Intel Corporation

Iospan Wireless, Inc.

Iospan Wirless, Inc.

Gigabit Wireless, Inc.

Peroor K Sebastian

Arogyaswami J Paulraj

Robert Wendell Heath, Jr

David J Gesbert

Jose Tellado

Rahul Chopra

Rajeev Krishnamoorthy

Severine E Catreux

Shilpa Talwar

Partho Pratim Mishra

Victor Shtrom

Sanjay Kasturia

Manish Airy

Hemanth Sampath

John L Fan

Vinko Erceg

Baraa Al-Dabagh

Helmut B&ouml;lcskei

Helmut Boleskei

The present invention provides methods and apparatus for implementing spatial multiplexing in conjunction with the one or more multiple access protocols during the broadcast of information in a wireless network. One example includes transmitting a first and a second data signal to a remote unit from a respective first and a second spatially separate antenna of a base station so that the first and second data signals have a first spatial configuration, determining that the first and the second data signals are not spatially separated by the remote unit, reconfiguring the (spatial multiplexing logic) spatial configuration of the first and second data signals to a second spatial configuration, and transmitting a third and fourth data signal to the remote unit from a second different antenna configuration according to the second spatial configuration.

Spatial multiplexing in a cellular network

A wireless communications system is presented that adapts its mode of operation between spatial and non-spatial multiplexing in response to transmission-specific variables. Mode determination logic determines, in response to a received signal, if spatial or non-spatial multiplexing should be used to transmit a subscriber datastream between the BTS and the UE. The mode determination logic receives a measure of a transmission characteristic of the signal, compares the transmission characteristic to a transmission characteristic threshold and selects either spatial or non-spatial multiplexing in response to the comparison. The transmission characteristic includes at least one of delay spread, post-processing signal-to-noise ratio, CRC failure, residual inter-symbol interference, mean square error, coherence time, and path loss.

Wireless communications system that supports multiple modes of operation

Embodiments of a base transceiver station and method for transmitting are described herein. In some embodiments, data is transmitted over a downlink channel in accordance with a selected one of a plurality of transmission modes. The base transceiver station may be configurable to transmit data in accordance with each of the transmission modes. One of the transmissions modes may be selected for the data transmission based at least in part on feedback reported by a subscriber unit. The transmission modes include at least a single antenna mode, a transmit diversity mode, and a spatial multiplexing mode.

The present invention provides methods and apparatus for implementing spatial multiplexing in conjunction with the one or more multiple access protocols during the broadcast of information in a wireless network. A subscriber unit for use in a cellular system is disclosed. The subscriber unit includes: spatially separate receivers, a spatial processor, and a combiner. The spatially separate receivers receive the assigned channel composite signals resulting from the spatially separate transmission of the subscriber downlink datastream(s). The spatial processor is configurable in response to a control signal transmitted by the base station to separate the composite signals into estimated substreams based on information obtained during the transmission of known data patterns from at least one of the base stations. The spatial processor signals the base stations when a change of a spatial transmission configuration is required. The combiner combines the estimated substreams into a corresponding subscriber datastream.

A method of maximizing a communication parameter, such as data capacity, signal quality or throughput of a channel between a transmit unit with M transmit antennas and a receive unit with N receive antennas and a communication system such as a wireless network (including networks with multiple access techniques such as TDMA, FDMA, CDMA, OFDMA) employing the method. The data is first processed to produce parallel spatial-multiplexed streams SM, where i=1 . . . k, which are converted or mapped to transmit signals TS, where p=1 . . . M, assigned for transmission from the M transmit antennas. Corresponding receive signals RS, where j=1 . . . N, are received by the N receive antennas of the receiver and used to assess a quality parameter, such as a statistical signal parameter including SINR, SNR, power level, level crossing rate, level crossing duration of the signal of a predetermined threshold and reception threshold, or a parameter of the data, such as BER or packet error rate. The quality parameter is used to adaptively adjust k as well as other parameters such as coding and mapping to transmit antennas such that the communication parameter of the channel is maximized.

