34 results about "Channel reciprocity" patented technology

The present disclosure relates to apparatus, methods, computer-readable storage medium and computer program product for CSI-RS enhancement for Port Selection Codebook with Channel Reciprocity. A cellular base station, comprising: at least one antenna; at least one radio coupled to the at least one antenna; and a processor coupled to the at least one radio; wherein the cellular base station is configured to: provide a Radio Resource Control (RRC) message to a wireless device; and provide a Channel State Information-Reference Signal (CSI-RS) to the wireless device via one or more ports based on the RRC message, wherein, the RRC message at least indicates one or more of: information on a density of the CSI-RS, information on time domain locations of the CSI-RS, information on a subset of ports for the wireless device to measure the CSI-RS, and information on a subset of Code Division Multiplexing (CDM) groups for the wireless device to measure the CSI-RS.

The invention provides a communication method and a related device. In the method, a terminal determines a time coherence degree of one or more sub-band groups based on N CSI reports, determines first information based on the time coherence degree of one or more sub-band groups and a first duration, and sends the first information to a network device, the first information being used for indicating a confidence coefficient of each sub-band group or a confidence coefficient of a broadband corresponding to each sub-band group, the confidence coefficient of the sub-band group is the confidence coefficient of the channel reciprocity between the uplink and downlink channels of the sub-band group, and the confidence coefficient of the broadband is the confidence coefficient of the channel reciprocity between the uplink and downlink channels of the broadband corresponding to the sub-band group. Under the condition that the network equipment determines the downlink channel characteristics according to the first information, the uplink channel estimation result and the downlink channel estimation result from the terminal, the accuracy of the downlink channel characteristics obtained based on channel reciprocity can be improved.

The application discloses a channel state information compensation method, a communication device and a computer program product. It relates to the technical field of network communication, and the method comprises the following steps: acquiring a target moving speed of relative motion between a first device and a second device, and a plurality of channel estimation results of a channel between the first device and the second device; determining a target nonlinear interpolation coefficient corresponding to the target moving speed based on a corresponding relationship between the moving speed and the nonlinear interpolation coefficient; and compensating channel state information of the channel based on the plurality of channel estimation results and the target nonlinear interpolation coefficient to obtain a channel state information compensation result. The application solves the technical problem that in the related art, the channel considered when performing channel compensation is mostly a channel in a static or slow moving environment, and in the case that the terminal moving speed is relatively high, the channel has strong time variation, the channel reciprocity is poor, and the channel compensation accuracy is low.

The application discloses a kind of based on affine frequency division multiplexing covert communication method and system.The method includes: transmitting end and receiving end respectively carry out channel estimation, obtain channel state information, and construct frequency domain channel matrix;Using channel reciprocity, both sides independently generate the same Chirp parameter codebook, avoid eavesdropper reconstruction;Transmitting end generates corresponding modulation symbol according to the input modulation bit;According to the amplitude of the diagonal element of frequency domain channel matrix, index bit is selected to the starting position of the Chirp parameter codebook;Transmitting end carries out affine frequency division multiplexing modulation according to the Chirp parameter codebook selected by index bit to constellation symbol and transmits;Receiving end reconstructs Chirp parameter codebook using its own CSI and completes matching decoding and modulation decryption.The application realizes shared password book without the need of privacy information exchange, makes full use of waveform parameter degree of freedom, improves the spectral efficiency and communication security of system, and is suitable for high-speed mobile communication data covert transmission.

Techniques are provided for implementing time-inverted reference signals for radio frequency (RF) sensing operations in a communication system. An example method for generating channel reciprocity information for a radio frequency sensing operation includes receiving radio frequency sensing information from a sensing node; generating a channel reciprocity prediction based at least in part on the radio frequency sensing information and a channel reciprocity prediction model; and providing an indication for time reversal precoding to the sensing node based on the channel reciprocity prediction.

The invention belongs to the technical field of wireless communication, and discloses a cellular-removed large-scale MIMO distributed dual-time-scale hybrid precoding method, which comprises the following steps of: constructing a user average channel covariance matrix at each access point (AP); carrying out eigenvalue decomposition on the user average covariance matrix and extracting a main eigenvector to construct an initial simulation precoding matrix; performing constant modulus constraint processing on the initial analog precoding matrix to obtain an analog precoding matrix; a user sends an orthogonal pilot frequency, each AP carries out instantaneous channel state information estimation by adopting a minimum mean square error criterion, and a downlink channel is obtained based on the reciprocity of uplink and downlink channels; each AP designs a digital precoding vector according to a downlink channel; the AP allocates power to the user according to the power constraint; system spectral efficiency is calculated to assess method performance. According to the method, the expandability of the system is effectively improved while the channel estimation overhead and the operation complexity are reduced, and the method is suitable for efficient implementation of the honeycomb-removed large-scale MIMO system.

