Abstract: A wireless communication system non-collaborative, multiple input, multiple output (MIMO) space division multiple access (SDMA) system determines subscriber station combining and weighting vectors that yield a high average signal-to-interference plus noise ratio (SINR). Each subscriber station independently transmits information to a base station that allows the base station to determine a weight vector wi for each subscriber station using the determined combining vector of the subscriber station. The ith combining vector corresponds to a right singular vector corresponding to a maximum singular value of a channel matrix between a base station and the ith subscriber station. Each subscriber station transmits signals using a weight vector vi, which corresponds to a left singular vector corresponding to a maximum singular value of a channel matrix between the ith subscriber station and the base station. The base station uses the weight vector wi to determine the signal transmitted by the ith subscriber station.

Abstract: A comparator (231) for determining a peak number, representing a maximum or minimum of a set of numbers, includes a multi-element comparator (232) for comparing different pages of the set of numbers in a page comparison mode to output a candidate set of winning numbers, and for automatically switching to a leaf/tree search of the candidate set of winning numbers in an element comparison mode. Operating in parallel with the multi-element comparator (232), an index generation unit (233) processes flag/sign bits from the multi-element comparator in conjunction with state machine control logic (230) to keep track of the index/indices for the peak value. Upon completion of final stage, the index generation unit returns the absolute index (235) of the peak value.

Abstract: A method and apparatus for a radio base station (200) generates a multicarrier communication signal having a reduced crest factor by processing a block of samples (231) with a peak search window (271) to identify and suppress signal peaks exceeding a power threshold value.

Abstract: A wireless communication system non-collaborative, multiple input, multiple output (MIMO) space division multiple access (SDMA) system determines subscriber station combining and weighting vectors that yield a high average signal-to-interference plus noise ratio (SINR). Each subscriber station independently transmits information to a base station that allows the base station to determine a weight vector wi for each subscriber station using the determined combining vector of the subscriber station. The ith combining vector corresponds to a right singular vector corresponding to a maximum singular value of a channel matrix between a base station and the ith subscriber station. Each subscriber station transmits signals using a weight vector vi, which corresponds to a left singular vector corresponding to a maximum singular value of a channel matrix between the ith subscriber station and the base station. The base station uses the weight vector wi to determine the signal transmitted by the ith subscriber station.

Abstract: A method and apparatus may be used to evaluate a polynomial by initializing a multiply and accumulate feedback apparatus (260) comprising a multiplier stage (264) having an output coupled to an input of an accumulator stage (267) having an accumulator feedback output (269) selectively coupled to an input of the multiplier stage over a plurality of clock cycles; iteratively calculating a final working loop variable z over an additional plurality of clock cycles; multiplying the final working loop variable z and a complex input vector x to compute a final multiplier value; and adding a least significant complex polynomial coefficient to the final multiplier value using the multiplier stage of the multiply and accumulate feedback apparatus to yield a result of the polynomial evaluation.

Abstract: A multi-user multiple input, multiple output (MIMO) downlink beamforming system is provided to enable transmit beamforming vectors to be efficiently provided to a subset of user equipment devices, where spatial separation or zero-forcing transmit beamformers (wi) are computed at the base station and used to generate precoded reference signals. The precoded reference signals are fed forward to the user equipment devices, which apply one or more hypothesis tests to the precoded reference signals to extract the precoding matrix (W), including the specific transmit beamforming vector (WUE) designed for the user equipment, and this extracted information is used to generate receive beamformers (vi).

Abstract: A multi-user multiple-input multiple-output (MIMO) downlink beamforming system with limited feed forward is provided to enable precoding matrix information to be efficiently provided to a subset of user equipment devices, where zero-forcing transmit beamformers are computed at the base station and assembled into a precoding matrix. The precoding matrix is encoded using a compact reference signal codebook for forward link signaling, either by sending bits indicating the index of the transmission matrix used, or by transmitting one or more precoded pilots or reference signals wherein the pilot signals are precoded using vectors uniquely representative of the transmission matrix used which includes candidate reference signal matrices which meet a predetermined condition number requirement, such as a condition number threshold. The precoding matrix information is extracted at the user equipment devices using the compact reference signal codebook and used by the MMSE receiver to generate receive beamformers.

