Broadcom Corporation

Avago Technologies International Sales Pte. Limited

Avago Technologies General IP Pte, Ltd.

Pieter Roux

Vinko Erceg

Pieter Van Rooyen

Jack Winters

Severine E Catreux-Erceg

Mark Kent

Uri M Landau

Severine Catreux

Jun Zheng

Chengjin Zhang

Ning Kong

Pieter G W Van Rooyen

Pieter Gw Van Rooyen

Pieter Van Rooven

Severine Catreux-Erces

A system and method for generating weight values based on maximum data rate for weighting elements included within signal weighting and combining arrangements used in various multi-antenna transmitter and receiver structures is disclosed herein. Weighting values for a given signal combining arrangement are set so as to maximize an output data rate of the applicable multi-antenna system in the presence of adaptive bit loading of the subcarriers of a transmitted signal. The disclosed techniques may be employed to maximize a data rate of a multi-antenna communication system by using adaptive bit loading and RF and baseband weighting schemes. In this case a search is conducted over various combinations of RF and baseband weights in order to find the weight combination which, when adaptive bit loading is also employed, maximizes the data rate.

System and method for RF signal combining and adaptive bit loading for data rate maximization in multi-antenna communication systems

Methods and systems for processing signals in a receiver are disclosed herein and may include updating a plurality of filter taps utilizing at least one channel response vector and at least one correlation vector, for a plurality of received clusters, based on initialized values related to the at least one channel response vector and the at least one correlation vector. At least a portion of the received signal clusters may be filtered utilizing at least a portion of the updated plurality of filter taps. The update may be repeated whenever a specified signal-to-noise ratio (SNR) for the received signal clusters is reached. The initialized values may be updated during a plurality of iterations, and the update may be repeated whenever a specified number of the plurality of iterations is reached.

Method and system for low complexity conjugate gradient based equalization in a wireless system

A method for communication includes performing by one or more processors and/or circuits in a communication device functions including determining transmit power weights, which are to be utilized for communicating one or more wireless signals via a wireless channel, as a function of frequency of a wireless signal communicated via the wireless channel. The determining may be based on a transmission mode of the wireless signal and a state of the wireless communication channel. Transmit antenna spatial weights may be determined for communicating the one or more wireless signals via a plurality of antennas. The one or more wireless signals may be weighted with the transmit power weights and/or one of the transmit antenna spatial weights. The weighted one or more wireless signals may be transmitted via one of a plurality of antennas in accordance with the transmission mode.

Frequency selective transmit signal weighting for multiple antenna communication systems

Various aspects of a method and a system for finding a threshold for semi-orthogonal user group selection in multiuser MIMO downlink transmission are presented. Aspects of a system for semi-orthogonal user group selection may include a processor that computes an orthogonality measurement between one of a plurality of signals and at least one of a remaining portion of the plurality of signals. The processor may compare each of the orthogonality measurements to a threshold orthogonality value based on a computed probability. The processor may select a user group, based on the threshold orthogonality value, including one of the plurality of signals and one or more signals selected from the remaining portion of the plurality of signals.

Method and system for finding a threshold for semi-orthogonal user group selection in multiuser MIMO downlink transmission

Systems and methods that provide channel-adaptive antenna selection in multi-antenna element communication systems are provided. In one embodiment, a method that selects a subset of receive antennas of a receiver to receive a transmitted RF signal may include, for example, one or more of the following: establishing possible subsets of the receive antennas; determining sets of channel parameter statistics corresponding to the possible subsets of the receive antennas; computing output bit error rates of the receiver, each output bit error rate being computed based on at least one set of channel parameter statistics; selecting a particular possible subset of the receive antennas based upon a criterion predicated on the computed output bit error rates; and connecting one or more RF chains of the receiver to the receive antennas of the selected particular possible subset.

System and method for channel-adaptive antenna selection

A receiver operatively coupled to an antenna structure capable of receiving a first plurality of RF signals is disclosed herein. The receiver includes an RF processing network operative to perform weighting and combining operations within the RF domain using the first plurality of RF signals so as to produce a second plurality of RF signals. Also provided is a downconverter configured to downconvert the second plurality of RF signals into a second plurality of down-converted signals. In alternate implementations certain of the weighting and combining operations are performed at baseband and the remainder effected within the RF domain. A transmitter of corresponding architecture is also disclosed.

