Abstract: In an orthogonal frequency division multiplexed (OFDM) system, a transmitter and/or receiver communicate separate data streams on non-orthogonal spatial channels. Each spatial channel may use the same set of OFDM subcarriers and may take advantage of the multipath characteristics of the spatial channel allowing the communication of additional data without an increase in frequency bandwidth. Space-frequency subcarrier modulation assignments may be dynamically assigned on a per subcarrier basis as well as a per spatial channel basis to help maximize the data-carrying capacity of the channel. In some embodiments, each of the spatial channels may be associated with one of a plurality of spatially diverse antennas. In other embodiments, beamforming may be performed to allow the transmission and/or reception of signals within the spatial channels.

Abstract: A multicarrier transmitter may transmit cyclically delayed linear combinations of two or more data streams with three or more antennas. In some embodiments, the multicarrier transmitter may transmit cyclically delayed linear combinations of three data streams with four antennas.

Abstract: An ultrawideband radio frequency pulse is generated by shaping a carrier signal having a selected frequency with a window function. The shaped carrier is gated to produce the ultrawideband pulse. In further embodiments, the window function comprises a sinusoidal function, and the ultrawideband pulse is formed via a mixer and a CMOS radio frequency switch.

Abstract: In a spatial division multiple access system that employs acknowledgements to variable length transmissions within a timeout period, a station that has completed its transmission may delay beginning the timeout period until it determines that other stations on the same channel have completed their transmissions.

Abstract: In Spatial Division Multiple Access (SDMA) communications, mobile devices that are transmitting to a base substantially simultaneously during a predetermined communications phase may wait until after an end of the predetermined communications phase to receive acknowledgments to their transmissions, so that a mobile device making a relatively short transmission does not experience an acknowledgement timeout while another mobile device is still completing a relatively long transmission. In some embodiments, the mobile devices may transmit a non-immediate block acknowledgement request during the communications phase.

Abstract: In an orthogonal frequency division multiplexed (OFDM) system, a transmitter and/or receiver communicate separate data streams on non-orthogonal spatial channels. Each spatial channel may use the same set of OFDM subcarriers and may take advantage of the multipath characteristics of the spatial channel allowing the communication of additional data without an increase in frequency bandwidth. Space-frequency subcarrier modulation assignments may be dynamically assigned on a per subcarrier basis as well as a per spatial channel basis to help maximize the data-carrying capacity of the channel. In some embodiments, each of the spatial channels may be associated with one of a plurality of spatially diverse antennas. In other embodiments, beamforming may be performed to allow the transmission and/or reception of signals within the spatial channels.

Abstract: Embodiments of the present invention provide for computing spatial covariances of intersymbol interference (ISI) and using the computed spatial covariances for ISI mitigation. Other embodiments may be described and claimed.

Abstract: A method and apparatus are disclosed to generate and/or receive ultra-wide bandwidth (UWB) pulses using a digital clock.

Abstract: Embodiments of the present invention provide methods and apparatus for wireless communication using codeword with high-rate codes. Other embodiments may be described and claimed.

Abstract: Dedicated pilot signals are transmitted from a transmitting device to a receiving device through a multicarrier MIMO channel in addition to data signals and common pilot signals. The dedicated pilot signals may be used by the receiving device to validate whether a predetermined beamforming matrix (i.e., a beamforming matrix identified by the receiving device) was used by the transmitting device to precode the transmitted data. If a different beamforming matrix was used for the preceding, the receiving device may use this matrix to demodulate the received data.

Abstract: A method and apparatus are disclosed to generate and/or receive ultra-wide bandwidth (UWB) pulses using a digital clock.

Abstract: Methods and apparatuses for reducing an amount of bandwidth required for feedback to a transmitter station in a closed-loop multiple-input multiple-output (MIMO) system are described herein. The methods may include initially measuring at a receiver station channel qualities associated with receiving signals from a transmitter station for a first and a second spatial channel, the transmitter and receiver stations employing a closed-loop MIMO system. The receiver station may then determine a first and a second channel quality indicator (CQI) based on the measured channel qualities and may then transmit to the transmitter station the first and the second CQI to directly and indirectly identify a first and a second modulation coding scheme (MCS) entry among a plurality of ordered MCS entries, respectively. The second MCS entry being one of a selected subset of lower ordered MCS entries relative to the first MCS entry.

Abstract: Methods and apparatuses for providing CQI feedback with common code rate to a transmitter station are described herein. In one implementation, the methods may include a receiver station that is communicatively linked to a transmitter station via k spatial channels transmitting a first CQI to the transmitter station that indicates a modulation level for use by the transmitter station to transmit (i.e., to configure for transmission) a first of k streams of signals to be transmitted to the receiver station. The first CQI may further include a common code rate to be used by the transmitter station for transmitting the first of the k streams of signals as well as for transmitting the rest of the k?1 additional streams of signals to the receiver station.

Abstract: Embodiments of a wireless access network and method for allocation time and frequency resources are generally described herein. Other embodiments may be described and claimed. In some embodiments, a base station allocates contiguous groups of data subcarriers of a downlink subframe to closed-loop user stations, and allocates the remaining data subcarriers of the downlink subframe to open-loop user stations to increase frequency diversity.

Abstract: Embodiments of the present invention provide for downlink resource allocation among a plurality of users. Other embodiments may be described and claimed.

Abstract: Embodiments of the present invention provide for downlink and uplink control feedback signaling. Other embodiments may be described and claimed.

Abstract: A switched antenna system selects an antenna based on symbol error rate.

Abstract: Embodiments of system and method for generating channel estimates in a wireless network are generally described herein. Other embodiments may be described and claimed. In some embodiments, a linear interpolator uses refined cross-correlation and autocorrelation estimates and pilot subcarrier estimates to generate channel estimates for the current OFDM data symbol.

Abstract: Embodiments of multiple input multiple output wireless communication systems, associated methods and data structures are generally described herein.

Abstract: A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment.