Wisconsin Alumni Research Foundation

John H Brady

Akbar Muhammad Sayeed

A receiver detects a plurality of information symbols. A first signal and a second signal are received from a first transmitted signal and a second transmitted signal, respectively, transmitted by a first plurality of antennas and received by a second plurality of antennas connected to the receiver. The second signal is received after the first signal. The receiver spatially filters the first signal using a spatial filter matrix. The receiver computes a conjugate of the first filtered signal to define a conjugate first signal, and spatially filters a second signal using the spatial filter matrix. The receiver computes a Hadamard product of the first filtered signal and the conjugate first signal to define a differential measurement signal. The receiver detects the plurality of information symbols from the differential measurement signal.

Differential MIMO transceiver

A method of estimating a spatial filter matrix is provided. A conjugate of a received first signal defines a conjugate first signal. A Kronecker product of the defined first signal and a received second signal define a differential measurement signal. The computations are repeated for a plurality of first and second signals sufficient to compute an estimate of a channel matrix from the differential measurement signals. A spatial filter matrix is computed from the computed estimate of the channel matrix. The computed spatial filter matrix is used in a data communication phase between the first plurality of antennas and the second plurality of antennas.

Beam measurement values are computed by transforming a signal to a beamspace representation using a beamforming matrix that includes a plurality of columns that define a plurality of beams. A second plurality of beams is selected from the plurality of beams based on a power captured by each beam derived from the computed beam measurement values. For each beam of the second plurality of beams as a first beam, a spatial phase shift component and a temporal delay component is computed based on the fixed spatial angle associated with the first beam and a carrier frequency, a filter is defined using the spatial phase shift component and the temporal delay component, a beam measurement value associated with the first beam from the computed beam measurement values is selected, and the defined filter is applied to the selected beam measurement value to define a filtered value.

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Madison, WI, United States of America

John H Brady