305results about How to "Improve throughput performance" patented technology

A method for conveying digitally encoded data within a Wireless Local Area Network (WLAN) using a contention based Media Access Control (MAC) protocol. In the method, a multi-beam access point can transmit a channel contention request and responsively receive channel contention responses. A set of nodes can be determined based upon the channel contention responses. Each node of the determined set can be assigned one beam of the multi-beam access point. The nodes can use the assigned beams to simultaneously communicate with said multi-beam access point in a collision-free fashion along an assigned beam.

An access node of a communication system is configured to control crosstalk between channels of the system. Vectoring circuitry in the access node estimates crosstalk between channels of the system, generates a compensation matrix based on the crosstalk estimates, and generates compensated signals based on the compensation matrix. The compensation matrix, which may be a precoder matrix or a postcoder matrix, is generated using a multiplicative update process in which a previous version of the compensation matrix comprising one or more non-zero off-diagonal elements is updated by at least one of pre-multiplying by a first auxiliary matrix and post-multiplying by a second auxiliary matrix, with a given one of the auxiliary matrices also comprising one or more non-zero off-diagonal elements. The compensated signals may be pre-compensated signals or post-compensated signals.

A wireless communication network and method are described for enhancing cell-edge performance of a wireless transmit/receive unit (WTRU). The WTRU may establish a connection with a plurality of sites via respective downlinks (DLs). Each DL may include at least one DL component carrier (CC) that operates on a frequency that is the same or different than one or more of the other CCs. The sites may manipulate their transmit power for a particular CC operating frequency such that the distance from a particular one of the sites to its cell boundary may become larger by increasing its transmit power on the particular frequency, and the distance from at least one of the other sites to its respective cell boundary may become smaller by decreasing its transmit power on the particular frequency. Thus, a coverage overlap between different CC frequencies may be created while maintaining a frequency reuse pattern of one.

The invention discloses a millimeter wave large-scale MIMO system multi-user transmission method based on space division multiple access and interference suppression. A base station is provided with a millimeter wave large-scale uniform panel antenna array; a plurality of single-antenna users receive service from the base station on the same time-frequency resource; according to information of wave beam clusters selected by the users, a universal user set is divided into an interference-free user subset and an interference user subset; the space division multiple access transmission method based on double-layer pre-coded codes is adopted to the interference-free user subset, and the transmission method based on interference suppression is adopted to the interference user subset. According to the method, the advantages of two traditional multi-user transmission methods based on space division multiple access and interference suppression respectively are combined, and the bottleneck that in an FDD transmission mode, downlink channel information of a large-scale MIMO system is difficult to obtain is broken through; meanwhile, the computation complexity problem is solved, it is guaranteed that all the users can receive the service from the base station simultaneously, and considerable system performance and speed performance are achieved at limited feedback quantity.

The invention relates to a spatial-orthogonality-based large-scale MIMO system pilot frequency distribution method. The method comprises the following steps: 1) obtaining the statistical covariance matrix information of every user terminal channel through a base station; 2) under the condition that the statistical covariance matrix information is known, obtaining the condition for achieving no-speed-loss transmission when two users located in different cells on the same time-frequency block perform pilot frequency multiplexing; 3) according to the information obtained in step 1), contrasting and calculating the spatial orthogonality degree among the channels of different users through the base station, and utilizing the condition of achieving the no-speed-loss transmission in step 2) to perform greedy packet scheduling on the users under the principle of maximizing the system sum speed; and 4) performing pilot frequency distribution on every user group. Under the condition that the user side does not know instantaneous channel state information, the spatial-orthogonality-based large-scale MIMO system pilot frequency distribution method can achieve the pilot frequency multiplexing and meanwhile effectively reduce the influence caused by the problem of pilot frequency pollution and improve the system throughput performance.