Abstract: A comparator (231) for determining a peak number, representing a maximum or minimum of a set of numbers, includes a multi-element comparator (232) for comparing different pages of the set of numbers in a page comparison mode to output a candidate set of winning numbers, and for automatically switching to a leaf/tree search of the candidate set of winning numbers in an element comparison mode. Operating in parallel with the multi-element comparator (232), an index generation unit (233) processes flag/sign bits from the multi-element comparator in conjunction with state machine control logic (230) to keep track of the index/indices for the peak value. Upon completion of final stage, the index generation unit returns the absolute index (235) of the peak value.

Abstract: Various methods of allocating uplink control channels in a communication system are implemented at a resource scheduler or a user equipment (UE). In one method the scheduler reserves resources for a downlink data channel and signals a corresponding downlink data channel grant and also reserves resources for a persistent uplink control channel for a longer duration than the data channel grant. Signaling overhead associated with a grant for this persistent uplink control channel is reduced over a full dynamic grant. A predetermined rule can be used at the scheduler and at the UE to avoid overhead signaling associated with a grant for this persistent control channel. Predetermined rules at the UE and scheduler can also be used to reserve appropriate resources and select appropriate MCS levels for control information and the control information and uplink data can be transported over a common uplink channel when a time overlap occurs between an uplink data channel and the persistent control channel.

Abstract: A wireless communication system non-collaborative, multiple input, multiple output (MIMO) space division multiple access (SDMA) system determines subscriber station combining and weighting vectors that yield a high average signal-to-interference plus noise ratio (SINR). Each subscriber station independently transmits information to a base station that allows the base station to determine a weight vector wi for each subscriber station using the determined combining vector of the subscriber station. The ith combining vector corresponds to a right singular vector corresponding to a maximum singular value of a channel matrix between a base station and the ith subscriber station. Each subscriber station transmits signals using a weight vector vi, which corresponds to a left singular vector corresponding to a maximum singular value of a channel matrix between the ith subscriber station and the base station. The base station uses the weight vector wi to determine the signal transmitted by the ith subscriber station.

Abstract: A method and apparatus may be used to evaluate a polynomial by initializing a multiply and accumulate feedback apparatus (260) comprising a multiplier stage (264) having an output coupled to an input of an accumulator stage (267) having an accumulator feedback output (269) selectively coupled to an input of the multiplier stage over a plurality of clock cycles; iteratively calculating a final working loop variable over an additional plurality of clock cycles; multiplying the final working loop variable z and a complex input vector x to compute a final multiplier value; and adding a least significant complex polynomial coefficient to the final multiplier value using the multiplier stage of the multiply and accumulate feedback apparatus to yield a result of the polynomial evaluation.

Abstract: Various methods of allocating uplink control channels in a communication system are implemented at a resource scheduler or a user equipment (UE). In one method the scheduler reserves resources for a downlink data channel and signals a corresponding downlink data channel grant and also reserves resources for a persistent uplink control channel for a longer duration than the data channel grant. Signaling overhead associated with a grant for this persistent uplink control channel is reduced over a full dynamic grant. A predetermined rule can be used at the scheduler and at the UE to avoid overhead signaling associated with a grant for this persistent control channel. Predetermined rules at the UE and scheduler can also be used to reserve appropriate resources and select appropriate MCS levels for control information and the control information and uplink data can be transported over a common uplink channel when a time overlap occurs between an uplink data channel and the persistent control channel.

Abstract: A multi-user MIMO downlink beamforming system is provided to enable transmit beamforming vectors to be efficiently provided to a subset of user equipment devices, where spatial separation or zero-forcing transmit beamformers (wi) are computed at the base station and used to generate precoded reference signals. The precoded reference signals are fed forward to the user equipment devices, which apply one or more hypothesis tests to the precoded reference signals to extract the precoding matrix (W), including the specific transmit beamforming vector (WUE) designed for the user equipment, and this extracted information is used to generate receive beamformers (vi).

