11 results about "Path loss exponent" patented technology

The invention discloses a joint estimation indoor positioning method, a joint estimation indoor positioning system, a medium and equipment, and relates to the technical field of indoor positioning, and the joint estimation indoor positioning method comprises the steps that each anchor node sends a signal to a neighbor anchor node and collects RSSI data, the collected data is fitted, and the path loss index of each anchor node is estimated; performing k-means clustering analysis on the path loss index, and taking the mass center with the most indexes as a final path loss index estimation value; constructing a positioning problem by using a maximum likelihood estimation method and Huber loss, and converting the positioning problem into a joint optimization problem of hybrid semi-definite second-order cone programming; and dynamically updating a Gaussian mixture noise parameter through an EM algorithm, synchronously optimizing the position of a target node and the transmitting power of an anchor node in each iteration, and outputting a final positioning result. According to the method, the target node is positioned under the condition that malicious anchor nodes and Gaussian mixed noise exist, and the accuracy and efficiency of positioning are improved.

The invention discloses a region-centered unmanned aerial vehicle coverage rate analysis method. The method comprises the following steps: constructing a region-centered unmanned aerial vehicle cooperative transmission model; fractional power control is carried out on the service unmanned aerial vehicle and the interference unmanned aerial vehicle; calculating the signal-to-interference ratio of the typical user based on the transmitting power of the service unmanned aerial vehicle and the interference unmanned aerial vehicle; based on the stochastic geometry theory, the coverage probability of typical users is obtained through service distance distribution, signal power distribution and interference distribution in combination with a Cauchy-Schwarz inequality and Gamma distribution approximation; the unmanned aerial vehicle density, the power control coefficient, the path loss index and the Nakagami fading parameter are set, the influence of the number of different service unmanned aerial vehicles, the power control coefficient and the channel condition on the coverage probability is analyzed, and simulation verification is carried out. According to the method, the technical problem of how to suppress the network interference of the unmanned aerial vehicle through power control in a complex interference scene is solved, and the network coverage rate of the unmanned aerial vehicle is calculated.

The invention discloses a satellite-ground convergence network uplink secure transmission method based on a satellite selection strategy. The method comprises the following steps: constructing a double-layer satellite-ground convergence network uplink communication model; calculating models of the upper bound and the lower bound of the average secrecy rate of passing of the ground sensor terminal and the service satellite are determined based on an uplink communication model of the double-layer satellite-ground fusion network, and the average secrecy rate of communication of the ground sensor terminal and the optimal service satellite is simulated through Monte Carlo simulation; under the communication conditions of different path loss indexes, different eavesdropping satellite densities and different height ratios of the eavesdropping satellites to the service satellites, the eavesdropping satellites are obtained; the lower bound of the average secrecy rate, obtained through the calculation model, of passing of the ground sensor terminal and the service satellite is compared with the secrecy rate of communication of the analogue simulation ground sensor terminal and the optimal service satellite, and communication satellite selection strategies under different communication conditions are obtained; and selecting a communication satellite for information transmission according to the communication satellite selection strategy.

The application discloses a kind of joint estimation indoor positioning method, system, medium and equipment, it is related to indoor positioning technical field, including each anchor node sends signal to neighbor anchor node and collects RSSI data, fitting to collection data, estimate the path loss index of each anchor node;It is carried out k-means clustering analysis, and the most centroid of index is taken as the final path loss index estimation value;Maximum likelihood estimation method and Huber loss are used to build positioning problem, and the positioning problem is converted into the joint optimization problem of mixed semi-definite quadratic cone programming;Through EM algorithm, mixed gaussian noise parameters are dynamically updated, the position of target node and anchor node transmission power are optimized synchronously each time iteration, and the final positioning result is output.The application realizes the positioning of target node in the case where there is malicious anchor node and gaussian mixture noise, improves the accuracy and efficiency of positioning.

The application provides a Bluetooth device positioning method and device applied to a Bluetooth beacon, and an electronic device, and relates to the technical field of positioning. The method comprises the following steps: determining a plurality of target Bluetooth devices in the transmission range of the Bluetooth beacon, each target Bluetooth device being connected to a Bluetooth device to be positioned outside the transmission range through Bluetooth; acquiring the position, transmission power, path loss index and received signal strength indication (RSSI) on the Bluetooth device to be positioned when the Bluetooth signal emitted by any target Bluetooth device is received by the Bluetooth device to be positioned; obtaining the distance between the target Bluetooth device and the Bluetooth device to be positioned as the device distance corresponding to the target Bluetooth device according to the parameters of each target Bluetooth device acquired above; and obtaining the position of the Bluetooth device to be positioned according to the positions of the plurality of target Bluetooth devices, the plurality of device distances and the position of the target Bluetooth beacon. The application can reduce the cost of device deployment in indoor positioning, and reduce the cost, complexity and workload of device maintenance.

