657results about "Scatter propogation systems" patented technology

This application discloses an information transmission method and apparatus, a first device, and a second device, which belongs to the field of communication technologies. The information transmission method in embodiments of this application includes: sending, by a first device, frequency offset indication information to a second device, where the frequency offset indication information is used for controlling a frequency offset generated during modulation of a carrier signal, and the frequency offset is an offset relative to a central frequency of the carrier signal; and receiving, by the first device, data transmitted by the second device, where the data is transmitted through a backscatter signal sent by the second device to the first device, and the backscatter signal is a signal obtained after the second device modulates the carrier signal based on the frequency offset indication information.

Systems, methods, apparatuses, and computer program products for mode switching schemes for reconfigurable intelligent surface (RIS) assisted backscatter communications. The method may include connecting with a network node for communication, receiving, from the network node, an indication of activation of backscattering, receiving a backscatter signal together with a signal sent by the network node, and demodulating the backscatter signal and the signal sent by the network node, the backscatter signal including backscatter data.

Certain aspects of the present disclosure provide techniques for wireless communication by a user equipment. The techniques include receiving, from a backscatter device, first backscatter data during one or more network entity downlink slots; receiving, from the backscatter device, during a network entity uplink slot immediately following the one or more network entity downlink slots, second backscatter data; and combining, at the user equipment, the first backscatter data and the second backscatter data to generate a backscatter data package.

The present disclosure discloses a geometry-based stochastic channel modeling method oriented to a wireless communication in an underground mine. The geometry-based stochastic channel modeling method generates basic parameters such as an environment and antennas; generates a three-dimensional time-varying twin-cluster channel environment, that is, a number, a distance and an angle distribution of the clusters, and the like; derives channel parameters such as a position distribution of scatterers, and a power distribution of the scatterers in the clusters; introduces a roughness of a wall and characterizes an influence caused by the rough wall from two aspects of a phase variation and an energy attenuation according to angle parameters, calculates a time-varying channel impulse response and a channel matrix, and implements a simulation channel model and analyzes a statistical characteristic of a channel. The present disclosure adopts a geometry-based stochastic channel modeling method to establish an underground mine channel model, which considers a unique channel characteristic of the rough wall and has a relatively high accuracy, a moderate complexity, and a better universality, and the statistical characteristic of the simulation has a reference value for the design for the communication system in the underground mine.

A novel scatterer density-based predictive channel modeling method includes: obtaining channel data with different scenarios scatterer densities through a channel measurement or a simulation; obtaining corresponding channel statistical characteristic parameters through a data preprocessing based on the channel data; constructing a graph dataset by taking scatterer density in different scenarios as main characteristics to enhance a space-time correlation of data; dividing the graph dataset according to a certain proportion, and then using a graph attention network and a gated recurrent unit network to extract correlated channel space-time characteristics and implementing a cross scenario channel prediction. The method can capture channel variations in different scenarios, and obtain channel characteristics under different scatterer densities through high space-time correlated channel characteristics, and has good performance in channel prediction based on scenario.

Disclosed are systems and techniques for wireless communications. For example, a first network device can transmit, to second network device(s), a first information signal including information indicating a frequency for a backscattered signal. The first network device can transmit, to a third network device, a second information signal including information indicating a frequency shift for shifting a reference signal to produce the backscattered signal. The first network device can transmit the reference signal to the third network device. The first network device can select, based on channel reports received from the second network device(s), the energy harvesting waveform and at least one second network device for providing the energy harvesting waveform to the third network device. The first network device can transmit, to the at least one second network device, a scheduling signal including scheduling instructions to transmit the energy harvesting waveform to the third network device.

The invention discloses a LoRa-based parallel backscatter communication method and system. The method comprises the following steps: transmitting a single-tone radio frequency source signal as a signal excitation source; designing a backscattering label, and performing backscattering modulation processing on the environmental perception data in combination with the signal excitation source to obtain a modulated standard LoRa data packet; and the receiver presets the center frequency of a communication link, and performs frequency band distinguishing and demodulation processing on the modulated standard LoRa data packet to complete parallel backscatter communication of the LoRa data. According to the invention, while a parallel backscattering LoRa communication system compatible with commercial LoRa equipment is realized, the throughput of the system is improved, and frequency division multiple access parallel transmission is realized. The LoRa-based parallel backscatter communication method and system can be widely applied to the technical field of parallel backscatter communication.

Systems and techniques are provided for wireless communications. A process can include receiving first configuration information associated with transmission of carrier wave (CW) signals to an ambient Internet of Things (AIoT) device, wherein the first configuration information is indicative of a plurality of candidate frequencies. The process can include determining, based on second configuration information, that the network entity is a valid source for a current CW transmission occasion. The process can include transmitting, to the AIoT device, a first CW signal using a selected frequency of the plurality of candidate frequencies, wherein a transmission power for the first CW signal is based on the second configuration information.

