252 results about "Frequency-division multiple access" patented technology

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.

The invention provides a novel hybrid carrier multiple access scheme. According to the scheme provided by the invention, the energy propagation concept of the hybrid carrier is combined with a frequency division multiple access model, and a specific operation method and a processing flow of the hybrid carrier processing and the multiple access processing of the power signal in the sending and receiving processes are provided; and the requirements of signal anti-interference capability, transmission efficiency and multi-user and multi-time-space under an ad hoc network of a power wireless private network are met, and the method is called as hybrid carrier non-orthogonal multiple access (HC-OFDMA). Due to the fact that the energy dispersion capacity is enhanced, a plurality of users can share the same spectrum resource at the same time through non-orthogonal distribution of a power domain, the spectrum utilization rate can be remarkably improved, power distribution can be dynamically adjusted, transmission is optimized according to channel conditions of the users, more users are supported to access at the same time, the system capacity is improved, and the system performance is improved. The method is especially suitable for high-density users and large-scale Internet of Things scenes.

Method and apparatus for supporting simultaneous MultiUser (MU) Multiple-Input Multiple-Output (MIMO) operations utilizing Orthogonal Frequency Division Multiple Access (OFDMA) with Uplink OFDMA Random Access (UORA). Access Points (APs) trigger and obtain short PPDUs from the stations to learn spatial filtering patterns that are utilized in adjusting antenna phase differences to obtain minimum / maximum energy from this BSR. The APs determine favored and unfavored directions of communication, which are conveyed to non-AP UORA stations as channel estimation signals. The UORA stations base broadcasting on strengths of channel estimation signals to determine eligible UORA resource units. The UORA procedure to secondary APs allows a primary AP to trigger a UL-MU MIMO transmission with the number of spatial streams exceeding the number of antennas at the primary AP.

The present disclosure relates to a wireless communication system. Specifically, the present disclosure relates to a device and method for supporting device-to-reader frequency division multiple access (D2R FDMA) for ambient Internet of Things (Ambient IoT) communication in a wireless communication system.

A communication method has the step of: transmitting or receiving first data using a first resource unit (RU) of a plurality of first RUs in a first frequency band having a first bandwidth (BW) for orthogonal frequency division multiple access (OFDMA); wherein each of the plurality of first RUs has a plurality of subcarriers; and wherein, in the first RU, at least two neighboring subcarriers thereof are separated by one or more subcarriers belonging to one or more other first RUs of the plurality of first RUs.

An electronic device (such as an access point) is described. This electronic device transmits an orthogonal frequency division multiple access (OFDMA) frame to a recipient electronic device (such as a client or a station). The OFDMA frame includes multiple predefined resource units (RUs) allocated to the recipient electronic device in a set of predefined RUs having associated frequency bandwidths. Moreover, the multiple predefined RUs include two or more first predefined RUs having a first number of tones less than a predefined amount, or two or more second predefined RUs having a second number of tones greater than or equal to the predefined amount. For example, the predefined amount may include 242 tones. Note that the multiple predefined RUs may have the same or different numbers of tones. Moreover, the electronic may receive an acknowledgment or a block acknowledgment from the recipient electronic device.

The invention relates to a system and method for frequency domain copy mode transmission using orthogonal codes. A system for providing copy mode orthogonal frequency division multiple access transmission while maintaining a relatively low peak-to-average power ratio is disclosed. Data to be transmitted are converted into symbols, and the symbols are copied to a certain number of resource units. A phase shift is applied to a number of symbols prior to transition to the time domain for transmission. The phase shift may be removed at the receiver prior to decoding the signal into transmitted data.

