284 results about "Channel feedback" patented technology

In order to facilitate sending of different kinds of channel feedback information, a periodic information transmission in a shared uplink channel is configured, PUSCH, and required resources are allocated for the transmission.

A system and methodology for efficient multi-user transmission in a wireless communication with limited feedback are provided. A non-cooperative feedback-based multi-user transmission scheme is described, wherein users in a wireless communication system may independently communicate selected channel information feedback to the base station. The base station may then choose suitable precoding weights based on the received channel information feedback. An adaptive threshold-based feedback approach is also described for multi-user transmission, wherein the quality of feedback for each user can be quantified by a special threshold by the system prior to engaging in multi-user communication.

A method of Coordinated Multipoint (CoMP) communication between a base station has a plurality of points with at least one user equipment (UE). At least one UE receives at least one transmission from the base station having the plurality of points. This UE measures downlink channel state information for each of the plurality of points including a rank indicator (RI), a precoding matrix indicator (PMI) and a channel quality indicator (CQI). This UE transmits the downlink channel station information in an uplink feedback channel to the base station.

In one embodiment, a method for wireless communication includes receiving a channel feedback information from a user equipment at a base station. A control channel is allocated in a data region of a subframe as indicated by the channel feedback information. The control channel within the subframe is transmitted to the user equipment.

To provide a mobile station apparatus and a communication system that realize an efficient transmission control for a base station apparatus to allocate resources of the PUSCH with appropriate AMC mode in accordance with the channel feedback report and the scheduling request from the mobile station apparatus, and also enable rapid transmission of the uplink data (enable rapid transmission of the UL-SCH) when the mobile station apparatus transmits only the channel feedback report. A mobile station apparatus 200 applied to a system in which a base station apparatus 100 allocates the physical uplink shared channel and the mobile station apparatus 200 transmits uplink data using the physical uplink shared channel, transmits to the base station apparatus 100 the scheduling request requesting the base station apparatus 100 to allocate resources for transmitting the uplink data, using the physical uplink shared channel.

The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. Provided are a method and user equipment for sending feedback information to a base station. The method includes receiving a Channel Status Indication Reference Signal (CSI-RS) from the base station; generating feedback information on a basis of the received CSI-RS; and transmitting the generated feedback information to the base station, wherein generating feedback information includes selecting a precoding matrix for each antenna port group of the base station and selecting an additional precoding matrix on a basis of a relationship between the antenna port groups of the base station.

Methods, systems, and devices are described for wireless communication. A device may use enhanced reporting mechanisms to support control information reporting on shared spectrum. In some cases, a device may utilize enhanced component carriers (eCCs) for data transmissions. In one example, the device may transmit control information (e.g., ACK / NACK, CSI, etc.) to a corresponding device using a CCA exempt transmission (CET). In another example, a device may report control information quasi-periodically. For instance, a device may be assigned a specified interval and a control feedback window for reporting control information (e.g., CSI). The window may provide a duration prior and subsequent to the specified interval during which a UE may transmit control information. For example, the device may perform a CCA reserving the channel for a duration that does not include the specified interval but may transmit feedback information based on determining the specified interval falls within the assigned window.

A channel sounding method in a wireless local area network (WLAN) system is provided. The method, performed by a transmitter, includes transmitting a null data packet announcement (NDPA) frame to a receiver to initiate a channel sounding procedure; transmitting a null data packet (NDP) to the receiver and receiving a feedback frame. The feedback frame includes a plurality of segment frames and a channel feedback report. The channel feedback report is split into a plurality of feedback segments. Each of the plurality of feedback segments is respectively included in each of the plurality of segment frames. The each of the plurality of segment frames includes a first-segment subfield indicating whether the each of the plurality of feedback segment included is a first segment and a remaining-segment subfield indicating the number of remaining feedback segments.

Embodiments of the disclosure provide a system and method for providing channel feedback information (CFI) from a user equipment device to a base station. CFI is transmitted from the user equipment device on first and second communication channels. The user equipment device is operable to measure the channel rank of a downlink channel and to select a preferred channel rank that is used to configure the CFI that is transmitted to the base station. The base station is operable to use the preferred channel rank to interpret the CFI transmitted by the user end device.

The invention discloses a large-scale MIMO channel state information feedback method based on FCFNN, and mainly aims to solve the problems of overlarge technical feedback overhead and poor channel feedback quality in the prior art. According to the scheme, the method comprises the following steps: on a user side, performing two-dimensional discrete Fourier transform and truncation processing on adownlink channel matrix of a space-frequency domain to obtain a channel matrix H; building a channel feedback model including an encoder and a decoder, and training the channel feedback model; placingthe trained encoder and decoder on the user side and a base station side respectively; inputting the channel matrix H into the encoder to obtain a compressed vector h on the user side, and feeding back the compressed vector to a base station; inputting the h into the decoder to obtain a rebuilt channel matrix by the base station; and performing zero-padding and two-dimension inverse discrete Fourier transform on the rebuilt channel matrix to obtain an original space-frequency domain channel matrix. Through adoption of the large-scale MIMO channel state information feedback method, feedback overhead of the channel state information is lowered, and the channel rebuilding quality is improved remarkably. The large-scale MIMO channel state information feedback method can be applied to a large-scale multi-input and multi-output communication system under a frequency division duplex mode.

