250 results about "Channel gain" patented technology

The invention discloses a method for estimating the safety communication rate of a near-earth satellite by using an SDFS cooperating with a GLRT. The method comprises the following steps: constructing a communication system model between the near-earth satellite and a ground terminal; analyzing the signal and channel characteristics, and obtaining the distance between the nodes, the channel gain and the received signal distribution; under the condition that the transmitting power of each monitoring party is unknown, estimating the transmitting power by adopting generalized likelihood ratio test, and independently executing the generalized likelihood ratio test based on the observation data of each monitoring party; the superior manager performs joint judgment based on a soft decision fusion scheme in combination with the generalized likelihood ratio test result of each monitoring party and a joint threshold so as to estimate the detection error probability of the monitoring party; a joint optimization strategy of the transmitting power and the number of continuous transmission time slots is constructed, and the total throughput of the system is maximized under the condition that the cooperative concealment constraint is met; according to the invention, an innovative solution is provided for reliable communication of the near-earth satellite in a complex monitoring environment.

The invention discloses an intelligent adaptive metasurface and an electromagnetic regulation and control method. The metasurface unit is of a three-layer composite structure and comprises a programmable phase shifter, a slot antenna and a coupling circuit, and real-time sensing of amplitude and phase information of incident electromagnetic waves and 0-360-degree continuous regulation and control of reflection phases are achieved. The array is composed of 6 * 6 independent control units and supports + / -60-degree beam scanning and high-precision direction of arrival estimation (error lt; 1 degree). Channel state information is obtained through a coupling link, a coding matrix is dynamically optimized in combination with a closed-loop feedback algorithm, and the communication quality is improved in a complex environment. Experiments show that the metasurface respectively brings 16dB, 19dB and 8dB channel gains in ideal, non-line-of-sight and real scenes, the problems that a traditional metasurface is poor in environmental adaptability and insufficient in phase precision are solved, and an innovative hardware platform is provided for 6G communication, an intelligent reflecting surface and a radar sensing system.

The invention discloses a wireless communication resource allocation method based on dynamic spectrum sensing. The method comprises the following steps: acquiring equipment node data and network environment parameters, and performing preprocessing to generate feature data; based on the preprocessed feature data and the time window, generating a spatio-temporal feature map by adopting dynamic spatio-temporal feature coding so as to capture spatio-temporal association between the devices; a hyperedge set is constructed through a hyperedge dynamic generation mechanism by using equipment position information, and network topology changes are reflected; based on the hyperedge set, the transmitting power and the channel gain, a high-order interference tensor is constructed and decomposed, and the interference relation is accurately quantified; according to the interference tensor, the number of resource blocks and the service quality requirement, generating an optimal resource allocation strategy by adopting spectral clustering and an optimization algorithm; according to the method, through the space-time attention mechanism and the high-order interference tensor modeling, the dynamic adaptability and optimization performance of resource allocation can be improved, and an efficient solution is provided for a modern wireless communication network.

The application discloses an online error calibration method for a hemispherical resonator gyro based on frequency superposition, which solves the problem that the traditional error calibration method for a hemispherical resonator gyro cannot realize online calibration of gain error, bias angle error and phase error in the same working mode. The application utilizes high-frequency cosine and sine reference signals to demodulate two-channel detection signals and extract high-frequency components in the detection signals. Subsequently, an associated model is established by using the high-frequency cosine and sine given control signals and the demodulated signals to realize online identification of the gyro error, and the identification result is applied to online calibration of the channel gain error, bias angle error and phase error, thereby enhancing the anti-interference ability of the hemispherical resonator gyro under variable temperature conditions. The application is mainly used for simultaneous online calibration of the channel gain error, bias angle error and phase error.