The present application provides a method and device for processing inter-subframe service load balancing and processing inter-cell interference, which includes: when processing the inter-subframe service load balancing, determining a service load of a link in a time period; determining a resource utilization ratio threshold according to the service load; and transmitting service data in each subframe according to the utilization ratio threshold. The inter-subframe service load balancing is processed when the inter-cell interference is processed, and in combination with various inter-cell interference coordination technologies, interference mitigation in one of a frequency domain, power and a space domain or the combination thereof is processed by the interference coordination technology. The present application can relieve the phenomenon that the interference mitigation effect is not good as the load information can not adapt well to the dynamic change of the inter-subframe service load in a time division duplex system, and can further mitigate the inter-cell interference in a long term evolution system, and improve the entire throughput performance of the system and the service quality of the subscriber in the system.

A feedback link between a receiver and a transmitter in a multiple antenna communication system is used to control the transmission rate and thereby improve system throughput performance.

An ATM switch supporting multicast transmissions and efficient transmission of frames. A cell is received on a multicast connection and transmitted on several branches/ports. Instead of copying a multicast cell several times for each output branch, only one copy of each multicast cell is maintained. The cell order and the stored cell data form a physical queue. Several logical queues are maintained, one for each output branch. In one embodiment, linked lists are used to maintain the queues. A cell in the physical queue is deleted after all logical queues traverse that cell. A shared tail pointer is used for all the logical queues to minimize additional processing and memory requirements due to the usage of logical queues. The queues enable cells forming a frame to be buffered until the end of frame cell is received, which provides for efficient handling of frames.

An opportunistic hybrid-relay selection scheme for downlink transmission selects between cooperative relay and single relay schemes based on the channel conditions (e.g., signal-to-noise-ratio (SNR)) between the base station (BS) and RSs (i.e., BS-RSs link) and RSs and mobile station (MS) (i.e., RSs-MS link), respectively. In another selection scheme, a selection between the single relay (e.g., best-relay) transmission scheme or the cooperative-relay transmission scheme may be determined based on transmission paths (e.g., line-of-sight, obstructed-light-of-sight, non-light-of-sight) and channel conditions (e.g., SNR) between the BS-RSs link and the RSs-MS link, respectively.

Each radio station can manage a plurality of channels, and functions both as a master station which controls transmission in each channel and a slave station which operates under control of a master station. In case of a master station, it transmits a signal under control of the own station, and in case of a slave station, it transmits a signal under control of the master station. Each radio station can communicate with any other radio station either directly or through another radio station. In each channel, communication is carried out in time division of centralized control access phase and distributed control access phase. A master station in case of centralized control access phase is determined in each channel and in each link.

The invention discloses a method for multi-user dispatching transmission based on 3D-MIMO codebook design. The method comprises the steps that an even flat board array is adopted by a base station antenna, a direct product codebook for 3D-MIMO is adopted, a horizontal codebook in the direct product codebook is a DFT codebook, and a vertical codebook is obtained through space division; the codebooks are grouped according to basic beam directional diagrams corresponding to codons in the direct product codebook, and the limiting feedback quantity is calculated by users according to the codebook grouping condition and a channel estimation result and is fed back to a base station through a feedback channel; the users are paired and dispatched by the base station according to the limiting feedback quantity of the users and multi-user transmission is conducted. Compared with a two-dimension codebook, a traditional three-dimensional DFT direct product codebook and multi-user transmission methods of the two-dimension codebook and the traditional three-dimensional DFT direct product codebook, the use rate of a system frequency spectrum and the handling capacity performance are improved.

The invention belongs to the field of communication technology, and relates to a full-duplex environment backscattering communication system, a transmission method and a resource allocation method. According to the system of the invention, a full-duplex-type access point is configured with one or more antennas, and two modes of channel estimation and full-duplex backscattering communication are included; in a channel estimation mode, the access point sends a downlink pilot signal, a plurality of backscattering devices carry out backscattering by respective fixed backscattering coefficients according to a manner of division multiplexing, the access point estimates channels of all the backscattering devices, and a traditional user utilizes the received pilot signal to estimate a downlink channel thereof; and in a full-duplex communication mode, the access point sends a downlink data signal, the traditional user uses the estimated downlink channel to carry out signal receiving detection,the backscattering devices select backscattering coefficients according to information bits for backscattering, and the access point detects signals of the backscattering devices. The system can be used in a variety of low-power-consumption Internet-of-things communication scenes, and has higher practicability.

