12 results about "Asynchronous interference" patented technology

The invention discloses a downlink precoding method and device, electronic equipment, a storage medium and a program, and is applied to a sending end, the method comprises the following steps: obtaining communication configuration information, and determining an average interference power leakage coefficient of different users on scheduled subcarriers according to the communication configuration information; determining an average channel power and an array response vector of each user based on the communication configuration information; according to the average interference power leakage coefficient, the average channel power and the array response vector, determining a downlink precoding vector of each user according to an average signal leakage noise ratio maximization criterion; and obtaining a downlink transmission signal of each user, and performing weighting processing on the transmission signal of each downlink user according to the downlink precoding vector of each user, thereby obtaining a downlink transmission signal corresponding to each downlink transmission beam. According to the embodiment of the invention, the problem of asynchronous interference among different users in the mobile phone direct connection satellite communication system can be solved, and the downlink transmission performance of the multi-beam satellite mobile communication system can be improved.

The invention relates to a robust transmitter design method for a large-scale sensor network in a complex environment. The robust transmitter design method is applied to a sensor node transmitter with limited crystal oscillator performance. Comprising the following steps: constructing an uplink asynchronous received signal model of a base station and N sensor terminals, performing maximum ratio combination detection on a received signal, and decomposing the received signal into a target signal, effective noise and multi-symbol asynchronous interference; respectively calculating target signals, effective noise and asynchronous interference energy to construct a signal to interference plus noise ratio model; constructing a codebook optimization problem by taking maximization of a minimum signal to interference plus noise ratio as a target and taking codeword power normalization as a constraint; and optimizing a multi-user codebook in a random asynchronous interference scene based on a DDPG reinforcement learning framework to generate an optimal codebook which meets power normalization constraint and maximizes the minimum SINR, and the optimal codebook is used for symbol coding mapping of a transmitter. The method is adaptive to hardware characteristics of the low-cost sensor, random asynchronous interference introduced by time-varying crystal oscillator offset is effectively resisted, and the reliability of concurrent communication of the low-cost sensor is improved.

The present invention provides a radar co-frequency asynchronous interference suppression method based on slow-time interpolation, the method comprising: extracting sample data sets X of the same range gate Nr received by the radar in the slow-time dimension. Nr_i The sample data group X Nr_i The process involves filtering to identify pulse period sequence group K containing interference signals. j And the pulse period sequence number group K that does not contain interference signals s The interference signal is restored; slow-time dimension sample interpolation is performed to obtain the processed signal X'. Nr_Kj Improve the performance of the radar.

The invention relates to the field of communication technology and tunnel engineering crossing technology, and discloses a tunnel-embedded multi-source global coverage repeater system and method, the system comprises a tunnel-embedded deployment structure and repeater modules, the repeater modules are embedded into a tunnel side wall through the tunnel-embedded deployment structure, and multiple modules form a cascade network through cascade interfaces; the repeater module comprises an unvarnished transmission layer, a collaboration layer and an algorithm layer. The method corresponds to the system. According to the method, excavation-free transformation is achieved through tunnel-embedded deployment, construction is simplified, and deployment convenience is improved; the unvarnished transmission layer amplifies a multi-source signal through radio frequency direct connection, and prevents asynchronous interference in combination with time domain synchronization to guarantee signal integrity; the collaborative layer realizes multi-source on-demand collaborative coverage through frequency band identification, dynamic adjustment of coverage weight and transmitting power and signal coupling isolation combination; the algorithm layer constructs a tunnel topology model, predicts the coverage intensity, automatically optimizes the power, eliminates blind areas and avoids redundancy, thereby providing support for tunnel multi-source global high-quality coverage, and meeting intelligent traffic demands.

The invention discloses a multi-user detection method and device based on an expansion factor graph and a graph attention network, and the method comprises the steps: carrying out the multi-time oversampling of an asynchronous uplink signal of a receiving end, obtaining a plurality of sampling observations in each symbol period, and constructing the expansion factor graph based on the sampling observations; performing feature extraction on the oversampling receiving signal, and taking a real part and an imaginary part as deep neural network input to obtain node features; and a graph attention network is introduced into the expansion factor graph to carry out information interaction and model training, and a model obtained by training is utilized to judge signals received by each user, so that multi-user joint detection is realized. According to the method, the oversampling signal is modeled into the expansion factor graph structure, and the graph attention mechanism is introduced, so that effective detection of the multi-user signal in the asynchronous SCMA system is realized, and the problems of high multi-user detection complexity and insufficient asynchronous interference resistance in an uplink asynchronous SCMA scene are solved.