The invention relates to a super-surface array multi-user interference suppression method based on deep learning, and the method comprises the steps: obtaining the initial channel observation information of an environment where a super-surface array is located, and obtaining a complex channel gain matrix between a transmitting end and a plurality of receiving ends; based on initial channel observation information and a historical time sequence channel sample, inputting the initial channel observation information and the historical time sequence channel sample into an interference mapping network constructed based on a Transform structure, and predicting to obtain an inter-user interference distribution diagram at the next moment; according to the inter-user interference distribution diagram and the reflection coefficients of the metasurface units, a joint optimization objective function construction strategy network is constructed, a current channel state vector serves as input, the reflection phase of each metasurface unit is output, and a reflection coefficient moment used for minimizing an objective function is generated; feeding back indexes according to the system performance after the deployment of the reflection coefficient matrix; and dynamically configuring the metasurface unit based on the reflection coefficient matrix. According to the invention, the multi-user interference suppression effect of the metasurface array can be improved.

The invention relates to the field of communication, in particular to a method for delivering cache content of a mobile edge computing network for energy consumption optimization. For a cache-based MEC cellular network, the method reasonably utilizes user movement information, and calculates corresponding path fading, channel gain and shadow fading by utilizing future position information of a user. Determining the minimum transmission power by using the calculated channel gain and path fading, then setting a time slot, carrying out content delivery decision on data packets requested by different users, and allocating wireless communication resources; and with minimization of the total emission energy consumption of the base station as a target, modeling a cache content delivery problem into a mixed integer programming problem to carry out optimization solution so as to obtain an energy consumption minimization decision for the base station to deliver all data packets.

The invention provides an audio channel load distribution method and system. The method comprises the following steps: acquiring audio signals and audio channel load data corresponding to a plurality of audio channels; dividing the plurality of audio channels to obtain a main channel group, an auxiliary channel group and a standby channel group; for any one audio channel, the following steps are executed: obtaining an audio channel gain based on an audio channel load data audio signal, and limiting the channel gain corresponding to the audio channel to a preset gain threshold based on the audio channel gain; and acquiring main channel real-time load data, and when the main channel real-time load data exceeds the first preset load threshold value, distributing the main channel real-time load data until the main channel real-time load data is lower than the second preset load threshold value, thereby realizing balanced distribution of the audio channel load. According to the audio channel load distribution method and system provided by the invention, an audio channel overload phenomenon is avoided, and self-adaptive adjustment of audio channel gains and dynamic allocation of audio channel resources are realized.

The invention discloses an optimal concealment rate optimization method based on a time slot cognitive star-air-ground fusion network, and the method comprises the steps: firstly, enabling a satellite to select an unmanned aerial vehicle relay with the maximum channel gain as a forwarding unmanned aerial vehicle relay through the instantaneous channel state information of a link between an unmanned aerial vehicle relay and a satellite; in a second time slot, by means of a main link between the forwarding unmanned aerial vehicle relay and the main user, the forwarding unmanned aerial vehicle relay overlays the hidden message sent by the satellite to the NOMA secondary user with the message of the main user and then forwards the message downwards; a closed expression of a detection error probability, an interruption probability and an effective hiding rate of an eavesdropper is deduced, a power optimization problem is constructed and solved, and the effective hiding rate of two-hop hiding transmission is maximized by optimizing a power distribution factor. According to the method, the concealment performance of the cognitive star-sky-ground fusion network can be remarkably improved.

The invention discloses a multichannel broadband receiver, and belongs to the technical field of microwave radio frequency and electronic control, the multichannel broadband receiver comprises a multichannel down-conversion assembly, a local oscillator power component, a power interface control panel and a VPX connector, the down-conversion assembly adopts a cavity-divided integrated structure, multiple identical radio frequency links are arranged in the same cavity in parallel, and the VPX connector is connected with the local oscillator power component. Down conversion from a 2-18GHz radio frequency signal to a 1.3-2.3 GHz intermediate frequency signal is realized through two-stage frequency mixing; the power supply interface control board takes an FPGA as a core, integrates the functions of multi-path power supply conversion, driving isolation, state monitoring and the like, and realizes channel gain power failure storage and calling, BIT self-inspection, nanosecond rapid turn-off and multi-parameter real-time monitoring through software and hardware cooperation. Through collaborative innovation of the structure, circuit and control, high integration, high channel consistency, high isolation and high intelligence of the multi-channel receiver are realized, and the multi-channel receiver is suitable for the fields of high-performance radars, electronic countermeasures and the like.