Power control methods and apparatus for use in a sectorized cell of an OFDM communications system are described. Each sector of a cell uses the same frequencies and transmission times and is synchronized with the other sectors in the cell in terms of tone frequencies used at any given time and symbol transmission times. Tones are allocated to channels in each cell in the same manner so that each channel in a sector has a corresponding channel in another sector. Power differences between channels in different sectors are maintained to be within a pre-selected power difference. Different channels in a cell are assigned different power levels. Wireless terminals are assigned to channels based on channel feedback information. Wireless terminals with poor channel conditions are allocated to higher power channels than wireless terminals with good channel conditions. Lower power channels often include more tones per symbol time than high power channels.

Channel feedback for non-orthogonal multiple access (NOMA) multiple-input multiple-output (MIMO) communication systems may be reported by determining a measurement set of transmission strategies for channel feedback for a non-orthogonal channel. Estimates of channel quality for downlink transmissions to the UE corresponding to respective transmission strategies of the measurement set may then be determined. A channel feedback report may then be sent. The channel feedback report may include indicators of channel quality for a subset of the measurement set of transmission strategies.

The invention provides an implicit information channel feedback method in coordinated multi-point transmission scene. In a downlink coordinated multi-point (CoMP) transmission scene, aiming at the implicit information channel feedback mechanism, the value of the channel quality indicator (CQI) or the value of the signal to noise ratio (SNR) in each district in a measurement set is fed back to a base station according to the configuration in a district in the measurement set. By adopting the technical scheme of the invention, the CQI value under the different transmission point configuration TPCC in the CoMP scene is provided for the base station fully and flexibly on the basis of ensuring small feedback quantity.

The invention discloses a power amplifier linearization correcting circuit and method based on multi-channel feedback, relates to a linearization technology in the technical field of communication, and aims to provide a power amplifier linearization correcting circuit and method capable of self-adaptively regulating a predistortion parameter of a system by tracking the linearization characteristic of a radio frequency power amplifier. The power amplifier linearization correcting method is technically characterized in that a signal output by a power amplifier is subjected to frequency spectrumdivision and is coupled to a feedback system by utilizing a plurality of paths of channels; a data recovery circuit recovers a plurality of paths of feedback information to form a path of signal; a predistortion trainer calculates the predistortion parameter by utilizing a baseband signal and a recovered feedback signal; a predistortion trainer A adds a predistortion signal complementing a nonlinear distorted signal of the power amplifier according to the predistortion parameter; and the predistortion signal in the baseband signal is counteracted in the power amplifier, thereby realizing the linearization correction of the power amplifier. The invention is mainly used for nonlinear predistortion correction of a radio frequency signal emission system.

The invention discloses a large-scale MIMO time-varying channel state information compression feedback and reconstruction method. The method comprises the steps that a channel matrix sequence is acquired, T channel matrixes are subjected to DFT separately, and a channel matrix sequence which is sparse in the angle delay domain is obtained; a channel feedback and reconstruction model CsiNet-LSTM isconstructed, the channel matrix sequence is input to a coder, and codewords are output; the codewords are sequentially input to a decoder, and a reconstructed channel matrix sequence is output; the channel feedback and reconstruction model is trained to gradually approximate to the channel matrix sequence to obtain model parameters; each channel matrix in the output reconstructed channel matrix sequence is subjected to two-dimensional inverse DFT, and a reconstruction value of an original space-frequency domain matrix sequence is obtained through recovery; and channel state information to befed back and reconstructed is input to the model, and a reconstruction value is output. According to the method, the feedback overhead of large-scale MIMO channel information can be reduced, the reconstruction precision is improved, and the excellent robustness is particularly achieved on decrease of the compression ratio.

Systems, base stations, terminals, and methods for group-selective channel feedback in a wireless communication system are described. In one signal measurement method for a base station supporting Multiuser Multiple-Input Multiple-Output (MU-MIMO), the base station allocates a group identifier to a terminal group for performing and reporting signal measurements simultaneously. When the base station transmits control information including the group identifier, each one of terminals belonging to the terminal group performs signal measurement, generates signal measurement feedback, and simultaneously transmits the signal measurement feedback to the base station.