The present application relates to the technical field of communications, and provides a method and apparatus for determining a channel calibration coefficient. The method comprises: on a first channel, sending a first reference signal to a second apparatus, wherein the first reference signal is used for determining a first parameter, and the first parameter is used for indicating a response matrix of the first channel; on a second channel, receiving a second reference signal from the second apparatus, wherein the second reference signal is used for determining a second parameter, and the second parameter is used for indicating a response matrix of the second channel; on the second channel, receiving a third reference signal from the second apparatus, wherein the third reference signal is precoded on the basis of the first parameter, and the third reference signal is used for determining the first parameter; and on the basis of the first parameter and the second parameter, determining a third parameter, wherein the third parameter is used for calibrating the reciprocity between the second channel and the first channel. In the solution, a channel reciprocity calibration coefficient is determined with low complexity by means of simple air interface interaction.

The invention belongs to but is not limited to the technical field of optical key distribution, and discloses a communication and encryption integrated key distribution system and method based on channel reciprocity and coherent optical communication, which utilizes a scrambler to enable the tap coefficient of a time-varying depolarization algorithm to change quickly, thereby improving the key generation rate and improving the key transmission efficiency. And the method is combined with a channel reciprocity characteristic and is applied to secure key distribution. According to the invention, key distribution and secure coherent light communication can be carried out simultaneously. And during digital signal processing of the signal receiving module, on one hand, key generation is carried out, and on the other hand, secure optical communication is carried out. It is guaranteed that two legal parties obtain consistent secret keys through dynamic reciprocity of channels, and safety is guaranteed through mutual disturbance of the channel reciprocity and a time-varying cross-polarization state. The system does not need additional devices and is highly compatible with the current coherent communication system, so that the deployment cost of the key distribution module can be reduced.

The invention provides a channel calibration coefficient determination method and device, and relates to the technical field of communication. The method comprises: on a first channel, sending a first reference signal to a second device, the first reference signal being used to determine a first parameter, the first parameter being used to indicate a response matrix of the first channel; on a second channel, receiving a second reference signal from the second device, the second reference signal being used to determine a second parameter, the second parameter being used to indicate a response matrix of the second channel; on the second channel, receiving a third reference signal from the second device, the third reference signal being subjected to precoding processing based on the first parameter, the third reference signal being used for determining the first parameter; and determining a third parameter according to the first parameter and the second parameter, the third parameter being used for calibrating the reciprocity of the second channel and the first channel. According to the scheme, the channel reciprocity calibration coefficient is determined with relatively low complexity through simple air interface interaction.

The application discloses a channel information compression feedback method using frequency division duplex channel implicit reciprocity. For the frequency division duplex channel information data with implicit reciprocity, the application firstly converts the spatial frequency domain channel matrix to the angle delay domain and performs clipping, and then splits and splices the real part and the imaginary part of the channel matrix into two real number matrices; three encoder networks are used for decoupling characterization learning of the downlink channel, and the downlink channel unique information, the uplink and downlink channel common information and the virtual uplink and downlink channel common information are extracted respectively; the decoder network recovers the original channel information by using the downlink channel unique information and the uplink and downlink channel common information during training, and recovers the original channel information by using the downlink channel unique information and the virtual uplink and downlink channel common information during testing; in the application, the user only needs to feed back the downlink channel unique information, the channel feedback load is effectively reduced, the channel information recovery performance is improved, and the application has a significant performance advantage.

The invention provides a communication method and a communication device, and relates to the field of communication. In the method, a terminal device can obtain first channel information and second channel information, the first channel information is channel information of an uplink channel between a network device and the terminal device, and the second channel information is channel information of a downlink channel between the network device and the terminal device; and then the terminal equipment can determine a correction coefficient of an antenna of the terminal equipment according to the first channel information and the second channel information, and the correction coefficient is a channel reciprocity correction coefficient. Based on the scheme, the reciprocity correction of the receiving and transmitting channels of the terminal equipment can be realized.