The invention provides a robust hybrid beam forming method for cooperative communication of multiple low-orbit satellites, which relates to the technical field of satellite communication and comprises the following steps of: S1, constructing a joint optimization problem for joint beam forming and user scheduling; s2, the minimum channel gain of all users is maximized, when the number of satellite antennas is larger than a preset threshold value, the step S3 is executed, and otherwise, the step S5 is executed; s3, constructing a minimum signal to interference plus noise ratio maximization problem, and solving to obtain an optimal all-digital precoding matrix; s4, based on the optimal all-digital precoding matrix, constructing a digital-analog hybrid precoding matrix design problem to obtain a digital-analog hybrid precoding matrix; and S5, constructing and solving an analog pre-coding matrix design problem based on maximization of the signal leakage and noise ratio to obtain an optimal analog pre-coding matrix, and then solving an optimal digital pre-coding matrix. According to the invention, the overall performance and the service quality of the multi-low-orbit satellite communication network can be obviously enhanced.

A hidden communication method for confronting a full-duplex eavesdropper based on probability transmission in symbiotic radio comprises the following steps: constructing a system model which comprises a main transmitter Alice, a main receiver Bob, an auxiliary transmitter BD and a full-duplex eavesdropper Willie; the main transmitter Alice selectively transmits information according to a link channel state with the main receiver Bob; when the channel gain # imgabs0 # of a legal link is greater than a preset threshold value delta, the information is transmitted; otherwise, the information is not transmitted; the auxiliary transmitter BD secretly sends confidential information to the main receiver Bob through a reflection link by using the transmission behavior of the main transmitter Alice, and the full-duplex eavesdropper Willie works in a full-duplex mode and simultaneously sends artificial noise to interfere legal communication and eavesdrop. The technical problem to be solved by the invention is to provide the hidden communication method for confronting the full-duplex eavesdropper based on probability transmission in the symbiotic radio, the strong eavesdropper is confronted by using the uncertainty of link information, and the detection performance and the concealment performance of the eavesdropper are comprehensively analyzed.

The invention discloses a frequency spectrum and power distribution method for a hybrid power line / wireless MIMO (Multiple Input Multiple Output) system, which relates to the technical field of hybrid power line / wireless MIMO system communication and comprises the following steps: establishing a channel model for wireless MIMO communication and power line communication based on OFDM (Orthogonal Frequency Division Multiplexing) modulation; the method comprises the following steps: performing precoding and merging processing on wireless MIMO signals by adopting SVD (Singular Value Decomposition), so that each sub-carrier forms a plurality of parallel sub-channels; frequency spectrum allocation and power allocation are carried out through alternate optimization, and greedy frequency spectrum allocation is carried out according to parallel channel gains. According to the frequency spectrum and power distribution method for the hybrid power line / wireless MIMO system, a water injection algorithm is adopted to perform joint power distribution on wireless and PLC subcarriers, so that the power distribution is more flexible, the reliability of data transmission is improved, SVD is adopted to perform channel pre-coding, and a maximum ratio combining method is combined to combine receiving end signals, so that the reliability of data transmission is improved. And the signal quality and the system robustness are enhanced.

The invention provides a large-scale low-orbit constellation topology construction method and system based on the reliable reachable distance of an optical transceiver and a storage medium, and the method comprises the steps: 1, building an inter-satellite laser link probability evaluation model based on the capturing probability of an aiming-capturing-tracking system and the motion characteristics of satellites; 2, on the basis of the inter-satellite laser link probability evaluation model, constructing a giant satellite network topology evaluation model with inter-satellite link time average stability, satellite hop count and communication time delay as core optimization targets, and outputting a globally optimized laser link connection scheme; and 3, for a laser link connection scheme, proposing a giant constellation network topology design algorithm based on a capture probability, and constructing a constellation topology by adopting a minimum unit of a space symmetric constellation. The method has the beneficial effects that the constellation topology is constructed by adopting the minimum unit of the space symmetric constellation, so that the topological structure is stabilized, the channel gain is improved, the end-to-end delay is shortened, and the average hop count and the variance of the network are reduced.