A method for determining an aging period for retaining a write-back data in a cache memory prior to writing the write-back data to a storage media is determined through use of a write-back aging routine. The aging period is based on a proportional utilization level of the cache memory by the write-back data, the higher the memory utilization level, the shorter the period for aging the write-back data. The aging period takes a form of an aging threshold, which differs depending on the memory utilization level, i.e., the amount of cache memory utilized by the write-back data.

The method includes, identifying the memory utilization level, selecting the data aging threshold based on the memory utilization level; and writing the data from the cache memory to the storage media when an age of the data in the memory exceeds the selected data aging threshold.

The invention discloses a software defined network controller system in named data networking and a method thereof. A control plane and a data plane of the named data networking are separated by the system. The software defined network controller system comprises a storage module which is used for storing the data plane and maintaining four data structures of the data plane including a topological structure, a rule table, a push table and a routing table, wherein the control plane utilizes the data structures to control forwarding of data flow in the named data networking; a communication module which utilizes a customized communication format to establish connection between a software defined network controller of the control plane and network equipment of the data plane, maintain connection and receive and process data flow transmitted by the named data networking; and a function module API which is used for packaging functions of the storage module and is utilized to operate the storage module by an application layer so that direction of data flow is controlled.

Encapsulating packets into a frame includes receiving the packets at a station of a number of stations of a network. Each packet is associated with a delay requirement that reflects a deadline corresponding to at least one of the stations. The packets are directed to queues of the station. An available channel of the network is detected. It is determined that one or more packets at a queue are ready to be encapsulated into a frame in accordance with the delay requirements. The one or more packets are encapsulated into the frame for transmission using the available channel.

This invention relates to a channel coding link process method of wireless physical layer including: carrying out Turbo coding to information block bit data, carrying out rate match to the Turbo coded code bit based on circulation buffer storage, and bit priority mapping modulation to the system bit stream and verified bit stream.

The invention relates to a high throughput WLAN (Wireless Local Area Network) Mesh network rate selection method. A terminal firstly distinguishes impact loss from noise jamming loss according to a selected data sending mode; the loss is distinguished by adding negative frame NACK (Negative Acknowledgement) for a basic access mode, and the loss is distinguished by the sending and receiving conditions of an acknowledgement frame ACK and a clear-to-send frame CTS for an RTS/CTS (Request To Send/Clear To Send) mode. The accurate estimation of channel state is realized on the basis of self learning of local information of a local MAC (Media Access Control) layer acknowledgement frame to instruct the selection of the rate of a physical layer. The terminal utilizes the maximum system throughput as a target function by maintaining a rate selection probability vector. When each rate in the system is selected for certain times, the terminal starts to update the probability vector so as to ensure the astringency and the stability of the rate selection algorithm, and then, the terminal selects any one rate for data transmission with the probability in the probability vector.

An object of the present invention is to improve efficiency of transfer of control information, graphic data, and the like for drawing and display control in a graphic data processor. A graphic data processor includes: a CPU; a first bus coupled to the CPU; a DMAC for controlling a data transfer using the first bus; a bus bridge circuit for transmitting/receiving data to/from the first bus; a three-dimensional graphics module for receiving a command from the CPU via the first bus and performing a three-dimensional graphic process; a second bus coupled to the bus bridge circuit and a plurality of first circuit modules; a third bus coupled to the bus bridge circuit and second circuit modules; and a memory interface circuit coupled to the first and second buses and the three-dimensional graphic module and connectable to an external memory, wherein the bus bridge circuit can control a direct memory access transfer between an external circuit and the second bus.