Method and wireless systems using multiple antennas and adaptive control for maximizing a communication parameter

A wireless communications adapts its mode of operation between spatial multiplexing and non-spatial multiplexing in response to transmission-specific variables. An embodiment of a wireless communications system for transmitting information between a base transceiver station and a subscriber unit includes mode determination logic. The mode determination logic is in communication with the base transceiver station and the subscriber unit. The mode determination logic determines, in response to a received signal, if a subscriber datastream should be transmitted between the base transceiver station and the subscriber unit utilizing spatial multiplexing or non-spatial multiplexing. In an embodiment, the mode determination logic has an input for receiving a measure of a transmission characteristic related to the received signal. In an embodiment, the mode determination logic includes logic for comparing the measured transmission characteristic to a transmission characteristic threshold and for selecting one of spatial multiplexing and non-spatial multiplexing in response to the comparison of the measured transmission characteristic to the transmission characteristic threshold. In an embodiment, the transmission characteristic includes at least one of delay spread, post-processing signal-to-noise ratio, cyclical redundancy check (CRC) failure, residual inter-symbol interference, mean square error, coherence time, and path loss. By adapting the mode of operation in response to transmission-specific variables, the use of spatial multiplexing can be discontinued in unfavorable conditions. Additionally, because the wireless communications system can adapt its mode of operation between spatial multiplexing and non-spatial multiplexing, the communications system is compatible with both subscriber units that support spatial multiplexing and subscriber units that do not support spatial multiplexing.

A method and communication system for selecting a mode for encoding data for transmission in a wireless communication channel between a transmit unit and a receive unit. The data is initially transmitted in an initial mode and the selection of the subsequent mode is based on a selection of first-order and second-order statistical parameters of short-term and long-term quality parameters. Suitable short-term quality parameters include signal-to-interference and noise ratio (SINR), signal-to-noise ratio (SNR), power level and suitable long-term quality parameters include error rates such as bit error rate (BER) and packet error rate (PER). The method of the invention can be employed in Multiple Input Multiple Output (MIMO), Multiple Input Single Output (MISO), Single Input Single Output (SISO) and Single Input Multiple Output (SIMO) communication systems to make subsequent mode selection faster and more efficient. Furthermore the method can be used in communication systems employing various transmission protocols including OFDMA, FDMA, CDMA, TDMA.

Mode selection for data transmission in wireless communication channels based on statistical parameters

A wireless communications adapts its mode of operation between spatial multiplexing and non-spatial multiplexing in response to transmission-specific variables. An embodiment of a wireless communications system for transmitting information between a base transceiver station and a subscriber unit includes mode determination logic. The mode determination logic is in communication with the base transceiver station and the subscriber unit. The mode determination logic determines, in response to a received signal, if a subscriber data stream should be transmitted between the base transceiver station and the subscriber unit utilizing spatial multiplexing or non-spatial multiplexing.

A method and communication system for selecting a mode for encoding data for transmission in a wireless communication channel between a transmit unit and a receive unit. The data is initially transmitted in an initial mode and the selection of the subsequent mode is based on a selection of first-order and second-order statistical parameters of short-term and long-term quality parameters. Suitable short-term quality parameters include signal-to-interference and noise ratio (SINR), signal-to-noise ratio (SNR), power level and suitable long-term quality parameters include error rates such as bit error rate (BER) and packet error rate (PER). The method of the invention can be employed in Multiple Input. Multiple Output (MIMO), Multiple Input Single Output (MISO), Single Input Single Output (SISO) and Single Input Multiple Output (SIMO) communication systems to make subsequent mode selection faster and more efficient. Furthermore the method can be used in communication systems employing various transmission protocols including OFDMA, FDMA, CDMA, TDMA.

The present invention provides methods and apparatus for implementing spatial multiplexing in conjunction with the one or more multiple access protocols during the broadcast of information in a wireless network. A subscriber unit for use in a cellular system is disclosed. The subscriber unit includes a plurality of spatially separate antennas and a transmitter for transmitting a plurality of substreams of a datastream on an assigned channel or slot of a multiple access protocol. The transmitter is arranged to apply each substream to an associated one of the spatially separate antennas.

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Mountain View, CA, United States of America

Peroor K Sebastian