37 results about "Channel knowledge" patented technology

A bidirectional signal processing method uses parallel transmission of digital transmitted data streams in a multiple input-multiple output system. Related art methods generate high bit error rates mostly in singular transmission channels. For this reason, the rank-adaptive signal processing method provides that the number n_d of active subchannels are varied according to the actual channel behavior in order to effect a robust data transmission even in singular radio channels based on a transmit-side and receive-side channel knowledge and a modification of the data vector by a linear matrix vector multiplication while introducing a factor gamma for limiting the maximum transmit power. The maximum transmit power is then only distributed to the currently activated subchannels so that no transmit power remains unused. Another optimization of the number of subchannels n_d occurs when selecting the modulation and encoding methods. During the optimal rank-adaptation according to the water-filling principle, another power is allocated to each subchannel. Another modulation and encoding method is accordingly selected for each data stream. During the suboptimal rank-adaptation according to the channel inversion principle, all subchannels have the same power whereby enabling the data streams to be modulated and encoded in a common source

A method and system for beamforming with partial channel knowledge comprises beamforming one or more streams from a beamformer to one or more receive antennas of a beamformee whose channels are known to the beamformer. In response to the beamformer having a larger number of streams to transmit to the beamformee than a rank of a partial channel matrix between the beamformer and the beamformee, beamforming is used to steer remaining streams through a null space of the partial channel matrix.

A system and method for transmitter and receiver operation for multiple-input, multiple-output (MIMO) communications based on prior channel knowledge are provided. A method for receiver operations includes receiving a data block, determining if there is confidence in information related to a channel, detecting data in the data block with a first detector in response to determining that there is confidence in the information, and detecting the data in the data block with a second detector in response to determining that there is no confidence in the information. The data block is received over the channel.

The invention discloses an interactive matting method, a medium and a computer device. The foreground sample space and background sample space are obtained by human-computer interaction. According toa marking operation instruction, smearing a hair region of the original image to mark an unknown region; Obtaining pixels of each unknown region, traversing all sample pairs according to each pixel ofthe unknown region to select a sample pair with the smallest total cost function value, and calculating an alpha value corresponding to each pixel of the unknown region according to the selected sample pair; The alpha mask image is obtained according to the alpha value corresponding to each pixel of the unknown region, and the alpha mask image is denoised to obtain the final alpha mask image; andthe alpha mask image is denoised to obtain the final alpha mask image. Thus, sample pairs and unknown regions can be determined through simple interaction, and the alpha value of pixels in the unknown regions can be calculated according to the sample pairs, so that users can complete accurate matting of hair edges without mastering rich PS technology and color channel knowledge.

A method and apparatus for an access point (AP) accessing a channel occupied by a neighboring AP within clear channel assessment (CCA) range. The method is implemented by setting a transmit null towards the neighboring AP, while acquiring accurate channel knowledge with minimal bandwidth penalty to surrounding networks, via a combination of sparse explicit sounding, and a following implicit channel estimation of the neighboring APs for updating the explicit data achieved by the sparse explicit sounding. An AP implementing the method is also disclosed.

A method of one AP accessing a channel occupied by a neighboring AP within CCA range, by acquiring channel knowledge via performing cooperative sounding and setting a null towards the neighboring AP, under certain conditions verifications, is provided herein. The method may include: transmitting and receive signals via a plurality of radio circuitries connected to plurality of antennas; monitoring signals received by the radio circuitries and generating a list of neighboring co-channel access points that each has plurality of antennas and are further located within a clear channel assessment (CCA) range of the access point; and instructing the radio circuitries to transmit a sounding sequence to the list of neighboring access points, and receive Channel State Information (CSI).