The invention belongs to the technical field of maritime wireless communication. The invention provides an evaporation waveguide and scatter communication mode discrimination method based on measured data. According to the embodiment of the invention, the method comprises the steps: setting a threshold value of a difference between a troposphere scattering path loss simulation value of a troposphere propagation prediction model and an actual measurement path loss average value according to the parameters, such as a communication distance, a working frequency, a transmitting antenna gain and a receiving antenna gain; and according to an evaporation waveguide and troposphere scatter communication mode discrimination criterion, a current offshore beyond visual range communication mode is accurately discriminated. According to the method, the maritime beyond-visual-range communication system can fully utilize the evaporation waveguide to reduce the power consumption of the communication system or improve the communication rate, and key technical support can be provided for performance improvement of the maritime beyond-visual-range communication system.

The invention discloses a non-orthogonal multiple access backscatter communication method, which belongs to the field of communication technology. The non-orthogonal multiple access backscatter communication method comprises: transmitting an electromagnetic wave signal generated by a transmitter to a backscatter tag; the backscatter tag adjusts and spreads the electromagnetic wave signal to obtain a NOMA backscatter signal; the NOMA backscatter signal amplifies the signal through a tunnel diode circuit; the amplified signal is reflected by the backscatter tag and reaches a receiver; the non-orthogonal multiple access backscatter communication method, based on a demodulation scheme of a tunnel diode, increases the power difference between multiple users, thereby improving the demodulation performance, and secondly, through an improved minimum mean square error continuous interference cancellation (MMSE-SIC) algorithm, a special frame design is used to solve the carrier frequency offset (CFO) problem caused by the use of a low-precision oscillator.

The invention relates to the technical field of wireless communication, and discloses a millimeter wave backscatter communication positioning and identification system for multiple tags, which comprises a Chirp signal sending module used for generating and transmitting continuous Chirp signals and receiving signals reflected by customized backscatter tags; and the received signal processing module is used for carrying out demodulation and frequency analysis on the received radar echo signal, determining the distance of the target backscattering tag by measuring the frequency offset of the intermediate frequency signal, and determining the azimuth of the tag through the antenna array of the receiving module. The identity label of the backscattering label is extracted by analyzing the signal intensity; the customized backscattering label is used for adjusting the intensity of the signal reflected back to the radar by changing the reflection state of the backscattering label so as to transmit the identity label of the backscattering label; and the DSSS coding module is used for coding the identity label of the backscattering label so as to increase the signal bandwidth and reduce the signal interference between the labels. According to the method, the customized backscattering tag is matched with the FMCW radar, so that positioning and identification of multiple tags are realized, and the method has a wide application prospect.

Method, apparatus, and device for communicating with an extended range. The apparatus is a network apparatus communicating with an ambient internet of things device having an energy storage and capability to transmitting data by backscattering a radio transmission. The apparatus detects that the device has failed to transfer data by backscattering and responsively sends to the device a first radio transmission having instructions to decrease a radio reflection coefficient to increase wireless energy harvesting. The device decreases the radio reflection coefficient accordingly. The device detects sufficient wireless charging of its energy storage with the decreased radio reflection coefficient and increases the radio reflection coefficient accordingly.

Certain aspects of the present disclosure provide techniques for radio frequency identification (RFID) tag singulation. Certain aspects provide a method for wireless communication by a first receiver, such as a passive RFID tag. The method generally includes receiving, from a transmitter, a first signal initiating a first inventory round and in response to receiving the first signal, backscattering a second signal to the transmitter, wherein the second signal is backscattered using resources specific to the first receiver.

The invention provides a hidden backscatter communication method based on multicarrier randomized continuous waves. The method comprises the following steps: acquiring multicarrier randomized continuous wave signal characteristic parameters, backscatter signal characteristic parameters and channel parameters between a transceiver and a listener and between the transceiver and each user; according to the characteristic parameters of the multicarrier randomized continuous wave signal and channel parameters between the transceiver and the listener and between the transceiver and each user, determining relative entropy between probability density functions of the listener receiving signal when the user generates a backscattering signal and when the user does not generate the backscattering signal; determining the total reachable rate between the transceiver and all users according to the multicarrier randomized continuous wave signal characteristic parameters, the backscattering signal characteristic parameters and the channel parameters; and maximizing the total reachable rate through a target optimization algorithm by taking the condition that the relative entropy meets the concealment condition as the constraint, and obtaining the optimized statistical characteristic parameters of the multicarrier randomized continuous waves. According to the invention, hidden backscatter communication can be realized.

