Patent ID: 8014463
Filing Date: 2011-09-06
Classification: H04B

Abstract:
1. A transmitter usable for wireless communication, comprising: a plurality of transmit antennas, wherein each transmit antenna transmits a respective transmit signal; means for introducing respective time shifts to each of a plurality of spatial stream signals to produce a plurality of time-shifted spatial stream signals, wherein each of the plurality of spatial stream signals is based at least in part on a data stream; means for operating on each of the plurality of time-shifted spatial stream signals with a spatial rotation vector matrix to apply respective spatial rotation to each of the plurality of time-shifted spatial stream signals, to thereby map the plurality of time-shifted spatial stream signals respectively to the respective transmit signals that are respective time-shifted spatially-rotated spatial stream signals of a plurality of time-shifted spatially-rotated spatial stream signals, to reduce nulls, including deep nulls, associated with the data stream, in a received channel, wherein the spatial rotation vector matrix is a Walsh matrix; and means for transforming each of a plurality of spatial stream signals using an Inverse Fast Fourier Transform (IFFT), wherein the means for transforming is applied to the plurality of spatial stream signals before the means for introducing respective time shifts is applied to each of the plurality of spatial stream signals and before the means for operating on each of the plurality of time-shifted spatial stream signals with a spatial rotation vector matrix.