Differential unitary space-time (DUST) communication is a technique for communicating via one or more antennas by encoding the transmitted data differentially using unitary matrices at the transmitter, and decoding differentially without knowing the channel coefficients at the receiver. Since channel knowledge is not required at the receiver, DUST is ideal for use on wireless links where channel tracking is undesirable or infeasible. Disclosed are a class of Cayley codes for DUST communication that can produce sets of unitary matrices that work with any number of antennas, and has efficient encoding and decoding at any rate. The codes are named for their generation via the Cayley transform, which maps the highly nonlinear Stiefel manifold of unitary matrices to the linear space of skew-Hermitian matrices. The Cayley codes can be decoded using either successive nulling/cancelling or sphere decoding.

A system for acquiring channel knowledge and a method thereof are provided. At least one transmitter generates multiple directional beams in different directions, next modulates the directional beams in the different directions by means of at least one spreading sequence, so as to enlarge the beam range of each directional beam in the different directions and use the modulated directional beams as training-specific beams in the different directions, and sweeps the training-specific beams in the different directions by means of a plurality of antennas, so that at least one receiver measures at least one training-specific beam, and determines the channel knowledge according to the measurement result and beam-related information associated with the at least one training-specific beam, so as to achieve a technical effect of reducing training overhead.

The invention discloses a channel knowledge map construction method based on an expectation maximization algorithm. The method comprises the following steps: obtaining channel knowledge data of a local communication environment through any mode of offline ray tracing simulation, offline field measurement or online real-time measurement; carrying out statistical modeling on related channel knowledge according to expert knowledge, estimating K-class parameters of a mixed statistical model by using an EM algorithm, and constructing a channel knowledge map reflecting a local signal propagation environment; and when a user needs to communicate, obtaining real-time position information through GPS, Beidou, cellular positioning, laser radar and self-sensor positioning modes, and obtaining channel knowledge of a target position by using the previously constructed channel knowledge map and a mode based on inverse distance weighting. Therefore, the method is used for environment perception adaptive communication. According to the invention, the problems of low accuracy, large data storage capacity demand and high training complexity of a channel prediction method based on a pure model or pure data are solved, so that the cost for acquiring real-time channel state information is reduced.

The embodiment of the invention provides a recognition method and a recognition device for a non-standard channel name. The method comprises the steps of if a speech control text input by a user does not include a standard channel name and matched with a preset channel name template, acquiring a target attribute keyword included in the speech control text according to the preset channel name template, wherein the target attribute keyword and the keyword in the preset channel name templates are the same in attribute; and querying a preset channel knowledge graph according to the target attribute keyword to determine the channel name included by the speech control text, thus allowing a smart television to be switched to a channel indicated by the channel name from the current playing channel. According to the recognition method and the recognition device for the non-standard channel name provided by the embodiment of the invention, a recognition rate of the non-standard channel name during a speech interaction process can be improved, and user experience can be enhanced.

The disclosure relates to a receiver (400), including: a decoder (305) comprising an adjustable receive filter (319) for decoding a receive signal (Y) received over a communication channel; and a first channel state information (CSI) handler (401) configured to provide the decoder (305) with receive-side channel state information (H-~) indicating a receive-side estimate of a channel state (H) of the communication channel and to provide the decoder (305) with transmit-side channel state information (H-hat) indicating a transmit-side estimate of the channel state (H) of the communication channel, wherein the decoder (305) is configured to adjust the receive filter (319) based on the transmit-side channel state information (H-hat) if the transmit-side channel state information (H-hat) is a less good estimate of the channel state (H) of the communication channel than the receive-side channel state information (H-~). The disclosure further relates to a precoding system (500) including suchreceiver (400).

The invention relates to the technical field of semi-supervised node classification, in particular to a node classification method based on dual-channel knowledge distillation, and the method comprises the steps that a dual-channel teacher model and a corresponding student model are set; during training, the two-channel teacher model learns knowledge information of a spatial topological structure and knowledge information of node and neighbor node feature attributes, and instructs the student model to train based on knowledge levels corresponding to the two kinds of knowledge information, so that the student model keeps structure-based priori knowledge and feature-based priori knowledge; during testing, the trained student model is used for node classification. According to the node classification method based on dual-channel knowledge distillation, the knowledge comprehensiveness and classification accuracy of the student model can be improved, so that the classification effect of node classification is assisted to be improved.