Abstract: A method performed by a wireless device functioning as a beamformee station in a wireless network to perform a sounding procedure. The method includes wirelessly receiving a null data packet (NDP) announcement frame from a beamformer station, wherein the NDP announcement frame includes an indication of whether the beamformee station should acknowledge the NDP announcement frame and responsive to determining that the NDP announcement frame includes an indication that the beamformee station should acknowledge the NDP announcement frame, wirelessly transmitting an acknowledgement frame for the NDP announcement frame to the beamformer station.

Abstract: Data signals are received over a shared spectrum in a code division multiple access communication format as a combined signal. The combined signal is sampled as a plurality of received vector versions. A plurality of system matrices and an associated covariance matrix using codes and estimated impulse responses of the data signals is produced. Each system matrix corresponds to a received vector version. The system and covariance matrices are extended and approximated as block circulant matrices. A diagonal matrix of each of the extended and approximated system and covariance matrices are determined by prime factor algorithm-fast Fourier transform (PFA-FFT)without division of the matrix. The received vector versions are extended. A product of the diagonal matrices and the extended received vector versions is taken. An inverse block discrete Fourier transform is performed by a PFA-FFT a on a result of the product to produce the estimated data.

Abstract: Digital precoding filter for a transmission filter (6) for minimizing the chrest [sic] factor of the signal (y) output by the transmission filter (6), having a modulo adder (22) of the source data symbols which are received from a data symbol source (2) at a signal input (15) of the precoding filter (4), and added with fedback filtered transmission data symbols to transmission output data symbols (p) which are output to the downstream transmission filter (6) via a signal output (41) of the precoding filter (4); and a digital feedback filter (36) which filters the transmission output data symbols present at the signal output (41) and feeds them back to the modulo adder (22), and that [sic] a digital correction filter (39) is connected to the signal output (41), the filter coefficients of the digital correction filter (39) being set as a function of the normalized pulse response of the transmission filter (6) in the case of that sampling phase (?) for which the output signal of the transmission filter (6) has a