Power control methods and apparatus for use in a sectorized cell of an OFDM communications system are described. Each sector of a cell uses the same frequencies and transmission times and is synchronized with the other sectors in the cell in terms of tone frequencies used at any given time and symbol transmission times. Tones are allocated to channels in each cell in the same manner so that each channel in a sector has a corresponding channel in another sector. Power differences between channels in different sectors are maintained to be within a pre-selected power difference. Different channels in a cell are assigned different power levels. Wireless terminals are assigned to channels based on channel feedback information. Wireless terminals with poor channel conditions are allocated to higher power channels than wireless terminals with good channel conditions. Lower power channels often include more tones per symbol time than high power channels.

The invention discloses a quantization and inverse quantization method in large-scale MIMO channel state information feedback. The method comprises the following steps: firstly, acquiring a channel matrix at a user side, and performing two-dimensional DFT on the channel matrix, so that the channel matrix in a space-frequency domain is transformed into a channel matrix sparse in an angle-time delaydomain; secondly, constructing a model Quantized-CsiNet which is subjected to quantized channel feedback and reconstruction; thirdly, training the quantized channel feedback and reconstruction model;secondly, performing two-dimensional inverse DFT on the output reconstructed channel matrix, and recovering a channel matrix reconstruction value of an original space-frequency domain; and finally, applying the trained Quantized-CsiNet model to channel state information feedback in each actual scene, and reconstructing an original channel matrix. According to the method, the quantization module and the inverse quantization module are added into the CsiNet, so that the actually transmissible channel state information bit stream can be obtained, the feedback overhead of large-scale MIMO channelinformation is reduced, the reconstruction precision is improved, and particularly, the method has excellent robustness for quantization errors.

The invention discloses a method and a system for transmitting channel feedback information, and is applied to a very high throughput (VHT) wireless local area network system. The method and the system are used for solving the problem of bandwidth selection during the channel information feedback of a receiving party and the problem of interference caused by no clear channel assessment (CCA) detection of the receiving party under the condition of an overlapping basic service set. Before a transmitting party transmits a wireless frame for requesting for the channel feedback information, at least a specified inter-frame space is required to be reserved for the CCA detection of the receiving party within the specified inter-frame space, and the receiving party performs the CCA detection before the channel feedback information is transmitted, so that a clear bandwidth in line with a protocol requirement can be selected to transmit the channel feedback information. Therefore, the problem of the interference caused by the overlapping basic service set and the problem of channel feedback bandwidth selection can be solved.

The invention provides a precoding transmission method for a multi-input and multi-output system, which comprises: a mobile station supposes an emission matrix as a unitary matrix, an MMSE receiver is used for signal combination, an equative channel is calculated, CQI and CDI are obtained and are fed back a base station; according to a channel direction index and channel quality information fed by the mobile station, the base station obtains a zero-forcing precoding emission matrix or a regulated zero-forcing precoding emission matrix corresponding to partial or total possible user combination, carries out multiuser scheduling operation and determines the scheduled user combination; and the base station utilizes the zero-forcing precoding emission matrix or the regulated zero-forcing precoding emission matrix corresponding to the scheduled user combination to carry out precoding and emission; and a scheduled user carries out MMSE receiving. The method reduces error of channel feedback, therefore effectively promoting the utilization ratio of frequency spectrum of the system.

The invention discloses a large-scale MIMO channel joint estimation and feedback method based on deep learning. The method comprises the steps: performing initial channel estimation at a user side; constructing a channel estimation subnet CEnet, and minimizing the estimation error through training; constructing a channel feedback subnet; at the user side, inputting the optimized channel estimation value, and outputting compressed code words; at the base station end, inputting the code words, and outputting the reconstructed channel matrix. And the two subnets jointly form a channel estimation and feedback joint network CEFnet. A previous CSI feedback network assumes that perfect channel state information is obtained, does not consider that a channel in practice is obtained by estimation, and has errors and noise. According to the invention, a complete downlink channel estimation and feedback process is realized by constructing a channel estimation and feedback joint network CEFnet, the purpose of eliminating errors and noise is achieved by using a brand new network architecture, and the reconstruction precision is improved while the feedback overhead is reduced.

Embodiments of the disclosure provide a system and method for providing channel feedback information (CFI) from a user equipment device to a base station. CFI is transmitted from the user equipment device on first and second communication channels. The user equipment device is operable to measure the channel rank of a downlink channel and to select a preferred channel rank that is used to configure the CFI that is transmitted to the base station. The base station is operable to use the preferred channel rank to interpret the CFI transmitted by the user end device.

The invention relates to control of link resources in a wireless telecommunications system, in which instant channel feedback information is transmitted from a mobile terminal in response to receipt of a selection message from a basestation, and the instant channel feedback information is used for real-time resource allocation and adaptation at the basestation. The feedback information includes channel quality information derived from pilot signals and from pre-allocated transmission weights.