The invention discloses a multi-channel ultra-wide-frequency-domain signal acquisition method and device. The method comprises the steps that signal sources of multiple channels are sent to the IN + end of an amplifier; the FPGA transmits the bias analog signal to the IN-end of the amplifier; a signal source and a bias analog signal are converted into differential signals, the differential signals are sent to an analog switch, and an FPGA configures a channel switching strategy and a measurement scheme of an ADC chip; the ADC performs analog-to-digital conversion on the differential signal and sends an obtained digital signal to the FPGA; the clock signal source provides a system clock and an equipment clock for the FPGA and the ADC; a multipurpose digital timing and triggering signal is connected with the analog front-end board card, and a generated synchronous sampling signal is sent to the FPGA; the FPGA synchronously acquires the voltage, current and power of alternating current and direct current in real time through the three-phase voltage and current acquisition unit; and sending the digital signal, the time node of the current sampling data and the temperature drift data to a data receiving end to complete multichannel ultra-wide frequency domain signal acquisition. The problem of measurement deviation caused by inconsistent gain of two channels of the module is solved, and the measurement precision is improved.

The invention relates to the technical field of beam forming, and discloses an RIS enhanced beam-width-adjustable beam forming method, system, medium and equipment, and the method comprises the steps: constructing an RIS-assisted ISAC system, constructing a sensing channel model in the system, and calculating the phase shift of standard beam forming; calculating the sensing gain of the potential target by combining the position of the sensing target relative to the user center based on the phase shift of the standard beam forming; reconstructing the sensing gain of the potential target by using a stationary phase method, and solving an ideal beam forming phase shift when the sensing gain of the reconstructed potential target is optimal; adjustment of the beam width and the channel gain is realized by adjusting the expression form of the ideal beam forming phase shift. According to the invention, the width of the sensing beam can be adjusted and is used for replacing resource-intensive narrow beam scanning sensing, so that the resource utilization rate is improved, the interference is reduced, and the calculation complexity is reduced.

The invention provides an underwater weak target integrated detection and positioning method using a deep sea distributed MIMO sonar, the distributed MIMO sonar is used to suppress channel fluctuation and target intensity fluctuation, and at the same time, the signal waveform of each detection node and the two-way propagation characteristic of a seabed ejection channel are combined, so that the underwater weak target integrated detection and positioning method based on the deep sea distributed MIMO sonar can be realized. A joint matching filter for simultaneously realizing signal waveform matching and channel structure matching is designed, a multipath cumulative gain is obtained on the basis of obtaining a traditional space-time processing gain, the signal-to-mix ratio and the signal-to-noise ratio are synchronously improved, and finally, a peak value fused and output by each node of the distributed MIMO sonar is used as a test statistic, so that the test accuracy is improved. And meanwhile, the peak value position is used as a target positioning result, so that integrated detection and positioning of the weak target in the deep-sea shadow area are realized. Compared with a traditional target detection method using multipath arrival feature matching, the method provided by the invention makes full use of the seabed ejection channel gain, and has better target detection and positioning effects under the conditions of low signal-to-mix ratio and low signal-to-noise ratio.

A double-lane millimeter wave vehicle networking safety transmission method, system, device and medium based on STAR-RIS, the method comprising: constructing a STAR-RIS assisted double-lane millimeter wave vehicle networking communication scene; based on the propagation characteristics of millimeter wave signals, combining the channel fading characteristics under the conditions of line-of-sight and non-line-of-sight transmission and the transmission and reflection functions of STAR-RIS, calculating the channel gain of the cascaded channel of the STAR-RIS assisted link; based on the random geometry theory, respectively calculating the probability density functions of the associated distances of the direct link, the STAR-RIS reflection link and the STAR-RIS transmission link; constructing a dynamic link association strategy supporting ternary selection; establishing a signal-to-interference-and-noise ratio model under three association modes; combining the physical layer security performance index definition, calculating the closed-form analytical expressions of the connection interruption probability and the secrecy interruption probability, and verifying the security gain of STAR-RIS; the present application has the advantages of effectively overcoming the half-space coverage blind area of the traditional reflective RIS, and improving the link connection reliability and physical layer safety transmission performance under the double-lane complex shielding environment.