The invention discloses a multi-source information fusion method based on wide-narrow band communication, and relates to the field of information fusion, and the method comprises the steps: carrying out the preprocessing of obtained multi-source heterogeneous data; extracting a text feature vector # imgabs0 # by using a pre-trained BERT network, and extracting an image feature vector # imgabs1 # by using a pre-trained convolutional neural network ResNET; the method comprises the following steps: respectively acquiring priorities # imgabs2 # and # imgabs3 # by utilizing a pre-trained bidirectional gating loop network BiGRU; a text priority threshold value # imgabs4 # and an image priority threshold value # imgabs5 # are set in a self-adaptive mode; transmitting the text data or image data of which the priority # imgabs6 # is greater than the priority # imgabs7 # or the priority # imgabs8 # is greater than the priority # imgabs9 # through orthogonal frequency division multiple access (OFDMA) by adopting a broadband channel; on the contrary, a narrow-band channel is adopted for transmission through code division multiple access (CDMA); performing sparse representation on the decoded text data and image data by using Bayes estimation, and performing data reconstruction through L1 norm minimization; and carrying out association fusion on the recovered data by utilizing an attention mechanism. Aiming at low multi-source information fusion precision in the prior art, the multi-source information fusion precision is improved.

Proposed are a method and an apparatus for receiving a PPDU in a wireless LAN system. Specifically, a receiving STA receives a PPDU from a transmitting STA via broadband communication and decodes the PPDU. The PPDU is received on the basis of an OFDMA scheme. The PPDU includes a first signal field. The first signal field includes first information on a preamble puncturing pattern for each 80 MHz band in the broadband communication. The first information consists of a 4-bit bitmap for the 80 MHz band.

A wireless communication method and apparatus in a wireless local area network (WLAN) system are disclosed. A wireless communication method according to one embodiment may include generating a high-efficiency Wi-Fi (HEW) frame including at least one of an HEW-SIG-A field and an HEW-SIG-B field which include channel information for communications according to an Orthogonal Frequency-Division Multiple Access (OFDMA) mode, and transmitting the generated HEW frame to a reception apparatus.

A wireless network interface of a first client station negotiates with an access point a first component channel of an operating channel via which the first client station is to receive wakeup frames from the access point. A wakeup radio of the first client station receives a wakeup packet from the access point. The wakeup packet spans the operating channel, which comprises at least four component channels, and one or more of the component channels within the operating channel are punctured so that the access point does not transmit the wakeup packet in the one or more component channels that are punctured. The wakeup packet includes a first wakeup frame for the first client station in the first component channel and one or more respective second wakeup frames for one or more second client stations in one or more respective second component channels.

Device, systems, and / or techniques for using sub-channel signaling information between an access point and a first station are disclosed. In one aspect, a method performed by a station (STA) includes: receiving, from a neighboring STA in an overlapping basic service set (OBSS), a physical (PHY) layer preamble that includes a signal field indicating a plurality of sub-bands and associated power thresholds for Uplink Orthogonal Frequency-Divisional Multiple Access (UL OFDMA) transmission, that are available for OBSS spatial reuse (SR) by the STA; and sending, to an AP with which the STA is associated, an UL OFDMA transmission using a sub-band of the plurality of sub-bands and an associated power threshold indicated in the signal field. Additional embodiments are disclosed.

The invention discloses an Internet of Vehicles secure unloading and cache optimization method based on a graph neural network, relates to the field of intelligent traffic and edge computing, and aims to solve the problems of low resource scheduling efficiency, insufficient privacy protection and task and cache processing separation of the Internet of Vehicles. The method comprises the following steps: S1, constructing an Internet of Vehicles system model, a communication model comprising a vehicle-roadside unit-macro base station architecture, an orthogonal frequency division multiple access and dedicated short-range communication protocol, and a calculation model comprising local processing and partial remote unloading; s2, Gaussian noise is introduced to realize differential privacy protection, and asynchronous federated learning is combined with a long-short-term memory network to predict task popularity; and S3, constructing a dynamic heterogeneous graph, extracting spatio-temporal features by means of a graph neural network, inputting a near-end strategy optimization algorithm, and jointly optimizing an unloading target, a proportion and a caching strategy. According to the method, the collaborative improvement of privacy security, low system total time delay, high cache hit rate and resource utilization rate is realized, and the method adapts to the dynamic topology and complex task requirements of the Internet of Vehicles.