The invention discloses a sending rate adjustment method and device based on wireless channel feedback. The sending rate adjustment method comprises the steps that a TCP connection agent entity acquires wireless channel state information; the TCP connection agent entity adjusts retransmission time out (RTO) parameters according to the wireless channel state information, the data sending rate of the TCP connection agent entity is reduced, and a device sending data to the TCP connection agent entity is notified to reduce the data sending rate. According to the sending rate adjustment method and device based on wireless channel feedback, the TCP connection agent entity can reasonably adjust the sending rate according to the wireless channel state information, channel resources obtained after modulation modes are switched can be efficiently utilized in time, and waste of radio resources can be avoided. Furthermore, blind search jitter of TCP congestion control caused by unstable wireless channels can be avoided, RTO, queue congestion and the like are avoided, and therefore wireless data service user experience is improved.

In accordance with an embodiment, a method of operating a controller in a wireless communication system includes receiving channel feedback information from a communications node, adjusting the channel feedback information based on a measurement of interference from neighboring controllers, adjusting transmit parameters of the controller using the adjusted channel feedback information, and transmitting to the communications node using the adjusted transmit parameters.

A method and system for allocating a plurality of subcarriers to a plurality of subscriber devices in a wireless network. A set of characteristics is identified (302) for a transmission on each of the plurality of subcarriers. A dynamic weight is assigned (304) to at least one subscriber device of the plurality of subscriber devices at each decision instance of the transmission corresponding to the at least subscriber device. The assignment of the dynamic weight is based on at least one of a throughput, delay, packet-loss and queue length requirement of one or more flows of the subscriber device. Further, a set of optimum values is determined (306) for the set of characteristics based on the dynamic weights and channel feedback. The plurality of subcarriers are allocated (308) to the at least one subscriber device based on at least one optimum value of the set of optimum values.

A method and apparatus for efficiently providing a large volume of channel feedback, e.g., for OFDM MISO and MIMO systems, is described herein. To that end, a mapping unit in an OFDM transceiver maps channel feedback values, e.g., received reference signal values or channel estimates derived therefrom, on a one-to-one basis to individual transmission subchannels. More particularly, the mapping unit maps a feedback value, e.g., the received reference value or a channel estimate derived therefrom, to a single transmission subchannel of an outgoing OFDM signal. For example, the mapping unit may map the feedback value to an input of a frequency transform unit, such as an inverse discrete Fourier transform unit, to map the feedback value to a single transmission subchannel comprising an OFDM transmission subcarrier. The OFDM transceiver transmits the outgoing OFDM signal to the remote transceiver to provide the feedback value to the remote transceiver.

A channel sounding method in a wireless local area network (WLAN) system is provided. The method, performed by a transmitter, includes transmitting a null data packet announcement (NDPA) frame to a receiver to initiate a channel sounding procedure; transmitting a null data packet (NDP) to the receiver and receiving a feedback frame. The feedback frame includes a plurality of segment frames and a channel feedback report. The channel feedback report is split into a plurality of feedback segments. Each of the plurality of feedback segments is respectively included in each of the plurality of segment frames. The each of the plurality of segment frames includes a first-segment subfield indicating whether the each of the plurality of feedback segment included is a first segment and a remaining-segment subfield indicating the number of remaining feedback segments.

A method and system for allocating a plurality of subcarriers to a plurality of subscriber devices in a wireless network. A set of characteristics is identified (302) for a transmission on each of the plurality of subcarriers. A dynamic weight is assigned (304) to at least one subscriber device of the plurality of subscriber devices at each decision instance of the transmission corresponding to the at least subscriber device. The assignment of the dynamic weight is based on at least one of a throughput, delay, packet-loss and queue length requirement of one or more flows of the subscriber device. Further, a set of optimum values is determined (306) for the set of characteristics based on the dynamic weights and channel feedback. The plurality of subcarriers are allocated (308) to the at least one subscriber device based on at least one optimum value of the set of optimum values.

Multipoint broadcasting requires that the downlink-channel information be available at collaborating base stations. Methods and apparatus for wideband analog channel feedback are described that provide downlink-channel information feedback from mobile users to base stations via uplink channels, and that use very few or no resources of the RAT of the wireless cellular network. Also described are methods and apparatus that perform channel-feedback signal cancellation at base stations to reduce its interference on the uplink-traffic signal. Wideband analog channel feedback is adaptable to the feedback bandwidth in uplink, and it offers frequency diversity to combat the deep fading in feedback channels. Wideband analog channel feedback is also applicable to uplink channel-information feedback. Applications of the described methods and apparatus include multipoint broadcasting in a wireless cellular network, and more generally, channel feedback between two communicating devices in a communications network.