This invention relates to the field of optical communication, providing a method, system, device, product, and medium for optimizing the energy efficiency of multi-access point optical communication. The method includes: calculating the link channel gain to obtain the composite channel gain; obtaining the received energy at the receiver; establishing a nonlinear received energy expression based on the received energy; constructing a battery dynamics model using the nonlinear received energy expression to obtain device energy constraints; establishing a arrival Markov matrix and a service Markov matrix based on the number of participating communication devices and their obstruction states; calculating the arrival martingale and service martingale; calculating the queue length change based on the arrival martingale and service martingale; establishing a delay default probability inequality through the queue length change to obtain an upper bound on the delay default probability; establishing communication optimization constraints; constructing a multivariate optimization equation; solving the multivariate optimization equation based on the communication optimization constraints to obtain communication optimization parameters; and optimizing the optical communication using these communication optimization parameters.

The invention discloses a channel estimation method of a time-varying channel in a time delay-Doppler domain pilot mode, which comprises the following steps of: superimposing a hybrid superimposed pilot and a data symbol in a time delay-Doppler domain, the pilot comprising a high-power center pilot and a low-power edge pilot; the signal is converted to a time domain through inverse symplectic Fourier transform and Hisenberg transform; a receiving end obtains a receiving signal through Wigner transform and Sextile Fourier transform; estimating integer time delay and Doppler taps by using a center pilot frequency, and constructing a sparse channel matrix; estimating fractional Doppler and channel gain through a sparse Bayesian learning algorithm; and detecting a data symbol based on a minimum root-mean-square error algorithm, and realizing accurate estimation of channel parameters through iterative interference elimination. According to the method, the peak-to-average power ratio and the algorithm complexity can be effectively reduced, and non-correlation channel components and cross interference are inhibited.

In various embodiments, a computer-implemented method includes: acquiring, by a computing device, measured audio data at a first location, the measured audio data including a plurality of reference sounds for a plurality of audio channels generated by a plurality of audio output devices; determining, for each audio channel of the plurality of audio channels, an audio channel gain value based on the measured audio data; and transmitting the audio channel gain values for the plurality of audio channels from the computing device to a speaker controller, the audio channel gain values being usable by the speaker controller to modify audio channels provided to the plurality of audio output devices to reproduce an audio signal.

The application discloses a kind of self-adapting array microphone cascade mixing methods, applied to microphone cascade mixing system, belong to communication technical field.Microphone cascade mixing system includes synchronization module, channel gain equalization estimation module and adaptive mixing module, synchronization module is connected with channel gain equalization estimation module by multiple channel one communication, channel gain equalization estimation module is connected with adaptive mixing module by multiple channel two communication, synchronization module is connected with adaptive mixing module by multiple channel three communication;First microphone array device is connected with synchronization module by Ch0 channel, …, Nth microphone array device is connected with synchronization module by Ch (N-1) channel.By setting synchronization module, channel gain equalization estimation module and adaptive mixing module, and using two-stage phase level synchronization processing, mixing synchronization processing, so that the application can realize volume equalization, target speech enhancement, signal quality optimization and other multiple beneficial effects.

This invention discloses a method for adjusting the active port, calculating the interruption probability, and calculating the interruption rate of shortwave communication based on a manifold antenna system in the field of wireless communication technology. The method includes: obtaining the architectural parameters of the target manifold antenna system, which include N ports uniformly distributed along a linear dimension W, each port sharing a common radio frequency link; calculating the instantaneous channel gain of each port; and selecting the port with the maximum instantaneous channel gain as the active port for shortwave communication. By introducing a manifold antenna, this invention achieves dynamic spatial adaptability within a limited area. Unlike traditional arrays with static elements, the FAS utilizes spatial diversity through real-time reconfiguration of antenna positions, eliminating the need for multiple radio frequency links. It also utilizes ionospheric reflection to establish beyond-line-of-sight connections. The FAS dynamically adjusts its active port to optimize reception from different refraction points, mitigating the inherent fading and signal attenuation of high-frequency skywave channels.

The application relates to the technical field of underwater acoustic communication, and discloses a method and system for dynamically allocating resources of an underwater voice communication system. The method comprises the following steps: setting a multi-user priority strategy according to a formation modular grouping; adopting a hybrid access mechanism of fusion of time division multiple access and carrier sense multiple access / collision avoidance, dividing communication channels into inter-group time slots and intra-group time slots, and competing for access to idle sub-carrier clusters in the time slots through a CSMA / CA mechanism; predicting a future state of an underwater acoustic channel; based on the predicted future state, adaptively switching a modulation and coding scheme according to a preset signal-to-noise ratio threshold; distributing sub-carrier bands to users with the largest channel gain based on a channel gain matrix; and combining the multi-user priority strategy, the hybrid access mechanism and the modulation and coding scheme to jointly optimize and distribute sub-carriers, bit loading and transmission power. Through dynamic resource allocation and adaptive transmission optimization, the application effectively improves the resource utilization rate and transmission quality of underwater voice communication.

The present invention discloses an OSIC detection method for an underwater optical Massive MIMO communication system with misaligned transmission and reception. After estimating the gain of each sub-channel using the LS channel estimation algorithm, the offset direction of the transceiver can be determined based on the magnitude of each DC gain in the channel gain matrix. The detection column order and the order within the column are then determined based on the offset direction, and interference elimination is performed to complete the detection of each signal. The present invention sorts according to the offset direction, preferentially detecting signals without interference, and then detecting signals with interference, greatly reducing the error propagation caused by the sorting, making the subsequent stage more accurate in subtracting the detected signal, and making the remaining signal used in the subsequent stage have less interference, thereby improving the bit error rate performance, so as to solve the problem of increased bit error rate of the UWOC system caused by misalignment of the transceiver and offset and diffusion of the imaging spot in the underwater imaging optical Massive MIMO communication system.

A method is disclosed of selecting users for multi user multiple-input multiple-output (MU-MIMO) communication from an initial set of potential users. The method comprises repeating the following steps in successive iterations until a stopping criterion is met: determining a channel correlation metric for each user in the set of potential users, reducing the set of potential users by exclusion of a user based on the channel correlation metric, and calculating a performance metric of the set of potential users. The method also comprises selecting users corresponding to one of the sets of potential users, wherein the selection is based on a comparison of the calculated performance metrics of the sets of potential users. The channel correlation metric for a user may comprise one or more of: a channel filter norm for the user, a channel norm for the user, a channel gain for the user, pair-wise correlations between the user and one or more other users of the set of potential users, and a channel eigenvalue for the user. The performance metric may comprise one or more of: a sum-rate, a per-user-rate, an average error rate, a maximum error rate, a per-user error rate, and a sum-correlation. Corresponding apparatus, network node and computer program product are also disclosed.

The application discloses a satellite large-scale MIMO beam structure downlink precoding method and uplink detection method. In the beam base channel model established by the application, the scaling direction cosine is uniformly sampled and quantized, and the uplink / downlink beam matrix is constructed, the space domain channel vector is expressed as the product of the equivalent uplink / downlink channel gain, the uplink / downlink beam matrix and the diffusion vector. Based on the downlink / uplink beam base channel model, the statistical channel information is used to design the downlink precoder / uplink detector under the beam structure, and the high-dimensional space domain precoder / detector design is converted into the low-dimensional beam domain precoder / detector design. Using the designed precoder and detector, low-complexity downlink precoding transmission processing and uplink receiving processing are respectively carried out. The application fully utilizes the sparse characteristics of the satellite channel, guarantees the uplink and downlink ergodic and rate performance of the satellite large-scale MIMO system, and effectively reduces the design and implementation complexity of the precoder and the detector.