The invention discloses a channel allocation method based on synchronization ages and electronic equipment, and the method comprises the steps: obtaining the current synchronization age corresponding to each piece of transmitting equipment for any time slot, and if the current synchronization age is greater than or equal to a network global age threshold value of an Internet of Things communication system, sending the transmitting equipment to a server; determining that the corresponding transmitting device is allowed to compete for a wireless channel in the time slot and the transmitting device tries to send a data packet to the corresponding receiving device, the network global age threshold being determined based on network parameters of the Internet of Things communication system; network parameters comprise density, a distance between a transmitting device and a receiving device, a path loss index of a channel, an updating probability of the transmitting device, a signal interference noise ratio threshold value and a preset age threshold value, a channel access opportunity can be preferentially guided to a device with higher synchronization age, unnecessary low-age information transmission collision is reduced from the aspect of mechanism, and the reliability of the system is improved. And the whole information synchronization timeliness of the network is systematically optimized.

The application discloses a surface wave wireless channel modeling optimization method based on a sending end coupling distance, which comprises the following steps: setting a sending end, a receiving end and metal pipes with different diameters; a transceiving antenna is coupled to the metal pipes with different diameters in a wireless mode; the height of the receiving end is fixed, the height of the sending end and the distance between the sending end and the receiving end are changed, the measurement data of the wireless channel of the receiving end at different sending end heights are collected, path loss values are extracted, and a path loss model with the influence of the sending end coupling distance is constructed; the path loss model is subjected to parameter fitting by using a least square method, the path loss index is modeled, the correction values of the parameters in the path loss model are obtained, and a final path loss model is obtained after correction; and the distance between the sending end and the receiving end and the sending end coupling distance are inputted, so that the channel path loss value of the transceiving end can be obtained. The application can effectively optimize the performance of a wireless communication system in an indoor environment of an industrial internet of things.

The invention provides a wireless access point positioning method based on received signal strength. The wireless access point positioning method comprises the steps that S1, RSS original data of a target wireless access point are collected through receivers, and corresponding RSS observation values are obtained through processing according to the RSS original data; s2, constructing a to-be-estimated parameter vector containing a target position coordinate, a path loss index and reference power of the target wireless access point; s3, based on a path loss model, establishing a nonlinear model function between the RSS observed value and the to-be-estimated parameter vector; and S4, constructing a least square problem according to the nonlinear model function, and carrying out iterative solution by adopting a Gaussian-Newton method to obtain a least square estimated value of the to-be-estimated parameter vector as a target position coordinate of the target wireless access point. The method has the advantages that the method can automatically adapt to different indoor positioning scenes, tedious parameter calibration in advance is not needed, and high positioning precision and calculation efficiency can be kept.

The application relates to the technical field of radio frequency identification positioning optimization, and discloses a positioning optimization method and system based on distributed long-distance wireless radio frequency identification, which comprises the following steps: acquiring a radio frequency signal, carrying out data processing and feature extraction, and obtaining a multipath feature vector; matching the multipath feature vector with a feature template, extracting a path loss index, adopting a logarithmic distance path loss model, and calculating a theoretical device distance; carrying out path separation on the radio frequency signal, obtaining a path time delay interval of each path, determining a signal angle range according to the path time delay interval and the theoretical device distance, generating signal processing parameters according to environmental noise data; carrying out distance calculation on the radio frequency signal according to the signal angle range and the signal processing parameters, obtaining an actual device distance, and calculating a transmitting end device coordinate according to the actual device distance and a receiving end device coordinate. The application realizes accurate and efficient device positioning in a complex environment by suppressing multipath interference and dynamically compensating for the environment.

The invention provides an electric power material location positioning method, device and system, and a storage medium, and is applied to the technical field of electric power material management. The method comprises the following steps: acquiring environment characteristic data of an area where the portable positioning equipment is located; acquiring a signal attribute corresponding to a wireless signal from a terminal transmitting device arranged at the target electric power material, wherein the signal attribute comprises a received signal strength value; predicting a path loss index through a pre-trained path loss index prediction model based on the environment characteristic data and the received signal strength value to obtain a dynamic path loss index matched with the current environment; and according to the dynamic path loss index and the received signal strength value, the relative distance between the target electric power material and the portable positioning equipment is determined, so that the positioning efficiency and accuracy are improved, and the personnel safety risk is reduced.

The application discloses a kind of indoor high-frequency band wireless body area network off-body channel modeling method.For the influence caused by the relative angle between the sending end human body and the receiving end human body to the path loss of off-body channel, the application first analyzes the influence of the relative angle between body-to-body on channel characteristics using wireless propagation theory;Then, using the path loss exponent related to the relative angle between body-to-body, the floating intercept, and the path loss caused by the change of the relative angle between body-to-body, a new path loss model is established;Finally, the least squares method is used to fit and determine the related parameters of the established model, so that it can more accurately represent the wireless propagation characteristics of the actual communication scenario.Compared with the traditional logarithmic path loss model, the application can be closer to the actual measurement results due to the consideration of the influence of the relative angle between body-to-body.