The invention provides a common-antenna zero-power-consumption Internet of Things terminal energy management system based on radio frequency energy taking, which comprises a radio frequency antenna, a radio frequency energy taking module, a rectification energy storage module, a low-frequency wake-up module, a backscatter communication module and an MCU control unit, in the MCU control unit, a single-chip microcomputer controls the on-off of a power supply of a sensor through a sensor power supply control pin; a power supply of the sensor and a radio frequency switch of the backscatter communication module are switched on only in a wake-up state, and only power supply to a wake-up pin is reserved in the single chip microcomputer; through a three-layer architecture of energy capture, energy control and energy application, the terminal equipment is completely separated from battery dependence. The system constructs a closed-loop energy management system for energy collection, storage, scheduling and dormancy, the scheme is suitable for the field of passive Internet of Things with strict requirements on power consumption, cost and deployment flexibility, and a feasible solution is provided for an Internet of Things terminal.

The invention belongs to the technical field of metamaterial sensors, and particularly relates to a metamaterial multi-parameter sensor for a complex environment, which comprises a dielectric substrate, a temperature sensor, a pressure sensor and a strain sensor, and is characterized in that the dielectric substrate is made of high-temperature co-fired alumina ceramic; the temperature sensor is arranged at the left end of the dielectric substrate; the pressure sensor is arranged in the middle of the medium substrate; and the strain sensor is arranged at the right end of the dielectric substrate and comprises a metal sheet structure capable of generating relative displacement. According to the invention, long-distance signal monitoring is realized by adopting a microwave scattering technology, and the problem that a traditional wired sensing transmission line is damaged at a high temperature is solved; the high-temperature-resistant aluminum oxide HTCC ceramic is used as the dielectric substrate, temperature measurement within the range of 25 DEG C to 1200 DEG C, pressure within the range of 0 kPa to 700 kPa and strain measurement within the range of-400 mu epsilon to + 400 mu epsilon are achieved, the sensor is smaller in size and higher in sensitivity, and application of a traditional sensor in the multi-metal environment is expanded.

Certain aspects of the present disclosure provide techniques for radio frequency identification (RFID) tag segmentation. Certain aspects provide a method for wireless communication by a first receiver, such as a passive RFID tag. The method generally includes receiving a first signal from a transmitter that initiates a first inventory check, and in response to receiving the first signal, backscattering a second signal to the transmitter, where the second signal is backscattered using a resource specific to the first receiver.

Certain aspects of the present disclosure provide techniques for wireless communications. One example method includes receiving, from a backscatter device, a spatial multiplexing capability report; transmitting, to the backscatter device, a reference signal reflection configuration; and transmitting, to the backscatter device, a transmission grant for a backscatter link.

Techniques for selecting frequencies of operation are described. HF signals may land at the receiver node with power levels dependent upon the transmit frequency. The frequency with the highest power level at the receiver node may be selected when the receiver node is not subject to interfering. The receiver node may be unable to receive a desired signal if an interfering signal has a signal level which is higher than the desired signal. The transmitter node may select a frequency which has a receiver signal level which is higher than the interfering signal for the selected frequency. The receiver node may then receive the transmit signal at the selected frequency even when subject to interfering from the interferer node.

The invention discloses a distributed intelligent metasurface cooperative communication and imaging integrated method, and belongs to the technical field of wireless communication and sensing. According to the method, a multi-antenna and multi-carrier frequency technology is adopted, and a plurality of reconfigurable intelligent metasurface RISs are utilized to cooperatively complete communication and imaging of a target region ROI. Firstly, an imaging target ROI is divided into a plurality of space grid units, and equivalent scattering coefficients of all the units form a vector to serve as a solving target. A plurality of RISs are installed at different positions of the ROI near field. Secondly, transmitting pilot signals for a plurality of times, and configuring different RIS phases; then, a receiving end obtains overall channel state information by using a channel estimation algorithm, and extracts channel components which finally reach a receiving antenna from a transmitting antenna through the ROI and the RIS in sequence; and finally, obtaining a sensing matrix, solving an equivalent scattering coefficient of the ROI unit by using a compressed sensing imaging algorithm, and completing target imaging.

The invention discloses a low-slow small target detection and data fusion method based on 5G signals, and relates to a low-slow small target detection and data fusion method. The invention aims to solve the problems of low detection precision and difficulty in effective identification and tracking of the low-slow small target in the prior art. According to the invention, a 5G signal retroreflection detection system with separated transmitting end and receiving end is constructed, direct wave and multipath interference are eliminated by using 5G signal code division multiple access characteristics, and target position and speed information are obtained through two-dimensional matched filtering and two-dimensional sliding correlation processing; a 5G base station forward scattering detection system is established, and target detection is realized by analyzing target forward scattering signal characteristic parameters according to the Babinet principle; a specific data fusion algorithm is adopted to carry out fusion processing on heterogeneous data obtained by backward reflection and forward scattering, and accurate information such as target position, speed, attribute and the like is output. The invention belongs to the technical field of low-slow small target detection.