The application provides a lattice public key encryption method and device based on a super large scale MIMO, which is composed of a physical layer public key encryption and a private key decryption. A base station jointly completes encryption and SVD precoding operation with a channel matrix and a public key. A legal user terminal completes key generation and decryption operation. The legal user terminal generates a private key based on a lattice orthogonal basis; based on the private key and the orthogonal basis, a nearest plane algorithm operation is performed on noisy encrypted information, and finally decryption is realized. When the number of antennas of an eavesdropper is infinite and much larger than the number of antennas of a legal terminal, when the distance between the eavesdropper and the legal terminal is less than one half of the wavelength, or when the channel estimation process is directly attacked to obtain legal channel information, the application is also secure. The application can be simultaneously applied to time division duplex and frequency division duplex channels, does not need to rely on channel reciprocity and is based on lattice cryptography, can resist current known quantum attacks, and meets the requirements of future 6G for communication security.

Systems and methods are described for radio frequency (RF) calibration in a multiple antenna system (MAS) with multi-user (MU) transmissions (“MU-MAS”) exploiting uplink / downlink channel reciprocity. The RF calibration is used to compute open-loop downlink precoder based on uplink channel estimates, thereby avoiding feedback overhead for channel state information as in closed-loop schemes. For example, a MU-MAS of one embodiment comprises a wireless cellular network with one or multiple beacon stations, multiple client devices and multiple distributed antennas operating cooperatively via precoding methods to eliminate inter-client interference and increase network capacity.

The methods (800, 900) and apparatuses (310, 320) enable (834, 934) measurement of downlink reference signals to report (840, 940) values of a subband layer 1 signal-to-interference-and-noise ratio, a subband interference level, and / or a subband layer 1 reference signal received power for each of at least two subbands. These values are used to enhance selection of a modulation and coding scheme and a number of downlink transmission layers. Uplink sounding reference signals are also used to measure and report subband values that lead to this selection, assuming channel reciprocity.

Methods, systems, and devices for wireless communications are described to reduce a quantity of blind decodes performed at a user equipment (UE) when monitoring for downlink control information from a network entity. The quantity of blind decodes at a UE may be reduced through selection of a subset of a set of candidates based on a channel condition associated with two or more candidates of the set of candidates. Channel reciprocity for uplink and downlink channels may provide that the network entity may evaluate the downlink channel response experienced by the UE by measuring the reciprocal uplink channel such that the network entity selects a same candidate, or one of two or more candidates in a subset of candidates. The UE may use downlink channel measurements to select a blind decoding candidate, or subset of candidates, that corresponds to the candidate selected by the network entity.

The application discloses a kind of channel compensation processing method, communication device and computer program product.It relates to network communication technical field, the method includes: obtaining the target moving speed of relative motion between first device and second device, multiple channel estimation results of channel between first device and second device;Based on multiple channel estimation results, the channel state information of channel is compensated using interpolation method, and target intermediate compensation result is obtained;With target moving speed and target intermediate compensation result as input, the channel state information of channel is compensated using channel state information prediction model, and target channel state information compensation result is obtained.The application solves the technical problems that in the related art, when channel compensation is carried out, the channel in static or slow moving environment is considered, in the case where terminal moving speed is relatively fast, channel has strong time-varying, channel reciprocity is poor, and channel compensation accuracy is low.

The invention discloses a dynamic physical layer key generation method and system based on satellite channel reciprocity, and relates to the technical field of wireless communication physical layer security, and the method comprises the steps: calculating a relative radial speed based on the motion state parameter of a communication node, and estimating the maximum Doppler frequency shift; calculating the change rate of channel impact response through real-time channel measurement so as to evaluate the channel randomness; binary decision is carried out based on a quantitative reciprocity evaluation model, and a physical layer key generation mode or a standby security mode is started for dynamic decision; when a physical layer key generation mode is decided to be started, performing anti-frequency-offset joint detection and synchronization, extracting a multi-dimensional channel feature containing a multipath component, performing adaptive quantization according to a signal-to-noise ratio, performing information negotiation based on hybrid coding of an LDPC code and an LT code to correct inconsistency, and performing privacy enhancement processing to generate a final session key. Through dynamic decision and a complete signal processing flow, high-reliability and high-efficiency physical layer key generation of the satellite is realized.

Aspects of the disclosure relate to communications using a multi-panel base station. In an aspect, a base station can determine a plurality of indicators identifying a plurality of antenna panels on the base station, where each of the plurality of indicators identifies a respective antenna panel of the plurality of antenna panels. Further, the base station can transmit, to a user equipment (UE), the plurality of indicators identifying the plurality of antenna panels, respectively. Additional aspects of the disclosure relate to communications using a user equipment. In an aspect, a user equipment can receive, from a base station configured to communicate via a plurality of panels, a plurality of indicators identifying a plurality of antenna panels, respectively, and further, the user equipment can transmit, to the plurality of antenna panels of the base station, a plurality of sounding reference signals based on the plurality of indicators.