Provided are a wireless communication terminal including: a processor; and a communication unit, wherein the processor obtains a backoff counter for an OFDMA-based random access of the terminal, wherein the backoff counter is obtained within a range of a contention window for the uplink OFDMA-based random access, receives a trigger frame indicating an uplink multi-user transmission, when one or more resource unit(s) in which random access can be performed is indicated by the trigger frame, decrements the backoff counter based on a number of resource units(s) in which random access can be performed, and when the backoff counter is 0 or decremented to 0, performs an uplink multi-user transmission through a selected resource unit among the resource units(s) and a wireless communication method using the same.

Embodiments of the present application provides system, methods and apparatus for partial long training sequence (LTS) using DRU tone plan. An orthogonal frequency division multiple access (OFDMA) frame is transmitted using a plurality of DRUs. The frame includes a scattered long training field (SLTF) portion which furthers includes one or more orthogonal frequency division multiplexing (OFDM) symbols. Each of these symbols carries a portion of the LTS using a respective DRU. At least two different OFDM symbols use different respective DRU to carry the LTS portion. Each of these symbols further carries data using another respective one or more DRUs. Transmission of this frame may inhibit LTF overhead and may allow for transmitting increased data size.

To provide a communication device, a communication method, and a program that efficiently identify a device that performs relay communication when the relay communication is used in communication between an access point and a station.SOLUTION: In a wireless communication system, a communication device that communicates with another communication device communicates data frames by selectively using a first communication method in which radio resources are allocated using at least two or more first-type resource units (RUs) each consisting of a plurality of subcarriers arranged contiguously on a frequency axis based on capability of the other communication device, and data is communicated by orthogonal frequency division multiple access (OFDMA) using the radio resources, and a second communication method in which radio resources are allocated using at least two or more second-type RUs each consisting of a plurality of subcarriers arranged so that at least some of the subcarriers are discontinuous on the frequency axis, and the data is communicated by the OFDMA using the radio resources.SELECTED DRAWING: Figure 14

The application discloses a local communication service resource isolation method and device, a storage medium and an electronic device, the method calculates resource demand and access value of a communication service based on access information of the communication service, abstracts the problem of resource allocation for the communication service based on the resource demand and the access value into a two-dimensional matrix packing problem based on an orthogonal frequency division multiple access technology, solves the two-dimensional matrix packing problem by using a pointer network and an Actor-Critic algorithm, and obtains a network slice allocation result of the communication service, so that the reasonable use of spectrum resources is realized by technologies such as OFDMA, meanwhile, the transmission of more valuable communication services is ensured by considering the resource demand and the access value during allocation, and finally, the logical isolation between communication services is realized by constructing a network slice during resource allocation of the communication services.

Systems, methods and instrumentalities are disclosed to transmission scheduling. A station (STA) in its own basic service set (BSS) receiving a transmission frame from an overlapping BSS (OBSS). The STA may decode preamble of the received transmission frame. The STA may determine, for example, using the decoded preamble that OBSS information and transmit scheme associated with the OBSS. On a condition that the transmit scheme associated with the OBSS is orthogonal frequency divisional multiple access (OFDMA), the STA in its own BSS may indicate to its access point (AP) that one or more channels or sub-channels that are available or not available for transmission. On a condition that the transmit scheme determined from the preamble of the transmission frame is orthogonal frequency divisional multiplexing (OFDM), the STA may determine that a channel is not available for transmission. The STA may set the channel to busy or idle.

An communication apparatus of the present disclosure comprises a receiver that receives a Trigger frame for allocating resource units (RUs) for random access and another frame including Random Access parameter element that comprises a first field indicating an OFDMA contention window (OCW) minimum value (OCWmin) and a second field indicating an OCW maximum value (OCWmax); and control circuitry that controls Uplink OFDMA-based Random Access (UORA) procedure using the OCWmin and the OCWmax.

