摘要:
Embodiments of an OFDM transmitter and method of reducing the effects of interference on subcarriers in an OFDM system by symbol loading are disclosed herein. A linear transformation is performed on a group of two or more input data symbols that are mapped to different signal dimensions to generate a corresponding two or more output data symbols. Each of the output data symbols has an increased number of constellation points. Each output data symbol is configured for transmission within one of the different signal dimensions. The linear transformation is configured so that each of the two or more output data symbols carry the information of each of the input data symbols of the group. This coding together of input data symbols that are mapped to different signal dimensions may provide improved reliability against fading and severe interference. The different signal dimensions may comprise a frequency, a time and/or a space dimension.
摘要:
An embodiment of the present invention provides a method used in transmit beam forming, comprising, providing differential feedback by using variable differential codebooks across a plurality of feedbacks wherein the differential codebooks may have different shapes, and/or spans, and/or the numbers of codewords across feedbacks.
摘要:
Feedback bandwidth may be reduced in a closed loop MIMO system by Householder transformations, vector quantization using codebooks, and down-sampling in the frequency domain. A column of a beamforming matrix is quantized using a codebook, a Householder reflection is performed on the beamforming matrix to reduce the dimensionality of the beamforming matrix, and the quantizing and performing of Householder reflection on the previously dimensionality reduced beamforming matrix is recursively repeated to obtain a further reduction of dimensionality of the beamforming matrix. These actions are performed for a subset of orthogonal frequency divisional multiplexing (OFDM) carriers, and quantized column vectors for the subset of OFDM carriers are transmitted.
摘要:
Methods and apparatus for transmitting packets in wireless communication networks are disclosed. The methods include a relay mobile station measuring channel quality between the relay mobile station and a destination mobile station in response to a request for relay mobile stations from a base station The relay mobile station reports a channel quality indicator to the base station if the channel quality for a link between the base station and the destination mobile station via the relay mobile station is greater than a predetermined channel quality. The base station determines the relay mobile station that provides an optimal route for transmitting the packets from the base station to the destination mobile station.
摘要:
A differential codebook for a wireless network includes a plurality of codewords and [e1 . . . eNs] G as a center location of the plurality of codewords, where ek represents a column vector comprising a plurality of rows including a k-th row and in which an entry on the k-th row is one and entries on each of the plurality of rows except for the k-th row are zero, where G is any Ns by Ns unitary matrix including the identity matrix, and where Ns, represents a number of spatial streams in the wireless network. At least two of the plurality of codewords are symmetric about the center location.
摘要:
A wireless network access point can operate as a closed loop MIMO device when communicating with a station that is operating as an open loop MIMO device. Transmit/receive chains in the access point are calibrated to support aggregate channel reciprocity.
摘要:
A computing platform includes a wireless interface and other devices that may cause interference to the wireless interface. The other devices may change frequencies of operation or data rates to steer signal spectrum away from current wireless channels and reduce interference to the wireless interface.
摘要:
Embodiments of multiple input multiple output wireless communication systems, associated methods and data structures are generally described herein.
摘要:
Embodiments of the present invention provide an apparatus capable of filling space-time channels in Spatial-Division Multiple-Access (SDMA) in a Medium Access Control (MAC) protocol, comprising, a base station operable in a wireless network and adapted for uplink and downlink multi-user and multi antenna operation, the base station including a MAC scheduler to schedule transmissions using packet scheduling in the wireless network, and wherein the MAC scheduler schedules variable length packets for transmission using packet scheduling in the wireless network based on transmission times to transmit on each of M spatial channels to mobile stations operable in the wireless network by filling the M spatial channels using data packets buffered for the mobile stations operable to communicate with the base station.
摘要:
Embodiments of the present invention provide an apparatus, comprising a base station operable in a wireless network, the base station including a scheduler, and wherein the scheduler schedules variable length packets for transmission based on transmission times to transmit on each of M spatial channels to mobile stations operable in the wireless network by filling the M spatial channels using data packets buffered for the mobile stations.