Embodiments of the present application disclose a weight value determination method and related apparatus, which are used to reduce beam gain loss caused by beam selection bias. The method of the embodiments of the present application comprises receiving an uplink reference signal, obtaining a channel reciprocity parameter between an uplink channel and a downlink channel based on the uplink reference signal, determining state information of the downlink channel according to the channel reciprocity parameter and carrier frequency information of the uplink channel and the downlink channel, and determining a weight value of a downlink reference signal according to the state information of the downlink channel.

This application provides a method, apparatus, electronic device, and storage medium for encrypted communication in a vehicle-to-everything (V2X) network. The method includes: sending first communication data to a second terminal according to a preset communication protocol and receiving second communication data sent by the second terminal; determining filter parameter information based on the second communication data; constructing a filter based on the parameter information; inputting the second communication data into the filter to obtain predicted communication data; generating a first key based on the predicted communication data; encrypting target information using the first key and sending the encrypted target information to the second terminal; the second terminal is used to generate a second key based on the first communication data; and decrypting the target information based on the second key. This V2X encrypted communication method improves channel reciprocity and increases the key consistency rate between the communicating parties.

This application provides a neural network training method and a communication apparatus. The method may include: A first device sends a first signal; a second device determines a second signal and an intermediate gradient, and sends the second signal and the intermediate gradient to the first device, where the second signal is correlated with the first signal; and the first device receives the intermediate gradient and the second signal, corrects the intermediate gradient based on the first signal and the second signal, and further updates a neural network parameter based on a corrected intermediate gradient. In this way, training of a neural network can be more efficient, and the training of the neural network can also be implemented by using the method in this application even in a communication scenario in which channel reciprocity is poor.

The application relates to the technical field of wireless communication, in particular to a 5G base station signal dynamic optimization method and system. The method comprises the following steps: acquiring multi-dimensional running state data of each radio frequency channel of a base station; performing correlation analysis on the multi-dimensional running state data based on a preset combination judgment rule; when the correlation analysis simultaneously satisfies the combination condition, determining that the radio frequency channel has suspected reciprocity failure; performing a controlled power down test on the radio frequency channel determined as the suspected reciprocity failure, monitoring the index change trend in real time, and distinguishing the fault root cause according to a preset response relationship; if it is determined that the fault root cause is temperature-induced reciprocity failure, injecting two downlink probe signals to obtain a real phase offset value, and generating a temperature phase compensation corresponding relationship table; matching the phase compensation value in real time, and outputting an optimized beamforming result. The method has the advantages that the uplink and downlink channel reciprocity failure can be effectively identified and solved, and the beamforming precision and user service quality are significantly improved.

A method performed by a reader for paging identity protection in an ambient intemet-of-things (AIoT) communication system includes paging an AIoT device using an initial paging identifier, generating, based on wireless channel reciprocity characteristics, a random number, deriving, using the random number and the initial paging identifier, a paging identifier, and replacing the initial paging identifier with the paging identifier for subsequent paging of the AIoT device.

This invention proposes a dual reconfigurable smart surface (RIS)-assisted "one-time pad" secure wireless communication method to address the problems of low physical layer key generation rate and insufficient key rate to meet the requirements of one-time pad data transmission in wireless communication. This method constructs a controllable-random channel environment by deploying two N-unit RISs. It utilizes a multi-agent reinforcement learning (MARL) algorithm to jointly optimize the RIS phase shift and the number of key negotiation rounds, achieving a dynamic balance between data transmission rate and key generation rate. Based on this, it achieves absolutely secure communication for one-time pad data transmission. First, the legitimate communicating parties (Alice and Bob) construct a multipath random wireless channel by controlling the dual RISs based on channel reciprocity in time-division duplex (TDD) mode. Second, the MARL algorithm (including a pre-training mechanism) is used to control and optimize the phase shift of the dual RISs and determine the optimal number of key negotiation rounds for one-time pad. Finally, the physical layer key is generated through channel probing, channel estimation, quantization negotiation, and privacy amplification. Before data transmission, the generated key is used to XOR the transmitted data, achieving lightweight encryption of the transmitted data. This method significantly improves the physical layer key generation rate, provides a feasible solution for realizing "one-time key" data transmission, and is applicable to various wireless security communication scenarios such as the Internet of Things, the Internet of Vehicles, and satellite communication. It can take into account both the complexity of edge device deployment and real-time requirements.

