Patent ID: 8428158
Filing Date: 2013-04-23
Classification: H04L

Abstract:
1. A method of generating channel estimates performed by an Orthogonal Frequency Division Multiple Access (OFDMA) receiver of a mobile station, the method comprising: initially identifying a serving base station and one or more interfering base stations from base station identifiers contained within preamble symbols, the preamble symbols comprising OFDMA transmissions transmitted by the base stations; allocating two or more orders of a recursive filter to a main channel associated with the serving base station and allocating additional orders of the recursive filter to one or more interfering channels associated with the interfering base stations; and performing symbol-by-symbol recursive filtering with the recursive filter on one or more pilot subcarriers of received symbols of an OFDMA frame using a pilot subcarrier modulation sequence associated with the serving base station and pilot subcarrier modulation sequences associated with the one or more interfering base stations to generate channel estimates on a symbol-by-symbol basis for the main channel and the one or more interfering channels; wherein the recursive filter is a Kalman filter initialized to have four orders, wherein when one interfering base station is identified as an interferer, the method comprises: allocating three of the four orders of the recursive filter to track the main channel; and allocating one of the four orders of the recursive filter to track an interfering channel associated with the one interfering base station, and wherein when two interfering base stations are identified as interferers, the method comprises: allocating two of the four orders of the recursive filter to track the main channel; and allocating two of the four orders of the recursive filterer to track interfering channels associated with the two identified interfering base stations.