138 results about "Orthogonal frequency-division multiple access" patented technology

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 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.

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.

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.

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.

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 disclosure provides systems and methods for selectively enabling multi-user (MU) communications. In some implementations, an access point (AP) obtains one or more packets associated with a traffic flow, and obtains at least one of service-level agreement (SLA) parameters associated with the traffic flow, attributes of the traffic flow, or network parameters associated with a basic service set (BSS) that includes the AP. The AP provides an indication of whether the traffic flow is suitable for transmission as a single-user (SU) multiple-input multiple output (MIMO) (SU-MIMO) communication, as a multi-user (MU) MIMO (MU-MIMO) communication, as an orthogonal frequency division multiple access (OFDMA) communication, or as a partial bandwidth (BW) MU-MIMO communication to a WLAN subsystem of the AP, the indication being based on one or more of the SLA parameters, the traffic flow attributes, or the network parameters.

Logic to generate a 320 megahertz (MHz) extremely high throughput (EHT) physical layer protocol data unit (PPDU) comprising a multi-resource unit (MRU). Logic to generation of a non-orthogonal frequency division multiple access (non-OFDMA) 320 MHz EHT PPDU, wherein the MRU comprises a 240 MHz multi-MRU, the 240 MHz MRU comprising at least two contiguous 996 tone resource units (RUs). Logic to generation of an OFDMA 320 MHz EHT PPDU, wherein the MRU comprises at least one 996 tone RU and one 484 tone RU. Logic to cause the transmission of the 320 MHz EHT PPDU. And logic to receive and decode the 320 MHz EHT PPDU.

This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer storage media, for implementing multi-user (MU) communication in a wireless mesh network. A first mesh node or a network management unit may collect information from various mesh nodes and form MU association groups based on the information. An MU association group may include an MU group head that coordinates MU group communication to or from member mesh nodes that are in the MU association group. For example, the MU group head may coordinate orthogonal frequency division multiple access (OFDMA) resource unit allocations, or MU multiple-input-multiple-output (MU-MEMO) spatial stream configurations, among other examples. Different MU association groups may be formed for uplink or downlink traffic. The creation of MU association groups may enable a wireless mesh network to realize the advantages of MU group communication within the flexible topology of a mesh environment.

A communication method has the steps of: transmitting a signal to a device using a first resource unit (RU) in an orthogonal frequency-division multiple access (OFDMA) physical layer protocol data unit (PPDU) having a plurality of subcarriers for transmitting data, pilot symbols, or a combination thereof. The first RU is one of a plurality of RUs of the OFDMA PPDU, each RU comprises a subset of the plurality of subcarriers, and, in each RU, each pair of neighboring subcarriers thereof are separated by a substantially same number of subcarriers belonging to one or more other RUs of the plurality of RUs. In some embodiments, the subcarriers of each RU are same as those determined in accordance with a design method that shuffles the plurality of subcarriers using a relative prime interleaving method.

This invention discloses a modeling method for the phase shift model of each subcarrier in an intelligent reflecting surface (IRS)-assisted downlink orthogonal frequency division multiple access system, as well as a system optimization method. First, the IRS phase shift at multiple frequencies is calculated at a sufficient number of center frequency phase points. A quadratic function curve with coefficients related to frequency is used to fit the relationship between the phase shift and the center frequency phase shift, thus obtaining a function of the center frequency phase shift and other frequency phase shifts. Based on the designed phase shift model, an optimization problem is constructed to optimize the IRS center frequency phase shift matrix, subcarriers, and power allocation, maximizing the system's sum and rate. Finally, this invention transforms the original problem into a convex problem and solves it using successive convex approximation and alternating optimization methods. Simulation results demonstrate that, compared to optimization schemes assuming the same IRS phase shift on all subcarriers within the transmission band, the scheme optimized under the phase shift model presented in this invention achieves a higher practically achievable sum and rate under actual IRS phase shift conditions.

For example, a wireless communication device can be configured to: determine RU allocations to multiple resource elements (RUs) of multiple wireless communication stations (STAs), the RU allocation assigning RUs from the multiple RUs to STAs from the multiple STAs, wherein the size of the RUs assigned to the STAs is based at least on a service rate parameter, the service rate parameter depending on the service rate of the downlink (DL) service of the STA; and transmit multi-user (MU) DL orthogonal frequency division multiple access (OFDMA) physical layer protocol data units (PPDUs) to the multiple STAs according to the RU allocation.