The application belongs to the technical field of optical secret communication and optical signal processing, and discloses a secure key distribution device, a control method, a medium and computer equipment, the secure key distribution device comprising: a first optical signal initialization module, a first wideband digital chaos signal module, a first orthogonal polarization modulation module, a first secure key extraction module, an optical fiber channel transmission module, a second optical signal initialization module, a second wideband digital chaos signal module, a second orthogonal polarization modulation module and a second secure key extraction module. The application combines polarization multiplexing chaos modulation and optical fiber channel reciprocity characteristics and applies them to secure key distribution, which can effectively improve the secure key distribution rate and the stability of the distribution process rate, realize high-security physical layer secure key distribution with long-term stability, and provide security for the secure key distribution process because the optical fiber channel characteristics shared by both parties change over time and are difficult for eavesdroppers to obtain.

Provided is a method and system for multimodal learning-based frequency division duplexing (FDD) massive multiple-input multiple-output (MIMO) downlink channel estimation. The multimodal learning-based FDD mMIMO downlink channel estimation system includes a multi-modality selector configured to select multi-modal data for deep learning based on a partial channel reciprocity to estimate a channel of an FDD mMIMO system; a preprocessing unit configured to preprocess the selected multi-modal data to training data for channel estimation; a multimodal deep neural network (DNN) modeling unit configured to perform multimodal DNN modeling based on a multimodal knowledge distillation technique for solving a modality laziness problem using the preprocessed multi-modal data; and a multimodal DNN training unit configured to estimate a downlink channel of the FDD mMIMO system by training a multimodal DNN model.

The invention belongs to but is not limited to the technical field of optical key distribution, and discloses a communication and encryption integrated key distribution system and method based on channel reciprocity and error rate estimation, and a distribution device comprises a first signal transmitting module, a second signal transmitting module, a channel transmission module, a first signal receiving module and a second signal receiving module. According to the method, the time-varying bit error rate is rapidly changed by using the scrambler, so that the key generation rate is improved, and the method is combined with the channel reciprocity characteristic and is applied to secure key distribution. According to the invention, key distribution and secure optical communication can be carried out simultaneously. In the signal receiving module, the signal is divided into two parts by power: the first part is used for key generation, and the second part is used for secure optical communication. And a polarization analyzer is added to the second part, the error rate is higher than the error rate during secure transmission, encoding and decoding are carried out by using error correction code parameters which are negotiated to be consistent, and an estimated error rate sequence is obtained by comparing information bits in an error-corrected bit sequence with information bits in a receiving sequence.

The application provides a communication method and related device. In the method, a terminal determines time coherence of one or more sub-band groups based on N times of CSI reporting, determines first information based on the time coherence of the one or more sub-band groups and a first time length, and sends the first information to a network device, the first information being used to indicate confidence of each sub-band group or confidence of a wide band corresponding to each sub-band group, the confidence of the sub-band group being confidence of channel reciprocity between uplink and downlink channels of the sub-band group, and the confidence of the wide band being confidence of channel reciprocity between uplink and downlink channels of a wide band corresponding to the sub-band group. In a case where the network device determines downlink channel characteristics according to the first information, uplink channel estimation results and downlink channel estimation results from the terminal, the accuracy of the downlink channel characteristics obtained based on the channel reciprocity can be improved.

Some wireless communications systems may perform artificial intelligence or machine learning (AI / ML)-based positioning, which may improve positioning accuracy in stringent non-line-of-sight (NLOS) conditions. Utilization of AI / ML-based positioning may rely on information for AI / ML model training or information for monitoring AI / ML-based positioning performance. One way to reduce the burden of data collection at the user equipment (UE) side may rely on uplink and downlink channel reciprocity. Channel reciprocity may be a condition where a channel may exhibit similar (e.g., the same) characteristics in different directions (e.g., uplink and downlink directions). Based on channel reciprocity, an AI / ML model trained with information obtained based on measurements in one direction may be utilized for prediction in another direction. For instance, downlink measurements may be utilized to train an AI / ML model that may be utilized for inference based on uplink measurements using part A or part B.

Provided in the present application are a communication method and a communication apparatus, relating to the field of communications. In the method, a terminal device may acquire first channel information and second channel information, where the first channel information is channel information of an uplink channel between a network device and the terminal device, and the second channel information is channel information of a downlink channel between the network device and the terminal device, and then, the terminal device may determine a calibration coefficient of antennas of the terminal device on the basis of the first channel information and the second channel information, where the calibration coefficient is a channel reciprocity calibration coefficient. The described solution can implement reciprocity calibration of transmit and receive channels of terminal devices.