Systems, methods, apparatus, and computer program products for a mode switching scheme for reconfigurable intelligent surface (RIS) assisted backscatter communication. The method may include connecting with a network node for communication; receiving an indication of an activation of backscatter from the network node; receiving a backscatter signal and a signal sent by a network node; and demodulating the backscatter signal and a signal transmitted by the network node, the backscatter signal comprising backscatter data.

This application discloses a method and apparatus for backscatter signal transmission, a communication device, and a readable storage medium. The method includes: determining, by a tag based on first information, a parameter related to transmission of a backscatter signal; where the first information includes at least one of the following: a first identifier, where the first identifier includes an identifier of the tag or a temporary identifier of the tag; a first value, where the first value is used to indicate a random number generated by the tag; a second value, where the second value is used to indicate a counter value of the tag; a third value, where the third value is used to indicate a counter step of the tag; a group identifier or intra-group identifier of the tag; a session number or a process number; or information received from a reader / writer.

The invention discloses an ultra-low power consumption LoRa backscatter communication system based on an FPGA (Field Programmable Gate Array) and a design method thereof. Comprising a LoRa transmitter, a LoRa receiver, an upper computer and a LoRa backscattering terminal. The LoRa transmitter transmits a sine wave signal with a certain frequency. And the LoRa receiver receives and demodulates the backscattering signal, and then sends the demodulated signal to the upper computer. And the upper computer receives the demodulated signal, completes audio decompression and plays the audio. According to the backscattering terminal, an FPGA serves as a master control, and the FPGA completes the functions of audio compression, LoRa physical layer protocol processing and a LoRa backscattering algorithm. According to the invention, a LoRa backscattering algorithm based on table look-up is designed, then a multi-clock design method and a clock gating technology are provided to optimize system power consumption and communication performance, and outdoor testing is carried out on a scattering terminal. According to the invention, the performance advantages of the FPGA are exerted, and the ultra-low power consumption of the terminal is maintained.

Provided are an information reporting method and apparatus, an information receiving method and apparatus, a terminal, and a network-side device. The information reporting method includes: receiving, by a terminal, a backscatter signal from a backscatter communication BSC device, determining first information based on the backscatter signal, and reporting the first information. The first information includes at least one of the following: content of the backscatter signal, first indication information, and information of a first event. The first indication information is used to indicate whether a target event occurs when the terminal receives the backscatter signal within first time, and the first event is a target event that occurs when the terminal receives the backscatter signal within the first time.

The present application belongs to the technical field of communications. Disclosed are transmission parameter determination methods, an apparatus, a device, and a readable storage medium. A method comprises: a responder device checking a resource group set bearing downlink control signaling; and the responder device determining a back transmission parameter according to the number of resource groups contained in the resource group set, the corresponding relationship between the number of the resource groups contained in the resource group set and the back transmission parameter being indicated by a read-write device or being predefined by a protocol, and the back transmission parameter comprising at least one of the following: the power of a signal transmitted by the responder device, the rate of data transmitted by the responder device, the number of information bits transmitted by the responder device, and the type of information transmitted by the responder device.

The invention discloses a sensing equipment selection method and device and related equipment, and belongs to the technical field of communication, and the method comprises the steps that first equipment obtains at least one measurement value of a first target index, the at least one measurement value comprises a measurement value obtained by performing first measurement by at least one first node based on a first signal sent by at least one second device; the first device determines a second device of a target type for performing a perceptual operation based on at least one measurement of the first target indicator.

Method and apparatus for passive or semi-passive nodes having polarization conversion capability. The apparatus provides, to a passive node or a semi-passive node, an access control indication that indicates support for at least one of a first mode of operation or a second mode of operation. The apparatus monitors for a backscattered signal from the passive node or the semi-passive node that is supported by the access control indication, where the backscattered signal comprises the first mode of operation. The apparatus communicates with the passive node or the semi-passive node in response to the first mode of operation of the backscattered signal actively supported by the access control indication.

Provided are a transmission method for ambient backscatter, a communication apparatus, and a storage medium. The transmission method comprises: an ambient backscatter function module in a core network transmits information related to an ambient backscatter service.

Systems, methods and apparatuses herein provides ways to handle interference to a backscattered signal carrying information from an ambient internet of things (IoT) device. The interference may be from the carrier wave that is used for providing energy to the device. In some embodiments, sequence-based interference handling may be used to minimize the carrier wave interference. In some embodiments delay-based Interference handling may be used to minimize the carrier wave interference.