The invention relates to an imitated radio frequency division multiple access method and system, and the method comprises the steps: obtaining the number of transmitting end users, and determining the number of subcarriers allocated to each transmitting end user in a DAFT domain according to the number of subcarriers in the DAFT domain; wherein the number of subcarriers allocated to each sending end user is the same; the method comprises the following steps: acquiring to-be-sent data of a sending end user, and modulating the to-be-sent data to obtain a modulation symbol vector; performing discrete affine Fourier transform on the modulation symbol vector of the sending end user to obtain an extended symbol vector multiplexed on a subcarrier; performing extension mapping on the extension symbol vector on the subcarrier according to a subcarrier mapping matrix to obtain an extended transmission symbol vector; and performing inverse discrete affine Fourier transform on the transmission symbol vector to obtain a time domain transmission signal, and sending the time domain transmission signal to a receiving end base station. According to the scheme of the invention, the interference between users can be effectively suppressed, and meanwhile, the spectrum utilization rate is improved.

An energy efficiency optimization method for multi-cell communication systems based on intelligent reflector-assisted rate division multiple access (RSMA) combines RSMA with intelligent reflector RIS. RIS intelligently regulates signal transmission links to enhance signal transmission quality, thereby improving signal quality for users at cell edges. RSMA effectively suppresses co-channel interference between users by flexibly controlling rate division strategies and beamforming. To this end, an optimization problem is constructed with the goal of maximizing system energy efficiency, jointly optimizing the beamforming vector, rate division multiple access matrix, and phase shift matrix on the base station side and the RIS side. To solve this non-convex optimization problem, an iterative solution is proposed for the beamforming, rate division, and phase shift optimization subproblems. Continuous convex optimization is used for the former, and semidefinite programming and penalty function methods are used for the latter. Compared with traditional space division multiple access and non-orthogonal frequency division multiple access, this method can achieve energy efficiency improvements of 28.5% and 10.2% for multi-cell communication systems, respectively.

According to one embodiment, a wireless communication device includes: a receiver configured to receive a first frame notifying a start of resource unit-based OFDMA (Orthogonal Frequency Division Multiple Access) communication via a first channel; and controlling circuitry configured to control, when the first frame is received, the receiver to perform standby operation at least in a first resource unit in a second channel different from the first channel, wherein the first resource unit includes one or more subcarriers among a plurality of subcarriers disposed in the second channel.

The present invention provides a multi-user downlink OFDMA configuration method. The method comprises: respectively allocating continuous resource units (RUs) included in a channel to a plurality of stations; and allocating a modulation and coding scheme (MCS) to each of the plurality of stations, wherein the data rate of the modulation and coding scheme allocated to a first station and associated with a continuous first RU allocated to the first station is monotonic, wherein the first station is included in the plurality of stations. The present invention enables the modulation and coding scheme, transmission power level and / or resource unit size to be correctly allocated, optimizes the throughput of the downlink, and improves the transmission performance.

The present disclosure provides methods, apparatuses, and systems for sharing resources of a wireless medium. Certain implementations more specifically relate to coordinated AP (CAP) time division multiple access (TDMA) and orthogonal frequency division multiple access (OFDMA) techniques for sharing time or frequency resources of a transmission opportunity (TXOP). According to such techniques, an AP that wins contention for the duration of a TXOP and obtains access to the wireless medium can share its time or frequency resources with other selected APs. To share its resources, the winning AP can divide the TXOP into multiple time or frequency segments, each time or frequency segment including corresponding time or frequency resources representing a portion of the TXOP, and allocate each of these time or frequency segments to the winning AP itself or to one of the selected APs.

A method for transmitting feedback information and a user equipment are disclosed in the present invention, wherein, one method includes: a User Equipment (UE) performing time domain extension on feedback information within one subframe; and mapping respectively data which go through the time domain extension and demodulation reference signals corresponding to the data which go through the time domain extension to multiple uplink Single Carrier-Frequency Division Multiple Access (SC-FDMA) symbols within the subframe, and transmitting the data which go through the time domain extension and the demodulation reference signals corresponding to the data which go through the time domain extension in the same frequency domain position in a way of time division multiplexing; wherein, each uplink SC-FDMA symbol occupies n successive physical resource blocks in the frequency domain, and n is a positive integer. In the present invention, the number of bits of feedback information of UE is increased, which enhances the uplink feedback capacity.