Abstract: A multi-user MIMO downlink beamforming system with limited feed forward (200) is provided to enable precoding matrix information to be efficiently provided to a subset of user equipment devices (201.i), where zero-forcing transmit beamformers (wi) are computed at the base station (210) and assembled into a precoding matrix (W). The precoding matrix is encoded using a compact reference signal codebook (225, 207.i) for forward link signaling, either by sending bits indicating the index of the transmission matrix used, or by transmitting one or more precoded pilots or reference signals wherein the pilot signals are precoded using vectors uniquely representative of the transmission matrix used which includes candidate reference signal matrices which meet a predetermined condition number requirement, such as a condition number threshold. The precoding matrix information (227) is extracted at the user equipment devices (201.i) using the compact reference signal codebook (207.i) and used by the MMSE receiver (209.

Abstract: A method and apparatus for a radio base station (200) generates a multicarrier communication signal having a reduced crest factor by processing a block of samples (231) with a peak search window (271) to identify and suppress signal peaks exceeding a power threshold value.

Abstract: A multi-user MIMO downlink beamforming system (200) is provided to enable transmit beamforming vectors to be efficiently provided to a subset of user equipment devices (201.i), where spatial separation or zero-forcing transmit beamformers (wi) are computed at the base station (210) and used to generate precoded reference signals (216). The precoded reference signals (216) are fed forward to the user equipment devices (201.i) which apply one or more hypothesis tests (207.i, 208.i) to the precoded reference signals to extract the precoding matrix (W), including the specific transmit beamforming vector (wUE) designed for the user equipment, and this extracted information is used to generate receive beamformers (vi).

Abstract: A wireless communication system noncollaborative, multiple input, multiple output (MIMO) space division multiple access (SDMA) system determines subscriber station combining and weighting vectors that yield a high average signal-to-interference plus noise ratio (SINR). Each subscriber station independently transmits information to a base station that allows the base station to determine a weight vector wi for each subscriber station using the determined combining vector of the subscriber station. The ith combining vector corresponds to a right singular vector corresponding to a maximum singular value of a channel matrix between a base station and the ith subscriber station. Each subscriber station transmits signals using a weight vector vi, which corresponds to a left singular vector corresponding to a maximum singular value of a channel matrix between the ith subscriber station and the base station. The base station uses the weight vector wi to determine the signal transmitted by the ith subscriber station.

Abstract: A multi-user multiple input multiple output (MIMO) downlink beamforming system with limited feed forward (200) is provided to enable precoding matrix information to be efficiently provided to a subset of user equipment devices (201.1), where zero-forcing transmit beamformers (wi) are computed at the base station (210) and assembled into a precoding matrix (W). The precoding matrix is encoded using a compact reference signal codebook (225, 207.1) for forward link signaling, either by sending bits indicating the index of the transmission matrix used, or by transmitting one or more precoded pilots or reference signals wherein the pilot signals are precoded using vectors uniquely representative of the transmission matrix used which includes candidate reference signal matrices which meet a predetermined condition number requirement, such as a condition number threshold.

Abstract: A multi-user MIMO downlink beamforming system with limited feedback (200) is provided to enable precoding for multi-stream transmission, where a channel codeword (ui) and one or more channel quality indicator values (CQIA, CQIB) are computed at the user equipment (201.i) on the basis of maximizing a predetermined SINR performance metric (?i) which estimates the receive signal-to-noise-ratio (SINR) at the user equipment (201.i). The computed codeword (ui) and CQI values (or differential values related thereto) are quantized and fed back to help the base station (210) which applies a correction to the appropriate CQI value in the course of designing the transmit beamforming vectors w and determining the appropriate modulation and coding level to be used for downlink data transmission.

Abstract: In a data processing system, having a twiddle factor unit, a method for performing a mixed-radix discrete Fourier transform (DFT) having a block size, N, and a maximum block size, Nmax, wherein the maximum block size includes a radix that is not a power of 2 is provided. The method includes receiving a delta value at an input of the twiddle factor unit, the delta value representing a ratio of a modified maximum bock size to the block size, wherein the modified maximum block size is a power of 2. The method further includes using the delta value to obtain a step size for generating indices of a look-up table stored within the twiddle factor unit, wherein the look-up table stores real and imaginary components of twiddle factors corresponding to a set of block sizes of the DFT.