The invention relates to a resource allocation method and device for a multi-user orthogonal frequency division multiplexing system. The method comprises: sending a channel assessment message carrying a pre-configured channel assessment frame to a plurality of user nodes, the channel assessment message being used for indicating each user node to perform channel assessment according to the received channel assessment frame, and feeding back an average channel gain and an average signal-to-noise ratio obtained by assessment to a main node, the pre-configured channel evaluation frame is obtained based on configuration of a preset orthogonal frequency division multiplexing symbol sequence; receiving an average channel gain and an average signal-to-noise ratio fed back by each user node; and for each user node, determining a target bit number and target sending power allocated to the user node according to the average channel gain and the average signal-to-noise ratio fed back by the user node, generating a channel resource configuration frame according to the target bit number and the target sending power, and sending the channel resource configuration frame to the user node. By adopting the method, the calculation complexity of resource allocation can be reduced.

The invention discloses an active mode demultiplexing module which comprises a mode converter, two optical circulators and a bidirectional semiconductor optical amplifier. The mode converter is used for converting a high-order mode into a fundamental mode to complete primary mode demultiplexing, fundamental mode signals after primary demultiplexing are injected into the bidirectional semiconductor optical amplifier through the two optical circulators from the positive direction and the negative direction respectively, and the signals after being shaped by the bidirectional semiconductor optical amplifier are output by the corresponding optical circulators. A bidirectional symmetrical injection structure is formed, different propagation is beneficial to separation of different signals, and mutual interference, namely mode crosstalk, between forward and reverse signals can be effectively reduced, so that a mode demultiplexing function is better completed, and an output signal has higher signal quality than a primary demultiplexing signal. Besides, by optimizing and adjusting the driving current of the bidirectional semiconductor optical amplifier or an auxiliary optical pumping mode, not only can the gain of the mode channel be dynamically adjusted, but also the power balance of the mode channel and the demultiplexing of a high extinction ratio mode can be realized; the method is especially suitable for receiving few-mode signals in a mode division multiplexing (MDM) optical transmission system and constructing optical switching nodes in a multi-dimensional multiplexing optical network.

The invention provides a near-field multi-user joint visual area detection and channel estimation method and device, and is applied to the technical field of wireless communication. The method comprises the following steps: acquiring an observation signal, wherein the observation signal is a pilot signal sent by a near-field user; the hidden variable parameters, the grid parameters and the visible area matrix of the near-field user are iteratively updated according to the observation signals, the hidden variable parameters comprise channel gain and noise precision, and the grid parameters are two-dimensional polar domain dynamic grids and are used for describing distribution characteristics of angles and distances; the visible area matrix is used for quantitatively representing a visible relationship between the grid unit and the antenna sub-array; wherein the updating basis of the hidden variable parameters comprises the newest generated grid parameters and the newest generated visible area matrix, and the updating basis of the grid parameters comprises the newest generated hidden variable parameters and the newest generated visible area matrix. The updating basis of the visual area matrix comprises a newly generated hidden variable parameter and a newly generated grid parameter.

The invention provides a channel gain map reconstruction method based on a k-nearest neighbor refined neural network, relates to the technical field of wireless communication, and has the technical key points that the invention provides a two-stage CGM reconstruction framework under a sparse regular grid sampling condition, and in the stage 2, local learning is carried out during query to refine prediction, so that explicit decoupling and robust extrapolation are realized. K nearest neighbors are selected from a total sample by adopting a global k nearest neighbor thought which is not constrained by a clustering boundary, spatial continuity is preferentially utilized, and k nearest neighbors in a cluster which can be used as a contrast are selected only in the same cluster. The whole process does not depend on LoS / NLoS labels or high-cost environment prior, the CGM can be reconstructed only by regular grid sampling measurement, and high-precision benefits are kept under different sampling interval values d and k. On the premise of not increasing expensive measurement and label cost, the MSE of CGM reconstruction is obviously reduced.