Techniques and apparatus for avoiding uplink orthogonal frequency division multiple access (OFDMA)-based random access (UORA) collisions for uplink transmissions are described. An example technique includes obtaining, by a wireless device, information indicating (i) a UORA resource unit (RU) assigned to a multi-user (MU) group including the wireless device and (ii) a number of spatial streams associated with the MU group. A respective user position associated with the wireless device within the MU group is determined from multiple user positions. A spatial stream of the number of spatial streams is selected based on the user position. Uplink data is transmitted on the UORA RU using the spatial stream.

Tone planning for wireless communications is provided. The present disclosure provides methods, devices and systems that support communication using Orthogonal Frequency Division Multiple Access (OFDMA) according to a tone plan that supports 20 MHz sub-channel puncturing within a wireless channel. In some aspects, a non-legacy tone plan may define a set of tones for resource units (RUs) such that the RUs do not overlap with 20 MHz sub-channel boundaries of a wireless channel. The position of the set of tones in the non-legacy tone plan may be shifted relative to a corresponding tone associated with a corresponding RU according to the legacy tone plan. One or more of the disclosed tone plans may enable puncturing of the sub-channels while utilizing some RUs that otherwise partially overlap with the punctured sub-channels in legacy tone plans.

The invention discloses an MIMO open-loop uplink precoding optimization system for gigabit transmission, and relates to the technical field of MIMO open-loop precoding, the MIMO open-loop uplink precoding optimization system comprises an MIMO receiving and transmitting module, an MIMO transmitter uplink module, an MIMO receiver uplink module and a simulation platform module, the MIMO receiving and transmitting module comprises components and functions of an MIMO transmitting module and an MIMO receiving module; the MIMO transmitter uplink module is divided into a phase noise test unit, a serial multi-user precoding unit and a system time delay unit; the uplink module of the MIMO receiver is divided into an SC-FDMA (Single Carrier Frequency Division Multiple Access) unit and a terminal polarization multi-antenna unit; the simulation platform module is used for building a simulation platform and accelerating a simulation process through a GPU (Graphics Processing Unit). A phase noise testing technology, a serial multi-user pre-coding technology and a frequency domain resource allocation technology in the method are closely combined with a modern information technology; the method provided by the invention can be ensured to refine the precoding selection standard for the MIMO open-loop uplink precoding optimization system for gigabit transmission in a more accurate range.

A reception method and apparatus for use in a multi-cell orthogonal frequency division multiple access (OFDMA) wireless system. In a unicast receive mode during a first receive time period, a first group of orthogonal frequency division multiplexing (OFDM) symbols is received by a mobile device from multiple of a plurality of antennas at a serving base station. In a single-frequency-network (SFN) receive mode during a second receive time period, a second group of OFDM symbols is received by the mobile device from one of a plurality of antennas at the serving base station. The transition between the first receive time period and the second receive time period occurs during a cyclic prefix or a cyclic postfix between OFDM symbols, and the plurality of antennas produce a first beam pattern during the unicast receive mode and a second beam pattern during the SFN receive mode.

This document describes methods, devices, systems, and means for a switching scheme for opting in and out of multi-user orthogonal frequency-division multiple access (MU-OFDMA). In one aspect, an electronic device (110) enters (302) the MU-OFDMA mode to communicate via a wireless network (130) over a shared-channel bandwidth. During the MU-OFDMA mode, the electronic device (110) determines (306) that an uplink-queue size is greater than a first threshold size. Responsive to the determining, the electronic device (130) opts out (310) of the MU-OFDMA mode and enters (312) a single-user mode to contend for a transmit channel for transmitting uplink data.