Patent ID: 8199845
Filing Date: 2012-06-12
Classification: H04L

Abstract:
1. In a wireless base-station having one or more radio frequency (RF) receivers, a method comprising: receiving a group of signals from one or more wireless communication devices using uplink (UL) spatial division multiple access (SDMA) communications via an antenna array; performing fast Fourier transform (FFT) operations on the received group of signals; and arranging a resultant group of transformed signals into tiles, according to a partial usage of sub-channels (PUSC) tile structure for UL SDMA; calculating a timing error estimate corresponding to the wireless communication device; generating a practical channel estimate by using an average of timing error estimates to modify an estimate of a channel that substantially represents a perfectly synchronized channel; separating, via an equalizer enhanced with the practical channel estimate, superposed symbols from multiple wireless communication devices into individual wireless communication device symbols; providing a timing error correction for the one or more wireless communication devices via the equalizer; and enabling an inexplicit frequency error correction for individual wireless communication device signals after the superposed symbols are separated and after the timing error correction.