The present invention relates to a wireless transmission station (110, 120), and more particularly, to a wireless transmission station (110, 120), which uses a resource unit (RU) or a multi-resource unit (MRU) in orthogonal frequency division multiplexing (OFDMA) communication or orthogonal frequency division multiple access (OFDMA) communication, and to a wireless transmission station (110, 120), which uses the resource unit (RU) or the multi-resource unit (MRU) in the orthogonal frequency division multiplexing (OFDMA) communication, and to a wireless transmission station (110, 120), which uses the resource unit (RU) or the multi-resource unit (MRU) in the orthogonal frequency division multiplexing (OFDMA) communication or the multi-resource unit (MRU) in the orthogonal frequency division multiple access (OFDMA) communication. The wireless transmission station (110, 120) is configured to allocate, based on the bit sequence, a first subset of a plurality of subcarriers of the RU or MRU as a data subcarrier for carrying modulation data, and to allocate, based on the bit sequence, a second subset of the plurality of subcarriers of the RU or MRU as an IM pilot subcarrier for carrying a plurality of predefined interference suppression (IM) pilot symbols. Furthermore, the wireless transmitting station (110; 120) is configured to permutate the plurality of subcarriers of the RU or MRU, the plurality of subcarriers comprising the first subset comprising data subcarriers and the second subset comprising IM pilot subcarriers, to obtain a plurality of permuted subcarriers of the RU or MRU.

Methods, systems, and devices for wireless communications are described. Techniques described herein provide for formulating single carrier waveforms into an orthogonal frequency-division multiple access (OFDMA) framework. To fit into the cyclic prefix OFDM (CP-OFDM) grid, a frequency domain fast Fourier transform (FFT) may be applied to the single carrier waveform, a bandwidth expansion and spectrum shaping may be applied to the output of the FFT and inverse FFT (IFFT) processing may be applied to the output of the bandwidth expansion and spectrum shaping. The output of the IFFT may then be represented in an OFDM compatible manner.

The present disclosure provides systems, methods, and apparatus, including computer programs encoded on computer storage media, for implementing multi-user (MU) communications in a wireless mesh network. A first mesh node or a network management unit can collect information from various mesh nodes and form MU association groups based on the information. The MU association groups can include a MU group leader that coordinates MU group communications to or from member mesh nodes in the MU association group. For example, the MU group leader can coordinate orthogonal frequency division multiple access (OFDMA) resource unit allocations, or MU multiple-input multiple-output (MU-MIMO) spatial stream configurations, among others. Different MU association groups can be formed for uplink traffic or downlink traffic. The creation of MU association groups can enable the wireless mesh network to realize the benefits of MU group communications within the flexible topology of a mesh environment.

Disclosed is a wireless transmission station (110) for transmitting a bit sequence to a wireless receiving station (120) by means of an orthogonal frequency division multiplexing (OFDM) communication or an orthogonal frequency division multiple access (OFDMA) communication through a channel (130) having a channel bandwidth, and a method for transmitting the bit sequence to the wireless receiving station (120) by means of the orthogonal frequency division multiplexing (OFDMA) communication or the orthogonal frequency division multiple access (OFDMA) communication. The wireless transmitting station (110) is configured to encode the bit sequence using a forward error correction (FEC) encoder to obtain an encoded bit sequence, and to fill the encoded bit sequence with FEC post-fill bits to obtain a filled encoded bit sequence, wherein the number of bits of the filled coded bit sequence is set for modulation on K subcarriers of a resource unit (RU) defined by the IEEE 802.11 standard framework.

This provides a technology for appropriately applying Distributed Tone Resource Units (DRUs) to Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA) in the Basic Service Set. [Solution] A communication device according to one aspect of the present disclosure is a communication device that functions as an Access Point (AP) as defined in the IEEE 802.11 standard series, and includes a transmission means for transmitting an information element that includes information indicating that the communication device has the capability to support Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA) using a Distributed tone Resource Unit (DRU).

This disclosure provides methods, components, devices, and systems for sounding for trigger-based ranging. Some aspects more specifically relate to a first wireless device dividing a frequency bandwidth available for ranging procedures into a plurality of subbands in accordance with orthogonal frequency-division multiple access (OFDMA) techniques. In some implementations, the first wireless device may transmit a trigger frame that assigns a subband to a respective neighbor wireless device. Each respective neighbor wireless device may transmit, during a same time occasion, a respective sounding signal via each respective subband allocated to the respective neighbor wireless device. In some implementations, the first wireless device may perform sounding procedures using combined multiple input multiple output (MIMO) and OFDMA techniques, where each neighbor wireless device may be assigned a respective spatial stream. Accordingly, the first wireless device may support sounding procedures for larger quantities of neighbor wireless devices.

The present disclosure relates generally to coding modulation techniques for use in digital communication systems such as Orthogonal Frequency Division Multiple Access (OFDMA) systems. More particularly, the present disclosure relates to methods and apparatus for multi-level encoding and decoding. Different receivers coupled to different parallel downlink channels having different channel qualities decode different received signal constellations at different levels of resolution. This allows the overall OFDMA downlink to operate at significantly higher data rates, thereby significantly improving system-level bandwidth efficiency.