The application relates to a kind of air-based asynchronous communication multi-user transmitter design methods, belong to wireless communication technical field, method includes: constructing air-based uplink asynchronous communication system model, base station received signal is characterized as each user time delay and channel weighted codebook coded pulse shaping signal superposition;Received signal is decomposed into target signal, multi-symbol asynchronous interference and effective noise, the signal-to-noise ratio of each user is determined;With the minimum signal-to-noise ratio in all users as the target, with code word power normalization as the constraint condition, the codebook optimization problem of transmitting signal is constructed;Meta-learning algorithm is used to construct task space with time delay information for offline pre-training to obtain meta-model;In the online stage, the current time delay is input, and the adaptive codebook is quickly generated through the meta-model, and the codebook is used for the transmitter to encode the sending symbol to generate the transmitting signal.The application improves the signal-to-noise ratio of multi-user received signal, thereby realizing the reliability of wide-area asynchronous communication of unmanned aerial vehicle.

This invention proposes a method and apparatus for reducing false alarms caused by asynchronous interference in an airborne collision avoidance system. Based on the principle of not affecting the normal function of the airborne collision avoidance system and meeting standard requirements, this invention filters out asynchronous interference signals to a certain extent by performing "intensity-distance" correlation judgment on the response signals received by the airborne collision avoidance system and adding a false target confirmation process within the minimum protection distance, thereby reducing the probability of asynchronous interference signals forming false targets and false alarms.

The application discloses an air traffic control radar narrow pulse interference pulse pressure pre-post combined suppression method, which comprises the following steps: S1, saturation detection and noise accumulation are performed on original data; S2, a bearing-clutter intensity map is established, and clutter cancellation is performed; S3, anti-narrow pulse processing is performed on the pulse cancellation data and original I and Q data in the time domain; S4, step interference detection is performed on the cancellation data, and suspected interference units are marked; S5, suspected interference point confidence evaluation is performed; the confidence of the point in the suspected interference unit window is calculated, the confidence calculation is based on the eigenvalue of the point, and if the calculated confidence is lower than a preset value, the point is discarded. The method effectively solves the influence of clutter on interference detection, performs fine interference detection and suppression according to the characteristics of narrow pulse interference and asynchronous interference, and calculates the confidence of suspected interference points after point condensation, so that the influence of narrow pulse interference on point formation and track association is reduced.

The invention relates to a method for designing a multi-user transmitter for space-based asynchronous communication, which belongs to the technical field of wireless communication, and comprises the following steps of: constructing a space-based uplink asynchronous communication system model, and representing a base station receiving signal as superposition of codebook coding pulse shaping signals of each user after time delay and channel weighting; decomposing the received signal into a target signal, multi-symbol asynchronous interference and effective noise, and determining a signal to interference plus noise ratio of each user; constructing a codebook optimization problem of a transmitted signal by taking maximization of a minimum signal to interference plus noise ratio in all users as a target and taking codeword power normalization as a constraint condition; a meta-learning algorithm is adopted to construct a task space based on the time delay information for offline pre-training to obtain a meta-model; in the online stage, the current time delay is used as input, an adaptive codebook is quickly generated through the meta-model, and the codebook is used for a transmitter to encode a sending symbol so as to generate a sending signal. According to the invention, the signal to interference plus noise ratio of multi-user received signals is improved, so that the reliability of wide-area asynchronous communication of the unmanned aerial vehicle is realized.

This application relates to a method for resisting co-frequency asynchronous interference in FMCW traffic radar. It utilizes a composite modulation scheme combining inter-frame frequency hopping, inter-frame pulse position pseudo-random code modulation, and inter-pulse phase pseudo-random code modulation to achieve anti-interference. With the increasing number of traffic radars, including vehicle-mounted and roadside radars, even though multiple radars operate simultaneously in the same area, this co-frequency asynchronous method ensures stable and reliable operation of each radar, accurately acquiring target distance, speed, and angle information, providing accurate data for intelligent driving or traffic management and monitoring.

The invention discloses a radar target detection method based on a computer vision dynamic template, and the method comprises the steps: radar video sampling and preprocessing, radar image corrosion based on constant false alarm, radar image smoothing based on gradient information, and finally employing adaptive double-threshold Canny edge detection, and extracting target position and amplitude information based on a detected target. And target detection is completed. According to the scheme, edge extraction is completed under the A display condition, a constant false alarm corrosion algorithm is provided, and weak (sea clutter) and discontinuous (asynchronous interference) targets are inhibited; for radar video echo features, a dynamic template image smoothing threshold and a prior statistical threshold are provided respectively, and the current situation that Canny edge detection Gaussian image smoothing affects edge precision and threshold selection depends on artificial experience dynamic adjustment is solved. And finally, completing edge coordinate transformation, calculating a target center position (centroid point), performing target size and amplitude feature statistics, and realizing target visual feature extraction.

The disclosure relates to a communication technique that merges Internet of things (IoT) technology with a 5th generation (5G) communication system for supporting higher data transmission rates than 4th generation (4G) systems, and a system for same. A method and a device for specifying a cell generating an asynchronous interference are provided. The method includes obtaining base station related information including a location for each base station and received signal strength indication (RSSI) information for each symbol from a base station, identifying whether a cell related to the base station is a cell in which asynchronous interference occurs between cells based on the RSSI information for each symbol, grouping cells in which the asynchronous interference between cells occurs based on the location for each of the base station, determining a type of asynchronous interference between cells, and determining a cell that generates the asynchronous interference between cells.