuration method comprises the steps that the terminal receives first configuration information; wherein the first configuration information is used for configuring at least one of the following items: at least one first time unit type corresponding to at least one first time unit, and a combination mode of the at least one first time unit type; any one of the at least one first time unit type comprises any one of the following items: a cyclic prefix (CP) type or a CP length. According to the method, the flexibility of the time domain format of at least one first time unit can be improved, that is, the requirements of different transmission data, application scenarios or terminal types on CP types or CP lengths can be met, so that inter-symbol interference caused by channel delay extension or time-frequency offset synchronization can be reduced, and the user experience can be improved. And the problem of low resource efficiency caused by the cyclic prefix can be reduced.

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.

An apparatus and method to receive a time / frequency tracking signal in a wireless communication network such as a 5G New Radio (NR) network. A user equipment (UE) receives from a network node a refe

The present invention discloses an underwater acoustic orthogonal frequency division multiplexing secure communication method. The multiple transmit time reversal pre-filtering at the transmitter focuses the energy of the legitimate channel on the main path, shortening the channel of the cooperating party, while the eavesdropper still exhibits severe multipath characteristics. An orthogonal frequency division multiplexing signal with a short cyclic prefix smaller than the channel delay spread is transmitted, causing severe inter-symbol interference and inter-carrier interference to the eavesdropper. At the legitimate receiver, an interference cancellation-decision feedback equalizer is used to eliminate the residual interference of the cooperating party, improving the quality of the communication link of the cooperating party. Moreover, the secrecy capacity expression of the proposed method is given to evaluate the security performance of the system. The present invention is suitable for the underwater acoustic environment and has good performance in the long-delay frequency-selective underwater acoustic channel. When the location and channel information of the eavesdropper are both unknown, a considerable secrecy rate is obtained without the assistance of artificial noise.

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 resource allocation method and a related device. In the resource allocation method provided by the application, the network device indicates the Doppler spread and / or the time delay spread of each DMRS in the at least one DMRS to the terminal device through the first information, equivalently, the DD domain resource matching the Doppler spread demand and / or the time delay spread demand of each DMRS is allocated for each DMRS, thereby reducing the resource overhead of the DMRS and improving the resource utilization rate.

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.

The present invention discloses a method and system for processing rail transit operation and maintenance status data based on artificial intelligence, which specifically relates to the field of rail operation and maintenance management technology, and is used to solve the problem that the existing tunnel area of ​​rail transit cannot be discovered in advance. The tunnel area is divided into a complex area and an ordinary area. When the train is in the ordinary area, the delay spread caused by the complex reflection path and the spectrum expansion caused by the dynamic Doppler shift are evaluated by analyzing the high-precision channel impulse response estimation results and the signal time-varying spectrum characteristics, and it is judged whether the signal transmission is normal; in the complex area, it is first judged whether the tunnel curvature and the cross structure cause signal shielding and sudden fading. If there is no shielding, the signal distortion caused by electromagnetic resonance is evaluated by analyzing the high-order statistical characteristics. Finally, the signal delay diffusion degree and the electromagnetic resonance distortion degree are comprehensively analyzed to evaluate the potential risk of signal transmission.

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.