The disclosure relates to a wireless communication system, and more particularly to, for example, but not limited to, Orthogonal Frequency Multiple Access (OFDMA) operation under co-existence constraint in wireless networks. A station (STA) in a wireless network, comprises at least one processor including processing circuitry, and memory storing instructions that, when executed by the at least one processor individually or collectively, cause the STA to: transmit, to an access point (AP), a first frame using a first communication protocol, the first frame indicating unavailability associated with a coexistence constraint imposed by a second communication protocol, the first frame including resource information indicating an unavailable resource, receive, from the AP, a second frame using the first communication protocol, the second frame allocating a resource that is determined to avoid interference by the coexistence constraint, and perform communication with the AP based on the allocated resource.

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.

Embodiments disclosed herein are directed to communicating time-critical ultra-low latency (ULL) data using one or more dedicated resource units (RUs). A station (STA) decodes a trigger frame received from an access point station (AP) encoded to indicate resource units (RUs) of an UL PPDU for an uplink multi-user orthogonal frequency division multiple access (UL MU OFDMA) data transmission by a first and a second station STA. The trigger frame may also be encoded to indicate configuration information for a dedicated RU for time-critical ultra-low latency (ULL) UL data. The dedicated RU may be one RU of one or more RUs of the UL PPDU that are reserved for time-critical communications. The STA may encode time-critical ULL UL data for transmission to the AP on the dedicated RU during the uplink MU OFDMA data transmission by the first and second STAs. The time-critical ULL UL data may start at any time during transmission of the UL PPDU. Medium access control layer (MAC) padding may be included in a MAC payload until the time-critical ULL UL data is available at the MAC layer of the STA.

In some aspects, the disclosure is directed to methods and systems for signaling and decoding of punctured sub-bands in a trigger-based PPDU. In one aspect, at least one of the communication interface or the processing circuitry of a wireless communication device is configured to generate a trigger frame that includes signaling indicating that at least one other wireless communication device is allowed to reduce a bandwidth of an allocated resource unit (RU) for transmitting data via a communication channel; transmit, via the communication channel, the trigger frame to at least one other wireless communication device; receive, via the communication channel and from the at least one other wireless communication device, an uplink (UL) orthogonal frequency division multiple access (OFDMA) frame including the data; and process the UL OFDMA frame including the data based on the signaling.

Systems and methods for Orthogonal Frequency-Division Multiple Access (OFDMA) optimized steering in Wi-Fi networks (10, 10A, 32). The present disclosure contemplates operation in a multiple access point network (14, 36) utilizing OFDMA technology, e.g., IEEE 802.11ax, where clients are connected to the access points considering the effect on OFDMA operation depending on where the clients are connected. That is, the present disclosure considers OFDMA operation in the context of optimization in a distributed or multiple access point network (14, 36). The optimization decision is based on capabilities of client devices and / or the access points, including OFDMA capability, MIMO capability, channel capability, etc. The optimization decision is used to select where client devices should connect, and optimization factors may include individual device throughput, joint load throughput (system capacity), fairness, etc.

The invention relates to the technical field of industrial wireless communication, in particular to a time-frequency joint calibration method based on carrier frequency offset and terminal equipment, and the method comprises the steps that the terminal equipment receives a downlink wireless frame sent by access point equipment, obtains the carrier frequency offset through a known reference signal in the frame, and transmits the carrier frequency offset to the access point equipment; the offset represents the relative deviation of the frequency of the crystal oscillator and is stored; when time synchronization calibration or uplink transmission is needed, the offset is read, and the local timestamp growth rate is adjusted or frequency pre-compensation is carried out on an uplink signal. The terminal equipment comprises a receiving unit, a processing unit, a storage unit, a reading unit, a time calibration unit and a frequency compensation unit. According to the invention, time-frequency joint calibration is realized by using single frequency offset estimation, trigger frame interaction is reduced, system control overhead and communication delay are reduced, and synchronization precision and signal orthogonality of multi-user uplink orthogonal frequency division multiple access transmission are improved.

The present disclosure describes a system for applying precise timing to a mesh wireless Wi-Fi network. Accurate timing enables multiple access points (APs) to serve a single station (STA)-when the STA is located in a wireless coverage area including more than one access point, without the need for a wireless trigger frame. Various examples are described, including the use of orthogonal frequency division multiple access (OFDMA), time division multiple access (TDMA), and multiple access point joint transmissions.

A method and device are provided for receiving and transmitting data in a wireless local area network. The device receives a Physical Layer Protocol Data Unit (PPDU) from a station across a transmission bandwidth and determines whether the station belongs to a Basic Service Set (BSS) managed by the device, based on the PPDU. When the PPDU is multi-user (MU-PPDU), the access point (AP) determines that the station does not belong to the BSS managed by the AP. Such an MU-PPDU includes a first signal field and a second signal field; the first signal field contains bandwidth information indicating the transmission bandwidth, and the second signal field contains user-specific information allocated for orthogonal frequency-division multiple access (OFDMA) transmission.