Multi-antenna communication systems utilizing RF-based and baseband signal weighting and combining

Certain aspects of the method may comprise receiving a plurality of spatially multiplexed communication signals from a plurality of transmit antennas at a base station. A plurality of vectors of baseband combined channel estimates may be generated based on phase rotation of the received plurality of spatially multiplexed communication signals. A plurality of pre-equalization weights may be generated based on the generated plurality of vectors of baseband combined channel estimates. The received plurality of spatially multiplexed communication signals may be modified based on the generated plurality of pre-equalization weights. At least a portion of the generated plurality of pre-equalization weights may be fed back to the base station for modifying subsequently transmitted spatially multiplexed communication signals which are transmitted from at least a portion of the plurality of transmit antennas at the base station.

Method and system for pre-equalization in a single weight spatial multiplexing MIMO system

Certain aspects of the method may comprise generating at least one control signal that may be utilized to control at least a first of a plurality of received spatially multiplexed communication signals. An amplitude and/or phase of the first received spatially multiplexed communication signal may be adjusted via the generated control signal so that the amplitude and/or phase of the first received spatially multiplexed communication signal may be equivalent to an amplitude and/or phase of a second received spatially multiplexed communication signal. The amplitude of the first received spatially multiplexed communication signal is adjusted within the processing path used to process the first received spatially multiplexed communication signal.

Method and system for implementing a single weight spatial multiplexing (SM) MIMO system

Systems and methods that provide channel-adaptive antenna selection in multi-antenna-element communication systems are provided. In one embodiment, a method that selects a subset of receive antennas of a receiver to receive a transmitted RF signal may include, for example, one or more of the following: establishing possible subsets of the receive antennas; determining sets of channel parameter statistics corresponding to the possible subsets of the receive antennas; computing output bit error rates of the receiver, each output bit error rate being computed based on at least one set of channel parameter statistics; selecting a particular possible subset of the receive antennas based upon a criterion predicated on the computed output bit error rates; and connecting one or more RF chains of the receiver to the receive antennas of the selected particular possible subset.

In a wireless system, a method and system for channel estimation in a single channel MIMO system comprising two-transmit and multiple-receive antennas for WCDMA/HSDPA are provided. A first receive antenna and at least one additional receive antenna may receive a plurality of SC communication signals transmitted from a first and an additional transmit antennas. Estimates of the propagation channels between transmit and receive antennas may be performed concurrently and may be determined from a baseband combined channel estimate. The integration time may be based on channel estimation accuracy and wireless modem performance. The signals received in the additional receive antennas may be multiplied by a rotation waveform to achieve channel orthogonality. The rotation waveform's amplitude and phase components may be modified based on the channel estimates. Rotation of the received signals in the additional receive antennas may be continuous or periodic.

Method and system for channel estimation in a single channel (SC) multiple-input multiple-output (MIMO) system comprising two-transmit (2-Tx) and multiple-receive (M-Rx) antennas for WCDMA/HSDPA

In wireless systems, a method and system for pre-equalization in a single weight (SW) single channel (SC) multiple-input multiple-output (MIMO) system are provided. A first receive antenna and at least one additional receive antenna may receive a plurality of SC communication signals transmitted from at least two transmit antennas. Estimates of the propagation channels between transmit and receive antennas may be performed concurrently and may be determined from baseband combined channel estimates. Channel weights may be determined to modify the signals received by the additional receive antennas. Pre-equalization weight parameters may be determined to modify subsequent signals transmitted from the transmit antennas. The pre-equalization weight parameters may be based on the propagation channel estimates and may be determined by LMS, RLS, DMI, or by minimizing a cost function. Closed loop transmit diversity may also be supported.

Method and system for pre-equalization in a single weight (SW) single channel (SC) multiple-input multiple-output (MIMO) system

Various aspects of a method and a system for a range reduction scheme for user selection in a multiuser MIMO downlink transmission are presented. Aspects of a system for range reduction may comprise a range reduction processor that determines a plurality of channel measurements corresponding to a plurality of signals. The range reduction processor may compute a plurality of channel capacities based on the channel measurements corresponding to a subset of the plurality of signals having channel gain that is greater than a remaining portion of the plurality of signals. Aspects of a method may comprise determining a plurality of channel measurements corresponding to a plurality of signals, and computing a plurality of channel capacities based on said channel measurements corresponding to a subset of the plurality of signals having a channel gain that is greater than a remaining portion of the plurality of signals.

Growing community of inventors

San Diego, CA, United States of America

Pieter Roux